Growth, gas exchanges and accumulation of inorganic matter of Populus nigra L...Innspub Net
Tunisia has made considerable efforts to solve major environmental problems. Reforestation of vast marginal
spaces with appropriate species, such as poplar, is one of the economic and environmental challenges (I-488). The fast-growingof this rupicolous species has a high specific versatility in its use. However, its need for water will limit their use in reforestation in areas where water resources are scarce. To cope with this situation, the use of unconventional water resources, including wastewater treatment, is a promising way to increase domestic
production of wood. Thus, the treated wastewater is valued as a source of unquestionable water, but also as a
source of nutrients. These plants were raised under non-binding for four months and divided into two lots
irrigated daily to field capacity with (i) potable water (control : T) and (ii) with treated waste water (TWW).
Biomass production, gas exchange and some mineral ions were measured during the experiment, in summer. Our results indicate that irrigation with treated wastewater has submitted a substantially marked effect resulting in an increase of gas exchange. Furthermore, after 60 days, the accumulation of certain metal ions (Cd, Pb and Ni) has resulted in a major malfunction on gas exchange.
Antioxidant activity, photosynthetic rate, and Spectral mass in bean Plants (...IJEABJ
An increase in antioxidant activity is a common response in plants as a defense mechanism against biotic and abiotic stress factors, such response is also generated with the exogenous application of "defense activators", which have negative effects on plant metabolism. In this work, bean plants (Phaseolus vulgaris L.) cv. Pinto Nacional were treated with jasmonic acid (0.5 mM), salicylic acid (2 mM), Trichoderma asperellum (105 spores/ml), and Bacillus pumilus (105 CFU / mL), in order to determine the level of structural and metabolic response of the plants. On the seventh day after the application of the treatments, it was measured the enzymatic activity of catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD). In addition, leaf impressions were taken to measure the stomatal opening and conductance, photosynthetic rate, and the mass spectrum (mass/charge, m/z). The antioxidant activity increased in plants treated with jasmonic acid and T. asperellum, which in turn significantly increased the stomatal opening and conductance, and photosynthetic rate. The mass profile showed that the plants treated with T. asperellum have a greater quantity of masses/charge, of which some had statistically highly significant difference according to the means test Tukey (p <0.05). It is concluded that some defense activators such as jasmonic acid and T. asperellum increase the antioxidant activity, defense response that concurs with the high photosynthetic and metabolic rate in bean plants.
Growth, gas exchanges and accumulation of inorganic matter of Populus nigra L...Innspub Net
Tunisia has made considerable efforts to solve major environmental problems. Reforestation of vast marginal
spaces with appropriate species, such as poplar, is one of the economic and environmental challenges (I-488). The fast-growingof this rupicolous species has a high specific versatility in its use. However, its need for water will limit their use in reforestation in areas where water resources are scarce. To cope with this situation, the use of unconventional water resources, including wastewater treatment, is a promising way to increase domestic
production of wood. Thus, the treated wastewater is valued as a source of unquestionable water, but also as a
source of nutrients. These plants were raised under non-binding for four months and divided into two lots
irrigated daily to field capacity with (i) potable water (control : T) and (ii) with treated waste water (TWW).
Biomass production, gas exchange and some mineral ions were measured during the experiment, in summer. Our results indicate that irrigation with treated wastewater has submitted a substantially marked effect resulting in an increase of gas exchange. Furthermore, after 60 days, the accumulation of certain metal ions (Cd, Pb and Ni) has resulted in a major malfunction on gas exchange.
Antioxidant activity, photosynthetic rate, and Spectral mass in bean Plants (...IJEABJ
An increase in antioxidant activity is a common response in plants as a defense mechanism against biotic and abiotic stress factors, such response is also generated with the exogenous application of "defense activators", which have negative effects on plant metabolism. In this work, bean plants (Phaseolus vulgaris L.) cv. Pinto Nacional were treated with jasmonic acid (0.5 mM), salicylic acid (2 mM), Trichoderma asperellum (105 spores/ml), and Bacillus pumilus (105 CFU / mL), in order to determine the level of structural and metabolic response of the plants. On the seventh day after the application of the treatments, it was measured the enzymatic activity of catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD). In addition, leaf impressions were taken to measure the stomatal opening and conductance, photosynthetic rate, and the mass spectrum (mass/charge, m/z). The antioxidant activity increased in plants treated with jasmonic acid and T. asperellum, which in turn significantly increased the stomatal opening and conductance, and photosynthetic rate. The mass profile showed that the plants treated with T. asperellum have a greater quantity of masses/charge, of which some had statistically highly significant difference according to the means test Tukey (p <0.05). It is concluded that some defense activators such as jasmonic acid and T. asperellum increase the antioxidant activity, defense response that concurs with the high photosynthetic and metabolic rate in bean plants.
Master's research proposal presentation to the department of Horticulture and Crop Science at The Ohio State University.
Abstract: Chile peppers (Capsicum annuum), which grow in southern Mexico on a environmental gradient from warm and humid coastal areas to the cool, dry highlands, present a unique opportunity to study the range of environmental tolerance and adaptation. Understanding how chile peppers have adapted to local conditions will provide insight into the importance of specific environmental factors in organizing diversity across the landscape, and highlight traits with potential for future crop improvement. Over recent years, our international research team has sampled more than 200 plants from wild, semi-wild and domesticated populations across southern Mexico. Seed from these original collections will undergo one generation of increase in the greenhouse to eliminate maternal environmental effects in seeds used for planned phenotyping experiments. Genome-wide genotyping (GBS) will be conducted on these parent plants. I will conduct two experiments aimed at assessing short-term and long-term resistance to abiotic stress. I will study short-term resistance to drought and heat stress in seedlings by overlaying factorial environmental treatments (simulating the interaction between cool highland/warm lowland temperatures and moist coastal/drier inland environments of Oaxaca, Mexico) onto chile pepper accessions from our collection. I will assess long-term (i.e. full life cycle) drought resistance by comparing the effect of a field capacity treatment with an empirically determined water stress treatment across accessions in factorial combination. Habitat drought stress indices based on the Thornthwaite potential evapotranspiration (PET) model and the Hamon estimator will be assessed as drought resistance predictors. Using a genome wide association study (GWAS) approach, I will identify significant associations between genetic markers and observed values of gas exchange, as well as plant morphology, growth characteristics and overall fitness. Information gathered through this study will provide evidence for the genetic basis of both adaptive variation and phenotypic plasticity, therefore furthering the understanding of genetic diversity in chile peppers.
Learn how spaceflight can be harnessed to improve crop production on Earth. Microgravity stresses plants and other associated organisms creating opportunities to improve crop performance on Earth and beyond.
Hazard assessment for a pharmaceutical mixture detected in the upper Tennesse...GJESM Publication
Widespread use of pharmaceuticals has resulted in mixture concentrations ranging from mg/L in
effluent to μg/L concentrations in surface water. In a 2008 study, 13 pharmaceuticals, ranging in amounts from 0.0028
to 0.1757 μg/l, were identified in the Tennessee River, USA and its tributaries. In order to address the need for risk
assessment of environmentally relevant pharmaceutical mixtures, Daphnia magna 21-d life cycle tests were performed on a mixture of 11 of the 13 pharmaceuticals as well as on the individual components of the mixture. Mixture exposures were based on the same initial ratios of individual compounds, up to 1000x the initial mixture concentrations. The endpoints of mortality, time to first brood, size, and fecundity were assessed. The LOEC of the 11- pharmaceutical mixture was determined to be 100x greater than the measured mixture concentration detected in the Tennessee River, with the NOEC being 75x that of the measured mixture. Single concentrations of pharmaceuticals within the mixture up to the 100x LOEC were not statistically different from control for any of the assessed endpoints. Thus, no single pharmaceutical was deemed predominately responsible for the mixture toxicity at the concentrations tested. While mixtures of pharmaceuticals are common in many systems, based on the findings of the present study, they may not pose a significant acute or chronic hazard to aquatic invertebrates at current concentrations.
Biomass partitioning, leaf area index, and canopy greenness: the Good, the BA...remkoduursma
Seminar presented to the Hawkesbury Institute for the Environment's weekly seminar series on 28 October 2015. Topics include a global database of plant biomass and allometry, leaf area index at the EucFACE, and canopy greenness as measured with phenocams.
Trees Lose Their Leaves Later in Agroforestry SystemsIJEAB
In Brazilianagroforestry systems (AFS), Cordia oncocalyx trees, a native species of Caatinga, lose their leaves late in relation to the trees of the same species occurring in secondary forest. Our hypothesis is that, due to environmental features, the trees of the AFS maintain better water status. This work aims to present environmental humidity (rainfall, soil moisture and air relative humidity) and trees (photosynthesis, stomatal conductance and transpiration) data to explain the late loss of leaves in anagrosilvopastoral system (AGP) in the Brazilian semiarid region compared to a secondary forest (SF).Meteorological data were obtained from two weather stations installed in the AGP and SF areas. The physiological traits were measured using an infrared gas analyzer. There was a correlation between physiological processes (transpiration and stomatal conductance) and soil water content in plants of AGP, but not in SF, showing some independence of the plants of this system to variations in soil moisture. This indicates that AGP plants may have developed the physiological and anatomical features that enable to them to keep photosynthesis even when climatic conditions are more severe. Although the most inhospitable environmental conditions in the AGP system, the lower density of plants, and therefore less competition for water, favoring photosynthesis longer, causing the leaves to fall later.
Master's research proposal presentation to the department of Horticulture and Crop Science at The Ohio State University.
Abstract: Chile peppers (Capsicum annuum), which grow in southern Mexico on a environmental gradient from warm and humid coastal areas to the cool, dry highlands, present a unique opportunity to study the range of environmental tolerance and adaptation. Understanding how chile peppers have adapted to local conditions will provide insight into the importance of specific environmental factors in organizing diversity across the landscape, and highlight traits with potential for future crop improvement. Over recent years, our international research team has sampled more than 200 plants from wild, semi-wild and domesticated populations across southern Mexico. Seed from these original collections will undergo one generation of increase in the greenhouse to eliminate maternal environmental effects in seeds used for planned phenotyping experiments. Genome-wide genotyping (GBS) will be conducted on these parent plants. I will conduct two experiments aimed at assessing short-term and long-term resistance to abiotic stress. I will study short-term resistance to drought and heat stress in seedlings by overlaying factorial environmental treatments (simulating the interaction between cool highland/warm lowland temperatures and moist coastal/drier inland environments of Oaxaca, Mexico) onto chile pepper accessions from our collection. I will assess long-term (i.e. full life cycle) drought resistance by comparing the effect of a field capacity treatment with an empirically determined water stress treatment across accessions in factorial combination. Habitat drought stress indices based on the Thornthwaite potential evapotranspiration (PET) model and the Hamon estimator will be assessed as drought resistance predictors. Using a genome wide association study (GWAS) approach, I will identify significant associations between genetic markers and observed values of gas exchange, as well as plant morphology, growth characteristics and overall fitness. Information gathered through this study will provide evidence for the genetic basis of both adaptive variation and phenotypic plasticity, therefore furthering the understanding of genetic diversity in chile peppers.
Learn how spaceflight can be harnessed to improve crop production on Earth. Microgravity stresses plants and other associated organisms creating opportunities to improve crop performance on Earth and beyond.
Hazard assessment for a pharmaceutical mixture detected in the upper Tennesse...GJESM Publication
Widespread use of pharmaceuticals has resulted in mixture concentrations ranging from mg/L in
effluent to μg/L concentrations in surface water. In a 2008 study, 13 pharmaceuticals, ranging in amounts from 0.0028
to 0.1757 μg/l, were identified in the Tennessee River, USA and its tributaries. In order to address the need for risk
assessment of environmentally relevant pharmaceutical mixtures, Daphnia magna 21-d life cycle tests were performed on a mixture of 11 of the 13 pharmaceuticals as well as on the individual components of the mixture. Mixture exposures were based on the same initial ratios of individual compounds, up to 1000x the initial mixture concentrations. The endpoints of mortality, time to first brood, size, and fecundity were assessed. The LOEC of the 11- pharmaceutical mixture was determined to be 100x greater than the measured mixture concentration detected in the Tennessee River, with the NOEC being 75x that of the measured mixture. Single concentrations of pharmaceuticals within the mixture up to the 100x LOEC were not statistically different from control for any of the assessed endpoints. Thus, no single pharmaceutical was deemed predominately responsible for the mixture toxicity at the concentrations tested. While mixtures of pharmaceuticals are common in many systems, based on the findings of the present study, they may not pose a significant acute or chronic hazard to aquatic invertebrates at current concentrations.
Biomass partitioning, leaf area index, and canopy greenness: the Good, the BA...remkoduursma
Seminar presented to the Hawkesbury Institute for the Environment's weekly seminar series on 28 October 2015. Topics include a global database of plant biomass and allometry, leaf area index at the EucFACE, and canopy greenness as measured with phenocams.
Trees Lose Their Leaves Later in Agroforestry SystemsIJEAB
In Brazilianagroforestry systems (AFS), Cordia oncocalyx trees, a native species of Caatinga, lose their leaves late in relation to the trees of the same species occurring in secondary forest. Our hypothesis is that, due to environmental features, the trees of the AFS maintain better water status. This work aims to present environmental humidity (rainfall, soil moisture and air relative humidity) and trees (photosynthesis, stomatal conductance and transpiration) data to explain the late loss of leaves in anagrosilvopastoral system (AGP) in the Brazilian semiarid region compared to a secondary forest (SF).Meteorological data were obtained from two weather stations installed in the AGP and SF areas. The physiological traits were measured using an infrared gas analyzer. There was a correlation between physiological processes (transpiration and stomatal conductance) and soil water content in plants of AGP, but not in SF, showing some independence of the plants of this system to variations in soil moisture. This indicates that AGP plants may have developed the physiological and anatomical features that enable to them to keep photosynthesis even when climatic conditions are more severe. Although the most inhospitable environmental conditions in the AGP system, the lower density of plants, and therefore less competition for water, favoring photosynthesis longer, causing the leaves to fall later.
Ultrastructural and physiological aspects of eucalyptus clones submitted to b...Innspub Net
This work aimed evaluate ultrastructural and physiological aspects of 35-days old eucalyptus, clones 13; 59 and 131, by submitting them to the following barium doses: null, 125; 250; 500 and 1000 ppm of barium solution, with four repetitions. Due to the exposition to barium, there was appearance of phytotoxicity on the leaves. Then, it was determined the following variables: Phloem of Diameter of Leaf and Root (PDL and PDR); Xylem of Diameter of Leaf and Root (XDL and XDR) and Thickness of Palisade Parenchyma (PP); Spad Index (SPADI); Inferior Face of Stomata Functionality of the Inferior Face (IFSF) and Stomach Density of the Inferior Face (SD). Barium negatively influenced the leaf ultrastructure of eucalyptus and its physiology. Eucalyptus clones 13; 59 and 131 are susceptible to barium solution. Barium caused root and ultrastructural leaves and root damages on eucalyptus clones. Xylem diameter of leaves of eucalyptus clones 13 and 59 were not harmed as exposed to Barium.
Jatropha-based alley cropping system’s contribution to carbon sequestrationInnspub Net
The study was conducted to evaluate the total carbon stocks sequestered in a Jatropha – based alley cropping system treated with varying fertilizer applications. The study was laid out in Randomized Complete Block Design with three replications. The alley was planted with corn in two seasons Treatments include control (no fertilizer), organic fertilizer and inorganic fertilizer applied to the alley crops. Findings showed that the treatments with fertilizer applications had higher carbon stock in the jatropha hedges. The carbon content of the corn stover was also higher in organic and inorganic fertilizer-applied treatments. However, highest soil carbon content was shown in treatments applied with organic fertilizer (4.28 Ton ha-1). The inorganic fertilizer treatment had the lowest soil carbon content with a mean of 4.28 Ton ha-1. In terms of total carbon stock of the entire jatropha-based alley cropping system, there was a significant difference among treatments with organic fertilizer application having the highest mean of 7.79 Ton ha-1 while the inorganic treated plots had 6.53 Ton ha-1. The no fertilizer treatment had the least carbon stocks with 6.53 Ton ha-1. This recent study revealed that the jatropha-based alley cropping system is a potential land-use for carbon sequestration. This farming system needs to be promoted in upland areas to function not only as soil and water conservation measures but also as a possible remedy for global warming. Get the Abstract and full articles at: http://www.innspub.net/ijaar/jatropha-based-alley-cropping-systems-contribution-to-carbon-sequestration/
Seasonal growth patterns of Arundo donax L. in the United States | IJAAR @sli...Innspub Net
Giant reed (Arundo donax L.) has been extensively evaluated as a dedicated energy crop for biomass and biofuel production in southern Europe and the United States, with very favorable results. Current agronomic and biologic research on giant reed focuses on management practices, development of new cultivars, and determining differences among existing cultivars. Even though detailed information on the growth patterns of giant reed would assist in development of improved management practices, this information is not available in the United States. Therefore, the objective of this 2-year field study was to describe the seasonal growth patterns of giant reed in Alabama, United States. Changes in both plant height and biomass yield of giant reed with time were well described by a Gompertz function. The fastest growing period occurred at approximately 66 d after initiation of regrowth (mid-May), when the absolute maximum growth rate was of 0.045 m d-1 and 0.516mg ha-1 d-1. After mid-May, the rate of growth decreased until maturation at approximately 200 d after initiation of regrowth (mid- to late September). The observed maximum average plant height and biomass yield were 5.28 m and 48.56mg ha-1, respectively. Yield decreased following maturation up to 278 d after initiation (early to mid-December) of growth in spring, partly as a result of leaf loss, and was relatively stable thereafter.
Diversity of halophilic mycoflora habitat in saltpans of Tuticorin and Marakk...Open Access Research Paper
Highly diverse biological system of solar salterns with different salinities, often provide high densities of mycofloral populations, makes the salterns excellent model systems for both its diverse and activity. In this study, diversity of halophilic fungi in six stations which includes reservoir, evaporator and crystallizer pond of both Marakkanam and Tuticorin saltpans in relation to environmental parameters were carried out for a period of two years. 95 species of halophilic fungi from water and sediment samples belongs to 41 genera were recorded in both saltpans. Aspergillus and Penicillium species were recorded as dominant, vast differences in growth of each isolate at different salt concentrations in the ponds were observed. This paper also elucidated the slight fluctuations in physico-chemical parameter among the ponds with respect to seasonal variations were also recorded.
Effect of some abiotic factors on the concentration of β- sitosterol of Prunu...Innspub Net
Prunus africana is a medicinal plant which develops in the mountains of several African countries. β-sitosterol can be used as a marker for the control of the product quality of the aforementioned plant in terms of phytotherapy. Farmers and public authorities do not have information on the influence of altitude and chemical characteristics of soils on the concentration of β- sitosterol of P. africana. To contribute to solve the problem, this research, carried out in Cameroon, aims to appreciate the effect of abiotic factors on the above phenotypic character. In nine composite samples of barks taken at different altitudes, the
concentration of β-sitosterol is appreciated via qualitative analyses by Thin Layer Chromatography, High Performance Liquid Chromatography and quantitative analyses by Gas Chromatography coupled with the Mass Spectrometry. The chemical analyses of soils taken under the stems of the aforementioned trees were made. The statistics were carried out using the SAS software. The concentration of β-sitosterol in each population of P. africana varies from zero to 38.65 μg/ml. There is
variability between the averages of the aforementioned concentration with respect to altitude and chemical elements of the soils but the differences are not significant. The Ascending Hierarchical Clustering distributes populations into three groups. These
tools obtained are indispensable for the ground management, the products exploited from this tree species and the production of seeds for creating forest and agro-forest plantations.
Impact of Compost Prepared from Invasive Alien Species in Alleviating Water S...YogeshIJTSRD
Invasive alien plant species are major thread to biodiversity, climate change and environmental sustainability. Management of these invasive alien plant species become a typical task at global level. Composting can be an efficient and environment friendly solution for management of these invasive alien species. The aim of present study was to evaluate the effect of compost prepared from three invasive alien species Cuscutareflexa, Eupatorium adenophorum and Lantana camaraon the tomato plant vigour, antioxidant and nutrient content under water deficit and irrigated well watered conditions. The results revealed that Cuscutareflexa CR compost treatment gave highest shoot length 23.0 , 23.7 , root length 30.0 , 21.4 , shoot fresh weight 47.9 , 52.2 , shoot dry weight 71.0 , 49.4 and root dry weight 66.7 , 51.5 , under water stressand irrigated conditions, respectively. The application of compostCR under water stress has enhanced chlorophyll and prolinecontent over control. Similarly, antioxidant enzymes analysis showed the increased superoxide dismutase 1.33 2.17fold , peroxidase 1.38 1.82fold and catalase 1.06 1.73fold activity under water deficit condition. Nutrient content such as nitrogen, phosphorus, potassium and sodiumin tomato leaf were higher under both water stress and irrigated conditions compared to their respective control. It can be concluded from above outcomes that compost prepared from invasive alien species have potential to ameliorate the negative effects of water stress and enhance the tomato growth. Sandhya Bind | A. K. Sharma "Impact of Compost Prepared from Invasive Alien Species in Alleviating Water Stress in Tomato (Solanum Lycopersicum L.)" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-3 , April 2021, URL: https://www.ijtsrd.com/papers/ijtsrd39961.pdf Paper URL: https://www.ijtsrd.com/biological-science/botany/39961/impact-of-compost-prepared-from-invasive-alien-species-in-alleviating-water-stress-in-tomato-solanum-lycopersicum-l/sandhya-bind
1. #analyticsx
Presenter: Reuben Hilliard
Faculty Advisors: Dr. Paula Jackson & Dr. Brad Barney
Kennesaw State University
INTRODUCTION
Surviving Climate Change
Comparing drought & fungicide response in two riparian tree species for use in ecological restoration
Riparian zones fulfill many ecosystem functions and occur at
all elevations near rivers, streams, and in floodplains. They
function as a natural buffer against erosion in river and
stream banks, filter downstream pollution, and provide
increased habitat complexity (Wildlife, 2006). Due to
development, logging, and expanding agriculture, many
riparian zones have been destroyed or depleted. This has a
profound ecological effect that leads to increased
sedimentation and pollution in natural water systems
(Hernandez-Santana, 2011). These zones often undergo
rehabilitation to restore health back into the surrounding
environment. Salix nigra (Black Willow) and Platanus
occidentalis (American Sycamore) are two common riparian
species of trees (Conger, 1996). Of these, Salix nigra is
frequently used to restore these areas, however not much
information exists on the ability to use Platanus occidentalis
for this purpose. This research is part of a larger study
looking at the ecology and physiology of both of these
species, with the overarching aim of comparing the behavior
of Platanus occidentalis to the more widely studied Salix
nigra, and determining the feasibility of using Platanus
occidentalis in restoration processes. Of additional
importance is the fungal biota which inhabit the soil
beneath these trees. Mycorrhizal fungi have been reported
to improve plant growth in many crops through enhanced
root growth and function (Westphat et al, 2008). It also
improves early plant establishment and increased the most
valuable early fruit yield under some environmental stress
conditions. This is of ecological importance and will be
incorporated in this study.
Salix nigra
leaves (left)
and
Salix nigra
tree (right)
Platanus
occidentalis
leaves (left)
and
Platanus
occidentalis
tree (right)
(Image:
bioimages.vanderbilt.edu/baskauf
/15370.htm)
(Image:
bioimages.vanderbilt.edu/baska
uf/23004.htm)
(Image:
bioimages.vanderbilt.edu/baska
uf/29666.htm)
(Image:
http://bioimages.vanderbilt.ed
u/baskauf/13574.htm)
STATISTICAL MODELS
Randomized Complete Block Design
yij = µ + αi + bj + εij
Mixed Effects Model
y = Xβ + Zu + ε
Unstructured Covariance Matrix
Autoregressive Heterogeneous Covariance Matrix
One-way ANOVA
yij = µ + τi + εij
Sum of Mean
Squares df Square F
Treatment SSR / dfF = MSR MSR/MSE
Error SSE / dfE = MSE
Total SST dfT
Both species can be found in overlapping geographical
regions of the Southeast.
2. #analyticsx
Presenter: Reuben Hilliard
Faculty Advisors: Dr. Paula Jackson & Dr. Brad Barney
Kennesaw State University
Surviving Climate Change
Comparing drought & fungicide response in two riparian tree species for use in ecological restoration
One cause for data errors in greenhouse experiments can be due to microclimate differences, such as light, airflow and
heat among saplings, within different planters. As stated by Brien et al. (2003), sound statistical design and analysis is
better than rearranging the position of plants during the experiment itself. In our experiment, Platanus occidentalis and
Salix nigra saplings were planted using a Randomized Complete Block Design, as seen in Table I. It involved a complete
experimental treatment within each planter series, allowing for homogenous growing conditions within a single tray,
regardless of differences among planters themselves. To account for variability in sapling size, each tray had a similar
distribution of size classes. All the saplings were tagged with unique identifiers, such as PO-01 or SN-02. 15-17
individuals of each species were subjected to a control, inundation, or drought condition; and drought with and
without the addition of mycorrhizal spores, a fungal biota, which was controlled with the addition of a fungicide,
Benomyl. In total, 31 Platanus and 34 Salix cuttings received sufficient nutrients in the form of a slow-release fertilizer
and after taking baseline measurements, were allowed to grow in planters through the spring of 2015. From May 18th
until August 23rd, a team of myself and 3 undergraduate research assistants, took anatomical and physiological
measurements.
Block 1 Block 2
A B B A
D C C D
Treatments
A: Control; No Fungi (Benomyl added) & Wet
B: Fungi & Drought
C: Fungi & Wet
D: No Fungi (Benomyl added) & Drought
Saplings planted; fertilized
Saplings measured; tagged
METHODS
For the anatomical measures, an indicator of growth rate, both the circumference and the height were taken for each
plant on a weekly basis. For the physiological data, a LICOR LI-6400 Infrared Gas Analyzer (IRGA) was used to measure
photosynthetic rate from leaves repeatedly over the period of weeks, systematically moving through the plants,
selecting a predefined leaf from a randomly selected plant from each treatment and block. This was a tedious process,
with each leaf taking up to 16min for a full measurement run. The results were used to build light response curves. Net
Photosynthetic rate, or CO2 assimilation (µmol CO2 m-2 leaf area s-1) from several trials were plotted against light
intensity, or Absorbed Photosynthetically Active Radiation (αPAR, µmol photons m-2 leaf area s-1). The slope of the
linear phase of the response curve is a measure of "photosynthetic efficiency" of the plant, or how efficiently solar
energy is converted into chemical energy. Different plants show differences in the shape of their light response curves,
which reveals characteristics of the underlying photosynthesis processes, including the efficiency at which light is
utilized by photosynthesis and the rate of O2 uptake.
In this longitudinal study, both the anatomical and the physiological data were analyzed using SAS 9.4 with the MIXED
Procedure, which models mixed effects over time.
Because a drought stress condition increases root to shoot ratio (Xu et al, 2015), to test this, 16 trees were randomly
selected from each of the treatment and species groups. After drying in the oven overnight, the dry weight of each
tree was used to calculate the root to shoot ratio. The cumulative total leaf area was taken using the LI-COR 3100C. To
detect the presence of arbuscular mycorrhizal root colonization, 160 root samples were collected from eight trees of
each species. Roots were stained using a 0.05% Trypan Blue solution and the presence of mycorrhizal structures was
quantified using the root piece method.
The LI-COR LI-6400 (left) is a portable
Photosynthesis System and a major tool for
ecological researchers in the field (LI-COR, 2013).
The function of the LI-6400 is based on detecting
differences in CO2 concentration of air before
(reference) and after (sample) it comes in contact
with the plant leaf. Differences in CO2
concentrations are detected through the use of
infrared gas analyzers. The LI-COR allows for in situ
measurements of photosynthetic rates and for
independent control of the leaf chamber CO2, H2O,
temperature, and light . Results from the LI-COR
may be downloaded into an Excel spreadsheet for
further analysis.
Physiological measurements (top left); Planters in grid – trial start date (top mid);
Anatomical measurements (top right); LI-COR 3100C Leaf Area Meter (bottom left);
Staining of greenhouse samples in 0.05% Trypan Blue solution (bottom mid); Colonized
root after staining (bottom right)
3. #analyticsx
Presenter: Reuben Hilliard
Faculty Advisors: Dr. Paula Jackson & Dr. Brad Barney
Kennesaw State University
Surviving Climate Change
Comparing drought & fungicide response in two riparian tree species for use in ecological restoration
RESULTS
Graphs, Boxplots and Bar Chart output
designed in SAS 9.4 and Tableau 9.2
Anatomical Results from the Mixed Effects Model.
Drought treatment highly significant (** p < 0.0001)
4. #analyticsx
Presenter: Reuben Hilliard
Faculty Advisors: Dr. Paula Jackson & Dr. Brad Barney
Kennesaw State University
CONCLUSIONS
Surviving Climate Change
Comparing drought & fungicide response in two riparian tree species for use in ecological restoration
The anatomical results indicate that Salix nigra and Platanus occidentalis do respond differently to drought
conditions. In fact, the interaction of the days count and the drought condition was highly significant (p < .0001).
This meant that as the experiment proceeded the drought condition became more pronounced. As seen in the
anatomical results, for the drought condition, Platanus was able to outperform Salix in the linear rate of growth
(corrected for errors), 0.86cm/Day and 0.74cm/Day, respectively. The fungicide treatment did not have a significant
effect in either species.
The physiological results indicated that the PAR level, or light intensity given to the leaf, was significant (p < 0.05). This
analysis had to be stratified by species, as none of the other factors were significant initially. When this was done,
Platanus was right on the cusp of being significant in the drought condition during period 2 (last 5 weeks of the
experiment). Even though Salix didn’t respond to the drought or fungicide treatments, this information is still of
biological interest to researchers, as it indicates that Salix can be stressed and still perform unhindered, with minimal
interruptions.
Of particular note is how well Platanus performed in the ‘No Fungicide/Drought’ (Treatment B), which can be observed
in both the light curve and the mean maxima photosynthetic output figures. But when an ANOVA was performed to
confirm the results, there was no significant difference at PAR 800 by Species and Treatment.
The ANOVAs from the Root to Shoot Ratio and Leaf Area showed no significant differences in means between Species
and Drought treatment, but of interest was the much larger variability among Salix plants. Larger Root to Shoot Ratios
among younger trees and greater variability in measurements, indicate that compared to Platanus, when Salix
scavenged for water, it struggled far more in the drought treatment.
Because Platanus performed as well or slightly better than Salix in this study, the overall results were quite positive
and allow future research to focus specifically on Platanus as a species to use in restoration of Southeastern US
riparian ecosystems.
RELEVANT SAS CODE
REFERENCES
*i) Coding the explanatory variables;
DATA research.anatomical_data;
SET together;
daysc = date - mdy(5,18,2015); dayscat = daysc;
tag = species; species = substr(tag,1,2);
fungicide = scan(treatment,1,"/");
drought = substr(scan(treatment,2,"/"),1,1);
tmt=1; if species="PO" then tmt=tmt+4;
if drought="D" then tmt=tmt+2;
if fungicide="Fungicide" then tmt=tmt+1;
RUN;
*ii) Optimal Anatomical model. Unstructured Covariance
Matrix;
PROC MIXED data = research.anatomical_data;
CLASS species drought fungicide tag blocknum dayscat;
MODEL height = species drought species|daysc
drought|daysc
/solution ddfm = kr;
REPEATED dayscat/ subject = tag(blocknum) type = un R
RCORR ; RUN;
*iii) Optimal Physiological model, stratified by species.
Autoregressive Heterogeneous Covariance Matrix;
PROC SORT data = research.master_photo; BY Species Tag
PAR; run;
PROC MIXED data = research.master_photo;
BY Species;
CLASS tag treatment blocknum PAR;
MODEL photo = treatment PAR ;
RANDOM blocknum;
REPEATED PAR /subject = tag type = arh(1) ;
LSMEANS treatment /pdiff tdiff ; RUN;
*iv) Data output for Mean Maxima Photosynthetic Rate
and Standard Errors;
ODS GRAPHICS ON;
PROC MIXED data = research.master_photo;
WHERE PAR = 800;
CLASS Tag blocknum fungicide drought species PAR
period;
MODEL photo = species*fungicide*drought
/ noint solution ddfm=kr;
RANDOM blocknum;
RANDOM int / subject=tag;
RUN;
ODS GRAPHICS OFF;
*iv) One-way ANOVA for Root to Shoot Ratio and Total
Leaf Area;
TITLE "Root to Shoot Ratio";
PROC ANOVA data=mass_area;
CLASS Fungi Drought Species ID Block drought_sps ;
MODEL Root_Shoot_Ratio = drought_sps Block;
MEANS drought_sps/Tukey;
RUN;
TITLE "Total Leaf Area";
PROC ANOVA data=mass_area;
CLASS Fungi Drought Species ID Block drought_sps ;
MODEL Leaf_Area = drought_sps Block;
MEANS drought_sps /Tukey;
RUN;
Oregon Department of Fish and Wildlife. 2006. Oregon Conservation Strategy. Oregon Department of Fish and Wildlife,
Salem, Oregon.
Hernandez-Santana, V., Asbjornsen, H., Sauer, T., Isenhart, T., Schilling, K., & Schultz, R. 2011. Enhanced transpiration
by riparian buffer trees in response to advection in a humid temperate agricultural landscape. Forest Ecology and
Management, 261(8), 1415-1427.
Conger, RM. 1996. Black willow (Salix nigra ) use in phytoremediation techniques to remove the herbicide bentazon
from shallow groundwater. Master’s thesis, Louisiana State University
Brien, C. J., Berger, B., Rabie, H., & Tester, M. 2013. Accounting for variation in designing greenhouse experiments with
special reference to greenhouses containing plants on conveyor systems. Plant Methods, 9(5), 1746-4811
Westphal, A., Snyder, N., Xing, L. 2008. Effects of Inoculations with Mycorrhizal Fungi of Soilless Potting Mixes During
Transplant Production on Watermelon Growth and Early Fruit Yield. HortScience, 43(2), 354-360
LI-COR Biosciences. (2013). The LI-6400 Portable Photosynthesis System. Retrieved from
http://envsupport.licor.com/index.jsp?m=Current&spec=LI6400,Brochures&menu= Photosynthesis%20Systems
Xu, W., Cui, K. , Xu, A., Nie, L., Huang, J., & Peng, S. 2015. Drought stress condition increases root to shoot ratio via
alteration of carbohydrate partitioning and enzymatic activity in rice seedlings. Acta Physiologiae Plantarum, 37:9
