Ratnakumar Pasala | ICAR-Indian Institute of Oilseeds Research (original) (raw)

Papers by Ratnakumar Pasala

Research paper thumbnail of Source and sink traits and their relationship under deficit soil moisture stress conditions in an indeterminate crop: sesame (Sesamum indicum L.)

Research paper thumbnail of Influence of sowing environments on yield of sesame genotypes under shifting weather conditions of Deccan Plateau (Telangana)

Journal of Oilseeds Research

Climate change poses a challenge to sustainability of agricultural ecosystems and in turn the soc... more Climate change poses a challenge to sustainability of agricultural ecosystems and in turn the social and economic development, livelihoods of communities in the world and India is no exception. Sesame is an important oilseed crop that has nutritional components such as lignans (antioxidant), sesamol along with tocopherols. This crop is grown under varied climatic conditions in the country even though it is highly sensitive to thermal regimes. Therefore, identifying or breeding sesame varieties with adaptation to wider ecological regions with high yield potential is the need of the hour. To identify high yielding sesame genotypes under shifting weather conditions of Deccan Plateau, an experiment was conducted with different dates of sowing. The sowing dates were designed in such a way that itconsidered the present cropping situation where it is grown after the harvest of the kharif crop. A set of popular farmer preferred sesame varieties that are generally grown in different sesame g...

Research paper thumbnail of Role of Plant Based Edible Oils for Human Diet

In India there are seven edible oil seed crops, namely groundnut, rapeseed & mustard, soybean, su... more In India there are seven edible oil seed crops, namely groundnut, rapeseed & mustard, soybean, sunflower, sesame, safflower and niger, blessed by the benefit of the diverse agro-climatic areas. Oilseeds are important segment of tropical agriculture as they provide access to nutrition through protein and oil to humans and livestock. Edible oils are crucial for human nutrition, as they are energy dense with a high fat content. Human body needs some of the vital acids like Poly Unsaturated Fatty Acids (PUFA), which are not synthesized by the human body on its own, which obligates us to take from external sources. As vegetable oils are excellent source for PUFA, Mono-unsaturated fatty acids, Vitamins and others, an attempt was made to highlight the core health benefits of major vegetable oils.

Research paper thumbnail of Analysing the SPAD dynamics of water-stressed vs. well-watered sesame (<i>Sesamum indicum</i> L.) accessions and establishing their relationship with seed yield

PeerJ, Jan 18, 2023

Background. The chlorophyll content is susceptible to deficit moisture stress and may affect the ... more Background. The chlorophyll content is susceptible to deficit moisture stress and may affect the plant yield. Leaf chlorophyll content is directly related to tolerance and higher productivity under deficit moisture stress (WS). The SPAD meter is an excellent tool for rapid analysis of crop chlorophyll content. Therefore, establishing a relationship between leaf chlorophyll content and seed yield is crucial in sesame, particularly under deficit moisture stress. Methods. Seeds of 37 sesame genotypes with checks were used in this study. These genotypes were mostly landraces, adapted to different agro-ecological zones in India. The selected genotypes were evaluated under well water (WW) and deficit moisture stress (WS) conditions. The SPAD readings were recorded ten (10) times each at every seven days intervals from the juvenile/first bud (30-35 days after sowing) to ripening/ physiological maturity (95-100 days after sowing) stage. This study aimed to identify the association between leaf SPAD readings (recorded at 7-days interval) and seed yield of sesame genotypes. Results. The analysis of variance revealed the presence of significant variation in SPAD readings due to treatment (WW and WS), genotypes, and their interaction effects. The SPAD readings at all stages were positively correlated with seed yield in both WW and WS. High values of correlation coefficients were observed at 52 (r: 0.672) and 59 (r: 0.655) DAS under WS; whereas at 59 (r: 0.960), 66 (r: 0.972) and 73 (r: 0.974) DAS under WW at one percent significance level (p < 0.01), which coincided with the mid-bloom stage of the sesame crop. The best-fit multiple regression model revealed that the dependence of sesame seed yield is significantly influenced by SPAD reading at 52 DAS under WS and 59 to 73 DAS under WW. Both these models provide a good fit with the chi-squared test, which compares the predicted and observed yield.

Research paper thumbnail of Source and sink traits and their relationship under deficit soil moisture stress conditions in an indeterminate crop: sesame (<i>Sesamum indicum</i> L.)

Plant Production Science, Apr 23, 2023

Research paper thumbnail of Physiological traits and indices to identify tolerant genotypes in sesame (Sesamum indicum L.) under deficit soil moisture condition

Research paper thumbnail of Morphophysiological responses and tolerance mechanisms of Xanthium strumarium to manganese stress

Ecotoxicology and environmental safety, Jan 15, 2018

Effective phytoremediation of manganese (Mn) requires the careful selection of a species that has... more Effective phytoremediation of manganese (Mn) requires the careful selection of a species that has a relatively high manganese tolerance. Exploring the physiological mechanisms related to Mn stress responses is crucial for identifying and employing species for Mn phytoremediation. Xanthium strumarium is a species that can accumulate high levels of Mn, thus it is a candidate species for Mn-phytoremediation. To reveal the tolerance mechanisms of this species to manage Mn stress, the morphological, physiological, and biochemical responses of seedlings grown in water cultures under six different Mn concentrations were analyzed. The results showed that X. strumarium can accumulate high levels of Mn, even as plant growth was inhibited by rising Mn concentrations. Malondialdehyde (MDA) content increased and catalase (CAT) activity decreased along with the increased Mn concentrations, while soluble protein and proline content, as well as the superoxide dismutase (SOD) and peroxidase (POD) en...

Research paper thumbnail of Analysing the SPAD dynamics of water-stressed vs. well-watered sesame (<i>Sesamum indicum</i> L.) accessions and establishing their relationship with seed yield

Research paper thumbnail of Morpho-physiological, quality traits and their association with seed yield in sesame (Sesamum indicum L.) indigenous collection under deficit moisture stress

Plant Physiology Reports, 2021

A field experiment was conducted to investigate the effect of deficit moisture stress on eleven s... more A field experiment was conducted to investigate the effect of deficit moisture stress on eleven sesame genotypes viz., IC-132171, IC-132186, IC-204445, IC-131500, IC-132207, IC-205471, IC-203962, IC-205353, IC-96229, and IC-204966 along with a national check (GT-10). The deficit moisture stress (WS) was imposed for a period of 50–55 days from flowering to physiological maturity. The morphological, physiological, and yield traits under WS significantly decreased in comparison with irrigated conditions (WW). Based on the mean trait performance studied among the genotypes, IC-204966 was found significantly superior with respect to plant height, capsules number, seed weight, total dry matter, leaf area, relative water content and reduced canopy temperature under WS conditions. The correlation analysis of different traits with seed yield indicated that the plant height and number of capsules/plant were highly and positively correlated with seed yield under both WW and WS conditions. The principal component analysis (PCA) revealed that among the traits studied, number of capsules/ plant, total dry matter, stomatal conductance, transpiration rate and fatty acid i.e ., palmitic acid were the most important traits that accounted for more than half of the total variation among the sesame genotypes studied. Furthermore, the scatter plot revealed that two genotypes, IC 132,207 and IC 205,471 were stable performers under both stress and irrigated conditions, whereas the performance of check GT-10 varied depending upon conditions.

Research paper thumbnail of Conserved Water Use and Temperature Modulation in the Canopy Confer Adaptation to Residual Moisture Stress in Safflower

Research paper thumbnail of Leaf potassium status for drought tolerance: The hunt for promising sesame (Sesamum indicum L.) accessions

Journal of Plant Nutrition, 2022

Research paper thumbnail of Role of heterosis for photosynthetic traits and sink organs in seed yield enhancement in safflower

Israel Journal of Plant Sciences

Genetic basis of heterosis has been exploited for yield improvement in safflower (Carthamus tinct... more Genetic basis of heterosis has been exploited for yield improvement in safflower (Carthamus tinctorius L.) but little is known about physiological basis of heterosis for yield. The objective of this study was to quantify the physiological basis of heterosis for seed yield in safflower by examining 19 safflower hybrids and their parents for photosynthetic traits, and yield and its components. The results showed that heterosis for yield and its components was high and positive but was low and negative for photosynthetic traits in most of the hybrids studied. There were weak and non-significant relations between photosynthetic traits and yield and its components. Hybrids were more efficient in translocating photoassimilates to two major sink organs viz., number of seeds and number of capitula despite having low net photosynthesis than parents. Seed yield increase in safflower is more sink-than source-limited and was necessary through heterosis for sink organs. Heterosis breeding for la...

Research paper thumbnail of The Indian Society of Oilseeds Research

A study was carried out to identify genotypes possessing fresh seed dormancy in Spanish bunch gen... more A study was carried out to identify genotypes possessing fresh seed dormancy in Spanish bunch genetic background. Analysis of variance revealed highly significant differences among the genotypes for fresh seed dormancy at all the stages. Among the three parameters of fresh seed dormancy, only intensity of fresh seed dormancy at weekly interval instead of only at 7 days after sowing was found very important parameter to identify ideal sources of fresh seed dormancy in Spanish types. Two years results revealed that seven genotypes viz., PBS-12190, PBS-12191, PBS-12192, PBS-12171, PBS-12187, PBS-12189 and TPG-41 were the best genotypes which recorded average more than 90 per cent intensity of fresh seed dormancy for 21 days and these also had 100 per cent fresh seed dormancy at 7 DAS except PBS-12191, PBS-12171 and PBS-12189. However three genotypes PBS-12200, PBS-12200B and PBS-12201 also had more than 90 per cent fresh seed dormancy for 14 days. Therefore, these genotypes were identi...

Research paper thumbnail of Role of Plant Based Edible Oils for Human Diet

AgroScience Today, Apr 30, 2021

Research paper thumbnail of Save Water Earn Money: A Campaign that Turns Lives of Thousand Farmers

Biotica Research Today, Mar 24, 2021

Research paper thumbnail of Save Water Earn Money: A Campaign that Turns Lives of Thousand Farmers

Biotica Research Today, Mar 24, 2021

Research paper thumbnail of Sesame Sesamum Indicum in the Rice Fallow Environment a Critical Appraisal

Not Available, Dec 31, 2019

Research paper thumbnail of Leaf potassium status for drought tolerance: The hunt for promising sesame (Sesamum indicum L.) accessions

Journal of Plant Nutrition, 2022

Research paper thumbnail of Can plant bio-regulators minimize crop productivity losses caused by drought, heat and salinity stress? An integrated review

Journal of applied botany and food quality, 2016

Plant bio-regulators (PBRs), are biochemical compounds which stimulate plant growth and productiv... more Plant bio-regulators (PBRs), are biochemical compounds which stimulate plant growth and productivity when applied, even in small quantities at appropriate plant growth stages. These are being extensively used in agriculture to enhance the productivity particularly in horticultural crops but are not as prevalent in field crops. Their central role in plant growth and development is through nutrient allocation and source-sink transitions while some of the PBRs stimulate hormones related to abiotic stress tolerance. Since climate change and degrading natural resources are projected to amplify the stresses, particularly soil moisture deficit, high temperature and soil salinity, PBRs are likely to play a crucial role in plant growth regulation. However, the utility of PBRs to enhance crop productivity under stresses induced by abiotic factors needs critical evaluation. Research efforts so far have centered on the crop and agro-ecosystem specificity, optimal doses and schedule of their app...

Research paper thumbnail of Identifying Traits Associated With Terminal Drought Tolerance in Sesame (Sesamum indicum L.) Genotypes

Frontiers in Plant Science, 2021

Sesame is predominantly cultivated in rainfed and low fertile lands and is frequently exposed to ... more Sesame is predominantly cultivated in rainfed and low fertile lands and is frequently exposed to terminal drought. Sesamum species inhabiting dryland ecosystems adaptively diverge from those inhabiting rainfed habitats, and drought-specific traits have a genetic basis. In sesame, traits associated with drought conditions have not been explored to date, yet studies of these traits are needed given that drought is predicted to become more frequent and severe in many parts of the world because of climate change. Here, 76 accessions from the available Indian core set were used to quantify variation in several traits under irrigated (WW) and terminal drought stress (WS) conditions as well as their association with seed yield over two consecutive years. The range of trait variation among the studied genotypes under WW and WS was significant. Furthermore, the traits associated with seed yield under WW and WS differed. The per se performance of the accessions indicated that the expression o...

Research paper thumbnail of Source and sink traits and their relationship under deficit soil moisture stress conditions in an indeterminate crop: sesame (Sesamum indicum L.)

Research paper thumbnail of Influence of sowing environments on yield of sesame genotypes under shifting weather conditions of Deccan Plateau (Telangana)

Journal of Oilseeds Research

Climate change poses a challenge to sustainability of agricultural ecosystems and in turn the soc... more Climate change poses a challenge to sustainability of agricultural ecosystems and in turn the social and economic development, livelihoods of communities in the world and India is no exception. Sesame is an important oilseed crop that has nutritional components such as lignans (antioxidant), sesamol along with tocopherols. This crop is grown under varied climatic conditions in the country even though it is highly sensitive to thermal regimes. Therefore, identifying or breeding sesame varieties with adaptation to wider ecological regions with high yield potential is the need of the hour. To identify high yielding sesame genotypes under shifting weather conditions of Deccan Plateau, an experiment was conducted with different dates of sowing. The sowing dates were designed in such a way that itconsidered the present cropping situation where it is grown after the harvest of the kharif crop. A set of popular farmer preferred sesame varieties that are generally grown in different sesame g...

Research paper thumbnail of Role of Plant Based Edible Oils for Human Diet

In India there are seven edible oil seed crops, namely groundnut, rapeseed & mustard, soybean, su... more In India there are seven edible oil seed crops, namely groundnut, rapeseed & mustard, soybean, sunflower, sesame, safflower and niger, blessed by the benefit of the diverse agro-climatic areas. Oilseeds are important segment of tropical agriculture as they provide access to nutrition through protein and oil to humans and livestock. Edible oils are crucial for human nutrition, as they are energy dense with a high fat content. Human body needs some of the vital acids like Poly Unsaturated Fatty Acids (PUFA), which are not synthesized by the human body on its own, which obligates us to take from external sources. As vegetable oils are excellent source for PUFA, Mono-unsaturated fatty acids, Vitamins and others, an attempt was made to highlight the core health benefits of major vegetable oils.

Research paper thumbnail of Analysing the SPAD dynamics of water-stressed vs. well-watered sesame (<i>Sesamum indicum</i> L.) accessions and establishing their relationship with seed yield

PeerJ, Jan 18, 2023

Background. The chlorophyll content is susceptible to deficit moisture stress and may affect the ... more Background. The chlorophyll content is susceptible to deficit moisture stress and may affect the plant yield. Leaf chlorophyll content is directly related to tolerance and higher productivity under deficit moisture stress (WS). The SPAD meter is an excellent tool for rapid analysis of crop chlorophyll content. Therefore, establishing a relationship between leaf chlorophyll content and seed yield is crucial in sesame, particularly under deficit moisture stress. Methods. Seeds of 37 sesame genotypes with checks were used in this study. These genotypes were mostly landraces, adapted to different agro-ecological zones in India. The selected genotypes were evaluated under well water (WW) and deficit moisture stress (WS) conditions. The SPAD readings were recorded ten (10) times each at every seven days intervals from the juvenile/first bud (30-35 days after sowing) to ripening/ physiological maturity (95-100 days after sowing) stage. This study aimed to identify the association between leaf SPAD readings (recorded at 7-days interval) and seed yield of sesame genotypes. Results. The analysis of variance revealed the presence of significant variation in SPAD readings due to treatment (WW and WS), genotypes, and their interaction effects. The SPAD readings at all stages were positively correlated with seed yield in both WW and WS. High values of correlation coefficients were observed at 52 (r: 0.672) and 59 (r: 0.655) DAS under WS; whereas at 59 (r: 0.960), 66 (r: 0.972) and 73 (r: 0.974) DAS under WW at one percent significance level (p < 0.01), which coincided with the mid-bloom stage of the sesame crop. The best-fit multiple regression model revealed that the dependence of sesame seed yield is significantly influenced by SPAD reading at 52 DAS under WS and 59 to 73 DAS under WW. Both these models provide a good fit with the chi-squared test, which compares the predicted and observed yield.

Research paper thumbnail of Source and sink traits and their relationship under deficit soil moisture stress conditions in an indeterminate crop: sesame (<i>Sesamum indicum</i> L.)

Plant Production Science, Apr 23, 2023

Research paper thumbnail of Physiological traits and indices to identify tolerant genotypes in sesame (Sesamum indicum L.) under deficit soil moisture condition

Research paper thumbnail of Morphophysiological responses and tolerance mechanisms of Xanthium strumarium to manganese stress

Ecotoxicology and environmental safety, Jan 15, 2018

Effective phytoremediation of manganese (Mn) requires the careful selection of a species that has... more Effective phytoremediation of manganese (Mn) requires the careful selection of a species that has a relatively high manganese tolerance. Exploring the physiological mechanisms related to Mn stress responses is crucial for identifying and employing species for Mn phytoremediation. Xanthium strumarium is a species that can accumulate high levels of Mn, thus it is a candidate species for Mn-phytoremediation. To reveal the tolerance mechanisms of this species to manage Mn stress, the morphological, physiological, and biochemical responses of seedlings grown in water cultures under six different Mn concentrations were analyzed. The results showed that X. strumarium can accumulate high levels of Mn, even as plant growth was inhibited by rising Mn concentrations. Malondialdehyde (MDA) content increased and catalase (CAT) activity decreased along with the increased Mn concentrations, while soluble protein and proline content, as well as the superoxide dismutase (SOD) and peroxidase (POD) en...

Research paper thumbnail of Analysing the SPAD dynamics of water-stressed vs. well-watered sesame (<i>Sesamum indicum</i> L.) accessions and establishing their relationship with seed yield

Research paper thumbnail of Morpho-physiological, quality traits and their association with seed yield in sesame (Sesamum indicum L.) indigenous collection under deficit moisture stress

Plant Physiology Reports, 2021

A field experiment was conducted to investigate the effect of deficit moisture stress on eleven s... more A field experiment was conducted to investigate the effect of deficit moisture stress on eleven sesame genotypes viz., IC-132171, IC-132186, IC-204445, IC-131500, IC-132207, IC-205471, IC-203962, IC-205353, IC-96229, and IC-204966 along with a national check (GT-10). The deficit moisture stress (WS) was imposed for a period of 50–55 days from flowering to physiological maturity. The morphological, physiological, and yield traits under WS significantly decreased in comparison with irrigated conditions (WW). Based on the mean trait performance studied among the genotypes, IC-204966 was found significantly superior with respect to plant height, capsules number, seed weight, total dry matter, leaf area, relative water content and reduced canopy temperature under WS conditions. The correlation analysis of different traits with seed yield indicated that the plant height and number of capsules/plant were highly and positively correlated with seed yield under both WW and WS conditions. The principal component analysis (PCA) revealed that among the traits studied, number of capsules/ plant, total dry matter, stomatal conductance, transpiration rate and fatty acid i.e ., palmitic acid were the most important traits that accounted for more than half of the total variation among the sesame genotypes studied. Furthermore, the scatter plot revealed that two genotypes, IC 132,207 and IC 205,471 were stable performers under both stress and irrigated conditions, whereas the performance of check GT-10 varied depending upon conditions.

Research paper thumbnail of Conserved Water Use and Temperature Modulation in the Canopy Confer Adaptation to Residual Moisture Stress in Safflower

Research paper thumbnail of Leaf potassium status for drought tolerance: The hunt for promising sesame (Sesamum indicum L.) accessions

Journal of Plant Nutrition, 2022

Research paper thumbnail of Role of heterosis for photosynthetic traits and sink organs in seed yield enhancement in safflower

Israel Journal of Plant Sciences

Genetic basis of heterosis has been exploited for yield improvement in safflower (Carthamus tinct... more Genetic basis of heterosis has been exploited for yield improvement in safflower (Carthamus tinctorius L.) but little is known about physiological basis of heterosis for yield. The objective of this study was to quantify the physiological basis of heterosis for seed yield in safflower by examining 19 safflower hybrids and their parents for photosynthetic traits, and yield and its components. The results showed that heterosis for yield and its components was high and positive but was low and negative for photosynthetic traits in most of the hybrids studied. There were weak and non-significant relations between photosynthetic traits and yield and its components. Hybrids were more efficient in translocating photoassimilates to two major sink organs viz., number of seeds and number of capitula despite having low net photosynthesis than parents. Seed yield increase in safflower is more sink-than source-limited and was necessary through heterosis for sink organs. Heterosis breeding for la...

Research paper thumbnail of The Indian Society of Oilseeds Research

A study was carried out to identify genotypes possessing fresh seed dormancy in Spanish bunch gen... more A study was carried out to identify genotypes possessing fresh seed dormancy in Spanish bunch genetic background. Analysis of variance revealed highly significant differences among the genotypes for fresh seed dormancy at all the stages. Among the three parameters of fresh seed dormancy, only intensity of fresh seed dormancy at weekly interval instead of only at 7 days after sowing was found very important parameter to identify ideal sources of fresh seed dormancy in Spanish types. Two years results revealed that seven genotypes viz., PBS-12190, PBS-12191, PBS-12192, PBS-12171, PBS-12187, PBS-12189 and TPG-41 were the best genotypes which recorded average more than 90 per cent intensity of fresh seed dormancy for 21 days and these also had 100 per cent fresh seed dormancy at 7 DAS except PBS-12191, PBS-12171 and PBS-12189. However three genotypes PBS-12200, PBS-12200B and PBS-12201 also had more than 90 per cent fresh seed dormancy for 14 days. Therefore, these genotypes were identi...

Research paper thumbnail of Role of Plant Based Edible Oils for Human Diet

AgroScience Today, Apr 30, 2021

Research paper thumbnail of Save Water Earn Money: A Campaign that Turns Lives of Thousand Farmers

Biotica Research Today, Mar 24, 2021

Research paper thumbnail of Save Water Earn Money: A Campaign that Turns Lives of Thousand Farmers

Biotica Research Today, Mar 24, 2021

Research paper thumbnail of Sesame Sesamum Indicum in the Rice Fallow Environment a Critical Appraisal

Not Available, Dec 31, 2019

Research paper thumbnail of Leaf potassium status for drought tolerance: The hunt for promising sesame (Sesamum indicum L.) accessions

Journal of Plant Nutrition, 2022

Research paper thumbnail of Can plant bio-regulators minimize crop productivity losses caused by drought, heat and salinity stress? An integrated review

Journal of applied botany and food quality, 2016

Plant bio-regulators (PBRs), are biochemical compounds which stimulate plant growth and productiv... more Plant bio-regulators (PBRs), are biochemical compounds which stimulate plant growth and productivity when applied, even in small quantities at appropriate plant growth stages. These are being extensively used in agriculture to enhance the productivity particularly in horticultural crops but are not as prevalent in field crops. Their central role in plant growth and development is through nutrient allocation and source-sink transitions while some of the PBRs stimulate hormones related to abiotic stress tolerance. Since climate change and degrading natural resources are projected to amplify the stresses, particularly soil moisture deficit, high temperature and soil salinity, PBRs are likely to play a crucial role in plant growth regulation. However, the utility of PBRs to enhance crop productivity under stresses induced by abiotic factors needs critical evaluation. Research efforts so far have centered on the crop and agro-ecosystem specificity, optimal doses and schedule of their app...

Research paper thumbnail of Identifying Traits Associated With Terminal Drought Tolerance in Sesame (Sesamum indicum L.) Genotypes

Frontiers in Plant Science, 2021

Sesame is predominantly cultivated in rainfed and low fertile lands and is frequently exposed to ... more Sesame is predominantly cultivated in rainfed and low fertile lands and is frequently exposed to terminal drought. Sesamum species inhabiting dryland ecosystems adaptively diverge from those inhabiting rainfed habitats, and drought-specific traits have a genetic basis. In sesame, traits associated with drought conditions have not been explored to date, yet studies of these traits are needed given that drought is predicted to become more frequent and severe in many parts of the world because of climate change. Here, 76 accessions from the available Indian core set were used to quantify variation in several traits under irrigated (WW) and terminal drought stress (WS) conditions as well as their association with seed yield over two consecutive years. The range of trait variation among the studied genotypes under WW and WS was significant. Furthermore, the traits associated with seed yield under WW and WS differed. The per se performance of the accessions indicated that the expression o...