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...
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...
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.
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...
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...
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...
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...
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...
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...
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.
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...
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...
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...
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...
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