Fostering a culture of continuous improvement through regular monitoring of genetic trends in bre... more Fostering a culture of continuous improvement through regular monitoring of genetic trends in breeding pipelines is essential to improve efficiency and increase accountability. This is the first global study to estimate genetic trends across the International Maize and Wheat Improvement Center (CIMMYT) tropical maize breeding pipelines in eastern and southern Africa (ESA), South Asia, and Latin America over the past decade. Data from a total of 4152 advanced breeding trials and 34,813 entries, conducted at 1331 locations in 28 countries globally, were used for this study. Genetic trends for grain yield reached up to 138 kg ha−1 yr−1 in ESA, 118 kg ha−1 yr−1 South Asia and 143 kg ha−1 yr−1 in Latin America. Genetic trend was, in part, related to the extent of deployment of new breeding tools in each pipeline, strength of an extensive phenotyping network, and funding stability. Over the past decade, CIMMYT’s breeding pipelines have significantly evolved, incorporating new tools/techno...
Drought is one of the major abiotic constraints that adversely affect maize production in the rai... more Drought is one of the major abiotic constraints that adversely affect maize production in the rain-fed agro-environment in the Asian tropics. In view of the recurrent drought, stress-resilient (SR) maize hybrids were developed and deployed to minimize yield penalties and ensure minimum sustainable production of maize in mild to severe drought conditions. Data were collected from 180 farmers from two districts of northern Karnataka. Findings suggest that the household location, caste, access to credit, number of extension visits, and participation in field days significantly influence the adoption of the SR maize hybrid in the study area. The inverse probability weighting (IPW) estimator revealed that households adopting SR maize hybrid have higher yield and income (23% more yield and $137.86/ha more net income) than the non-adopters. As the SR maize hybrid has considerable scope for improving the livelihood and security of farmers, the agricultural policy should support and scale th...
In recent years, National Maize Research Program (NMRP) aimed a paradigm shift from open-pollinat... more In recent years, National Maize Research Program (NMRP) aimed a paradigm shift from open-pollinated varieties (OPVs) towards hybrid maize to achieve self-sufficiency in maize for food, feed, and hybrid seed within the country. In this mission, it is necessary to identify and deploy high-yielding stress-resilient maize hybrids that can cope with climate change effects, including heat stress. Under the project “Heat Tolerant Maize for Asia (HTMA)”, NMRP introduced the hybrids that performed better in previous years in different environments from International Maize and Wheat Improvement Center (CIMMYT) Hyderabad for multilocation on-farm testing. Fifteen genotypes were evaluated at two locations, two sites in Madi, Chitwan, and one in Ghorahi, Dang, along with Rampur Hybrid-8 as a heat-tolerant check, and RML-86/RML-96 and RML-95/RML-96 as normal checks. Randomized complete block design (RCBD) was used with three replicates during the spring of 2016/17. Likewise, another 20 and 18 pro...
Quality protein maize (QPM), with almost double lysine and tryptophan in protein, is no different... more Quality protein maize (QPM), with almost double lysine and tryptophan in protein, is no different from regular maize (RM) in terms of quantity of energy and protein. The objective of the study was to assess whether QPM can substitute RM as an efficient energy source as well as requirement of essential amino acids in poultry feed. Experiments were conducted to determine apparent metabolizable energy (AME), digestible amino acid values, and utilization pattern of QPM and RM in chickens. AME of QPM was similar to RM. Lysine and threonine digestibilities were significantly (P≤0.05) higher in QPM than RM. Dietary replacement of RM by QPM at 50% or higher level significantly improved the body-weight gain. The overall feed conversion ratio (0–40 days) improved significantly in QPM compared to RM at 50% replacement level or higher. Abdominal fat content decreased by 40% and breast meat yield increased by 4.91% by dietary replacement of RM with QPM at 100% level. The protein concentration in serum increased linearly by increasing the level of replacement of RM by QPM. Serum cholesterol decreased significantly in the dietary group where RM was replaced by QPM at 100% level. Neither dressed weight nor giblet weight was influenced by replacement of RM by QPM or supplementing lysine to RM-based diet. However, the breast weight increased and abdominal fat content decreased significantly where RM was replaced by QPM at 50% level or higher. Our findings clearly indicated that feeding value of QPM was higher than RM in broiler chickens.
An experiment was undertaken using open-top chambers to study the effect of CO2 enrichment on cro... more An experiment was undertaken using open-top chambers to study the effect of CO2 enrichment on crop growth and to assess the variation related to the time of CO2 exposure. In general, enriched CO2 conditions (600 ± 50 p.p.m.) in the chamber positively affected the growth and development of mungbean (Vigna radiata), a short-duration (60–65 days) summer pulse crop. However, there was significant variability in the effect of the crop stage/time of CO2 exposure. It was observed that high CO2 exposure at an early growth stage [0–20 days after germination (DAG)] had a larger effect than that at a later growth stage (21–40 DAG). The experiment also provided a means of assessing the short- and long-term effects of elevated CO2 on the carbon exchange rate at both stages of exposure. The study revealed that the sensitivity of plants to high CO2 was more pronounced with respect to net photosynthetic rate. The overall photosynthetic activity gave greater growth and development of plants under high CO2. Zusammenfassung Entwicklungsabhangige Empfindlichkeit von Mungbohne (Vigna radiata L. Wilczek) gegenuber erhohter Konzentration von Kohlendioxid Ein Experiment wurde in einer offenen Kammer unternommen, um den Einfluss von CO2-Anreicherung auf das Pflanzenwachstum zu untersuchen und die Variation in Bezug auf den Zeitpunkt der CO2-Behandlung zu bestimmen. Angereicherte CO2-Bedingung (600 ± 50 p.p.m) in der Kammer beeinfluste grundsatzlich positiv das Wachstum und die Entwicklung von Mungbohnen, einer Sommerhulsenfrucht mit kurzer Vegetationsdauer (60–65 Tage). Es zeigte sich allerdings eine signifikante Variabilitat gegenuber der Entwicklungsphase der Pflanzen im Hinblick auf die CO2-Behandlung. Es wurde beobachtet, dass hohe CO2-Behandlung im fruhen Wachstumsstadium (0–20 DAG) eine verstarkte Wirkung im Vergleich zu spateren Wachstumsstadien (21–40 DAG) aufwies. Ferner zeigte das Experiment auch Moglichkeiten, kurze und lange Auswirkungen einer erhohten CO2-Konzentration auf die Kohlenstoffaustauschrate (CER) in beiden Entwicklungsstadien nachzuweisen. Die Untersuchung zeigt, dass die Empfindlichkeit der Pflanzen gegenuber hoher CO2-Konzentration im Hinblick auf die Nettophotosyntheserate starker ausgepragt war. Die gesamte photosynthetische Aktivitat fuhrte zu einem starkeren Wachstum und der Entwicklung von Pflanzen unter hoher CO2-Konzentration.
High atmospheric temperatures can reduce maize production in different parts of Asia. Heat stress... more High atmospheric temperatures can reduce maize production in different parts of Asia. Heat stress is the major driving force behind the need for varietal development that confers a heat tolerance trait (drought + heat tolerant) to maize hybrids. CIMMYT has developed heat-tolerant maize hybrids and deployed them in the market in collaboration with NARS partners. This study was conducted to estimate farmers’ willingness to pay for heat-tolerant maize hybrids in the Terai region of Nepal. A socioeconomic survey of 404 randomly selected maize-growing households was conducted to estimate farmers’ willingness to pay using the contingent valuation method. Given the economic importance of heat-tolerant maize hybrids in maize cultivation, the survey showed that the average WTP for heat-tolerant maize hybrids was 71% more than that for the current varieties in the market, including overall seed sources and subsidized seed. Without a subsidy, the farmers’ WTP price was at a 19% premium compare...
In recent years, National Maize Research Program (NMRP) aimed a paradigm shift from open-pollinat... more In recent years, National Maize Research Program (NMRP) aimed a paradigm shift from open-pollinated varieties (OPVs) towards hybrid maize to achieve self-sufficiency in maize for food, feed, and hybrid seed within the country. In this mission, it is necessary to identify and deploy high-yielding stress-resilient maize hybrids that can cope with climate change effects, including heat stress. Under the project “Heat Tolerant Maize for Asia (HTMA)”, NMRP introduced the hybrids that performed better in previous years in different environments from International Maize and Wheat Improvement Center (CIMMYT) Hyderabad for multilocation on-farm testing. Fifteen genotypes were evaluated at two locations, two sites in Madi, Chitwan, and one in Ghorahi, Dang, along with Rampur Hybrid-8 as a heat-tolerant check, and RML-86/RML-96 and RML-95/RML-96 as normal checks. Randomized complete block design (RCBD) was used with three replicates during the spring of 2016/17. Likewise, another 20 and 18 pro...
The present experiment was conducted to understand the effect of soil moisture status on the econ... more The present experiment was conducted to understand the effect of soil moisture status on the economic or standard heterosis in fifty maize hybrids for grain yield and flowering traits. The trials were planted at Agricultural Research Farm, Banaras Hindu University, Varanasi in alpha-lattice design with two replications. The analysis of variance revealed the significant differences for grain yield and flowering related traits such as days to 50% anthesis, days to 50% silking and anthesis-silking interval under all the moisture conditions including optimal, managed drought and managed waterlogging conditions. Significant amount of heterosis was observed over the selected check P3502 for all the traits under study; however, the magnitude and direction varied with traits and with soil moisture level. For days to 50% anthesis, hybrids ZH17192, VH112926, VH123021, ZH114250, ZH16929 and ZH16930 were showed significant negative heterosis under all the moisture conditions that explained ear...
Background: A large area of the maize production in Indo-Gangetic plains of India exposes alterna... more Background: A large area of the maize production in Indo-Gangetic plains of India exposes alternative and combination of prolonged drought spells and heavy rainfall situation due to uncertainty of monsoon patterns. In such context, breeding for maize hybrids with cross-tolerant to both low and excess soil moisture stresses remain the ultimate alternative. Methods: Evaluation of 75 maize hybrids planted at Banaras Hindu University, India during the subsequent Rabi and Kharif seasons of 2017 and 2018, respectively. The hybrids were evaluated for acquiring information on inter-trait associations among yield and yield-related traits under different soil moisture regimes. The trials were planted in alpha-lattice design and managed stress was imposed and data recorded. Result: As our investigation was the evident of weak correlations among the traits studied, genotype × trait (GT) biplots are not advisable to select/ discard the genotypes under moisture stress conditions. The goodness of ...
Additional file 7: Figure S2. Sequence variations in the promoter region of OsMYB21 between Xoo-r... more Additional file 7: Figure S2. Sequence variations in the promoter region of OsMYB21 between Xoo-resistant and Xoo-susceptible accessions.
Additional file 4: Table 3S. Bayesian Information Criterion (BIC) test according to Schwarz [63],... more Additional file 4: Table 3S. Bayesian Information Criterion (BIC) test according to Schwarz [63], for all traits evaluated using the first five components of the principal component analysis.
Fostering a culture of continuous improvement through regular monitoring of genetic trends in bre... more Fostering a culture of continuous improvement through regular monitoring of genetic trends in breeding pipelines is essential to improve efficiency and increase accountability. This is the first global study to estimate genetic trends across the International Maize and Wheat Improvement Center (CIMMYT) tropical maize breeding pipelines in eastern and southern Africa (ESA), South Asia, and Latin America over the past decade. Data from a total of 4152 advanced breeding trials and 34,813 entries, conducted at 1331 locations in 28 countries globally, were used for this study. Genetic trends for grain yield reached up to 138 kg ha−1 yr−1 in ESA, 118 kg ha−1 yr−1 South Asia and 143 kg ha−1 yr−1 in Latin America. Genetic trend was, in part, related to the extent of deployment of new breeding tools in each pipeline, strength of an extensive phenotyping network, and funding stability. Over the past decade, CIMMYT’s breeding pipelines have significantly evolved, incorporating new tools/techno...
Drought is one of the major abiotic constraints that adversely affect maize production in the rai... more Drought is one of the major abiotic constraints that adversely affect maize production in the rain-fed agro-environment in the Asian tropics. In view of the recurrent drought, stress-resilient (SR) maize hybrids were developed and deployed to minimize yield penalties and ensure minimum sustainable production of maize in mild to severe drought conditions. Data were collected from 180 farmers from two districts of northern Karnataka. Findings suggest that the household location, caste, access to credit, number of extension visits, and participation in field days significantly influence the adoption of the SR maize hybrid in the study area. The inverse probability weighting (IPW) estimator revealed that households adopting SR maize hybrid have higher yield and income (23% more yield and $137.86/ha more net income) than the non-adopters. As the SR maize hybrid has considerable scope for improving the livelihood and security of farmers, the agricultural policy should support and scale th...
In recent years, National Maize Research Program (NMRP) aimed a paradigm shift from open-pollinat... more In recent years, National Maize Research Program (NMRP) aimed a paradigm shift from open-pollinated varieties (OPVs) towards hybrid maize to achieve self-sufficiency in maize for food, feed, and hybrid seed within the country. In this mission, it is necessary to identify and deploy high-yielding stress-resilient maize hybrids that can cope with climate change effects, including heat stress. Under the project “Heat Tolerant Maize for Asia (HTMA)”, NMRP introduced the hybrids that performed better in previous years in different environments from International Maize and Wheat Improvement Center (CIMMYT) Hyderabad for multilocation on-farm testing. Fifteen genotypes were evaluated at two locations, two sites in Madi, Chitwan, and one in Ghorahi, Dang, along with Rampur Hybrid-8 as a heat-tolerant check, and RML-86/RML-96 and RML-95/RML-96 as normal checks. Randomized complete block design (RCBD) was used with three replicates during the spring of 2016/17. Likewise, another 20 and 18 pro...
Quality protein maize (QPM), with almost double lysine and tryptophan in protein, is no different... more Quality protein maize (QPM), with almost double lysine and tryptophan in protein, is no different from regular maize (RM) in terms of quantity of energy and protein. The objective of the study was to assess whether QPM can substitute RM as an efficient energy source as well as requirement of essential amino acids in poultry feed. Experiments were conducted to determine apparent metabolizable energy (AME), digestible amino acid values, and utilization pattern of QPM and RM in chickens. AME of QPM was similar to RM. Lysine and threonine digestibilities were significantly (P≤0.05) higher in QPM than RM. Dietary replacement of RM by QPM at 50% or higher level significantly improved the body-weight gain. The overall feed conversion ratio (0–40 days) improved significantly in QPM compared to RM at 50% replacement level or higher. Abdominal fat content decreased by 40% and breast meat yield increased by 4.91% by dietary replacement of RM with QPM at 100% level. The protein concentration in serum increased linearly by increasing the level of replacement of RM by QPM. Serum cholesterol decreased significantly in the dietary group where RM was replaced by QPM at 100% level. Neither dressed weight nor giblet weight was influenced by replacement of RM by QPM or supplementing lysine to RM-based diet. However, the breast weight increased and abdominal fat content decreased significantly where RM was replaced by QPM at 50% level or higher. Our findings clearly indicated that feeding value of QPM was higher than RM in broiler chickens.
An experiment was undertaken using open-top chambers to study the effect of CO2 enrichment on cro... more An experiment was undertaken using open-top chambers to study the effect of CO2 enrichment on crop growth and to assess the variation related to the time of CO2 exposure. In general, enriched CO2 conditions (600 ± 50 p.p.m.) in the chamber positively affected the growth and development of mungbean (Vigna radiata), a short-duration (60–65 days) summer pulse crop. However, there was significant variability in the effect of the crop stage/time of CO2 exposure. It was observed that high CO2 exposure at an early growth stage [0–20 days after germination (DAG)] had a larger effect than that at a later growth stage (21–40 DAG). The experiment also provided a means of assessing the short- and long-term effects of elevated CO2 on the carbon exchange rate at both stages of exposure. The study revealed that the sensitivity of plants to high CO2 was more pronounced with respect to net photosynthetic rate. The overall photosynthetic activity gave greater growth and development of plants under high CO2. Zusammenfassung Entwicklungsabhangige Empfindlichkeit von Mungbohne (Vigna radiata L. Wilczek) gegenuber erhohter Konzentration von Kohlendioxid Ein Experiment wurde in einer offenen Kammer unternommen, um den Einfluss von CO2-Anreicherung auf das Pflanzenwachstum zu untersuchen und die Variation in Bezug auf den Zeitpunkt der CO2-Behandlung zu bestimmen. Angereicherte CO2-Bedingung (600 ± 50 p.p.m) in der Kammer beeinfluste grundsatzlich positiv das Wachstum und die Entwicklung von Mungbohnen, einer Sommerhulsenfrucht mit kurzer Vegetationsdauer (60–65 Tage). Es zeigte sich allerdings eine signifikante Variabilitat gegenuber der Entwicklungsphase der Pflanzen im Hinblick auf die CO2-Behandlung. Es wurde beobachtet, dass hohe CO2-Behandlung im fruhen Wachstumsstadium (0–20 DAG) eine verstarkte Wirkung im Vergleich zu spateren Wachstumsstadien (21–40 DAG) aufwies. Ferner zeigte das Experiment auch Moglichkeiten, kurze und lange Auswirkungen einer erhohten CO2-Konzentration auf die Kohlenstoffaustauschrate (CER) in beiden Entwicklungsstadien nachzuweisen. Die Untersuchung zeigt, dass die Empfindlichkeit der Pflanzen gegenuber hoher CO2-Konzentration im Hinblick auf die Nettophotosyntheserate starker ausgepragt war. Die gesamte photosynthetische Aktivitat fuhrte zu einem starkeren Wachstum und der Entwicklung von Pflanzen unter hoher CO2-Konzentration.
High atmospheric temperatures can reduce maize production in different parts of Asia. Heat stress... more High atmospheric temperatures can reduce maize production in different parts of Asia. Heat stress is the major driving force behind the need for varietal development that confers a heat tolerance trait (drought + heat tolerant) to maize hybrids. CIMMYT has developed heat-tolerant maize hybrids and deployed them in the market in collaboration with NARS partners. This study was conducted to estimate farmers’ willingness to pay for heat-tolerant maize hybrids in the Terai region of Nepal. A socioeconomic survey of 404 randomly selected maize-growing households was conducted to estimate farmers’ willingness to pay using the contingent valuation method. Given the economic importance of heat-tolerant maize hybrids in maize cultivation, the survey showed that the average WTP for heat-tolerant maize hybrids was 71% more than that for the current varieties in the market, including overall seed sources and subsidized seed. Without a subsidy, the farmers’ WTP price was at a 19% premium compare...
In recent years, National Maize Research Program (NMRP) aimed a paradigm shift from open-pollinat... more In recent years, National Maize Research Program (NMRP) aimed a paradigm shift from open-pollinated varieties (OPVs) towards hybrid maize to achieve self-sufficiency in maize for food, feed, and hybrid seed within the country. In this mission, it is necessary to identify and deploy high-yielding stress-resilient maize hybrids that can cope with climate change effects, including heat stress. Under the project “Heat Tolerant Maize for Asia (HTMA)”, NMRP introduced the hybrids that performed better in previous years in different environments from International Maize and Wheat Improvement Center (CIMMYT) Hyderabad for multilocation on-farm testing. Fifteen genotypes were evaluated at two locations, two sites in Madi, Chitwan, and one in Ghorahi, Dang, along with Rampur Hybrid-8 as a heat-tolerant check, and RML-86/RML-96 and RML-95/RML-96 as normal checks. Randomized complete block design (RCBD) was used with three replicates during the spring of 2016/17. Likewise, another 20 and 18 pro...
The present experiment was conducted to understand the effect of soil moisture status on the econ... more The present experiment was conducted to understand the effect of soil moisture status on the economic or standard heterosis in fifty maize hybrids for grain yield and flowering traits. The trials were planted at Agricultural Research Farm, Banaras Hindu University, Varanasi in alpha-lattice design with two replications. The analysis of variance revealed the significant differences for grain yield and flowering related traits such as days to 50% anthesis, days to 50% silking and anthesis-silking interval under all the moisture conditions including optimal, managed drought and managed waterlogging conditions. Significant amount of heterosis was observed over the selected check P3502 for all the traits under study; however, the magnitude and direction varied with traits and with soil moisture level. For days to 50% anthesis, hybrids ZH17192, VH112926, VH123021, ZH114250, ZH16929 and ZH16930 were showed significant negative heterosis under all the moisture conditions that explained ear...
Background: A large area of the maize production in Indo-Gangetic plains of India exposes alterna... more Background: A large area of the maize production in Indo-Gangetic plains of India exposes alternative and combination of prolonged drought spells and heavy rainfall situation due to uncertainty of monsoon patterns. In such context, breeding for maize hybrids with cross-tolerant to both low and excess soil moisture stresses remain the ultimate alternative. Methods: Evaluation of 75 maize hybrids planted at Banaras Hindu University, India during the subsequent Rabi and Kharif seasons of 2017 and 2018, respectively. The hybrids were evaluated for acquiring information on inter-trait associations among yield and yield-related traits under different soil moisture regimes. The trials were planted in alpha-lattice design and managed stress was imposed and data recorded. Result: As our investigation was the evident of weak correlations among the traits studied, genotype × trait (GT) biplots are not advisable to select/ discard the genotypes under moisture stress conditions. The goodness of ...
Additional file 7: Figure S2. Sequence variations in the promoter region of OsMYB21 between Xoo-r... more Additional file 7: Figure S2. Sequence variations in the promoter region of OsMYB21 between Xoo-resistant and Xoo-susceptible accessions.
Additional file 4: Table 3S. Bayesian Information Criterion (BIC) test according to Schwarz [63],... more Additional file 4: Table 3S. Bayesian Information Criterion (BIC) test according to Schwarz [63], for all traits evaluated using the first five components of the principal component analysis.
Uploads