1) Researchers screened 65 soybean genotypes for their ability to form symbiotic relationships with Bradyrhizobium strains to fix nitrogen.
2) Plants were inoculated with either a cowpea-type or soybean-type Bradyrhizobium strain, or a non-inoculated control. Significant differences were found between genotypes in nodule formation.
3) Twelve genotypes formed over 10 nodules per plant and had over 50 mg dry weight of nodules, showing high responsiveness to the cowpea-type Bradyrhizobium strain. These 12 genotypes are proposed as potential parents for breeding promiscuous soybean varieties.
Elucidation of cow tick Rhipicephalus microplus (formerly Boophilus microplus...Innspub Net
Ticks comprise one of the most significant groups of arthropods in terms of effects on animal health. They incapacitate the host by feeding on it. The cattle tick, economically impact cattle industry in tropical and subtropical regions of the world, is a cautiously serious external parasite affecting, primarily, cattle. These ticks are adapted to the advantages of specialising to feed on cattle and with all the feeding stages occurring on one individual host in a rapid sequence of reproduction. Cattle tick’s reproduction and life cycle occurs on body of only one host. This stage takes approximately 21 days, during which the tick changes from a minute larva to a nymph and finally an adult. With the use of a thin-tipped tweezers or forceps with a steady even pressure, ticks were removed straight upward from different body parts of cattle. Ticks were identified to the species level based on their morphologic features under a dissecting microscope and their genus and species were identified under the stereo microscope in the laboratory. Several parameters were taken as to with its life cycle. As observed, the period of tick’s life cycle varies due to some factors. This study aims to elucidate the reproduction process and life cycle of cattle ticks to serve as a guide in controlling and managing these parasitic creatures. Get more articles at: http://www.innspub.net/volume-6-number-4-april-2015-jbes/
Glyphosate resistance trait into soybean Cuban varieties: agronomical assessm...Innspub Net
Glyphosate-resistant (GR) soybean was one of the first major applications of genetic engineering in field crops and offered farmers a vital tool in fighting weeds. Weeds are a problem for soybean production in Cuba, so our work aim was the GTS 40-3-2 event introgression into Cuban varieties. Two local cultivars were crossed with transgenic genotypes that carry the event. From F1 to F3 generations, individual plants that produced more than 60 g of seeds per plant were chosen to obtain next generation. Individual lines were selected from F4 generation. F5 and F6 generations of five selected transgenic lines and their relatives were chosen to evaluate seven
agronomic traits throughout the summers of 2012 and 2013. A Random Block experimental design was done. First flowering (R1) and maturity (R8) stages of all genotypes were affected by planting date. Plant height of I1B2- 3, I1B4, I36B4 and RP5 lines ranged from 80 to 111 cm. I1B2-2 and I1B2-3 lines would be suitable for mechanized harvesting because they had the insertion of the first pod at 14.63 cm and 13.93 cm respectively. I36B4 line produced the greatest number of pods per plant (127). Transgenic lines produced more than 180 seeds per plant and 100-seed weight ranged from 13.75 g to 17.46 g. Seed yield per plant of transgenic lines and their parents IncaSoy36, CEB2 and CEB4 weren’t statistically different. These results could be a start point for other studies
involving larger areas, different planting dates and localities. Get more articles at: http://www.innspub.net/volume-7-number-4-october-2015-ijaar/
Evaluation of rice genotypes for resistance to the stalk-eyed fly (Diopsis lo...Innspub Net
Globally, rice production is limited by abiotic and biotic factors. Of the insect pests attacking rice, the stalk-eyed fly is the most abundant. Major rice growing districts in Uganda are affected, and varieties grown by farmers are susceptible. The objective of this study was to identify sources of resistance to stalk-eyed flies among improved rice genotypes in Uganda. Fifty genotypes from the Africa Rice Centre, IRRI, South Korea and the National Crops Resources Research Institute (NaCRRI) in Uganda were screened under cage and field conditions at NaCRRI. Trials were laid out in an alpha lattice design, with 3 replications, for both experiments. Natural infestation (D. longicornis or D. apicalis) was used in the field while cage trials utilized artificial infestation with D. longicornis. Data on deadhearts were collected from seedling to tillering stages, at 7, 14, 21 and 28 days. Analyses of variance were performed using restricted maximum likelihood. Infestation levels for 31 (62%) rice genotypes were the same under both field and cage conditions, 4 (8%) genotypes showed higher susceptibility in the cage than in the field and 15 (30%) were more resistant in the cage than in the field. Genotypes NERICA 4, TXD306, NM7-22-11-B-P-1-1 and K85 were identified as the most resistant varieties. F3 genotypes (GSR IR1- 5-S14-S2-Y1 x K85, Gigante x NERICA4, NERICA4 x Gigante, NERICA1x NERICA4, NERICA4 x NERICA6, and NERICA4 x SUPA) were also found resistant. These genotypes were recommended for release and further advancement, respectively.
seeds potentialities of medicks in sub humid area to be used in steppe zoneIJEAB
New pulse crops varieties more productive as medics should be made available to breeders located in semi-arid region of Algeria. So, and through two years of testing, pods yield and seeds production of twenty populations belonging to species M.intertexta , M.ciliaris, M.polymorpha , M.Truncatula and an introduced population M.muricoleptis is an Australian cultivar (Jemalong) are appreciated.Pods’ yields of year 2013 vary between 78,66g/m² with poly27 and 3637,33g/m² with I107. Values of the second essay (2015) are different, they vary between 40,89g /m² with Poly236 and 464,36 g/m² with I11.The cultivar Jemalong offers a yield of 172,4 g/m². The corresponding seed yields also show a low production in year 2015. The ratio leaf / stem varies between 1,03 and 5. The average of yields in dry matter of 27 populations in 2013 was of 457,79g/m2 against 127,41 g/m² in 18 populations in 2015. Jemalong cultivar records a yield of 12,8g/m². For the same dose of seed, number of plants by square meter varies between 44 and 112. Number of stems by square meter varies between 136 in C204 and 420 in I52..The average width of population’s ramifications varies between 13cm in Tr334 and 44 cm in I52, The Jemalong cultivar offers an average of 17cm. So, production results of medicks depend of weather conditions in littoral zone of lower altitude than 600-700m. In steppe zones, we recommend to make tests in situ with these same populations.
Estimation of genetic parameters and gene actions of sorghum [Sorghum bicolor...Innspub Net
A study of sorghum tolerance to low P condition was conducted in two experiments : (1) in nutrient solution and
(2) in acid soil. The aim of this study was to obtain information on the genetic variability and heritability of agronomic characters that could be used as selection criteria in low P condition and to obtain information on gene action that controlled agronomic characters of sorghum.The plant materials used in this experiment were F2 segregating population derived from the cross between B69 and Numbu. The first experiment was conducted in the green house of Bogor Agricultural University. B69, Numbu and F2 population were grown hidroponically for 14 days. Composition of the nutrient solution used in the experiment followed the method suggested by Ohki with modification of P concentration. P is given in the form of KH2PO4: 0.001 mM. The results showed that shoot dry weight (SDW) and total dry weight (TDW) had high estimate of heritability and moderate genotypic
coefficient of variance (GCV), thus these characters can be used for criteria selection for low P tolerance at seedling stage. The significant value of skweness from the distribution shoot dry weight in F2 segregants, indicate the presence of complementary epistasis gene action, whereas normal distribution of total dry weight showed additive gene action. The second experiment was conducted in acid soils of Bogor District Experimental Field Tenjo, Bogor. The results showed that stem diameter, panicle weight and grain yield per plant had high heritability and wide GCV value, indicating these characters can be used as the selection criteria in selecting
sorghum genotypes for low P tolerance in acid soil. Based on the skewness values, all of the agronomy characters
observed in this study were influenced by additive gene action. Get more articles at: http://www.innspub.net/volume-7-number-3-september-2015-ijaar/
The pattern of field infestation by the flea beetles, Podagrica spp., was assessed in okra-kenaf intercrop system with a view to determining a cropping pattern that would assist in controlling the pest problem. Okra and kenaf were intercropped in row combinations of 1:1, 1:2, 2:1 and 2:2 while sole-cropped okra and kenaf served for comparison. Field sampling for flea beetles commenced three weeks after planting and it lasted till the 12th week, a period that extended to the postharvest stage of okra. There was a significant difference (P Ë‚ 0.01) between the population of the two Podagrica spp. (with P. uniforma being more abundant than P. sjostedti) and among the six planting patterns. The pest population also differed (P Ë‚ 0.05) between the two crops and among (P Ë‚ 0.001) the vegetative, reproductive and postharvest stages of okra. Sole kenaf had a significantly higher level of infestation by the flea beetles followed by sole okra and two rows of okra intercropped with one row of kenaf in descending order. All the other three intercrop patterns had a significantly lower infestation level. Kenaf attracted more flea beetles than okra at the vegetative stage while stumps of okra left in the field after harvesting was over sustained a significantly higher population of flea beetles. Obtained results showed that intercropping could be used, especially by poor rural farmers, as a pest control strategy against Podagrica spp. Due to the considerable population of flea beetles sustained by okra stumps, farmers should be encouraged to get rid of leftovers after harvesting as a way of further controlling Podagrica spp. The combination of intercropping and farm sanitation would assist in reducing reliance on synthetic chemical insecticides.
Elucidation of cow tick Rhipicephalus microplus (formerly Boophilus microplus...Innspub Net
Ticks comprise one of the most significant groups of arthropods in terms of effects on animal health. They incapacitate the host by feeding on it. The cattle tick, economically impact cattle industry in tropical and subtropical regions of the world, is a cautiously serious external parasite affecting, primarily, cattle. These ticks are adapted to the advantages of specialising to feed on cattle and with all the feeding stages occurring on one individual host in a rapid sequence of reproduction. Cattle tick’s reproduction and life cycle occurs on body of only one host. This stage takes approximately 21 days, during which the tick changes from a minute larva to a nymph and finally an adult. With the use of a thin-tipped tweezers or forceps with a steady even pressure, ticks were removed straight upward from different body parts of cattle. Ticks were identified to the species level based on their morphologic features under a dissecting microscope and their genus and species were identified under the stereo microscope in the laboratory. Several parameters were taken as to with its life cycle. As observed, the period of tick’s life cycle varies due to some factors. This study aims to elucidate the reproduction process and life cycle of cattle ticks to serve as a guide in controlling and managing these parasitic creatures. Get more articles at: http://www.innspub.net/volume-6-number-4-april-2015-jbes/
Glyphosate resistance trait into soybean Cuban varieties: agronomical assessm...Innspub Net
Glyphosate-resistant (GR) soybean was one of the first major applications of genetic engineering in field crops and offered farmers a vital tool in fighting weeds. Weeds are a problem for soybean production in Cuba, so our work aim was the GTS 40-3-2 event introgression into Cuban varieties. Two local cultivars were crossed with transgenic genotypes that carry the event. From F1 to F3 generations, individual plants that produced more than 60 g of seeds per plant were chosen to obtain next generation. Individual lines were selected from F4 generation. F5 and F6 generations of five selected transgenic lines and their relatives were chosen to evaluate seven
agronomic traits throughout the summers of 2012 and 2013. A Random Block experimental design was done. First flowering (R1) and maturity (R8) stages of all genotypes were affected by planting date. Plant height of I1B2- 3, I1B4, I36B4 and RP5 lines ranged from 80 to 111 cm. I1B2-2 and I1B2-3 lines would be suitable for mechanized harvesting because they had the insertion of the first pod at 14.63 cm and 13.93 cm respectively. I36B4 line produced the greatest number of pods per plant (127). Transgenic lines produced more than 180 seeds per plant and 100-seed weight ranged from 13.75 g to 17.46 g. Seed yield per plant of transgenic lines and their parents IncaSoy36, CEB2 and CEB4 weren’t statistically different. These results could be a start point for other studies
involving larger areas, different planting dates and localities. Get more articles at: http://www.innspub.net/volume-7-number-4-october-2015-ijaar/
Evaluation of rice genotypes for resistance to the stalk-eyed fly (Diopsis lo...Innspub Net
Globally, rice production is limited by abiotic and biotic factors. Of the insect pests attacking rice, the stalk-eyed fly is the most abundant. Major rice growing districts in Uganda are affected, and varieties grown by farmers are susceptible. The objective of this study was to identify sources of resistance to stalk-eyed flies among improved rice genotypes in Uganda. Fifty genotypes from the Africa Rice Centre, IRRI, South Korea and the National Crops Resources Research Institute (NaCRRI) in Uganda were screened under cage and field conditions at NaCRRI. Trials were laid out in an alpha lattice design, with 3 replications, for both experiments. Natural infestation (D. longicornis or D. apicalis) was used in the field while cage trials utilized artificial infestation with D. longicornis. Data on deadhearts were collected from seedling to tillering stages, at 7, 14, 21 and 28 days. Analyses of variance were performed using restricted maximum likelihood. Infestation levels for 31 (62%) rice genotypes were the same under both field and cage conditions, 4 (8%) genotypes showed higher susceptibility in the cage than in the field and 15 (30%) were more resistant in the cage than in the field. Genotypes NERICA 4, TXD306, NM7-22-11-B-P-1-1 and K85 were identified as the most resistant varieties. F3 genotypes (GSR IR1- 5-S14-S2-Y1 x K85, Gigante x NERICA4, NERICA4 x Gigante, NERICA1x NERICA4, NERICA4 x NERICA6, and NERICA4 x SUPA) were also found resistant. These genotypes were recommended for release and further advancement, respectively.
seeds potentialities of medicks in sub humid area to be used in steppe zoneIJEAB
New pulse crops varieties more productive as medics should be made available to breeders located in semi-arid region of Algeria. So, and through two years of testing, pods yield and seeds production of twenty populations belonging to species M.intertexta , M.ciliaris, M.polymorpha , M.Truncatula and an introduced population M.muricoleptis is an Australian cultivar (Jemalong) are appreciated.Pods’ yields of year 2013 vary between 78,66g/m² with poly27 and 3637,33g/m² with I107. Values of the second essay (2015) are different, they vary between 40,89g /m² with Poly236 and 464,36 g/m² with I11.The cultivar Jemalong offers a yield of 172,4 g/m². The corresponding seed yields also show a low production in year 2015. The ratio leaf / stem varies between 1,03 and 5. The average of yields in dry matter of 27 populations in 2013 was of 457,79g/m2 against 127,41 g/m² in 18 populations in 2015. Jemalong cultivar records a yield of 12,8g/m². For the same dose of seed, number of plants by square meter varies between 44 and 112. Number of stems by square meter varies between 136 in C204 and 420 in I52..The average width of population’s ramifications varies between 13cm in Tr334 and 44 cm in I52, The Jemalong cultivar offers an average of 17cm. So, production results of medicks depend of weather conditions in littoral zone of lower altitude than 600-700m. In steppe zones, we recommend to make tests in situ with these same populations.
Estimation of genetic parameters and gene actions of sorghum [Sorghum bicolor...Innspub Net
A study of sorghum tolerance to low P condition was conducted in two experiments : (1) in nutrient solution and
(2) in acid soil. The aim of this study was to obtain information on the genetic variability and heritability of agronomic characters that could be used as selection criteria in low P condition and to obtain information on gene action that controlled agronomic characters of sorghum.The plant materials used in this experiment were F2 segregating population derived from the cross between B69 and Numbu. The first experiment was conducted in the green house of Bogor Agricultural University. B69, Numbu and F2 population were grown hidroponically for 14 days. Composition of the nutrient solution used in the experiment followed the method suggested by Ohki with modification of P concentration. P is given in the form of KH2PO4: 0.001 mM. The results showed that shoot dry weight (SDW) and total dry weight (TDW) had high estimate of heritability and moderate genotypic
coefficient of variance (GCV), thus these characters can be used for criteria selection for low P tolerance at seedling stage. The significant value of skweness from the distribution shoot dry weight in F2 segregants, indicate the presence of complementary epistasis gene action, whereas normal distribution of total dry weight showed additive gene action. The second experiment was conducted in acid soils of Bogor District Experimental Field Tenjo, Bogor. The results showed that stem diameter, panicle weight and grain yield per plant had high heritability and wide GCV value, indicating these characters can be used as the selection criteria in selecting
sorghum genotypes for low P tolerance in acid soil. Based on the skewness values, all of the agronomy characters
observed in this study were influenced by additive gene action. Get more articles at: http://www.innspub.net/volume-7-number-3-september-2015-ijaar/
The pattern of field infestation by the flea beetles, Podagrica spp., was assessed in okra-kenaf intercrop system with a view to determining a cropping pattern that would assist in controlling the pest problem. Okra and kenaf were intercropped in row combinations of 1:1, 1:2, 2:1 and 2:2 while sole-cropped okra and kenaf served for comparison. Field sampling for flea beetles commenced three weeks after planting and it lasted till the 12th week, a period that extended to the postharvest stage of okra. There was a significant difference (P Ë‚ 0.01) between the population of the two Podagrica spp. (with P. uniforma being more abundant than P. sjostedti) and among the six planting patterns. The pest population also differed (P Ë‚ 0.05) between the two crops and among (P Ë‚ 0.001) the vegetative, reproductive and postharvest stages of okra. Sole kenaf had a significantly higher level of infestation by the flea beetles followed by sole okra and two rows of okra intercropped with one row of kenaf in descending order. All the other three intercrop patterns had a significantly lower infestation level. Kenaf attracted more flea beetles than okra at the vegetative stage while stumps of okra left in the field after harvesting was over sustained a significantly higher population of flea beetles. Obtained results showed that intercropping could be used, especially by poor rural farmers, as a pest control strategy against Podagrica spp. Due to the considerable population of flea beetles sustained by okra stumps, farmers should be encouraged to get rid of leftovers after harvesting as a way of further controlling Podagrica spp. The combination of intercropping and farm sanitation would assist in reducing reliance on synthetic chemical insecticides.
Field experiments were conducted to investigate the variations in sixteen maize genotypes in relation to drought tolerance. The experimental set up was subjected to drought stress after five weeks of planting for three weeks before data on morphological and yield characters of maize genotypes were obtained for three cropping years. Plant height and grain yield of Bodija yellow maize were the highest overall. There was a significant difference among genotypes for drought stress resistance and Bodija yellow maize showed the most tolerance, while TZBR Comp 1 – C1 S2 510 genotype was the least. First principal component axis (Prin 1) had the highest contribution to the variation of the morphological, yield and drought tolerance traits. Prin 1 was highly related to the morphological and yield characters more than to the drought resistance. Plant height was negatively and strongly correlated (p<0.01) with stem height, number of leaves, stem girth, leaf length, leaf width and week after planting, but negatively correlated with the drought resistance. Therefore, Bodija yellow maize should be considered as parent material in breeding for the development of drought tolerant traits in maize.
Genetic control and heterosis depend directly on genetic divergence among the parents in generating promising hybrids
required by plant breeders. The purpose of this study was to determine the relative importance of heterosis, combining
abilities, regression and correlation estimates in order to develop hybrid cultivars in maize. The 28 F1 hybrids obtained by
partial diallel cross of 8 inbreds in a randomized complete block design were evaluated at the Lower Niger River Basin
Authority, Oke-Oyi, Nigeria in three years. General (GCA) and specific combining abilities (SCA) produced significant (P
< 0.01) effects for all the characters, while non-additive genetic effects were predominant. The levels of heterosis for grain
yield varied widely among crosses, ranging from -16.83 to 9.76%. Positive and significant genotypic and phenotypic
correlations among grain yield and some related characters (days to anthesis and silking; plant and ear heights; number of
ears plant-1 and 1000 seed weight) showed that each character could be used indirectly to selection of grain yield. These
results also indicated that SCA was more effective than heterosis for describing hybrid performance. The regression of
actual hybrid characters on the expected hybrid characters, based on parental GCA values, was highly significant.
Regression analysis also showed that all the agronomic characters jointly contributed 19.4% to grain yield of maize. The
inbreds (Pop 66 SR and 2000 EV DT-Y STRC4) and crosses (Pop 66 SR x, 2000 EV DT-Y STRC4, Pop 66 SR x KU1409
and 9006 x KU1409) featured prominently with respect to better GCA × Year and SCA × Year effects with high heterotic
values for maize grain yield and associated characters. These inbreds could serve as donors to obtain early and short
statured hybrids with higher yield, while the crosses may be exploited and adapted to the Nigerian Savannas. This study
also affirmed that genotypic and phenotypic correlation coefficients as well as combining abilities, heterosis and regression
analyses were found to be suitable models for yield improvement in maize breeding.
Development of drought tolerant maize cultivars is prerequisite to achieving stable grain yield in
drought–prone ecologies of Nigeria’s Guinea savanna. However, success has been limited mainly due
to lack of maize genotypes that show clear differences in response to well defined moisture deficit
condition. Two sets of drought tolerant (DT) maize germplasm were evaluated under screenhouse and
field conditions between 1999 and 2002. In the screenhouse study, performances of the genotypes
were compared under well-watered condition and moisture deficit imposed at different growth stages.
Under field conditions, the first set comprising 11 accessions along with a check were evaluated for 4
growing seasons while the second set which comprised 3 DT varieties were evaluated along with 2
check varieties using monthly plantings between April and August of 2001 and 2002, respectively. In
the first set, post anthesis moisture deficit significantly reduced grain yield by 25 to 73.5% in the open
pollinated varieties (OPVs) and by 20 to 64% in the hybrids. Grain yield under field conditions ranged
from 2.48 to 3.49, 2.82 to 3.73 and 3.58 to 4.76 tons/ha-1 for 1999, 2000 and 2001 full growing seasons,
respectively, and 2.03 to 2.50 tons/ha-1 for 2000 late growing season. In the second set, pre and post
anthesis moisture deficits reduced grain yield by 77.6 and 95.8%, respectively, of well watered
condition while in the field, grain yields in the genotypes were highest for plantings made in April and
July (1.90 - 2.5 t/ha), lowest for August (0.7 -1.8 t/ha) when moisture deficit coincided with
reproductive phase. Yield stability exhibited under moisture deficit and on the field by 8522-2, Oba
super 2 and AK9943-DMRSR in the first set as well as DT-SR-Y C0 and DT-SR-W C0 in the second set,
indicates their suitability either as cultivars per se or as potential source of DT alleles for
development of DT maize varieties for Nigeria’s savanna ecologies.
Pulses R & D in India by Dr. S K Datta, Deputy Director General, Indian Council of Agricultural Research. Presentation at The Pulses Conclave 2014 by India Pulse & Grains Association, IPGA
Effect of Different Weed Control Practices On Proximate Composition, Nutrient...IOSRJAVS
A field experiment was conducted during 2004 and 2005 cropping seasons to determine effect of different weed control practices on proximate composition, nutrient concentration and nutrient uptake of maize (Zea maysL.) at the Teaching and Research Farm of Ambrose Alli University, Ekpoma, Nigeria. Seven treatments were used for the experiment, viz no weeding (control), Primextra (3.0kg a.i./ha), mulching (wood shavings), one- hoe weeding at 3 weeks after planting (WAP), two hoe- weedings at 3 and 7 WAP, cover cropping with melon minus hoe-weeding, cover-cropping with melon plus one hoe-weeding at 3WAP. The seven treatments were laid out in randomized complete block design with four replicates. Results showed that mulched plot with wood shavings had the lowest weed density and highest proximate composition, grain nutrient concentration, ear leaf concentration and nutrient uptake followed by Primextra treated plot .The study recommends that small holder farmers to adopt mulching technique with wood shaving to improve the nutritional quality of maize grain since it does not involve any technical rigor besides signifying a non-chemical weed control.
Incidence and toxigenicity of fungi contaminating sorghum from NigeriaPremier Publishers
Each Agro ecological zone was transversely delineated into 5 districts and five villages (at least 20 Km from each other) called “locations” were selected in each district. In each district, Sorghum grains in stores, bunches in the field and sorghum grains in the market were sampled from five locations, each approximately 20 km from the previous sampling location. The mycological analytical procedures were performed under aseptic condition. Plates were counted for fungal colonies using a colony counter and the number of fungal colonies per gram of sample was calculated as CFU/g. The fungi species were isolated and subsequently identified using MEA/CYA media for Aspergillus and Penicillium species and PDA for the fusarium species Toxigenicity studies on strains representing species of Aspergillus, Penicillium, Fusarium was carried out to determine their ability to produce aflatoxin B1 (AFB1); aflatoxin B2 (AFB2); aflatoxin G1 (AFG1); aflatoxin G2 (AFG2); OTA, ZEN, DON and FB1. A total of 701 isolates were recorded which consist of 67 confirmed fungal strains. Aspergillus species formed the majority with 346(49.6%) followed by the Fusarium species with 186(26.7%) then Penicillium species with 102(14.6%) while others such as Cuvularia, Phoma, Alternaria, Rhizormucor constitutes 67 (9.0% )strains of the total population.
Study on Distribution of Microbial and Diazotrophic Azotobacter Population in...Agriculture Journal IJOEAR
Abstract— The current scenario encounters the steady demand of food supply and the application of fertilizer is become an indispensable in modern agriculture. Hence, the present study is focused on distribution of microbial and diazotrophic Azotobacter population in rhizosphere soil sample. Total microbial population viz, bacteria, fungi, actiomycetes and diazotrophic Azotobacter were enumerated from five different rhizosphere soil samples and compared the distribution of diazotrophic Azotobacter with other three microbial groups. The results of enumeration of total microbial population reveals that comparatively the bacterial population found to be higher followed by Azotobacter population in various rhizosphere soil. Based on the predominant growth, five Azotobacter strains (one isolate from each sample) were isolated and authenticated through morphological and biochemical characteristics.
Impacts of Plant Growth Promoting Rhizobacteria Inoculation Configurations on...AI Publications
The main objective of this study is determine the responses of Bambara groundnut [Vigna subterranea (L). Verdc.] to application methods of plant growth promoting rhizobacteria inoculant and time of sowing after inoculation in Agbani area of Enugu, South East Nigeria. Field trials were conducted at the Teaching and Research Farm of the Faculty of Agriculture and Natural Resources management, Enugu State University of Science and Technology in 2015 and 2016 planting season. The experiment was a 2 × 3 factorial trial in a randomized complete block design with three replications. The treatments consisted of two different rhizobacteria inoculant application methods (seed applied method and soil applied method) and three different periods of sowing after inoculation (0 min, 15 mins and 30 mins) in all possible combinations (six treatment The obtained results revealed that Bambara groundnut cultivated on soils fertilized with ten grams of rhizobacteria inoculant per planting hole significantly (p < 0.05) had highest vegetative growth, number of nodules per plant and yield traits in both planting season. The main effect of time of sowing indicated that plants sown 30 minutes after inoculation significantly (p < 0.05) gave the tallest plants and leaf area index per plant in 2015 and 2016 planting season than the other time regime. The interaction effect of rhizobacteria inoculant application methods and time of sowing after inoculation were observed to be significant (p < 0.05) in 2015 and 2016 planting season. The results showed that the plants on soil with combined use of soil applied method of inoculation treatment and 30 minutes after inocualtion before planting significantly (p < 0.05) had the highest vegetative growth, number of nodules per plant and yield parameters than the other interaction effect. The combined use of soil applied method of inoculation treatment and 30 minutes after inocualtion before planting is recommended for the cultivation of Bambara groundnut in Agbani Area South East Nigeria.
Integrating striga resistant maize and spatial arrangement of intercropped co...Innspub Net
Infestation of maize fields by Striga asiatica in coastal Kenya is increasing due to continuous mono-cropping of cereals without replenishment of soil nutrients, hence reducing land productivity. This may therefore lead to food insecurity if a viable solution is not found. A study was conducted to determine if integrating striga resistant maize and cowpea spatial arrangement could offer an effective solution to the striga problem. The study was conducted at KALRO Matuga in 2012 and 2013. A randomized complete block design, with three replications, was used. Maize varieties differed significantly in their stover yield in 2013 LR seasons but the varieties did not show any significant effect on striga stand counts in both seasons. Spatial arrangement of intercropped cowpea significantly influenced maize grain and stover yields in 2013 LR season. Maize variety V2 showed some tolerance
to striga weed. This variety is therefore recommended for multi-locational evaluation under the National Performance Trials (NPTs) to ascertain its superiority to the current commercial maize varieties (Coast Maize Composite, Pwani Hybrid 1 and Pwani Hybrid 4). Within row spatial arrangement of inter cropped cowpea gave higher maize yields than the between row arrangement. Farmers are therefore likely to realize improved maize yields by adopting the within row spatial arrangement of inter-cropped cowpea. Get the full articles at: http://www.innspub.net/volume-7-number-6-december-2015-ijaar/
Among the biotic stresses that affect cowpea (Vigna unguiculata L) productivity, infestation by cowpea bruchid beetles (Callosobruchus maculatus) is a major problem, causing yield losses of up to 100 %. To alleviate this problem, use of resistant varieties is a feasible approach for small-scale farmers. In Zambia, there are no reported sources of resistance to C. maculatus. The objectives of this study were: i) to evaluate certain cowpea mutants, generated at the University of Zambia, for resistance to C. maculatus; ii) to cluster the tested genotypes based on height, number of pods per plant, 100-seed weight, yield ha-1, number of eggs laid and adult emergence; and iii) to evaluate the candidate mutants for protein content. Experiments were conducted at three locations in 2014/15. The mutants, LT 11-5-2-2, BB 7-9-7-5 and BB-14-16-22, were found to be resistant to C. maculatus across locations and they out-performed their respective parents (p< 0.05) in the degree of resistance to C. maculatus. Cluster analysis, using selected agronomic parameters, showed that the selected resistant mutants (cluster B) were more similar to each other (95 %) than to Namuseba and Msandile (included as susceptible genotypes), which clustered at a similarity level of 78 % (cluster A). The mutants, LT 11-5-2-2, BB 7-9-7-5 and BB-14-16-22, showed resistance to C. maculatus, but their protein content was similar to their parents, indicating that this crucial trait had been maintained in the mutants.
Screening of Faba Bean (Vicia faba L.) Genotypes for Mycorrhizal Association ...Premier Publishers
Faba bean (Vicia faba L.) is one of the most important legumes used for food, feed and maintaining ecological balance. However, its productivity has been declining due to various biotic and abiotic factors. Arbuscular Mycorrhizal symbioses have been proved to enhance growth and yield responses of faba bean and other agricultural crops by counteracting these extreme factors. The study was conducted at field and greenhouse to evaluate the performance of faba bean genotypes for mycorrhizal colonization on two Phosphorus fertilizer levels. Randomized Complete Block Design with three replications was used. Analysis of variance indicated that all parameters, except number of mycorrhizal spores and relative mycorrhizal dependency, were highly significantly (p<0.01) varied for genotypes. Genotypes Wayu, Dosha, Didea, Moti and Tumsa for phosphorus fertilized; and Dagim, Gebelcho, Dosha, Tumsa and Wayu for unfertilized trial had performed better. Mycorrhizal colonization performance was higher on unfertilized than on P fertilized trial, at both field and greenhouse. Furthermore, for the genotypes tested at both conditions, the performance of the genotypes was higher at field than at greenhouse. The study also revealed that most of the mycorrhizal association parameters were highly correlated with biomass phosphorus uptake and grain yield of the faba bean genotypes.
Nodulation, Growth and Yield Response of Five Cowpea (Vigna unguiculata L. Wa...Premier Publishers
The experiment was carried out in the screen house of the Department of Crop, Soil & Pest Management, Federal University of Technology, Akure, Nigeria. The experimental layout was a 5 x 3 x 2 factorial combination with 3 replications given a total of 90 treatments. Seeds of five cowpea varieties namely: IT98K-205-8, Ife Brown, Oloyin Brown, IT98K-573-2-1 and IT96D-610 were sown in Plastic buckets of 7-liter capacity and were perforated at the bottom to allow for drainage and filled with top soil. Watering regimes of (500ml, 700ml and 900ml) were imposed and water was applied twice a week while cowpea plants were inoculated with 5g each of Rhizobia strain (Mesorhizobia loti) at seedling stage. Control set was maintained without inoculation. The effect of watering regimes on legume species was significant on nodulation, growth and yield characters of cowpea varieties evaluated. The results revealed marked varietal differences in plant growth, nodulation, yield and yield components. IT98K-573-2-1 and Oloyin Brown generally expressed superior performance in most measured parameters. Mesorhizobia inoculation significantly (p≤0.05) increased plant growth, nodulation, yield and yield components of cowpea. The interaction effect of variety, Mesorhizobia loti and watering regimes caused significant variations in the number of nodules, leaf area, number of seeds/pod and seed yield. The nitrogen and crude protein content in the leaf differed among the cowpea varieties evaluated. Application of mesorhizobium strain significantly increased seed yield of cowpea and caused substantial increase in nodulation and this subsequently affected the Nitrogen fixation potential of cowpea under varying soil moisture regimes.
Field experiments were conducted to investigate the variations in sixteen maize genotypes in relation to drought tolerance. The experimental set up was subjected to drought stress after five weeks of planting for three weeks before data on morphological and yield characters of maize genotypes were obtained for three cropping years. Plant height and grain yield of Bodija yellow maize were the highest overall. There was a significant difference among genotypes for drought stress resistance and Bodija yellow maize showed the most tolerance, while TZBR Comp 1 – C1 S2 510 genotype was the least. First principal component axis (Prin 1) had the highest contribution to the variation of the morphological, yield and drought tolerance traits. Prin 1 was highly related to the morphological and yield characters more than to the drought resistance. Plant height was negatively and strongly correlated (p<0.01) with stem height, number of leaves, stem girth, leaf length, leaf width and week after planting, but negatively correlated with the drought resistance. Therefore, Bodija yellow maize should be considered as parent material in breeding for the development of drought tolerant traits in maize.
Genetic control and heterosis depend directly on genetic divergence among the parents in generating promising hybrids
required by plant breeders. The purpose of this study was to determine the relative importance of heterosis, combining
abilities, regression and correlation estimates in order to develop hybrid cultivars in maize. The 28 F1 hybrids obtained by
partial diallel cross of 8 inbreds in a randomized complete block design were evaluated at the Lower Niger River Basin
Authority, Oke-Oyi, Nigeria in three years. General (GCA) and specific combining abilities (SCA) produced significant (P
< 0.01) effects for all the characters, while non-additive genetic effects were predominant. The levels of heterosis for grain
yield varied widely among crosses, ranging from -16.83 to 9.76%. Positive and significant genotypic and phenotypic
correlations among grain yield and some related characters (days to anthesis and silking; plant and ear heights; number of
ears plant-1 and 1000 seed weight) showed that each character could be used indirectly to selection of grain yield. These
results also indicated that SCA was more effective than heterosis for describing hybrid performance. The regression of
actual hybrid characters on the expected hybrid characters, based on parental GCA values, was highly significant.
Regression analysis also showed that all the agronomic characters jointly contributed 19.4% to grain yield of maize. The
inbreds (Pop 66 SR and 2000 EV DT-Y STRC4) and crosses (Pop 66 SR x, 2000 EV DT-Y STRC4, Pop 66 SR x KU1409
and 9006 x KU1409) featured prominently with respect to better GCA × Year and SCA × Year effects with high heterotic
values for maize grain yield and associated characters. These inbreds could serve as donors to obtain early and short
statured hybrids with higher yield, while the crosses may be exploited and adapted to the Nigerian Savannas. This study
also affirmed that genotypic and phenotypic correlation coefficients as well as combining abilities, heterosis and regression
analyses were found to be suitable models for yield improvement in maize breeding.
Development of drought tolerant maize cultivars is prerequisite to achieving stable grain yield in
drought–prone ecologies of Nigeria’s Guinea savanna. However, success has been limited mainly due
to lack of maize genotypes that show clear differences in response to well defined moisture deficit
condition. Two sets of drought tolerant (DT) maize germplasm were evaluated under screenhouse and
field conditions between 1999 and 2002. In the screenhouse study, performances of the genotypes
were compared under well-watered condition and moisture deficit imposed at different growth stages.
Under field conditions, the first set comprising 11 accessions along with a check were evaluated for 4
growing seasons while the second set which comprised 3 DT varieties were evaluated along with 2
check varieties using monthly plantings between April and August of 2001 and 2002, respectively. In
the first set, post anthesis moisture deficit significantly reduced grain yield by 25 to 73.5% in the open
pollinated varieties (OPVs) and by 20 to 64% in the hybrids. Grain yield under field conditions ranged
from 2.48 to 3.49, 2.82 to 3.73 and 3.58 to 4.76 tons/ha-1 for 1999, 2000 and 2001 full growing seasons,
respectively, and 2.03 to 2.50 tons/ha-1 for 2000 late growing season. In the second set, pre and post
anthesis moisture deficits reduced grain yield by 77.6 and 95.8%, respectively, of well watered
condition while in the field, grain yields in the genotypes were highest for plantings made in April and
July (1.90 - 2.5 t/ha), lowest for August (0.7 -1.8 t/ha) when moisture deficit coincided with
reproductive phase. Yield stability exhibited under moisture deficit and on the field by 8522-2, Oba
super 2 and AK9943-DMRSR in the first set as well as DT-SR-Y C0 and DT-SR-W C0 in the second set,
indicates their suitability either as cultivars per se or as potential source of DT alleles for
development of DT maize varieties for Nigeria’s savanna ecologies.
Pulses R & D in India by Dr. S K Datta, Deputy Director General, Indian Council of Agricultural Research. Presentation at The Pulses Conclave 2014 by India Pulse & Grains Association, IPGA
Effect of Different Weed Control Practices On Proximate Composition, Nutrient...IOSRJAVS
A field experiment was conducted during 2004 and 2005 cropping seasons to determine effect of different weed control practices on proximate composition, nutrient concentration and nutrient uptake of maize (Zea maysL.) at the Teaching and Research Farm of Ambrose Alli University, Ekpoma, Nigeria. Seven treatments were used for the experiment, viz no weeding (control), Primextra (3.0kg a.i./ha), mulching (wood shavings), one- hoe weeding at 3 weeks after planting (WAP), two hoe- weedings at 3 and 7 WAP, cover cropping with melon minus hoe-weeding, cover-cropping with melon plus one hoe-weeding at 3WAP. The seven treatments were laid out in randomized complete block design with four replicates. Results showed that mulched plot with wood shavings had the lowest weed density and highest proximate composition, grain nutrient concentration, ear leaf concentration and nutrient uptake followed by Primextra treated plot .The study recommends that small holder farmers to adopt mulching technique with wood shaving to improve the nutritional quality of maize grain since it does not involve any technical rigor besides signifying a non-chemical weed control.
Incidence and toxigenicity of fungi contaminating sorghum from NigeriaPremier Publishers
Each Agro ecological zone was transversely delineated into 5 districts and five villages (at least 20 Km from each other) called “locations” were selected in each district. In each district, Sorghum grains in stores, bunches in the field and sorghum grains in the market were sampled from five locations, each approximately 20 km from the previous sampling location. The mycological analytical procedures were performed under aseptic condition. Plates were counted for fungal colonies using a colony counter and the number of fungal colonies per gram of sample was calculated as CFU/g. The fungi species were isolated and subsequently identified using MEA/CYA media for Aspergillus and Penicillium species and PDA for the fusarium species Toxigenicity studies on strains representing species of Aspergillus, Penicillium, Fusarium was carried out to determine their ability to produce aflatoxin B1 (AFB1); aflatoxin B2 (AFB2); aflatoxin G1 (AFG1); aflatoxin G2 (AFG2); OTA, ZEN, DON and FB1. A total of 701 isolates were recorded which consist of 67 confirmed fungal strains. Aspergillus species formed the majority with 346(49.6%) followed by the Fusarium species with 186(26.7%) then Penicillium species with 102(14.6%) while others such as Cuvularia, Phoma, Alternaria, Rhizormucor constitutes 67 (9.0% )strains of the total population.
Study on Distribution of Microbial and Diazotrophic Azotobacter Population in...Agriculture Journal IJOEAR
Abstract— The current scenario encounters the steady demand of food supply and the application of fertilizer is become an indispensable in modern agriculture. Hence, the present study is focused on distribution of microbial and diazotrophic Azotobacter population in rhizosphere soil sample. Total microbial population viz, bacteria, fungi, actiomycetes and diazotrophic Azotobacter were enumerated from five different rhizosphere soil samples and compared the distribution of diazotrophic Azotobacter with other three microbial groups. The results of enumeration of total microbial population reveals that comparatively the bacterial population found to be higher followed by Azotobacter population in various rhizosphere soil. Based on the predominant growth, five Azotobacter strains (one isolate from each sample) were isolated and authenticated through morphological and biochemical characteristics.
Impacts of Plant Growth Promoting Rhizobacteria Inoculation Configurations on...AI Publications
The main objective of this study is determine the responses of Bambara groundnut [Vigna subterranea (L). Verdc.] to application methods of plant growth promoting rhizobacteria inoculant and time of sowing after inoculation in Agbani area of Enugu, South East Nigeria. Field trials were conducted at the Teaching and Research Farm of the Faculty of Agriculture and Natural Resources management, Enugu State University of Science and Technology in 2015 and 2016 planting season. The experiment was a 2 × 3 factorial trial in a randomized complete block design with three replications. The treatments consisted of two different rhizobacteria inoculant application methods (seed applied method and soil applied method) and three different periods of sowing after inoculation (0 min, 15 mins and 30 mins) in all possible combinations (six treatment The obtained results revealed that Bambara groundnut cultivated on soils fertilized with ten grams of rhizobacteria inoculant per planting hole significantly (p < 0.05) had highest vegetative growth, number of nodules per plant and yield traits in both planting season. The main effect of time of sowing indicated that plants sown 30 minutes after inoculation significantly (p < 0.05) gave the tallest plants and leaf area index per plant in 2015 and 2016 planting season than the other time regime. The interaction effect of rhizobacteria inoculant application methods and time of sowing after inoculation were observed to be significant (p < 0.05) in 2015 and 2016 planting season. The results showed that the plants on soil with combined use of soil applied method of inoculation treatment and 30 minutes after inocualtion before planting significantly (p < 0.05) had the highest vegetative growth, number of nodules per plant and yield parameters than the other interaction effect. The combined use of soil applied method of inoculation treatment and 30 minutes after inocualtion before planting is recommended for the cultivation of Bambara groundnut in Agbani Area South East Nigeria.
Integrating striga resistant maize and spatial arrangement of intercropped co...Innspub Net
Infestation of maize fields by Striga asiatica in coastal Kenya is increasing due to continuous mono-cropping of cereals without replenishment of soil nutrients, hence reducing land productivity. This may therefore lead to food insecurity if a viable solution is not found. A study was conducted to determine if integrating striga resistant maize and cowpea spatial arrangement could offer an effective solution to the striga problem. The study was conducted at KALRO Matuga in 2012 and 2013. A randomized complete block design, with three replications, was used. Maize varieties differed significantly in their stover yield in 2013 LR seasons but the varieties did not show any significant effect on striga stand counts in both seasons. Spatial arrangement of intercropped cowpea significantly influenced maize grain and stover yields in 2013 LR season. Maize variety V2 showed some tolerance
to striga weed. This variety is therefore recommended for multi-locational evaluation under the National Performance Trials (NPTs) to ascertain its superiority to the current commercial maize varieties (Coast Maize Composite, Pwani Hybrid 1 and Pwani Hybrid 4). Within row spatial arrangement of inter cropped cowpea gave higher maize yields than the between row arrangement. Farmers are therefore likely to realize improved maize yields by adopting the within row spatial arrangement of inter-cropped cowpea. Get the full articles at: http://www.innspub.net/volume-7-number-6-december-2015-ijaar/
Among the biotic stresses that affect cowpea (Vigna unguiculata L) productivity, infestation by cowpea bruchid beetles (Callosobruchus maculatus) is a major problem, causing yield losses of up to 100 %. To alleviate this problem, use of resistant varieties is a feasible approach for small-scale farmers. In Zambia, there are no reported sources of resistance to C. maculatus. The objectives of this study were: i) to evaluate certain cowpea mutants, generated at the University of Zambia, for resistance to C. maculatus; ii) to cluster the tested genotypes based on height, number of pods per plant, 100-seed weight, yield ha-1, number of eggs laid and adult emergence; and iii) to evaluate the candidate mutants for protein content. Experiments were conducted at three locations in 2014/15. The mutants, LT 11-5-2-2, BB 7-9-7-5 and BB-14-16-22, were found to be resistant to C. maculatus across locations and they out-performed their respective parents (p< 0.05) in the degree of resistance to C. maculatus. Cluster analysis, using selected agronomic parameters, showed that the selected resistant mutants (cluster B) were more similar to each other (95 %) than to Namuseba and Msandile (included as susceptible genotypes), which clustered at a similarity level of 78 % (cluster A). The mutants, LT 11-5-2-2, BB 7-9-7-5 and BB-14-16-22, showed resistance to C. maculatus, but their protein content was similar to their parents, indicating that this crucial trait had been maintained in the mutants.
Screening of Faba Bean (Vicia faba L.) Genotypes for Mycorrhizal Association ...Premier Publishers
Faba bean (Vicia faba L.) is one of the most important legumes used for food, feed and maintaining ecological balance. However, its productivity has been declining due to various biotic and abiotic factors. Arbuscular Mycorrhizal symbioses have been proved to enhance growth and yield responses of faba bean and other agricultural crops by counteracting these extreme factors. The study was conducted at field and greenhouse to evaluate the performance of faba bean genotypes for mycorrhizal colonization on two Phosphorus fertilizer levels. Randomized Complete Block Design with three replications was used. Analysis of variance indicated that all parameters, except number of mycorrhizal spores and relative mycorrhizal dependency, were highly significantly (p<0.01) varied for genotypes. Genotypes Wayu, Dosha, Didea, Moti and Tumsa for phosphorus fertilized; and Dagim, Gebelcho, Dosha, Tumsa and Wayu for unfertilized trial had performed better. Mycorrhizal colonization performance was higher on unfertilized than on P fertilized trial, at both field and greenhouse. Furthermore, for the genotypes tested at both conditions, the performance of the genotypes was higher at field than at greenhouse. The study also revealed that most of the mycorrhizal association parameters were highly correlated with biomass phosphorus uptake and grain yield of the faba bean genotypes.
Nodulation, Growth and Yield Response of Five Cowpea (Vigna unguiculata L. Wa...Premier Publishers
The experiment was carried out in the screen house of the Department of Crop, Soil & Pest Management, Federal University of Technology, Akure, Nigeria. The experimental layout was a 5 x 3 x 2 factorial combination with 3 replications given a total of 90 treatments. Seeds of five cowpea varieties namely: IT98K-205-8, Ife Brown, Oloyin Brown, IT98K-573-2-1 and IT96D-610 were sown in Plastic buckets of 7-liter capacity and were perforated at the bottom to allow for drainage and filled with top soil. Watering regimes of (500ml, 700ml and 900ml) were imposed and water was applied twice a week while cowpea plants were inoculated with 5g each of Rhizobia strain (Mesorhizobia loti) at seedling stage. Control set was maintained without inoculation. The effect of watering regimes on legume species was significant on nodulation, growth and yield characters of cowpea varieties evaluated. The results revealed marked varietal differences in plant growth, nodulation, yield and yield components. IT98K-573-2-1 and Oloyin Brown generally expressed superior performance in most measured parameters. Mesorhizobia inoculation significantly (p≤0.05) increased plant growth, nodulation, yield and yield components of cowpea. The interaction effect of variety, Mesorhizobia loti and watering regimes caused significant variations in the number of nodules, leaf area, number of seeds/pod and seed yield. The nitrogen and crude protein content in the leaf differed among the cowpea varieties evaluated. Application of mesorhizobium strain significantly increased seed yield of cowpea and caused substantial increase in nodulation and this subsequently affected the Nitrogen fixation potential of cowpea under varying soil moisture regimes.
The morpho-agronomic characterization study of Lens culinaris germplasm under...Shujaul Mulk Khan
The present research study evaluate and identify the most suitable and high yielding genotypes of Lens culinaris for the salt marsh habitat of Swat in moist temperate sort of agro climatic environment of Pakistan. A total of fourteen genotypes were cultivated and analyzed through Randomized Complete Block Design (RCBD). These genotypes were AZRC-4, NL-2, NL4, NL-5, NL-6, NARC-11-1, NARC-11-2, NARC-11-3, NARC-11-4, 09503, 09505, 09506, P.Masoor-09 and Markaz-09. Different parameters i.e., germination rate, flowering, physiological maturity, plant height, biological grain yield, seed weight, pods formation and its height, pods per plants and protein content were focused specially throughout the study. Preliminary the Lentil genotypes have significant variability in all the major morpho-agronomic traits. The days to germination, 50% flowering and 100 seed weight ranged from 7 to 9, 110 to 116 days, and from 5.4 to 7.3 gm respectively. Biological yield and grain yield ranged from 5333 to 9777 kg ha−1 and 1933 to 3655 kg ha−1 respectively. Whereas, protein contents ranged from 23.21% to 28.45%. It was concluded that the genotype AZRC-4 is better varity in terms of grain yield plus in 100 seed weight and moreover, 09506 genotype was significant under salt marsh habitat in early maturing for the Swat Valley, Pakistan.
Assessment of forage corn quality intercropping with green beans under influe...Innspub Net
To assess the quality of forage corn intercropping with green beans under the influence of Rhizobium bacteria and Arbuscular Mycorrhizal fungus, make a test in educational-research farm of agriculture faulty of Azna PNU that it was design in factorial to randomized complete block with three replications. The experimental factors include cropping systems such as mono cropping of corn, mono cropping of green beans, intercropping, Arbuscular Mycorrhizal fungus (use and non-use) and Rhizobium bacteria (use and non-use). The results showed that cropping systems on crude protein, wet forage weight, dry forage weight were significant at 1% level as well as leaf to stem ratio was significant at 5% level. Between different levels of bacteria used, acid detergent fiber was impressed and was significant at 5% level. Arbuscular Mycorrhizal fungus was significant at 5% level on water soluble carbohydrate. The results showed that the use of separate and combined of Rhizobium bacteria and Arbuscular Mycorrhizal fungus increase the quality of corn in intercropping than mono cropping. Finally with increasing of plant diversity and microorganism in soil increased the quality and quantity of forage. Get the full articles at: http://www.innspub.net/volume-6-number-5-may-2015-jbes/
Isolation, identification of antagonistic rhizobacterial strains obtained fro...Shazia Shahzaman
Plant growth promoting rhizobacteria (PGPR), are associated with roots, found in the rhizosphere and can directly or indirectly enhance the plant growth. In this study soil was collected from rhizosphere of chickpea fields of different areas of Rawalpindi division of Pakistan. PGPR were isolated, screened and characterized. Eight isolates of rhizobacteria (RHA, RPG, RFJ, RC, RTR, RT and RK) were isolated from Rawalpindi division and were characterized. The antagonistic activity of these PGPR isolates against root infecting fungi (Fusarium oxysporum and Verticillium spp.,) was done and production of indole acetic acid (IAA), siderophore and P-solubilization was evaluated. The isolates RHA, RPG, RFJ, RC, RRD and RT were found to be positive in producing siderophore, IAA and P-solubilization. Furthermore, most of the isolates showed antifungal activity against Fusarium oxysporum, and Verticillium spp. The rhizobacterial isolates RHA, RPG, RFJ, RC, RRD, RTR, RT and RK were used as bio-inoculants that might be beneficial for chickpea cultivation as the rhizobacterial isolates possessed the plant growth promoting characters i.e. siderophore, IAA production, phosphate solubilization. In in vitro tests, Pseudomonas sp. and Bacillus spp. inhibited the mycelial growth of the fungal root pathogens. The isolates (RHA and RPG) also significantly increased (60-70%) seed germination, shoot length, root length of the chickpea. The incidence of fungi was reduced by the colonization of RHA and RPG which enhanced the seedling vigor index and seed germination. The observations revealed that isolates RHA and RPG is quite effective to reduce the fungal root infection in greenhouse, and also increases seed yields significantly. These rhizobacterial isolates appear to be efficient yield increasing as well as effective biocontrol agent against fungal root pathogen.
Hidden diversity for abiotic and biotic stress tolerances in the primary gene...FOODCROPS
FOODCROPS.VN. Hidden diversity for abiotic and biotic stress tolerances
in the primary gene pool of rice revealed by a large
backcross breeding program
Impact of Untreated Brewery Effluent on Bacteriological Characteristic of Agr...ijtsrd
This research was conducted to evaluate the impact of untreated brewery effluent on the bacteriological characteristic of agricultural soil. This is to ascertain the suitability of untreated brewery effluent for irrigation purposes. Untreated brewery effluent was aseptically collected from Intafact brewery, Onitsha, Anambra State, Nigeria., while agricultural soil was obtained from a maize farm in Onitsha. Five kilograms of the soil sample was treated with 200 ml of the effluent in a pot experiment and allowed for 80 days. The bacteriological characteristic of the effluent and soil samples treated and untreated was determined by estimating the total bacterial count, total coliform count, fecal coliform count, Pseudomonas count, Rhizobial count and Clostridium count. Results obtained showed that the untreated brewery effluent had total bacterial count of 5.2 × 103cfu ml, total coliform count of 0.5× 103cfu ml, Pseudomonas count of 0.7 × 103cfu g and zero fecal coliform, Rhizobium and Clostridium counts. The total bacterial count, total coliform count, Pseudomonas count, rhizobial count and Clostridium count for the untreated and treated soil samples were 10.8× 103cfu g and 22.8× 103cfu g, 7.2× 103cfu g and 11.4× 103cfu g, 0.9 × 103cfu g and 2.5 × 103cfu g, 0.4× 103cfu g and 0.73× 103cfu g, 1.2 × 103cfu g and 8.0 × 103cfu g respectively. A total of 34 bacterial organisms belonging to ten different genera Pseudomonas, Bacillus, Azotobacter, Streptococcus, Staphylococcus, Rhizobium, Proteus, Enterobacter, Klebsiella and Serratia were isolated from all the samples analyzed. While Enterobacter sp. occurred most in the effluent sample, Bacillussp predominated in the untreated soil sample. Rhizobium and Pseudomonas count were significantly higher p value 0.05 in the treated soil sample. This study showed that untreated brewery effluent enhanced the growth of plant growth promoting bacteria, hence, can serve efficiently as irrigation water. Mbonu, C. F. | Onuorah, S. C. | Okoye, E. C. S. "Impact of Untreated Brewery Effluent on Bacteriological Characteristic of Agricultural Soil" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-3 , April 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49673.pdf Paper URL: https://www.ijtsrd.com/biological-science/microbiology/49673/impact-of-untreated-brewery-effluent-on-bacteriological-characteristic-of-agricultural-soil/mbonu-c-f
Phosphate solubilizing potential of Rhizobium and Bacillus species for enhanc...Innspub Net
By International Network For Natural Sciences INNSPUB in Agronomy and Horticulture.
A field experiment was conducted to evaluate the separate and integrated effect of Rhizobium and Bacillus spp. on the growth of maize (Zea Mays L.). Inocula of Rhizobium and Bacillus were applied as seed coating. Recommended dose of fertilizer (120-60 kg NP ha-1) was applied at sowing. The treatments were implied according to Randomized Complete Block Design with three repeats. Inoculation had no significant effect on the leaf length (84cm) and internodal distance (18.3cm) compared to their respective control (80cm and16.5cm) but the photosynthetic rate (105.3μ mol-2s-1) , transpiration rate (13.2 mmolm-2s-1), plant height (259.3cm), leaf width (7.7cm), stem diameter (15.43mm), leaf area (644cm-2) and shoot fresh weight (79.6 tones ha-1) were significantly improved by co-inoculation. Effect of Bacillus was statistically at par with co-inoculation regarding transpiration rate (11.47 m mol m-2s-1), plant height (249.3 cm) and stem diameter (14.87 mm). Response of leaf width, stem diameter, leaf area and shoot fresh weight were significantly higher by Rhizobium application compared to the Bacillus inoculation, however, positive influence was observed by all the inoculation treatments over the control.These findings indicated that inoculation of Rhizobium and Bacillus has positive effect on the maize growth and their co-inoculation (Rhizobium+ Bacillus) showed more pronounced results. Get the full articles at: http://www.innspub.net/volume-4-number-1-january-2014-2/
Influence of mineral and organic fertilization on some agronomic parameters o...Open Access Research Paper
This study evaluated the effect of mineral and organic fertilization on some agronomic parameters of cassava nursery plants Bocou 1 and Yavo (Manihot esculenta Crantz). For this purpose, 1200 cassava plants were produced on 10 substrates based on soil supplemented with chicken droppings, sawdust, carbonized rice husks and NPK 10 18 18. The trial was conducted in a completely randomized Fisher block design on two 880 m2 subplots 6 m apart. The planting density was 1 m x 1 m with three replications per treatment, i.e. 600 plants per cassava variety. The manures used were chicken manure, charred rice husks and NPK 10-18. Results showed that treatments T2S6 (T2: Carbonized rice husks; S6: Substrate 6) and T2S3 (T2: Carbonized rice husks; S3: Substrate 3) induced better plant growth than the other treatments for the two cassava varieties studied. The highest yields were obtained with treatments T3S2 (T3: NPK 10 18 18; S2: Substrate 2) (456.83 t/ha) and T2S8 (T2: Carbonized rice husks; S8: Substrate 8) (423.25 t/ha) at Bocou 1 and Yavo, respectively. The results of this study will help optimize cassava production in Côte d’Ivoire and improve the purchasing power and livings standard of producers.
A comparative study on the response of six maize hybrids: two
hybrids each from the 1980s (8321-21 and 8425-8), 1990s (9801-11 and 9803-2)
and 2000s (0103-11 and 0103-15) to sub-optimal and optimal nitrogen fertilization
was conducted in Oke-Oyi, Nigeria. The trials were set up in a split plot with three
nitrogen levels (0, 30 and 90 kg N ha-1) as a main plot and six hybrids as sub-plots.
Significant interactions were observed between hybrid and N level for all
characters, with increasing in variation as the level of N decreased. Mean grain
yield reductions across eras were 73.8% at no-N and 32.6% at low-N, and those of
optimal-N fertilization were 34.3% and 15.7% for 1980s and 1990s genotypes
respectively. Depending on N treatment, grain yield varied from 0.67 to 4.89 t ha-1.
Kernel number was most severely reduced by N stress, but had positive and highly
significant (p≤0.01) correlation with grain yield at all N levels. Genetic gains in
grain yield were 42% (between 1980 and 2000 eras) and 9% (between 1990 and
2000 eras) under optimal-N fertilization. The two modern hybrids of 2000 era
(0103-11 and 0103-15) were outstanding for all the agronomic traits and leaf
chlorophyll concentration at all N levels. Improving traits associated with fertilizer
N response could accelerate rate of genetic gains in maize yields.
Effect of nitrogen and phosphorus amendment on the yield of a Chlorella sp. s...Agriculture Journal IJOEAR
Abstract— A strain of microalgae was isolated from phytoplankton samples collected from the sea coast of Amsheet, North Lebanon. Molecular diagnosis based on ribosomal RNA genes showed it to be most closely related to Chlorella sp. (GenBank accession KC188335.1) with over 90 % nucleotide identity. It was then evaluated whether N and P amendments of seawater fertilized with Guillard’s f/2 medium would improve algal growth and production. Addition of nitrogen (30 ppm) and/or phosphorus (2 ppm) to microalgae grown under laboratory conditions in 3L bioreactors resulted in improved biomass yield (mg dry matter/ L) by approximately 48%, and increased protein yield by approximately 56%, from 19.5% to 30.6% of DM content. Total protein yield/L of culture medium was therefore increased by approximately 83%. Total lipid content and carotenoid levels of the microalgal culture were not affected by the N+P amendement, whereas chlorophyll content was almost doubled. When lower levels of N+P supplementations, 10 and 20 ppm N, were tried, the biomass yield was also improved. The experiment was repeated in 20 L bioreactors in a plastic greenhouse, under normal environmental conditions, with an average temperature of 28°C and a maximum temperature of 36°C. At these relatively high temperatures, the growth rate was slowed down, but N supplementations at 10 and 20 ppm resulted in improved dry matter yield by 25 and 45% respectively, and protein content by 17 and 35%, respectively. Knowledge of the optimal culturing conditions of this local Chlorella strain is essential for its efficient production and is expected to serve future environmental and biotechnological purposes.
Microbiological and Physicochemical Assessment of Poultry Soil Samples in Aku...Agriculture Journal IJOEAR
Abstract— Human activities such as animal production in many parts of the world, still impact negatively on the environment and biodiversity. This study was carried out to assess the microbiological and physicochemical parameters of poultry soil samples. Soil samples were collected from different poultry in Akure metropolis and soil samples from Federal University of Technology, Akure (FUTA) environment as control. Microbiological and physicochemical analyses were carried out using standard methods. The mean total viable bacterial count of poultry soil ranged from 9.02±0.511×105cfu/g in sample site A to 11.2±0.021×105cfu/g in sample site B and there were significant difference (p<0.05) between the bacterial count of poultry soil and control, mean highest fungal load is 6.05±0.301× 103sfu/g. Bacteria isolated were Escherichia coli, Aeromonas hydrophila ,Bacilllus subtilis, Bacillus cereus, Klebsiella pneumonia, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus and Streptococcus faecium. Escherichia coli had the highest occurrence of 23.08% while Aeromonas hydrophila had the lowest occurrence of 5.13%. Fungi isolated were Aspergillus flavus, Aspergillus niger, Aspergillus fumigates and Saccharomyces species. Aspergillus niger 46.67% had the highest occurrence while Saccharomyces species had the lowest occurrence of 13.33%. Physiochemical analysis showed that poultry soil had mean pH, temperature and Organic Carbon of 7.92±0.34, 34±0.04oC and 14.88±0.56% respectively, Organic Matter is 5.50±0.61%, Nitrogen 1.27±0.03 mg/g, Phosphorus58.92±0.01 mg/g, Potassium55.48±0.23 mg/g, Sodium 41.77±0.91mg/g, Calcium 28.70±0.24mg/g, Magnesium 20.65±0.32 mg/g and Cation exchange capacity146.60±0.11%. The results obtained calls for proper discharge of poultry waste into the environment to prevent transmission of diseases by water borne pathogens.
Effect of cattle manure and inorganic fertilizer on the growth and yield of h...Premier Publishers
The high cost of inorganic fertilizer and continuous decline in soil fertility results to low crop yield hence, the need to supplement mineral fertilizer with organic manure. Field experiments were conducted in 2013 and 2014 cropping seasons at the Teaching and Research Farm, Abubakar Tafawa Balewa University, Gubi, Bauchi State, Nigeria, to investigate the effects of different levels of cattle manure, CM, (0, 5 and 10 t/ha) and NPK (0, 200 and 400kg/ha) on the growth, yield and yield components of hybrid maize (Zea mays L.). These treatment combinations were replicated three times in a randomized complete block design. CM levels had significant effect (P≤0.05) on number of leaves per plant and plant height. However, NPK levels also had significant effect on many characters in both 2013 and 2014 but lower mean values were recorded in 2013. In 2014, significant interactions were observed in mean number of leaves, plant height, husk weight and yield (t/ha). The highest seed yield (5.65t/ha) was obtained when 5t/ha CM was used, which was statistically similar (5.60t/ha) to 400kg/ha inorganic fertilizer used. The application of 5t/ha CM or 400kg/ha NPK is recommended for improved production of hybrid maize in the study area.
Similar to Agoyi, E.E., Afutu, E. et al 2016 Screening soybean genotypes for promiscuous symbiotic association with Bradyrhizobium strains (20)
2. E.E. AGOYI et al.50
de nodules, et 50% de nodules actives. Une corrélation positivement très significative a été observée entre poids
sec et nombre de nodules. Cette étude propose les accessions NamII, WonderSoya, Bulindi 48C, NamSoy 4M,
MakSoy 3N, NamSoy 3, K-Local, Kabanyolo 1, UG 5, Soprano, MakSoy 2N, and MakSoy 5N comme potentiels
parents à utiliser dans un programme ultérieur d’amélioration génétique.
Mots Clés: Glycine max, nodules, nodulation facile, Uganda
INTRODUCTION
Soybean (Glycine max L. Merrill) is an important
nodulating legume crop, with potential for
expansion inAfrica. Globally, soybean accounts
for about 84.5% of the grain legumes trade (Abate
et al., 2011). Statistics from FAOSTAT (2013),
showed low soybean productivity in Africa, at
2.2 million metric tonnes from 1.8 million ha. The
average soybean yield in Africa is 1,254 kg ha-1
,
which is 50% of the global average at 2,475 kg
ha-1
in the world (FAOSTAT, 2013). This may be
attributed to the use of low yielding varieties,
low soil fertility, pests and diseases among other
factors.
Soybean is mainly used as a source of protein
in human food and animal feeds. The protein
content in soybean is approximately 40% (Tefera,
2011). The crop requires high doses of nitrogen,
mostly at pod filling stage (Machido et al., 2011)
in order to construct a high concentration of
proteins in the grain. Soybean requires
approximately 80 kg of nitrogen for each metric
tonne of grain yield. Salvagotti et al. (2008) noted
that soybean crops that yield 5 t ha-1
, take up
about 400 kg of nitrogen, with average of 58%
coming from N2
fixation.
As a legume, soybean has the capacity to fix
a large quantity of atmospheric N2
, in symbiotic
association with Bradyrhizobia (Anuar et al.,
1995; Peoples et al., 1995). Summary statistics
for controlled experiments reported by Salvagotti
et al. (2008), showed that soybean can fix up to
337 kg of nitrogen per hectare when inoculated
with effective strains of Bradyrhizobium. Many
soybean varieties are highly specific, such that
most cultivars nodulate only with
Bradyrhizobium japonium for biological nitrogen
fixation (Sanginga et al., 1997).
Bradyrhizobium japonicum populations
required for effective nodulation of soybeans are
not endemic to African soils (Hadley and
Hymowitz, 1973). For this reason, artificial
Biological Nitrogen Fixation (BNF), using
introduced Bradyrhizobium strains has been the
practice to improveAfrica’s soybean production,
though with several limitations. Some of the
factors that lead to failure in maximising
nodulation potential of soybean include
unfavourable storage conditions (Keyser et al.,
1993), disparity between cultivars (Machido et
al., 2011) and competition between indigenous
and introduced strains (Ge and Xu, 1982). Other
factors include phosphorus deficiency that is
widespread in Sub-Saharan African soils
(Sanginga et al., 1995; Sanchez et al., 1997), non-
availability of commercial B. japonicum
inoculants (Tefera, 2011), lack of effective
transportation and distribution systems of
inoculants, and lack of programmes to teach
farmers how to use BNF (Kueneman et al., 1984).
To circumvent this situation, Scientists at the
International Institute of Tropical Agriculture
(IITA) developed promiscuous soybean cultivars
that are able to nodulate with indigenous and
readily available Bradyrhizobium strains. They
have released soybean lines which are
promiscuous in the sense that these lines form
nodules with indigenous bacteria, presumably
strains of Bradyrhizobium spp. which form
symbiotic nodules with cowpea (IITA, 1996).
Relatedly, Abaidoo et al. (2000) detected
Bradyrhizobium spp. populations in
approximately 74% of theAfrican soils.
This study aimed at screening soybean lines
for their ability to effectively nodulate with
Bradyrhizobium spp., thus having potential for
use as parental lines to initiate a breeding
programme for the development of improved
promiscuous soybean cultivars for higher yields
inAfrica.
3. Screening soybean genotypes for promiscuous symbiotic association 51
MATERIALS AND METHODS
Planting material and design. Sixty five soybean
genotypes from different origins (IITA (3),
Zimbabwe(8),AVRDC(20),USA(7),Uganda(25)
and others (2) were evaluated in this study in a
greenhouse at Makerere University Agricultural
Research Institute, Kabanyolo (MUARIK). Each
of the 65 genotypes was inoculated with (i)
cowpea-type inoculant (Bradyrhizobium sp.
strain USDA 3456), (ii) soybean-type inoculant
(Bradyrhizobium Japonicum strain; USDA 110)
and iii) a control without inoculant, and grown
on steam-sterilised normal soil in a completely
randomised design with three replicates.
Soil media preparation. Top soil used in this
study was collected from a cultivated field at
MUARIK. Soil sub-samples were analysed for
pH, organic carbon, total nitrogen, Bray 1
extractable phosphorus and exchangeable bases
(K+
, Na, Mg2+
and Ca3+
) using procedures
described in Okalebo et al. (2002). Soil analysis
was done to check for suitability in terms of poor
to moderate nitrogen content (<0.2%) (Table 1).
The soil was then steam-sterilised at 120 °C
for six hours, under direct hot steam, and left to
cool over 24 hours. Steam-sterilisation was done
using a drum containing water in its lower
compartment. The water was boiled and produced
vapour, which passed through the soil in the top
chamber in order to kill microorganisms. The
sterilised soil was used to fill 585 buckets, each
of five kilogrammes capacity (20.0 cm diameter
and 20.5 cm depth) that were lightly perforated at
the bottom to aerate and avoid water lodging.
The soil was pre-mixed with 0.0356 and 0.036 g of
TSP (Triple Super Phosphate) and Muriate of
Potash (MOP), respectively per kg of soil,
representing 20 kg of phosphorus and 40 kg of
potassium per hectare. Sufficient P and K are
essential for biological nitrogen fixation
processes in earlier studies (Giller et al., 1997),
and these nutrients were deficient in the study
soil (Table 1).
Preparation of inoculum. Rhizobia inoculants
were obtained from Biofix (Kenya), purified and
incubated in Soil Science Biological Nitrogen
Fixation (BNF) laboratory at Makerere University.
TABLE1.Laboratoryresultsofsoilsamplesanalysis
SamplespH(H2
0)SOM(%)TotalN(%)Bray1extractableK+(cmolkg-1
)Na+
(cmolkg-1
)Ca+(cmolkg-1
)
P(mgkg-1
)
Sample15.322.800.227.955.440.335.25
Sample25.531.540.134.704.420.355.50
Sample35.552.300.227.415.440.434.50
Criticalvalues5.5-6.530.215---
SOM=soilorganicmatter
4. E.E. AGOYI et al.52
The strains, Bradyrhizobium japonicum strain
USDA 110 (soybean-type) and Bradyrhizobium
sp. strain USDA 3456 (cowpea-type), were grown
to 7.91 x 109
cells g-1
for cowpea-type rhizobium
and 9.08 x 109
cells g-1
for soybean-type rhizobium.
These were formulated into an inoculum carried
in steam-sterilised peat soil. Two table spoonfuls
of sugar were dissolved into 300 ml of clean luke-
warm water, in a soda bottle, to be used as sticker.
The inoculant was mixed with the sticker and
directly applied on seeds to enhance association
of plant-rhizobium.
Planting, data collection.About ten seeds were
sown in each bucket and thinned to 3 plants after
germination. Planting was first done for non-
inoculated seeds to avoid contamination. Six
weeks after germination, buckets were soaked in
water and carefully inverted to release the
aggregate plants-soil medium. The aggregate
was carefully washed abundantly with water to
separate the soybean plants from the soil medium,
without breaking the roots, or loosing nodules.
Roots were then rinsed and wrapped in tissue
paper to reduce wetness. With reference to
Shiraiwa et al. (1994), who reported positive
correlation between nodule dry weight (NDW)
and N2
fixation in soybean, all nodules were
harvested and counted to determine the number
of nodules (NN), and later weighed to determine
the fresh weight of nodules per plant (NFW)
using high precision digital scale ADAM Pow
453e (Max 450 g, d = 0.001 g). Thereafter, all the
nodules were split, open to assess effectiveness
and percentages of effective nodules (NE) were
generated per plant, based on the presence of
pink pigmentation inside nodules, an indicator
of effectiveness. Thereafter, nodules were oven
dried at 65 °C for four days (Gwata et al. 2004),
and weighed to determine the total nodules dry
weigh (NDW) per plant.
Data analysis. A Linear Mixed Model (LMM)
was used to analyse data. A mixed model
approach was used in this study so as to allow
the modeling of different variance-covariance
structure that could not be handled using the
traditional analysis of variance. Instead of
assuming that error variance was constant, we
allowed each genotype and Rhizobia level to have
a different variance. Our model (see below) was
fitted using GenStat 14th
edition (VSN
International Ltd, Hemel Hempstead, UK) (Payne
et al., 2011):
Where:
= observation from the kth
replicated of ith
genotype inoculated with jth
Rhizobia strain; =
overall mean; = the effect of the ith
genotype;
= the effect of the jth
Rhizobia strain; =
the interaction between the ith
genotype and jth
Rhizobia strain and is random error.
In the above model specification, variances
were assumed equal for replicates (identity) and
unequal for type of Bradyrhizobium and
genotypes (diagonal). The changes in deviances
and degrees of freedom were used to compare
models to avoid over-ride uselessly GenStat and
fit the best model (O’Neill, 2010).
Correlations between couples of parameters
(nodule number, percentage of effective nodules,
fresh weight of nodules, and dry weight of
nodules) were tested for each treatment.
The best performing genotypes were selected
based on three inclusive criteria:
(i) genotypes with a minimum of 10 nodules per
plant (referring to the scale of Corbin et al.
(1977))
(ii) genotypes with over 50 mg average nodule
dry weight (Gwata, 2004); and
(iii) genotypes with a minimum of 50% effective
nodules.
Using the above criteria, 12 genotypes were
selected as responsive to Bradyrhizobium Sp.
Strain USDA 3456 (cowpea-type inoculant),
hence ‘promiscuous’ (Table 2). Using the same
criteria, 25 genotypes were responsive to
Bradyrhizobium japonicum Strain USDA 110
(soybean-type inoculant) (Table 3). Genotypes
were ranked based on their total nodule dry weight
under Bradyrhizobium strains.
5. Screening soybean genotypes for promiscuous symbiotic association 53
RESULTS
The Wald tests for fixed effects, showed highly
significant main effects for Rhizobium strain and
genotypes, as well as the interaction between
genotypes and Rhizobium strain (P<0.001) for all
the variables measured (Table 2).
The 12 genotypes responsive to
Bradyrhizobium sp. Strain USDA 3456 were
dominated by local (Ugandan bred) soybean
varieties (Table 3). These highly responsive
genotypes had between 11 and 42 nodules per
plant, of which 56.6 to 82.65%, respectively were
effective. Nodule fresh weight ranged between
113.2 and 414.7 mg per plant, with nodule dry
weight of 54.83 to 149.78 mg per plant. Genotype
Wondersoya from IITAwas the most responsive,
having 40 nodules per plant, of which 85.84%
were effective and had both the highest fresh
and dry nodules weights of 414.7 and 149.7 mg,
respectively. Ten of the twelve responsive
genotypes were of tropical origin. They were
either locally bred varieties in Uganda (NamSoy
4M, MakSoy 3N, NamSoy 3, Kabanyolo 1,
MakSoy 2N, MakSoy 5N, Bulindi 48C), bred and
released by IITA (NamII, WonderSoya), or from
Zimbabwe (Soprano); and the two others from
unknown origin (K-local and UG5). Thus, about
18.5% of the currently assessed germplasm were
promiscuous, with genotypes from tropical
origins were more promiscuous (Table 3). None
of the genotypes from USA or AVRDC were
responsive to the indigenous rhizobium strain,
Bradyrhizobium sp. strain USDA 3456. The least
responsive genotypes included Roan, Serenade,
Safari, GC 84051-31-1, GC 2043, G 1882, SREB-
15C,G7959,G8527,G2843,GC487021-26-3-1B,
PI 417132, BSPS 48A-3B, NGDT 4.11-5 most of
which had less than 5 nodules per plant each
(data not shown).
There were more soybean genotypes that
responded to Bradyrhizobium japonicum strain
USDA 110 (soybean-type inoculant) than to
Bradyrhizobium sp. strain USDA3456 (Table 4).
These included the genotypes that had over 10
nodules per plant. In terms of effective nodules,
46 genotypes had over 50% effective nodules.
On the other hand, 25 genotypes (about 38.5%
of the assessed germplasm) had each over 10
nodules, of which at least 50% effective and over
TABLE2.Summaryofresultsfromlinearmixedmodelanalysis
VariablesNumberofnodules(NN)Percentageofeffectivenodules(NE)Totalfreshweightofnodules(NFW)Totaldryweightofnodules(NDW)
Termsd.f.Fstatisticd.f.Fstatisticd.f.Fstatisticd.f.Fstatistic
Rh_levl2104.31***27722.53***29.32***2457.59***
Genotypes644.88***647.25***642.88***642.50***
Rh_levl.Genotypes1283.45***12827.80***1283.02***1282.87***
***=Veryhighlysignificant;Rh-level=Rhizobiumlevel
6. E.E.AGOYIetal.54
TABLE 3. Measured traits for the 12 genotypes responsive to Bradyrhizobium sp. strain USDA3456
Genotypes Origin Bradyrhizobium sp. strain USDA 3456 (control)
Number of nodules per plant Effective nodules (%) Total fresh weight of nodules (mg) Total dry weight of nodules (mg)
WonderSoya IITA 40(8) 85.84(25.26) 414.70(60.00) 149.78(21.44)
NamSoy 4M Uganda 36(14) 81.20(14.65) 345.60(62.70) 119.11(35.33)
K-Local - 19(10) 85.27(14.52) 317.30(41.80) 113.11(26.67)
MakSoy 3N Uganda 33(6) 56.60(8.15) 352.40(86.10) 111.67(9.50)
NamSoy 3 Uganda 22(4) 80.36(2.56) 294.70(40.10) 96.33(4.89)
NamII IITA 42(4) 82.65(0.00) 168.60(11.90) 92.78(0.33)
Bulindi 48C Uganda 38(14) 64.90(19.92) 153.90(79.80) 71.94(30.89)
Kabanyolo 1 Uganda 19(3) 73.27(4.76) 139.20(44.80) 67.11(4.11)
UG 5 - 17(8) 57.87(2.38) 189.30(28.70) 61.67(9.00)
MakSoy 5N Uganda 11(18) 74.58(25.44) 155.90(60.00) 60.78(30.67)
MakSoy 2N Uganda 12(3) 82.53(3.51) 113.20(34.4) 59.89(4.00)
Soprano Zimbabwe 13(2) 65.79(4.17) 136.80(43.10) 54.83(1.00)
Mean 12.79(5.36) 31.35(6.07) 97.6(32.1) 36.8(10.46)
SE 0.86(0.85) 1.760(1.738) 8.75(8.67) 2.36(2.34)
CV (%) 97.46 73.13 111.32 102.66
LSD 2.387 4.87 24.20 6.53
Mean values for control are indicated in brackets
7. Screening soybean genotypes for promiscuous symbiotic association 55
TABLE 4. Measured traits for the top 25 genotypes under Bradyrhizobium japonicum strain USDA110
Genotypes Origin Bradyrhizobium japonicum strain USDA 110 (control)
Number of Effective Total fresh Total dry
nodules nodules (%) weight of weight of
per plant nodules (mg) nodules (mg)
NIIXGC 20.3 Uganda 81(11) 94.71(9.38) 930.00(93.10) 228.78(33.11)
G-85037-2-3-54 Uganda 45(6) 87.51(0) 630.80(44.70) 128.00(16.06)
NIIXGC 17.3 Uganda 40(24) 69.57(14.24) 552.00(131.6) 122.67(73.67)
G 2843 AVRDC 30(1) 93.19(4.17) 479.90(13.6) 110.11(0.44)
G10427 AVRDC 16(3) 86.65(10.26) 406.40(27.7) 102.56(3.44)
GC 2043 AVRDC 24(1) 89.74(0) 429.30(11.2) 100.00(0.22)
GC487021-26-3-1A AVRDC 22(1) 76.19(0) 367.00(11.7) 96.00(0.22)
UG 5 - 52(8) 65.39(2.38) 329.60(28.7) 92.33(9)
PI567056 USA 39(4) 90.95(0) 323.00(10.7) 91.11(1.44)
NamSoy 3 Uganda 24(4) 93.41(2.56) 293.30(40.1) 89.74(4.89)
NIIXGC 44.2 Uganda 39(5) 85.49(3.03) 355.40(34.9) 88.89(5.33)
G 57 AVRDC 27(1) 91.13(0) 377.70(9.7) 77.56(0.89)
G 1882 AVRDC 20(1) 89.23(0) 292.00(0.3) 73.89(0.11)
NIIXGC 7.2 Uganda 31(12) 59.74(10.2) 284.90(30.3) 73.78(1.67)
Kabanyolo 1 Uganda 16(3) 70.52(4.76) 312.90(44.8) 72.22(4.11)
Santa Zimbabwe 19(2) 53.19(0) 250.40(16) 66.89(1.67)
NamSoy 4M Uganda 33(14) 89.75(14.65) 277.20(62.7) 65.67(35.33)
NIIXGC 43.1 Uganda 44(20) 78.57(36.75) 262.20(112.3) 64.67(42.33)
G 50 AVRDC 10(1) 71.66(0) 202.10(10.6) 63.89(0.44)
Soprano Zimbabwe 19(2) 81.4(4.17) 236.00(43.1) 60.78(1)
BSPS 48A-31 Uganda 34(7) 60.15(10.74) 301.70(29.6) 53.67(6.56)
Duiker Zimbabwe 13(6) 270.1(0) 270.10(48.7) 52.00(3.78)
GC00138-29 AVRDC 17(3) 74.73(21.05) 346.10(38.2) 51.33(11.78)
SS8645-23-2 AVRDC 16(1) 77.36(0) 268.70(0.2) 51.00(0.11)
WonderSoya IITA 17(8) 87.67(25.26) 231.00(60) 50.78(21.44)
Mean 19(5) 62.36(6.07) 197.9(32.1) 48.47(10.46)
SE 0.857(0.85) 1.760(1.738) 8.7(8.67) 2.35(2.34)
CV (%) 97.46 73.13 111.32 102.66
LSD 2.387 4.87 24.20 6.53
*Six (in bold) of the twelve genotypes highly responsive to Bradyrhizobium sp. Strain USDA 3456 have good performance with
B. japonicum USDA110 as well. *Mean values for control are in brackets
50 mg as dry weight of nodules (NDW), with
equally high fresh nodule weights (Table 4).
Genotype NIIXGC 20.3 exhibited the highest
performance in all measured traits, with 81
nodules per plant, 94.71% of effective nodules,
930 mg as NFW, and 228.78 mg as NDW.
In contrast with the situation observed with
Bradyrhizobium sp. strain USDA 3456 (cowpea-
type), whereby tropical origin germplasm were
more responsive, most of the genotypes
responsive to Bradyrhizobium japonicum strain
USDA 110 were from AVRDC (10 genotypes);
followed by breeding lines from MUARIK (8
genotypes) (Table 4). There were only 6
genotypes responsive to both Bradyrhizobium
sp. strain USDA 3456 and Bradyrhizobium
japonicum strain USDA 110;and these were UG5,
Soprano, Wondersoya, NamSoy 4M, NamSoy 3
and Kabanyolo 1.
As for the overall predictions provided by
the Linear Mixed Model (LMM) analysis, the
soybean cultivars screened were more responsive
8. E.E. AGOYI et al.56
to Bradyrhizobium japonicum strain USDA 110
than to Bradyrhizobium sp. strain USDA 3456.
Under Bradyrhizobium japonicum strain USDA
110 (soybean-type inoculant), genotypes yielded
about 19 nodules per plant, of which 62.35% were
effective, the NFW and NDW being 198.1 mg
and 48.52 mg, respectively. As noted above,
nodule number was lower (13 nodules of which
31.27% were effective) under Bradyrhizobium
sp. strain USDA 3456 (cowpea-type inoculant)
with 97.5 and 36.7 mg as NFW and NDW,
respectively. The least responsive genotypes
included MakSoy 1N, MakSoy 4N, NamSoy I,
Gazelle, Siesta, G 7959, G 8527, GC 487021-26-3-
1B, BSPS 48A-9, and NGDT 4.11-5 (Data not
shown). They had less than 5 nodules per plant
each.
The analysis indicated highly significant
positive correlations (P=0.00) between the
different variables. Under the cowpea-type
inoculant, as well as under soybean-type
inoculant, the highest correlation (r = 0.956) was
shown between fresh and dry weight of nodules
(NFW*NDW), followed by nodule number and
dry weight (r =0.789) (NN*NDW), Although
number of nodules and percentage of effective
nodules (NN*NE) were positively correlated,
they showed the lowest (r ranges from 0.555 to
0.616) correlation coefficient for each treatment
(Table 5). About 38.5% of the screened genotypes
responded to USDA 110 compared to 18,46%.
DISCUSSION
There were nodules observed under the sterilised
soils (control), indicating that sterilisation was
incompletely done. However, it did not affect the
study significantly because more nodules were
observed following inoculation, under both
strains USDA 3456 and USDA 110.
Our results showed that very few accessions
(12), all of tropical origin, were responsive to
Bradyrhizobium sp. strain USDA 3456 (cowpea-
type inoculant). This is consistent with the
observation made by IITA when screening
geographically diverse soybean accessions for
compatibility with indigenous rhizobia (Terefa,
2011). Among the 400 genotypes screened, 10
predominantly local genotypes, were found to
form effective symbiotic association with the
native rhizobia at five locations in Nigeria (Terefa,
2011). Relatedly, Arulnandhy (1987) found an
American high yielding recommended genotype
(Pb-1) to be less responsive to native strains in
African study sites.
In our study, the number of nodules under
Bradyrhizobium sp. strain USDA 3456 ranged
from 0 to 42 nodules per plant and significantly
changed with plant genotypes. Plants with
nodules ranging from 11 to 42 for the 12
genotypes were considered as promiscuous
(Pulver et al., 1985). Similar results were reported
by Arulnandhy (1987), whereby the number of
TABLE 5. Correlation test between pairs of traits measured
Pairs of traits Control Bradyrhizobium sp. (strain USDA 3456) Bradyrhizobium japonicum(strainUSDA110)
Coefficient Coefficient Coefficient
NN*NE 0.555*** 0.616*** 0.561***
NN*NFW 0.780*** 0.675*** 0.823***
NN*NDW 0.901*** 0.789*** 0.830***
NE*NFW 0.684*** 0.697*** 0.632***
NE*NDW 0.618*** 0.785*** 0.597***
NFW*NDW 0.826*** 0.956*** 0.975***
NN = Number of Nodules, EF = Effective Nodules, NFW = Fresh Weight of Nodules, NDW = Dry Weight of Nodules. *** =
Very highly significant
9. Screening soybean genotypes for promiscuous symbiotic association 57
nodules ranged from 1 to 37 per plants; while
screening different promiscuous and non-
promiscuous soybean genotypes for response
to native Bradyrhizobium strains. Similarly,
Muhammad (2010) observed 15 to 36 nodules per
plants for the IITA promiscuous cultivar (TGX
1485).
As for dry weight of nodules (NDW), Gwata
et al. (2004), reported 62 mg for the cultivar
SamSoy known as highly promiscuous, which
falls into the range (54.83 to 149.78 mg per plant)
observed in the 12 promiscuous genotypes
selected in our study. This indicates that
promiscuous soybean genotypes produce
enough nodule numbers and sizes to function as
powerhouses for nitrogen fixation. Moreover,
over 50% of these nodules were effectives.
Although there were more genotypes
responsive to B. japonicum (Table 4), more than
60% of the genotypes screened were not
responsive to BNF, this could be the result of
incompatible Bradyrhizobium strain in the
inoculant, thus emphasizing that breeding efforts
should be oriented in sourcing genotypes with
high nodulation ability, coupled with promiscuity
in order to develop cultivars that are suitable for
production in the African soybean production
context.
The maximum number of nodules observed
(81 nodules per plant) in genotype NIIXGC 20.3
was higher than 53 nodules previously reported
by Kumaga and Ofori (2004), while testing B.
japonicum on two other soybean cultivars.
Mandimbaetal.(1994)earlierreportedamaximum
of 51 nodules per plant when testing different
strains of B. japonicum on soybean cultivar FN3.
The fact that our study showed a higher nodule
number under soybean-type inoculant may be
explained by the use of sterilised soil that would
have lowered competition among strains and,
hence enhanced the symbiotic association. The
fact that the pair “nodule number-effective
nodules”, even though positively correlated,
showed the lowest correlation coefficient (r =
0.555) for all the treatments, suggesting that the
number of nodules should not be considered
alone; it must be supported by a reasonable
percentage of effective nodules before a
genotype can be taken as being responsive to
Bradyrhizobia. A minimum of 50% of effective
nodules coupled, with a high number of nodules,
at least 10 per plant (Corbin et al., 1977) should
be required to adjudicate a genotype as
responsive to Bradyrhizobia.
A high positive correlation (r = 0.79) was
observed between nodule number (NN) and dry
weight (NDW). This is in agreement with the
earlier findings of Arulnandhy (1987), who
reported a significantly high correlation (r = 0.72)
between nodule number and nodule dry weight.
The high level of significance (p<0.001) of
interaction between genotypes and inoculation
levels for most measured traits, is a clear indication
that the genotypes responded differently to
BradyrhizobiastrainsUSDA3456andUSDA110,
which were used in this study as a measure of
promiscuity. In addition to that, more soybean
genotypes responded to USDA 110 than USDA
3456. These suggest a complex relationship which
may be due to genetic effect in rhizobia-soybean
symbiosis.
CONCLUSION
The study constitutes a preliminary work that
provides helpful decision tool for use in the
choice of potential parents for soybean breeding
programme. It is clear that breeding solutions for
promiscuous nodulation lie within African
soybean germplam. The results of this study can
be used to choose genotypes for direct selection
for promiscuous nodulation, followed by
replicated trials or parental lines to be used in a
breeding scheme focusing on promiscuous
nodulation trait. Soybean genotypes NamII,
WonderSoya, Bulindi 48C, NamSoy 4M, MakSoy
3N, NamSoy 3, K-Local, Kabanyolo 1, UG 5,
Soprano, MakSoy 2N, MakSoy 5N are good
candidate parental lines for initiating a soybean
programme focusing on promiscuous nodulation.
We recommend that investigations be made
to avail easier and more accurate methods to
assess the effectiveness of nodules and infer on
the ability of genotypes to fix nitrogen.
ACKNOWLEDGEMENT
We acknowledge the Intra-ACP SHARE for
financial and moral support, and BrunoAwio for
the discussions during data analysis.
10. E.E. AGOYI et al.58
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