Mechanism of heat stress response in plantsDivyani1511
The document discusses the mechanism of heat stress response in plants. It begins with an introduction describing how rising global temperatures due to climate change pose a threat to crop productivity. It then discusses various effects of heat stress on plant morphology, anatomy, physiology and molecular processes. The molecular response involves heat shock proteins which act as molecular chaperones to protect proteins. Signaling pathways like Hsf-Hsp are also involved. Biotechnological approaches for developing heat tolerance in crops include marker-assisted selection and genetic engineering of heat shock factors. Examples of some high temperature tolerant crop varieties developed in India are also provided.
1) Salinity stress from high salt concentrations in soil can significantly reduce crop growth and yields. It is a major problem affecting over 6% of the world's total land and 20% of irrigated agricultural areas.
2) In India, about 6.73 million hectares of land are salt-affected, with states like Gujarat, Uttar Pradesh, and Maharashtra having the highest proportions. The key causes of soil salinity are accumulation of salts in arid areas, weathering of rocks, deposition of ocean salts, and poor irrigation water management.
3) Plants have different levels of tolerance to salt stress, from highly tolerant halophytes to very sensitive non-halophytes.
Commercial Plant growht regulators used in india Subhomay Sinha
This document discusses plant growth regulators (PGRs) and their uses in agriculture. It begins by defining PGRs as naturally occurring or synthetic chemicals that are applied to plants to produce desired effects by stimulating or inhibiting plant cell enzymes and metabolism. The five major classes of naturally occurring PGRs are described as auxins, gibberellins, cytokinins, abscisic acid, and ethylene. The roles and effects of auxins and gibberellins are then discussed in more detail. Commercial formulations of auxins and gibberellins are presented along with their recommended uses and concentrations for different crops.
Heat stress can damage plant growth and development by disrupting key processes like photosynthesis, membrane integrity, and protein function. Plants have developed several responses to heat stress including:
1) Producing heat shock proteins and antioxidants to protect cellular functions from heat damage.
2) Altering their morphology, anatomy, and phenology like earlier flowering to reduce heat exposure during sensitive periods.
3) Adjusting physiological processes like accumulating osmolytes to maintain water relations and membrane stability under heat stress.
4) Modulating hormones like ABA and ethylene that help regulate stress responses and signaling. Understanding these adaptation mechanisms can help improve crop heat tolerance through breeding.
The document is an assignment submitted by Brahmbhatt Jay H on plant growth regulators and their role in vegetable crop production. It discusses various types of plant growth regulators including auxins, gibberellins, cytokinins, abscisic acid, ethylene, morphactins, anti-transpirants, anti-auxins, ripening retardants, and plant stimulants. It provides details on their functions, examples, and effects on plant growth and development processes.
Next generation plant growth regulators in horticulture productionMohamed Farag
1. The document discusses various classes of plant growth regulators (PGRs) including auxins, gibberellins, cytokinins, ethylene, abscisic acid, and newer regulators like brassinosteroids, jasmonic acid, and salicylic acid.
2. It provides examples of each class and their roles in physiological processes and response to stresses. For example, jasmonic acid induces defense genes in response to damage and salicylic acid confers tolerance to heat, cold, and drought stresses.
3. A case study shows that pre-treating tomato and bean plants with salicylic acid or acetyl salicylic acid improves their survival after exposure to heat,
Role of new generation plant bioregulators in fruitSindhu Reddy
In order meet out the emerging consumer demand and challenges towards fruit production, there is the need to explore new interventions. One among that is use of new generation plant growth regulators in fruit crops. Plant growth regulators (PGR), recently name has been changed to plant bio-regulators (PBR’s) are defined as organic compounds, other than nutrients, that in small concentrations, affect the physiological processes of plants. There are five classical growth hormones which have the specific function in growth and development were already commercially exploited in fruit crops, but use of new generation growth regulators in fruit crops are recent and emerging trend. New generation PBR’s includes brassinosteroids, Jasmonate, salicylic acid, polyamines, karrikins and strigolactones and retardants such as 1-MCP and prohexodione-Ca. These are utilized in fruit crops starting from propagation to improving quality also including biotic and abiotic stress resistant. Hence, new generation plant growth regulators are an effective alternative for future fruit production combating major production challenges.
Mechanism of heat stress response in plantsDivyani1511
The document discusses the mechanism of heat stress response in plants. It begins with an introduction describing how rising global temperatures due to climate change pose a threat to crop productivity. It then discusses various effects of heat stress on plant morphology, anatomy, physiology and molecular processes. The molecular response involves heat shock proteins which act as molecular chaperones to protect proteins. Signaling pathways like Hsf-Hsp are also involved. Biotechnological approaches for developing heat tolerance in crops include marker-assisted selection and genetic engineering of heat shock factors. Examples of some high temperature tolerant crop varieties developed in India are also provided.
1) Salinity stress from high salt concentrations in soil can significantly reduce crop growth and yields. It is a major problem affecting over 6% of the world's total land and 20% of irrigated agricultural areas.
2) In India, about 6.73 million hectares of land are salt-affected, with states like Gujarat, Uttar Pradesh, and Maharashtra having the highest proportions. The key causes of soil salinity are accumulation of salts in arid areas, weathering of rocks, deposition of ocean salts, and poor irrigation water management.
3) Plants have different levels of tolerance to salt stress, from highly tolerant halophytes to very sensitive non-halophytes.
Commercial Plant growht regulators used in india Subhomay Sinha
This document discusses plant growth regulators (PGRs) and their uses in agriculture. It begins by defining PGRs as naturally occurring or synthetic chemicals that are applied to plants to produce desired effects by stimulating or inhibiting plant cell enzymes and metabolism. The five major classes of naturally occurring PGRs are described as auxins, gibberellins, cytokinins, abscisic acid, and ethylene. The roles and effects of auxins and gibberellins are then discussed in more detail. Commercial formulations of auxins and gibberellins are presented along with their recommended uses and concentrations for different crops.
Heat stress can damage plant growth and development by disrupting key processes like photosynthesis, membrane integrity, and protein function. Plants have developed several responses to heat stress including:
1) Producing heat shock proteins and antioxidants to protect cellular functions from heat damage.
2) Altering their morphology, anatomy, and phenology like earlier flowering to reduce heat exposure during sensitive periods.
3) Adjusting physiological processes like accumulating osmolytes to maintain water relations and membrane stability under heat stress.
4) Modulating hormones like ABA and ethylene that help regulate stress responses and signaling. Understanding these adaptation mechanisms can help improve crop heat tolerance through breeding.
The document is an assignment submitted by Brahmbhatt Jay H on plant growth regulators and their role in vegetable crop production. It discusses various types of plant growth regulators including auxins, gibberellins, cytokinins, abscisic acid, ethylene, morphactins, anti-transpirants, anti-auxins, ripening retardants, and plant stimulants. It provides details on their functions, examples, and effects on plant growth and development processes.
Next generation plant growth regulators in horticulture productionMohamed Farag
1. The document discusses various classes of plant growth regulators (PGRs) including auxins, gibberellins, cytokinins, ethylene, abscisic acid, and newer regulators like brassinosteroids, jasmonic acid, and salicylic acid.
2. It provides examples of each class and their roles in physiological processes and response to stresses. For example, jasmonic acid induces defense genes in response to damage and salicylic acid confers tolerance to heat, cold, and drought stresses.
3. A case study shows that pre-treating tomato and bean plants with salicylic acid or acetyl salicylic acid improves their survival after exposure to heat,
Role of new generation plant bioregulators in fruitSindhu Reddy
In order meet out the emerging consumer demand and challenges towards fruit production, there is the need to explore new interventions. One among that is use of new generation plant growth regulators in fruit crops. Plant growth regulators (PGR), recently name has been changed to plant bio-regulators (PBR’s) are defined as organic compounds, other than nutrients, that in small concentrations, affect the physiological processes of plants. There are five classical growth hormones which have the specific function in growth and development were already commercially exploited in fruit crops, but use of new generation growth regulators in fruit crops are recent and emerging trend. New generation PBR’s includes brassinosteroids, Jasmonate, salicylic acid, polyamines, karrikins and strigolactones and retardants such as 1-MCP and prohexodione-Ca. These are utilized in fruit crops starting from propagation to improving quality also including biotic and abiotic stress resistant. Hence, new generation plant growth regulators are an effective alternative for future fruit production combating major production challenges.
Drought stress and tolerance mechanisms in cropsMohaned Mohammed
Drought stress accounts for more crop production losses than any other factor. The presentation discusses the causes and effects of drought stress on plants and various tolerance mechanisms. It outlines that drought avoidance mechanisms include increased water absorption and transport, deep root systems, and reduced transpiration. Physiological responses include osmolyte accumulation, antioxidant production, and hormonal changes. Developing crops with drought tolerant traits through both conventional and molecular breeding approaches will be important for improving productivity under increasing drought conditions from climate change.
Drought and heat are major abiotic stresses that negatively impact plant growth and productivity. Drought stress reduces photosynthesis and induces stomatal closure and changes in gene expression and metabolism. Plants have developed various tolerance mechanisms including escape, avoidance, and tolerance. At the molecular level, plants respond to stresses through signaling pathways, changes in hormone levels like ABA, and expression of genes that encode protective proteins and osmoprotectants. Molecular responses are regulated by transcription factors that control stress-related gene expression. Engineering stress tolerance genes into crops holds promise to improve abiotic stress resistance.
This document summarizes a doctoral seminar on the influence of high temperature and breeding for heat tolerance. It covers several key points:
1) High temperatures can cause damage at the cellular level through protein denaturation and increased membrane fluidity. It also affects morphological, physiological and biochemical traits like photosynthesis and membrane stability.
2) Screening techniques are used to identify heat tolerant traits in germplasm, including cell membrane thermostability, chlorophyll content/fluorescence, and carbon isotope discrimination. Associations between traits and yield are also studied.
3) Breeding approaches aim to introduce heat tolerant genes from wild relatives through conventional breeding and marker-assisted selection. Isogenic lines are developed to
Abiotic stress management in vegetable cropsLabiba Shah
Abiotic stresses such as drought, salinity, temperature extremes, and mineral deficiencies limit crop productivity worldwide. The document discusses various abiotic stresses and their effects on plants. It provides details on injury mechanisms caused by each stress and tolerance mechanisms that have evolved in plants. It also discusses methods for screening and selecting stress-tolerant genotypes in breeding programs, including the use of wild relatives as sources of tolerance traits. Drought is estimated to account for over 50% of worldwide crop losses, while other stresses like salinity and high temperatures also significantly reduce yields. Breeding stress-tolerant crop varieties through selection and hybridization is important for sustainable agriculture.
This document provides an outline and overview of heat stress on plants. It begins with an introduction that defines heat stress and its effects on plant growth and development. It then discusses the perception of high temperature in plants and their responses, including morphological, physiological and molecular adaptations. The mechanisms of heat tolerance are also examined, particularly the role of heat shock proteins in protecting plant cells from damage. The document concludes that plants can adapt to heat stress through antioxidant protection and heat shock proteins maintaining protein stability.
Grafting is an ancient asexual propagation technique where the rootstock and scion from two plants are joined together to form a single plant. The production of grafted vegetable plants first began in Japan and Korea in the late 1920s with watermelons grafted onto pumpkin rootstocks. Now common in parts of Asia, Europe and the Middle East, grafting is used to improve traits like disease tolerance, abiotic stress resistance, and yield in important vegetable crops. Modern grafting methods include hole insertion grafting, tongue approach grafting and cleft grafting. Healing chambers are used to promote graft union formation and robotic grafting systems can produce hundreds of grafted plants per hour.
The document discusses salt stress in perennial fruit plants. It notes that salt stress affects 7% of the world's land area and is a problem for agricultural lands that are heavily irrigated. Salt stress can reduce plant germination, photosynthesis, vegetative growth, and reproductive growth/yield. Plants have developed various tolerance mechanisms including salt avoidance, exclusion, excretion, and osmotic adjustment using organic solutes and antioxidant defenses. Traditional approaches to managing salt stress include better irrigation practices and leaching excess salts from soils. Developing salt tolerant rootstocks and fruit varieties through conventional and biotechnological methods can also help cope with salt stress.
Salinity stress
Categorization of salt affected soils
CAUSES OF SALINITY IN SOIL
Salinity effects on Plants
Injuries due to salt stress
different strategies to avoid salt injury
salt tolerance
salt avoidance
salt evasion
halophytes
non halophytes
glycophytes
Breeding for salt tolerance
This document discusses several types of plant growth regulators including morphactins, anti-transpirants, anti-auxins, anti-oxidants, and growth retardants. Morphactins are substances that modulate plant morphogenesis and include derivatives of fluorine compounds. Anti-transpirants help reduce water loss from plants and include stomatal closing agents like phenyl mercuric acetate as well as film-forming and reflective materials. Anti-auxins inhibit the effects of auxins and examples provided are TIBA, NPA, and clofibric acid. Anti-oxidants protect plant cells from free radical damage and include vitamins A, C, and E. Growth retardants like CCC reduce shoot growth
plant drought effects, mechanisms and managementG Mahesh
This presentation provides an overview of plant drought stress, including its effects, mechanisms, and management strategies. Drought stress can impact plant growth, yield, water relations, photosynthesis, nutrient uptake, and cause oxidative damage. Plants have developed morphological, physiological and molecular mechanisms to tolerate drought, such as escaping dry conditions, reducing water loss through stomatal control, antioxidant production, and accumulating compatible solutes. The presentation also discusses strategies to manage drought, including improving crop genotypes and optimizing agronomic practices to enhance drought resistance.
Suitability of different fruit crops under different stress conditionsMANDEEP KAUR
This document summarizes research on the suitability of different fruit crops under salt stress conditions. It discusses several studies that evaluated:
1) The salt tolerance of grapevine cultivars grafted onto different rootstocks, finding the Salt Creek rootstock conferred the highest tolerance.
2) The effects of saline irrigation water on grapevine growth and survival, which significantly decreased with higher salt concentrations.
3) The relative salt tolerance of grapevine rootstocks to different chloride salts, determining the Dogridge rootstock accumulated the lowest chloride levels and was most tolerant.
4) The adaptation of grapevine varieties and rootstocks to salinity, aiming to correlate salt resistance with mineral content under salt treatments.
Global climate change and increasing climatic variability are recently considered a huge concern worldwide due to enormous emissions of greenhouse gases to the atmosphere and its more apparent effect on fruit crops because of its perennial nature. The changed climatic parameters affect the crop physiology, biochemistry, floral biology, biotic stresses like disease-pest incidence, etc., and ultimately resulted to the reduction of yield and quality of fruit crops. So, it is big challenge to the scientists of the world.
This document summarizes nutrient deficiencies and toxicities in various fruit crops. It describes the causes of deficiencies in crops like aonla, citrus, grapes, and avocado and the associated symptoms such as necrosis, splitting, chlorosis and burn. It outlines strategies for diagnosing deficiencies through soil and plant tissue analysis and provides guidance on optimal plant parts and stages for sampling. Treatment recommendations include fertilizer and foliar sprays tailored to the specific deficient nutrient.
Recent advances in hdp of citrus, guava, apricot and cherrysukhjinder mann
The document summarizes recent advances in high density planting (HDP) of citrus, guava, apricot and cherry. It discusses the principles and components of HDP, including adopting dwarfing rootstocks and varieties, efficient training and pruning, and suitable crop management practices. It also outlines some of the benefits of HDP over normal planting, such as maximizing yield per unit area and allowing for mechanization. However, it notes some constraints to adopting HDP systems, such as a lack of dwarf varieties and standardization of production technologies for different fruit crops.
1. Plants have developed three main adaptations to salinity stress: osmotic stress tolerance, sodium exclusion from leaves, and tissue tolerance to accumulated sodium and chloride in leaves.
2. Mechanisms of salinity tolerance include compartmentalization of ions, osmotic adjustment through compatible solutes, and exclusion of sodium from leaves.
3. Breeding efforts have developed salt tolerant varieties of crops like rice, wheat, mustard, and chickpeas through marker-assisted selection and identifying favorable quantitative trait loci.
This document provides an overview of a seminar on light interception by trees in relation to multistoried cropping systems. It discusses the introduction and benefits of multistoried cropping, including more efficient use of space, resources, and solar energy. Examples of multistoried cropping patterns combining trees, shrubs and herbaceous plants at different heights are provided. The document also covers principles of multistoried cropping systems, methods for measuring light interception, and the effects of light interception on crop growth and production.
PATHWAY OF MOVEMENT OF ASSIMILATES IN DEVELOPING GRAINS OF MONOCOTS AND DICOT...kartoori sai santhosh
PATHWAY OF MOVEMENT OF ASSIMILATES IN DEVELOPING GRAINS OF MONOCOTS AND DICOTS
CHEMICAL COMPOSITION OF SEEDS
STORAGE OF CARBOHYDRATES, PROTEINS AND FATS IN SEEDS AND THEIR BIOSYNTHESIS
Biochar impact on physiological and biochemical attributes of spinachGJESM Publication
Disastrous effect of nickel on spinach was discussed by number of authors but the effect of amendments like biochar with nickel on Spinacea oleraceaL. is not still discussed by any author of the world because biochar was used as soil amendments which play a vital role in reducing mobilization and uptake of nickel by spinach plants. As nickel contaminated plants are very harmful for the consumption by living organisms. Nickel can be gathered in agronomic soils by anthropogenic actions such as Ni-Cd batteries. In this study, the growth, physiological, photosynthetic and biochemical responses of Spinacia oleracea grown in Ni-spiked soil (0, 25, 50 and 100 mg Ni/Kg soil) at three levels of cotton-sticks-derived biochar “CSB” (0, 3 and 5 %) were evaluated. The results exposed significant decrease in growth, photosynthetic, physiological, and biochemical traits of S. oleracea when grown in Ni-polluted soil. However, this decrease was less pronounced in CSB amended soil. A steady rise in the MDA (0.66 µg/g to 2.08 µg g-1), ascorbic acid (1.24 mg/g to 1.57 mg/g)and sugar concentrations (1.73 mg/g to 2.16 mg/g)was observed with increased concentration of Ni. The increasing percentages of CSB from 3 % to 5 % decreased Ni concentrations in root and shoot of experimental plant. Higher production of chlorophyll, amino acids and protein with CSB amendment looked like alleviation in Ni toxicity. Therefore, it is concluded that, Ni toxicity and availability to the plants can be reduced by CSB amendments.
Drought stress and tolerance mechanisms in cropsMohaned Mohammed
Drought stress accounts for more crop production losses than any other factor. The presentation discusses the causes and effects of drought stress on plants and various tolerance mechanisms. It outlines that drought avoidance mechanisms include increased water absorption and transport, deep root systems, and reduced transpiration. Physiological responses include osmolyte accumulation, antioxidant production, and hormonal changes. Developing crops with drought tolerant traits through both conventional and molecular breeding approaches will be important for improving productivity under increasing drought conditions from climate change.
Drought and heat are major abiotic stresses that negatively impact plant growth and productivity. Drought stress reduces photosynthesis and induces stomatal closure and changes in gene expression and metabolism. Plants have developed various tolerance mechanisms including escape, avoidance, and tolerance. At the molecular level, plants respond to stresses through signaling pathways, changes in hormone levels like ABA, and expression of genes that encode protective proteins and osmoprotectants. Molecular responses are regulated by transcription factors that control stress-related gene expression. Engineering stress tolerance genes into crops holds promise to improve abiotic stress resistance.
This document summarizes a doctoral seminar on the influence of high temperature and breeding for heat tolerance. It covers several key points:
1) High temperatures can cause damage at the cellular level through protein denaturation and increased membrane fluidity. It also affects morphological, physiological and biochemical traits like photosynthesis and membrane stability.
2) Screening techniques are used to identify heat tolerant traits in germplasm, including cell membrane thermostability, chlorophyll content/fluorescence, and carbon isotope discrimination. Associations between traits and yield are also studied.
3) Breeding approaches aim to introduce heat tolerant genes from wild relatives through conventional breeding and marker-assisted selection. Isogenic lines are developed to
Abiotic stress management in vegetable cropsLabiba Shah
Abiotic stresses such as drought, salinity, temperature extremes, and mineral deficiencies limit crop productivity worldwide. The document discusses various abiotic stresses and their effects on plants. It provides details on injury mechanisms caused by each stress and tolerance mechanisms that have evolved in plants. It also discusses methods for screening and selecting stress-tolerant genotypes in breeding programs, including the use of wild relatives as sources of tolerance traits. Drought is estimated to account for over 50% of worldwide crop losses, while other stresses like salinity and high temperatures also significantly reduce yields. Breeding stress-tolerant crop varieties through selection and hybridization is important for sustainable agriculture.
This document provides an outline and overview of heat stress on plants. It begins with an introduction that defines heat stress and its effects on plant growth and development. It then discusses the perception of high temperature in plants and their responses, including morphological, physiological and molecular adaptations. The mechanisms of heat tolerance are also examined, particularly the role of heat shock proteins in protecting plant cells from damage. The document concludes that plants can adapt to heat stress through antioxidant protection and heat shock proteins maintaining protein stability.
Grafting is an ancient asexual propagation technique where the rootstock and scion from two plants are joined together to form a single plant. The production of grafted vegetable plants first began in Japan and Korea in the late 1920s with watermelons grafted onto pumpkin rootstocks. Now common in parts of Asia, Europe and the Middle East, grafting is used to improve traits like disease tolerance, abiotic stress resistance, and yield in important vegetable crops. Modern grafting methods include hole insertion grafting, tongue approach grafting and cleft grafting. Healing chambers are used to promote graft union formation and robotic grafting systems can produce hundreds of grafted plants per hour.
The document discusses salt stress in perennial fruit plants. It notes that salt stress affects 7% of the world's land area and is a problem for agricultural lands that are heavily irrigated. Salt stress can reduce plant germination, photosynthesis, vegetative growth, and reproductive growth/yield. Plants have developed various tolerance mechanisms including salt avoidance, exclusion, excretion, and osmotic adjustment using organic solutes and antioxidant defenses. Traditional approaches to managing salt stress include better irrigation practices and leaching excess salts from soils. Developing salt tolerant rootstocks and fruit varieties through conventional and biotechnological methods can also help cope with salt stress.
Salinity stress
Categorization of salt affected soils
CAUSES OF SALINITY IN SOIL
Salinity effects on Plants
Injuries due to salt stress
different strategies to avoid salt injury
salt tolerance
salt avoidance
salt evasion
halophytes
non halophytes
glycophytes
Breeding for salt tolerance
This document discusses several types of plant growth regulators including morphactins, anti-transpirants, anti-auxins, anti-oxidants, and growth retardants. Morphactins are substances that modulate plant morphogenesis and include derivatives of fluorine compounds. Anti-transpirants help reduce water loss from plants and include stomatal closing agents like phenyl mercuric acetate as well as film-forming and reflective materials. Anti-auxins inhibit the effects of auxins and examples provided are TIBA, NPA, and clofibric acid. Anti-oxidants protect plant cells from free radical damage and include vitamins A, C, and E. Growth retardants like CCC reduce shoot growth
plant drought effects, mechanisms and managementG Mahesh
This presentation provides an overview of plant drought stress, including its effects, mechanisms, and management strategies. Drought stress can impact plant growth, yield, water relations, photosynthesis, nutrient uptake, and cause oxidative damage. Plants have developed morphological, physiological and molecular mechanisms to tolerate drought, such as escaping dry conditions, reducing water loss through stomatal control, antioxidant production, and accumulating compatible solutes. The presentation also discusses strategies to manage drought, including improving crop genotypes and optimizing agronomic practices to enhance drought resistance.
Suitability of different fruit crops under different stress conditionsMANDEEP KAUR
This document summarizes research on the suitability of different fruit crops under salt stress conditions. It discusses several studies that evaluated:
1) The salt tolerance of grapevine cultivars grafted onto different rootstocks, finding the Salt Creek rootstock conferred the highest tolerance.
2) The effects of saline irrigation water on grapevine growth and survival, which significantly decreased with higher salt concentrations.
3) The relative salt tolerance of grapevine rootstocks to different chloride salts, determining the Dogridge rootstock accumulated the lowest chloride levels and was most tolerant.
4) The adaptation of grapevine varieties and rootstocks to salinity, aiming to correlate salt resistance with mineral content under salt treatments.
Global climate change and increasing climatic variability are recently considered a huge concern worldwide due to enormous emissions of greenhouse gases to the atmosphere and its more apparent effect on fruit crops because of its perennial nature. The changed climatic parameters affect the crop physiology, biochemistry, floral biology, biotic stresses like disease-pest incidence, etc., and ultimately resulted to the reduction of yield and quality of fruit crops. So, it is big challenge to the scientists of the world.
This document summarizes nutrient deficiencies and toxicities in various fruit crops. It describes the causes of deficiencies in crops like aonla, citrus, grapes, and avocado and the associated symptoms such as necrosis, splitting, chlorosis and burn. It outlines strategies for diagnosing deficiencies through soil and plant tissue analysis and provides guidance on optimal plant parts and stages for sampling. Treatment recommendations include fertilizer and foliar sprays tailored to the specific deficient nutrient.
Recent advances in hdp of citrus, guava, apricot and cherrysukhjinder mann
The document summarizes recent advances in high density planting (HDP) of citrus, guava, apricot and cherry. It discusses the principles and components of HDP, including adopting dwarfing rootstocks and varieties, efficient training and pruning, and suitable crop management practices. It also outlines some of the benefits of HDP over normal planting, such as maximizing yield per unit area and allowing for mechanization. However, it notes some constraints to adopting HDP systems, such as a lack of dwarf varieties and standardization of production technologies for different fruit crops.
1. Plants have developed three main adaptations to salinity stress: osmotic stress tolerance, sodium exclusion from leaves, and tissue tolerance to accumulated sodium and chloride in leaves.
2. Mechanisms of salinity tolerance include compartmentalization of ions, osmotic adjustment through compatible solutes, and exclusion of sodium from leaves.
3. Breeding efforts have developed salt tolerant varieties of crops like rice, wheat, mustard, and chickpeas through marker-assisted selection and identifying favorable quantitative trait loci.
This document provides an overview of a seminar on light interception by trees in relation to multistoried cropping systems. It discusses the introduction and benefits of multistoried cropping, including more efficient use of space, resources, and solar energy. Examples of multistoried cropping patterns combining trees, shrubs and herbaceous plants at different heights are provided. The document also covers principles of multistoried cropping systems, methods for measuring light interception, and the effects of light interception on crop growth and production.
PATHWAY OF MOVEMENT OF ASSIMILATES IN DEVELOPING GRAINS OF MONOCOTS AND DICOT...kartoori sai santhosh
PATHWAY OF MOVEMENT OF ASSIMILATES IN DEVELOPING GRAINS OF MONOCOTS AND DICOTS
CHEMICAL COMPOSITION OF SEEDS
STORAGE OF CARBOHYDRATES, PROTEINS AND FATS IN SEEDS AND THEIR BIOSYNTHESIS
Biochar impact on physiological and biochemical attributes of spinachGJESM Publication
Disastrous effect of nickel on spinach was discussed by number of authors but the effect of amendments like biochar with nickel on Spinacea oleraceaL. is not still discussed by any author of the world because biochar was used as soil amendments which play a vital role in reducing mobilization and uptake of nickel by spinach plants. As nickel contaminated plants are very harmful for the consumption by living organisms. Nickel can be gathered in agronomic soils by anthropogenic actions such as Ni-Cd batteries. In this study, the growth, physiological, photosynthetic and biochemical responses of Spinacia oleracea grown in Ni-spiked soil (0, 25, 50 and 100 mg Ni/Kg soil) at three levels of cotton-sticks-derived biochar “CSB” (0, 3 and 5 %) were evaluated. The results exposed significant decrease in growth, photosynthetic, physiological, and biochemical traits of S. oleracea when grown in Ni-polluted soil. However, this decrease was less pronounced in CSB amended soil. A steady rise in the MDA (0.66 µg/g to 2.08 µg g-1), ascorbic acid (1.24 mg/g to 1.57 mg/g)and sugar concentrations (1.73 mg/g to 2.16 mg/g)was observed with increased concentration of Ni. The increasing percentages of CSB from 3 % to 5 % decreased Ni concentrations in root and shoot of experimental plant. Higher production of chlorophyll, amino acids and protein with CSB amendment looked like alleviation in Ni toxicity. Therefore, it is concluded that, Ni toxicity and availability to the plants can be reduced by CSB amendments.
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.
Rice is one of the most important cereal crops of developing countries and the staple food of about 65% of the world’s population. The rice crops have been greatly disturbed by the heavy metals. The present study deals with the toxic effect of sodium arsenate on morphological and molecular variation through SDS-PAGE in 10 rice (Oryza sativa L.) varieties. Ten varieties of rice were grown under different concentration (25 ppm, 50 ppm and 100 ppm) of sodium arsenate against control. Morphological parameters like shoot length, root length, leaf area and biomass showed marked differences among ten rice varieties. The proteins were separated through SDS-PAGE gel electrophoresis and calculated their molecular weight. The morphological and molecular variations induced in rice varieties by arsenic stress provide a new insight leading to a better understanding of the heavy metal response in plants.
Article Citation:
John De Britto R, Mary Sujin R, Steena Roshan Sebastian and Dharmar K.
Toxic effect of arsenic on ten rice varieties.
Journal of Research in Agriculture (2011) 1(1): 011-016.
Full Text:
http://www.jagri.info/documents/AG0003.pdf
Rice is one of the most important cereal crops of developing countries and
the staple food of about 65% of the world’s population. The rice crops have been
greatly disturbed by the heavy metals. The present study deals with the toxic effect of
sodium arsenate on morphological and molecular variation through SDS
-
PAGE in 10
rice (
Oryza sativa
L.) varieties. Ten varieties of rice were grown under different
concentration (25 ppm, 50 ppm and 100 ppm) of sodium arsenate against control.
Morphological parameters like shoot length, root length, leaf area and biomass
showed marked differences among ten rice varieties. The proteins were separated
through SDS
-
PAGE gel electrophoresis and calculated their molecular weight. The
morphological and molecular variations induced in rice varieties by arsenic stress
provide a new insight leading to a better understanding of the heavy metal response
in plants.
ABSTRACT
The use of Spirulina as a nutraceutical has been popularized owing to its high essential amino acid, vitamin, carotenoid, chlorophyll content, antioxidant and antiinflamatory properties. This organism can also bioaccumulate and biosorb essential and non essential heavy metals. These properties have been exploited in this study using the organism, Spirulina platensis ARM 728. The fortification of the biomass in different concentrations of Selenium (10 ppm, 40 ppm and 100 ppm) and Zinc (1 ppm, 5 ppm and 10 ppm) was carried out and an increased content of proteins, chlorophyll, carotenoids, SOD, CAT and total antioxidant activity was seen. The biosorption and desorption capacity of the organism for antimony at 80 ppm was also seen with fair results.
Keywords: antioxidant properties, bioaccumulation, biosorption, heavy metals, Spirulina fortification.
The effect of rhizosphere growth promoter bacteria on enzymes activities of H...Innspub Net
Soils and accumulated materials are resources of heavy metals, which are available for absorbance by plants. One
of the potential methods for eliminating heavy metals from polluted places includes usage of resistance creature
to metals which are able to accumulate and absorb high amount of material. Present study was carried out in a
greenhouse format in completely accidental plots with 4 times repetition and 2 plants of Hordeum vulgare and Brassica napus. This experiment was done in 2011 in Islamic Azad University, Karaj branch. Variance analysis results showed significant effect of pb levels, growth promoters bacteria and interaction effects of them on capabilities of Superoxide dismutase (SOD), Catalase (CAT) and Glutathione peroxidase (GPX) enzymes (P<0.01). Get the full articles at: http://www.innspub.net/volume-4-number-10-may-2014/
The effect of rhizosphere growth promoter bacteria on enzymes activities of H...Innspub Net
Soils and accumulated materials are resources of heavy metals, which are available for absorbance by plants. One
of the potential methods for eliminating heavy metals from polluted places includes usage of resistance creature
to metals which are able to accumulate and absorb high amount of material. Present study was carried out in a
greenhouse format in completely accidental plots with 4 times repetition and 2 plants of Hordeum vulgare and Brassica napus. This experiment was done in 2011 in Islamic Azad University, Karaj branch. Variance analysis results showed significant effect of pb levels, growth promoters bacteria and interaction effects of them on capabilities of Superoxide dismutase (SOD), Catalase (CAT) and Glutathione peroxidase (GPX) enzymes (P<0.01).
This document summarizes a study on the effect of salinity stress from NaCl and CaCl2 on safflower seed germination. Safflower seeds were exposed to seven concentrations of NaCl or CaCl2 solutions, from 0 to 12 g/L. Salinity stress decreased all measured seed germination and seedling growth traits, including germination percentage and rate, radicle and plumule length and weight. Radicle was more sensitive to salinity than plumule. NaCl had a greater negative effect than CaCl2. The lowest salinity level of 2 g/L enhanced some traits, but higher concentrations increasingly inhibited germination and growth. Radicle dry weight may be a useful trait for screening safflower genotypes for
The document discusses a study on using seaweed to reduce the toxicity of industrial effluents. Seedlings of Cyamopsis tetragonoloba were treated with various concentrations of match and plate making effluents, which caused reductions in plant growth and biochemical characteristics. The effluents were then mixed with seaweed powder and the toxicity was reduced. When the plants were treated with the seaweed-treated effluents, their morphometric, pigment, and biochemical characteristics increased compared to treatment with effluents alone. The seaweed was found to effectively adsorb and reduce the toxicity of the effluents.
ODAP/BOAA: Its Genetics and Breeding Approaches in Lathyrus lathyrusSopan Zuge
This document summarizes a doctoral seminar on the genetic improvement of Lathyrus sativus (grasspea) to reduce its neurotoxic amino acid content. It discusses the nutritional value and uses of Lathyrus, but notes it contains the neurotoxin beta-N-oxalyl-L-alpha,beta-diaminopropionic acid (ODAP), which can cause the motor neuron disease lathyrism. Various breeding approaches that have been used to develop low-ODAP varieties are described, including germplasm evaluation, hybridization, mutation breeding, marker-assisted selection, transgenic methods, and somaclonal variation. Case studies on somaclonal variation in Lathyrus are presented
Abstract— Storage roots are important for the growth and development in plants because they provide nutrients, water, and energy storage. Storage roots are also modulating growth direction, disease resistance, and root formation at the cellular and molecular level through interactions of genes and gene networks. However, molecular mechanisms regulating storage root formation in plants are not fully understood. In this review, we have overviewed transcriptional regulation of storage root formation, proteomic regulation of storage root formation, ethylene regulation of storage root formation, auxin regulation of storage root formation, gene expression regulation of storage root formation, and metabolism regulation of storage root formation. We have reviewed the basic regulatory principles of storage root formation from the network of genomics to proteomics and metabolism in plants that will be valuable to research work in storage root growth and development regulation at the molecular level.
This document summarizes a study that manipulated ascorbic acid (vitamin C) biosynthesis pathways in tomato (Solanum lycopersicum) plants by expressing three genes involved in ascorbic acid production. GDP-mannose pyrophosphorylase (GMPase) from yeast, arabinono-1,4-lactone oxidase (ALO) from yeast, and myo-inositol oxygenase 2 (MIOX2) from Arabidopsis thaliana were independently expressed in tomato under the control of a constitutive promoter. Expression of GMPase increased ascorbic acid levels up to 70% in leaves, 50% in green fruit, and 35% in red fruit.
Physiological and molecular basis of drought tolerance in riceAlex Harley
This document summarizes a seminar on the physiological and molecular mechanisms of drought tolerance in rice. It discusses mechanisms such as osmoregulation through proline accumulation, antioxidant systems like ascorbate-glutathione pathways, and signaling molecules like ABA. It also describes quantitative trait loci (QTLs) linked to drought tolerance that have been identified, including qDTY12.1. Finally, it discusses transgenic approaches to improving drought tolerance by overexpressing genes involved in traits like root growth, osmoprotectant synthesis, and transcription factor regulation.
Research on Trivedi Effect -Impact of Biofield Treatment on Growth and Yield ...john henrry
Research done by Mahendra Trivedi - This study tested the impact of Trivedi Effect applied to lettuce and tomato seeds and transplants in commercial plantings with and without fertilizers and pesticides, in relation to yield, quality, and pest inhibition.to read research visit http://www.academicroom.com/article/impact-biofield-treatment-growth-and-yield-lettuce-and-tomato
Research on Trivedi Effect -Impact of Biofield Treatment on Growth and Yield ...Abby Keif
Research done by Mahendra Trivedi - This study tested the impact of Trivedi Effect applied to lettuce and tomato seeds and transplants in commercial plantings with and without fertilizers and pesticides, in relation to yield, quality, and pest inhibition. Read Complete research at: http://works.bepress.com/mahendra_trivedi/1/
Ethylene- and shade-induced hypocotyl elongation share transcriptome patterns...Debatosh Das
Plants have evolved shoot elongation mechanisms to escape from diverse environmental stresses such as flooding and vegetative shade. The apparent similarity in growth responses suggests possible convergence of the signalling pathways. Shoot elongation is mediated by passive ethylene accumulating to high concentrations in flooded plant organs and by changes in light quality and quantity under vegetation shade. Here we study hypocotyl elongation as a proxy for shoot elongation and delineated Arabidopsis hypocotyl length kinetics in response to ethylene and shade. Based on these kinetics, we further investigated ethylene and shade-induced genome-wide gene expression changes in hypocotyls and cotyledons separately. Both treatments induced a more extensive transcriptome reconfiguration in the hypocotyls compared to the cotyledons. Bioinformatics analyses suggested contrasting regulation of growth promotion- and photosynthesis-related genes. These analyses also suggested an induction of auxin, brassinosteroid and gibberellin signatures and the involvement of several candidate regulators in the elongating hypocotyls. Pharmacological and mutant analyses confirmed the functional involvement of several of these candidate genes and physiological control points in regulating stress-escape responses to different environmental stimuli. We discuss how these signaling networks might be integrated and conclude that plants, when facing different stresses, utilise a conserved set of transcriptionally regulated genes to modulate and fine tune growth.
1) The study investigated the effects of ethanol/potash extract of sorghum bicolor leaf sheath on serum electrolytes, liver, and kidney function in albino rats.
2) The extract significantly increased serum sodium and chloride ions but decreased potassium ion levels in a dose-dependent manner. It also increased serum creatinine and urea levels indicating potential kidney damage.
3) The extract decreased total protein and cholesterol levels but increased bilirubin at the highest dose, suggesting effects on liver function. There was also a progressive decrease in body weight with increasing extract doses.
Stress induzido por metais pesados Cd e Pb em feijoeiroMarcele Cannata
This document summarizes a study that evaluated the effects of increasing concentrations of cadmium (Cd) and lead (Pb) on bean plants (Phaseolus vulgaris L.) grown in nutrient solution. Bean plants were exposed to Cd concentrations from 0 to 0.5 mg/L and Pb concentrations from 0 to 10 mg/L. The study found that 0.1 mg/L of Cd reduced bean shoot dry matter by 45% and root dry matter by 80% compared to the control, while translocating 39.8% of Cd to the shoot. Exposure to 1 mg/L Pb translocated 5.7% to the leaves and 10 mg/L Pb reduced root and shoot dry matter by
Similar to Karrikin - A Promising Plant Growth Regulator for Agriculture (20)
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
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change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
ESPP presentation to EU Waste Water Network, 4th June 2024 “EU policies driving nutrient removal and recycling
and the revised UWWTD (Urban Waste Water Treatment Directive)”
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Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
Immersive Learning That Works: Research Grounding and Paths ForwardLeonel Morgado
We will metaverse into the essence of immersive learning, into its three dimensions and conceptual models. This approach encompasses elements from teaching methodologies to social involvement, through organizational concerns and technologies. Challenging the perception of learning as knowledge transfer, we introduce a 'Uses, Practices & Strategies' model operationalized by the 'Immersive Learning Brain' and ‘Immersion Cube’ frameworks. This approach offers a comprehensive guide through the intricacies of immersive educational experiences and spotlighting research frontiers, along the immersion dimensions of system, narrative, and agency. Our discourse extends to stakeholders beyond the academic sphere, addressing the interests of technologists, instructional designers, and policymakers. We span various contexts, from formal education to organizational transformation to the new horizon of an AI-pervasive society. This keynote aims to unite the iLRN community in a collaborative journey towards a future where immersive learning research and practice coalesce, paving the way for innovative educational research and practice landscapes.
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...Leonel Morgado
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
5. 5
1
2
3
4
5
6
7
8
9
Table of
Content
Introduction
Synthesis of karrikin from fire
Discovery and etymology of karrikins
Chemical structure of karrikin
Interaction with other hormones
Relation blw karrikins and strigolactone
Effects of karrikins on plants
Research evidences
Conclusion
6. • ‘Fire-followers’ or ‘Fire-ephemerals’.
• Heat, temperature and chemicals (Paul et al., 2007).
• Smoke - Stimulate the germination of seeds (Lange and Boucher, 1990 and
Halford 2010).
• Stable at high temperatures, water soluble, and very active in low concentrations
(Flematti et al., 2004).
6
Introduction - smoke
7. • Plant growth regulators
• Water soluble, thermostable, long lasting, down to
10−9 mol/l
• Molecular weight : 150.1
• Solubility : Chloroform and methanol
• Molecular formula: C8H6O3
• IUPAC name: 3-methyl-2H-furo[2,3-c]pyran-2-one
7
Introduction - karrikins
Structure of karrikin
8. 8
(Flematti et al., 2015)
Bush fire
Smoke - Karrikins
After rain - Seed germination
Anthocercis littorea
Anthocercis littorea
9. 9
Discovery and
etymology of
karrikins
Smoke stimulate seed
germination (De Lange and
Boucher, 1990)
Nitric acid - responsible for
germination
Butenolide - karrikinolide
3-methyl- 2H-furo[2,3-c]pyran-
2-one) (Flematti et al., 2004)
Smoke - ‘karrik’ in Aboriginal
term - Karrikins
10. 10
Synthesis of karrikin from fire
Carbohydrate
Sugar Karrikins
Cellulose
I. hypothesis - Maillard reaction
(carbohydrate and amino acids)
(Light et al., 2005)
II. hypothesis - Cellulose (Halford,
2010).
• Not carried for long distances in smoke (Nelson et
al., 2012).
• Melting point - 118–119 ◦C
11. 11
Karrikin chemical structure
• C, H and O
• KAR1, KAR2, KAR3, KAR4, KAR5 & KAR 6
• Five-membered butanolide ring
• six-membered pyran ring (Waters et al.,
2014).
• 3-methyl-2H-furo[2,3-c]pyran-2-one
(Flematti et al., 2004)
• 3,4,5-trimethylfuran-2(5H)-one (Light et al.,
2010)
TMB
12. 12
Cellulose-
derived
smoke
• Mass and light spectrometric data
• Gas chromatography mass spectrometry
(Flematti et al., 2004).
Smoke-
saturated
water
• Gas chromatography-mass spectrometry
• Nuclear magnetic resonance (NMR)
spectroscopy. (Van Staden et al., 2004)
Quantification of karrikin
KARs - Ultrahigh-performance liquid chromatography-tandem mass spectrometry
(Hrdlicka et al., 2019).
15. • KAR1 - very low concentrations – Production of phytohormones (Chiwocha et al., 2009).
• KAR1 stimulates the germination of light- sensitive seeds - GA (Merritt et al., 2005).
• GA biosynthesis enzymes - GA3ox1 and GA3ox2.
• Endogenous levels of ABA, GA1, GA3 and GA4 not altered.
• Reduces the amounts of exogenous GA3 and GA4 in seeds of Stylidium maritimum
15
Karrikin interaction with other hormones
16. - Karrikins - Cellulose
- Strigolactone - Carotenoids
KAR and SL - butenolide molecule
16
Relation between karrikin and strigolactone
20. • Seed germination in more than 1200 species from 80 genera (Dixon et al., 2009).
• Annual, perennial and shrub life forms (Roche et al., 1997).
• Germination in laboratory and field conditions (Baskin and Baskin, 1998).
• Flowering plants, conifers & horticultural crops - Respond to karrikins (Stevens, 2007
and Nelson, 2012).
• Reactive to smoke in all continents (excluding Antarctica) (Pierce et al., 1995).
20
Effects of smoke & karrikin on plant growth and development
21. • Phylogenetically plant groups - Gymnosperms (Dixon et al., 2009)
Angiosperms (Baskin and Baskin, 1998)
• Variety of ecosystems - Mediterranean vegetation (Catav et al., 2012)
Desert (Pierce et al., 1995)
Alpine (Smedley et al., 1997)
Wetlands (Chiwocha et al., 2009)
• A. thaliana, S. esculentum, Z. mays, O. sativa, L. sativa - non fire followers (Van Staden
et al., 2006).
21
Contd...
22. • Germination of Arabidopsis seeds under favorable conditions (Wang et al., 2018).
• Improved tomato seedling development in temperature extremes (Jain et al., 2006) .
• KAR2 is most active in Arabidopsis (Nelson et al., 2009).
• KAR4 is inactive in Arabidopsis - Stimulate seed germination in L. sativa and S.
orbiculatum (Nelson et al., 2009).
22
Contd...
23. • Arabidopsis - Treated with KAR- ABA level not influenced.
• Avena fatua kernels - Treated with KAR- 1/3 decrease in level of ABA (Nelson et al.,
2009).
• Arabidopsis - Influence chlorophyll concentration (Akeel et al., 2019).
• Carrot - Increase chlorophyll content and net photosynthesis rate, increased stomatal
conductance.
23
Contd...
24. • Arabidopsis - Lower anthocyanin content.
• Carrot roots- Increased Ascorbic acid and β-carotene content (Li et al., 2017).
• KAR - Regulate germination and hypocotyl elongation (Soundappan et al., 2015).
• SL – Root hair development, root growth diameter (Aguilar et al., 2019).
24
KAR SL
1. Regulation of
Leaf morphology
2. Influence the
density of lateral
roots
Contd...
26. 26
Table1: Effects of karrikins (KARs) on the growth and development of
agricultural and horticultural crops
Plant Conc
(M)
Application Examined features Effect
of KAR
Reference
Rice
(Oryza sativa L.)
10−10
–10−8
Grown in Petri
dishes with
KAR1 solution
Seedling weight, vigor index, root
and shoot length, no. of lateral
roots
+ (Kulkarni
et al., 2006)
Tomato
(Lycopersicon
esculentum Mill.)
10−7 Grown in Petri
dishes with
KAR1 solution
Germination 0 (Jain et al.,
2006)
% of abnormal seedlings -
Hypocotyl and radicle length +
Weight of 10 embryonic axis +
27. 27
Plant Conc
(M)
Application Examined features Effect
of
KAR
Reference
Tomato (Lycopersicon
esculentum Mill.),
Okra (Abelmoschus
esculentus L.),
Bean (Phaseolus
vulgaris L.)
Maize (Zea mays L.)
10−7 Tomato, okra, bean and
maize seeds were grown
in Petri dishes with KAR1
solution,
Root and shoot length + (Van Staden
et al., 2006)
Seedling weight of
tomato, okra and maize
+
Seedling weight of bean
vigor index
0
Carrot
(Daucus carota L.
10−10 -
10−7
Seeds presoaked in KAR1
solution for 12 h
Germination, plant height + (Akeel et
al., 2019)
Length, diameter, fresh
and dry weight of root
+
(Fv/Fm), (PN), (gs), total
chlorophyll content
+
Carotenoids, β-carotene
and vitamin C of root
+
28. 28
Table2: Responses of weed seeds to smoke water and KAR1
Family Species Smoke
water
KAR1 References
Amaranthaceae Chenopodium album + 0 Daws et al., (2007)
Asteraceae Chrysanthemum segetum + + Daws et al., (2007)
Senecio jacobinae 0 + Daws et al., (2007)
Brassicaceae Brassica tournefortii + + Stevens et al., (2007)
Sinapis alba 0 + Daws et al., (2007)
Sisymbrium orientale - + Stevens et al., (2007)
Caryophyllaceae Stellaria media + + Daws et al., (2007)
Malvaceae Malva neglecta 0 + Daws et al., (2007)
Papaveraceae Papaver rhoeas 0 + Daws et al., (2007)
Poaceae Avena fatua - + Daws et al., (2007)
Hordeum leporinum + + Stevens et al., (2007)
Sorghum halepense 0 + Daws et al., (2007)
29. • Smoke water- Germination of garden and horticultural seeds.
• Aerosol smoke - Nurseries & landscape restoration operations (Dixon et al., 2009).
• Karrikinolide - 5 – 20 g per hectare (Stevens et al. (2007). (Arctotheca calendula,
Brassica tournefortii, & Raphanus raphanistrum)
29
Uses
Smoke water
32. Treatment details
• SSW (25.8 µg L−1, 51.6 µg L−1,103.2 µg L−1 and 258.0 µg L−1)
• KAR1 (0.015 µg L−1, 0.150 µg L−1, 1.501 µg L−1 and 15.013 µg L−1)
Material and methods
• KAR1 was purchased from Toronto Research Chemicals, Canada.
• SSW – Apparatus
*
Evidence 1: Smoke-saturated water and karrikinolide modulate on
germination, growth, photosynthesis and nutritional values of carrot (Daucus
carota L.)
(Akeel et al., 2019)
33. 33
Fig 1. Effect of SSW and KAR1 on germination percentage (%)
SSW - Control, 25.8 µg L−1, 51.6 µg L−1,103.2 µg L−1 and 258.0 µg L−1
KAR1 - Control, 0.015 µg L−1, 0.150 µg L−1, 1.501 µg L−1 and 15.013 µg L−1
(Akeel et al., 2019)
34. 34
Fig 2. Effect of SSW and KAR on net photosynthesis
SSW - Control, 25.8 µg L−1, 51.6 µg L−1,103.2 µg L−1 and 258.0 µg L−1
KAR1 - Control, 0.015 µg L−1, 0.150 µg L−1, 1.501 µg L−1 and 15.013 µg L−1
(Akeel et al., 2019)
35. 35
Table 3: Effect of SSW on growth parameters of carrot
(Akeel et al., 2019)
36. 36
Table 4: Effect of KAR 1 on growth parameters of carrot
(Akeel et al., 2019)
37. 37
Fig 3. Effect of SSW and KAR1
on nutritional value of carrot
(Akeel et al., 2019)
38. 38
Evidence 2: Karrikins identified in biochars indicate post fire chemical cues
can influence community diversity and plant development
Material and methods
(Kochanek et al., 2016)
39. 39
Fig 4. The yield of karrikinolide (KAR1) isolated from biochar
(Kochanek et al., 2016)
40. 40
Fig 5. Effect of KAR in biochar on tomato
(Kochanek et al., 2016)
41. 41
Evidence 3. Role of smoke stimulatory and inhibitory biomolecules
in phytochrome-regulated seed germination of Lactuca sativa
(Gupta et al., 2019)
Fig 6. Effects of SW, KAR1 & TMB on
germination and ABA levels
Fig 7. Effects of SW, KAR1 & TMB on
hydrolytic enzymes
42. Material and method
0 - 2 cm,
2 - 4 cm,
4 - 6 cm,
6 - 8 cm
42
Evidence 4. Karrikinolide residues in grassland soils following fire
Treatment Conditions under which soil core samples
were collected
No-burn Soil cores collected from no-burn plots
Burnt Soil cores collected from burnt plots
Adjacent
5 m
Soil cores collected from unburnt (5 meters
away)
Adjacent
10 m
Soil cores collected from unburnt (10 meters
away)
(Ghebrehiwot et al., 2013)
43. 43
Table 5: The effect of various soil extracts obtained from four different burning treatments on
germination of Lactuca sativa seeds
Treatments Germination (%) Detected KAR1 (nmol/g soil) Detected TMB (nmol/g soil)
0–2 cm
No-burn 18.7 2.09 104
Burnt 94.7 3.98 276
Adjacent 5 m 53.2 2.45 295
Adjacent 10 m 32 2.52 310
2-4 cm
No-burn 27.7 1.92 127
Burnt 86.7 3.15 380
Adjacent 5 m 33.2 2.60 339
Adjacent 10 m 37.7 2.07 228
4-6 cm
No-burn 20.2 1.92 146
Burnt 72.2 2.46 370
Adjacent 5 m 45.7 2.74 307
Adjacent 10 m 35.2 2.12 206
6-8 cm
No-burn 19.2 1.88 152
Burnt 65.7 2.31 387
Adjacent 5 m 47.7 2.42 334
Adjacent 10 m 37 2.05 283
Ghebrehiwot et al., 2013
44. 44
(Shah et al., 2020)
Evidence 5: Karrikin improves osmotic and salt stress tolerance via the
regulation of the redox homeostasis in the oil plant Sapium sebiferum
Fig 8. Effect on KAR 1 on germination under stress
45. 45
(Shah et al., 2020)
Fig 9. Effect of stress on antioxidant enzymes
46. Advantage
• Land restoration purpose
• Efficient in weed control management
• Arid and semi Arid region
Disadvantage
• Mode of action
• Metabolism is unclear
46
Pros & Cons
47. 47
Conclusion and future perspective
• Plant hormone
• Karrikin can be used as an important management tool for land rehabilitation
and weed control.
• Genomic approaches are the next step towards exploring the mechanism of
action of karrikin.
48. • Akeel, A.; Khan, M.M.A.; Jaleel, H.; Uddin, M. Smoke-saturated Water and Karrikinolide Modulate Germination,
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1401.
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51
Fire is a common disturbance that affects a large proportion of ecosystems (Bond & Keeley 2005; Chuvieco, Giglio, & Justice 2008) and a significant driver of global plant diversity (Pausas & Ribeiro 2017). Even though ∗Corresponding author. E-mail address: sertercatav@mu.edu.tr (S¸.S. C¸ atav). most current fires have an anthropogenic origin, wildfires have affected plant community dynamics since the Paleozoic time (Glasspool, Edwards, & Axe 2004; Pausas & Keeley 2009). Therefore, wildfires have been recognized as a natural phenomenon in terrestrial ecosystems (Keeley, Bond, Bradstock, Pausas, & Rundel 2012), and many plant species have evolved adaptive traits to persist in fire-prone environments. Resprouting from basal lignotubers, serotiny, enhanced flammability, post-fire flowering
Agriculture of the twenty-first century must face new challenges, which require novel solutions
10−10–10−7 M. It was found to be neither toxic nor geno
toxic at 3 × 10−10–10−4 M (Light et al. 2009),
. We now understand
that a group of butenolide compounds isolated from smoke, the first member of which was identified
independently by two researchers’ teams [7,8],
Phytohormones play a dominant role in regulating seed
germination and seedling establishment. Gibberellins (GA) can
break seed dormancy and induce germination (Yamauchi et al.,
2004), while abscisic acid (ABA) can promote seed dormancy and
delay germination (Ali-Rachedi et al., 2004). Auxin [indoleacetic
acid (IAA)] is also involved in regulating seed dormancy (Liu
et al., 2013). Furthermore, IAA has been demonstrated to be
an important regulator in the plant shade avoidance syndrome
that adversely affects seedling development and crop yield (Casal,
2013a; Gommers et al., 2013; Procko et al., 2014). In addition
to phytohormones, other chemical compounds have the ability
to regulate plant growth and development, such as nitrogen
oxide and reactive oxygen species (ROS), both of which have
been demonstrated to regulate seed dormancy and germination
(Bethke et al., 2006; Oracz et al., 2007, 2009; Oracz and Karpi´nski,
2016).
In 2004, chemists purified 3-methyl-2H-furo [2, 3-c] pyran-
2-one from the smoke of burning plant material (Flematti
et al., 2004). Subsequently, several analogs to 3-methyl-2H_x0002_furo [2, 3-c] pyran-2-one were found and collectively named as
karrikins (Flematti et al., 2007; Dixon et al., 2009).
The differences between the six known KARs are
based on methyl substitutions
Moreo_x0002_ ver, smoke water tends to have a ‘dual regulatory’ efect
on germination, as lower concentrations have a germi_x0002_ nation-promoting efect,
KARs are the major germination promoting compound found in smoke, and the KAR receptor is
present in all phylogenetic taxa of plants, including mosses, liverworts, or green algae [13]. Therefore,
the germination of smoke-responsive species is very likely enhanced by KARs
Schematic diagram showing diverse cellular responses to plant-derived smoke. Plantderived smoke triggers regulation of various metabolic processes resulting in acceleration of seed germination and other growth processes. Upward and downward arrows indicate increased and decreased metabolic processes in response to plant-derived smoke, respectively. The dashed lines represent the possible relationship between smoke induced changes at molecular level and their effects. Abbreviations are as follows: K/PDS, karrikins/plant-derived smoke; KAI2, α/β hydrolases receptors of karrikins; MAX2, F-box subunit of a SCF class of E3 ubiquitin-protein ligase complex; SMAX1, a growth suppressor protein; a
Under
abiotic stresses, applications of karrikins did not increase the endogenous abscisic acid level but altered the expression of several ABA signaling genes, such as SNF1-
RELATED PROTEIN KINASE2.3, SNF1-RELATED PROTEIN KINASE2.6, ABI3, and
ABI5, suggesting potential interactions between karrikins and ABA signaling in the
SNF1-
RELATED PROTEIN KINASE2.3, SNF1-RELATED PROTEIN KINASE2.6, ABI3, and
ABI5
, KAR1 is ~10-fold more effective than KAR2 in Grand Rapids lettuce, and 100-fold more effective in S. orbiculatum (Flematti et al. 2007
KAR1 was also shown to improve germination of tomato seed and subsequent seedling vigour when grown at low (10 C) or high (40 C
KAR2 stimulates germination of Arabidopsis seeds under favorable conditions, but it can inhibit
germination in the presence of osmolytes or at elevated temperature. KAI2 signaling may inhibit
germination under unfavorable conditions as protection against abiotic stress [60]. However,
germination and seedling growth of tef, an African cereal crop, under high temperature, and low
osmotic potential were observed to be enhanced by KAR1 treatment [61]. The enhanced germination
and improved tomato seedling development in temperature extremes connected with KAR1 utilization
were also reported [62]. These facts show that the reactions of a model plant and crops can be different.
The level of ABA in imbibed seeds of Arabidopsis was not affected by KARs treatment [53]. That
was not a case of Avena fatua kernels treated by KAR1, which showed a one-third decrease in the level
of ABA after 16 hours of imbibition
KAR signaling can also influence secondary metabolism. Kai2 mutant of Arabidopsis has lower
anthocyanin content as a result of transcription misregulation of the anthocyanin biosynthesis
pathway [71]. Ascorbic acid and β-carotene content were increased in carrot roots grown from KAR1
primed seeds [73]. The content of tashinone I, pharmacologically active terpenoid, was significantly
increased in hairy roots of Salvia miltiorrhiza by a signaling pathway involving nitric oxide and jasmonic
acid [75
Germination of Arabidopsis seeds and growth of seedlings in
response to karrikin. Arabidopsis thaliana seeds with primary dormancy
incubated for seven days on water-agar without karrikin (KAR)
germinate very poorly whereas those with KAR germinate readily
(top row). Seedlings germinated on nutrient medium and grown
in low light for seven days without KAR have long hypocotyls whereas
those with KAR have short hypocotyls and larger cotyledons
(bottom row). Images from the author’s laboratory
The realisation that many plant species respond to karrikins
led to the discovery that seeds of Arabidopsis thaliana can
respond [5]. Arabidopsis is the geneticist’s dream because of
the resources and knowledge that are available. Arabidopsis
seeds with a small amount of dormancy will respond to
KAR1 or KAR2, provided that there is no nitrate present,
which causes seeds to germinate regardless of the karrikin.
Selection of Arabidopsis mutants that fail to respond to
karrikins led to the discovery of two genes that are essential
for karrikin action. One gene, named MORE AXILARY
GROWTH2 (MAX2), was already known for its role in
responses to strigolactone hormones [13], while the other,
KARRIKIN-INSENSITIVE2 (KAI2), was similar to the gene
coding for the strigolactone receptor, known as DWARF14
[11]. These discoveries led to the idea that karrikins simply
mimic strigolactones, because they both have a butenolide
ring (Fig. 2). We now know that this is not the case in
Arabidopsis. Karrikins and strigolactones are perceived
separately and the plant responds differently to the two
classes of compound, but the two systems are obviously
very closely related [11]. Formally we still do not know if
the mode of action of karrikins in fire-followers is the same
as that in Arabidopsis, but all plants apparently contain a
KAI2 gene, so it seems likely
Utilization of KARs in dose 2–20 g haa 1 as weed control measure was proposed for agriculture [16].
Such use of KARs seems to be highly improbable as the cost of KARs would have to decrease thousands
fold to reach an affordable level, and, even then, economic benefit for farmers would be questionable.
More likely, KARs can be used as a priming agent for seeds of agricultural and horticultural crops in
order to enhance germination and early seedling growth to establish a steady field under conditions of
climate change
Measurements of karrikins in soil are technically very challenging but seed-germination bioassays can be used to detect activity, one study suggesting that active compound(s) can persist in the soil for over seven years after a fire [Preston and Baldwin, 1999]. Karrikins are unstable in ultraviolet light [Scaffidi et al., 2012] so they might be expected to decay rapidly in natural sunlight; however, smoke contains many aromatic 0compounds that can absorb ultraviolet light and could protect karrikins by acting as organic ‘sunscreens’. On the other hand, karrikins can be washed away by rain and elute through sandy soils relatively quickly, so their concentration will steadily decline.
The active compound(s) can persist in the soil for over seven years after a fire .
Karrikins are unstable in ultraviolet light [Scaffidi et al., 2012] so they might be expected to decay rapidly in natural sunlight; however, smoke contains many aromatic compounds that can absorb ultraviolet light and could protect karrikins by acting as organic ‘sunscreens’.
On the other hand, karrikins can be washed away by rain and elute through sandy soils relatively quickly, so their concentration will steadily decline. (author)
r germination. Plants were grown in a peat mixture without
biochar (control) or with peat replaced at 3, 10 or 30% by either a green waste biochar high in KAR1 or a sugarcane biochar low in KAR1. All mixtures
contained fertiliser to neutralise potential nutritional aspects of biochar [19]. Values represent means ± SEM (n = 5 biological replicates). Analysis of
variance and means tested the effect of biochar type and rate of application on (a) shoot length; (b) hypocotyl length; (c) leng
Effects of SW, KAR1, and TMB on germination (n 5 4) and
ABA (n 5 3) levels in cv Grand Rapids lettuce seeds under different light
conditions for 24 h at 25°C. After 3 h of incubation in the dark, seeds
were exposed to R or FR light treatment for 1 h and were replaced in the
dark. Bars (germination 6 SE) and symbols (ABA 6 SE) for each light
condition with different letters are signifificantly different according to
Bonferroni correction (P , 0.05). DW, Dry weight.
Now it is widely accepted by the plant physiologist that karrikins found in plant burning smoke has the ability to stimulate seed germination. Identification of these compounds helps to understand the possible effects on ecosystems and important tool for further investigation. This is of rising importance increased human activity and increased demands for food are increasing the frequencies and distribution of fires. However, global warming and precipitation changes are predicted to increase the frequency of wildfires (Pechony and Shindell 2010). Karrikins can be used as an important management tool for land rehabilitation and weed control. It is also to find that how stable they are in the soil and they are metabolized by plants and micro-organisms, and how they affect other organisms. Genomic approaches are the next step towards exploring the mechanism of action of karrikins. An important criterion to further find out that does the time of exposure to smoke have the influence on germination? The study of adoptability ability of a karrikin exposed species to different environmental stress (such as – drought, salt
and temperature stress) conditions is also important.