Several countries in Africa, Latin America along with China have incorporated QPM in their Agricultural development plan. A new quality protein maize variety (QPM) was developed by breeders and farmers using the parti...Several countries in Africa, Latin America along with China have incorporated QPM in their Agricultural development plan. A new quality protein maize variety (QPM) was developed by breeders and farmers using the participatory breeding approach in the DR-Congo. It is adapted to all the maize growing regions in the country. Inbred lines from this new variety were produced for further development of maize synthetic populations. The main objective of the present study is to determine the level of amino acid changes in early generations of inbred lines. The results of the study revealed a significant decrease of 33% and 38% of tryptophan in S1 and S2 inbred lines compared to the original parental MUDISHI 3 population, respectively. There was a decrease of 15% of lysine in S2 inbred lines compared to the parental MUDISHI 3. Actually, S2 inbred lines of MUDISHI 3 contain similar level of lysine compared to the genetically improved normal maize (Salongo 2) that is currently released. The development of composite lines is recommended over synthetic populations to maintain the high levels of lysine and tryptophan along with other desirable agronomic characteristics since they involve the intercrossing of open pollinated varieties.展开更多
Quality protein maize(QPM)(Zea mays L.) varieties contain enhanced levels of tryptophan and lysine, exhibiting improved nutritive value for humans and livestock. However, breeding QPM varieties remains challenging due...Quality protein maize(QPM)(Zea mays L.) varieties contain enhanced levels of tryptophan and lysine, exhibiting improved nutritive value for humans and livestock. However, breeding QPM varieties remains challenging due to the complex process of rebalancing storage protein. This study conducted transcriptome and proteome analyses to investigate the process of storage proteins rebalancing in opaque2(o2) and QPM. We found a weak correlation between the transcriptome and proteome, suggesting a significant modulating effect of post-transcriptional events on non-zein protein abundances in Mo17o2 and QPM. These results highlight the advantages of proteomics. Compared with Mo17, 672 differentially expressed proteins(DEPs) were identified both in Mo17o2 and QPM, and several of them were associated with storage protein, starch, and amino acid synthesis. We identified 178 non-zeins as DEPs in Mo17o2 and QPM kernels. The up-regulated non-zein DEPs were enriched in lysine, tryptophan, and methionine, which affected the protein quality. Co-expression network analysis identified regulators of storage protein synthesis in QPM, including O2,PBF1, and several transcription factors. Our results revealed how storage protein rebalancing occurs and identified nonzein DEPs that may facilitate superior-quality QPM breeding.展开更多
Logistic and exponential approaches have been used to simulate plant growth and leaf area index (LAI) in different growing conditions. The objective of the present study was to develop and evaluate an approach to simu...Logistic and exponential approaches have been used to simulate plant growth and leaf area index (LAI) in different growing conditions. The objective of the present study was to develop and evaluate an approach to simulate maize LAI that expresses key physiological and phonological processes using a minimum entry requirement for Quality Protein maize (QPM) varieties grown in the southwestern region of the DR-Congo. Data for the development and testing of the model were collected manually in experimental plots using a non-destructive method. Simulation results revealed measurable variations between crop seasons (long season A and short season B) and between the two varieties (Mudishi-1 and Mudishi-3) for height, number of visible leaves, and LAI. For both seasons, Mudishi-3, a short stature variety was associated with expected stable yield based on simulation data. In general, the model simulated reliably all the parameters including the LAI. The LAI value for mudishi-1 was higher than that of Mudishi-3. There were significant differences among the model parameters (K, Ti, a, b, Tf) and between the two varieties. In all crop conditions studied and for the two varieties, the senescence rate (a) was higher, while the growth rate (b) was lower compared to the estimates based on the STICS model.展开更多
Waxy maize with its pure amylopectin starch is the staple food of many ethnic minorities in hilly regions of Southeast Asia （SEA）. A combination of waxy and quality protein maize （QPM） traits would improve the qua...Waxy maize with its pure amylopectin starch is the staple food of many ethnic minorities in hilly regions of Southeast Asia （SEA）. A combination of waxy and quality protein maize （QPM） traits would improve the quality of protein of waxy maize for human consumption. Double recessive waxy-QPM （wx-o2） genotypes had been generated from Southern Chinese material by haploid induction of crosses heterozygous for the two quality traits with an absolutely conserved waxy type and an improved amino acid profile. The vitreous kernel trait （due to the additional modifier genes present in QPM） was lost in the wx-o2 plant material; this may be due to the waxy mutation, this is anyhow desirable for acceptance as waxy maize is preferred due to its soft grains. The content of the quality limiting amino acid lysine was greatly increased in double recessive wx-o2 genotypes compared to standard waxy maize, but still with a high variation among genotypes for future improvement. Conclusively, it was indeed possible to combine two grain quality mutations successfully within one genotype and prototypes of double quality wx-o2 are available now to contribute to meet human requirements in essential amino acids and thus reduce malnutrition in various regions of Asia.展开更多
Maize production in tropical Africa is often negatively affected by drought. The main objectives of the present study were to 1) analyze the impact of water stress on the agro-morphological performance of two varietie...Maize production in tropical Africa is often negatively affected by drought. The main objectives of the present study were to 1) analyze the impact of water stress on the agro-morphological performance of two varieties of Quality Protein Maize (QPM) compared to two normal maize varieties and 2) assess their adaptive response in contrasting water environments. Agro-morphological responses to water deficiency of maize (Zea mays L.) were assessed in controlled experiments using four maize varieties, two normal maize (Zm725 and Mus1) and two quality protein maize (Mudishi1 and Mudishi3) varieties. They were subjected to three water regimes (100%, 60%, 30% water retention capacity) at the beginning of the bloom stage, using a Fischer block design with four replications. Significant differences (p < 0.05) among varieties, water regimes and their interactions for plant growth and production parameters were observed. Reduction of water supply to plants caused changes in aerial and underground plant growth. Plant stem height, foliar expansion, and root system development characterizing vegetative growth showed variation in varietal response to water regimes. Mus1 (normal maize variety) was the best adapted to variations in water regimes because they developed an important root volume to adapt to the effects of water deficit while maintaining their morphological and productive characteristics.展开更多
Maize research at Institute for Agricultural Research, Samaru, Nigeria resulted in sustained growth in yields in the last two decades. Maize is grown throughout the country with guinea savanna as the most important ma...Maize research at Institute for Agricultural Research, Samaru, Nigeria resulted in sustained growth in yields in the last two decades. Maize is grown throughout the country with guinea savanna as the most important maize growing zone. In the last five years, four new open pollinating varieties developed in collaboration with the International Institute of Tropical Agriculture （IITA, Ibadan） had been released for production. Hybrid varieties are also marketed by seed companies. The research was focused on variety improvement, improved management practices, integrated pests and disease control, soil fertility management, on-farm testing of improved production packages and socio-economics of production as well as adoption studies. The recently released quality protein maize has improved the nutritional status of vulnerable groups. Drought tolerant maize for Africa research project has contributed to sustainable maize production, poverty reduction and food security in the continent.展开更多
Traditional complementary foods are mainly starchy foods with limiting nutrient quality and can be fortified using protein rich crops like almond seed.This research thus aimed at investigating the nutritional quality ...Traditional complementary foods are mainly starchy foods with limiting nutrient quality and can be fortified using protein rich crops like almond seed.This research thus aimed at investigating the nutritional quality of the formulated complementary diet from locally available almond seeds(Prunus amygdalus),high quality protein(QPM)and yellow maize after blending into flours.The proximate and amino acid compositions,in vitro protein qualities and functional properties of the blended flours were determined using standard methods.The in vivo studies involved feeding the weanling Wister albino rats with blended flours and commercial Cerelac(control),followed by hematological and histopathological determinations,while sensory attributes were evaluated by the semi-trained panelists.The protein contents of the flour blends(24–28%)were significantly(p<0.05)better with adequate indispensable amino acids and improved functionalities than commercial cerelac(23%).Comparatively,the dried germinated QPM(DGQPM)has significant(p<0.05)higher biological value(~37%)than fermented high QPM(FHQPM)(~30%),thereby indicating that the germination process improved protein quality of the diets.Besides,the in vivo data showed a positive effect of germination process as the rats fed with DGQPM has low white blood cells(30×10^(2))compared to FHQPM(42×10^(2))and cerelac(51×10^(2)).However,the fermentation process improved the packed cell volume of rats fed with FHQPM(49%)when compared to DGQPM and cerelac(47%).The formulated diets have no negative effects on the protein content(45.19–51.88 mg N/g)and weight(0.25–1.36 g)of the internal organs(liver,kidney and tissue)of the animals when compared to cerelac(53.72–55.04 mg N/g;0.25–1.98 g),respectively.The panelists generally accepted all the formulated diets,hence encouraging their utilization in the global preparation of complimentary foods for young children to meet their nutritional needs and adding value to the locally produced underutilized almond seeds.展开更多
文摘Several countries in Africa, Latin America along with China have incorporated QPM in their Agricultural development plan. A new quality protein maize variety (QPM) was developed by breeders and farmers using the participatory breeding approach in the DR-Congo. It is adapted to all the maize growing regions in the country. Inbred lines from this new variety were produced for further development of maize synthetic populations. The main objective of the present study is to determine the level of amino acid changes in early generations of inbred lines. The results of the study revealed a significant decrease of 33% and 38% of tryptophan in S1 and S2 inbred lines compared to the original parental MUDISHI 3 population, respectively. There was a decrease of 15% of lysine in S2 inbred lines compared to the parental MUDISHI 3. Actually, S2 inbred lines of MUDISHI 3 contain similar level of lysine compared to the genetically improved normal maize (Salongo 2) that is currently released. The development of composite lines is recommended over synthetic populations to maintain the high levels of lysine and tryptophan along with other desirable agronomic characteristics since they involve the intercrossing of open pollinated varieties.
基金supported by the National Natural Science Foundation of China (31971951 and 31771796)。
文摘Quality protein maize(QPM)(Zea mays L.) varieties contain enhanced levels of tryptophan and lysine, exhibiting improved nutritive value for humans and livestock. However, breeding QPM varieties remains challenging due to the complex process of rebalancing storage protein. This study conducted transcriptome and proteome analyses to investigate the process of storage proteins rebalancing in opaque2(o2) and QPM. We found a weak correlation between the transcriptome and proteome, suggesting a significant modulating effect of post-transcriptional events on non-zein protein abundances in Mo17o2 and QPM. These results highlight the advantages of proteomics. Compared with Mo17, 672 differentially expressed proteins(DEPs) were identified both in Mo17o2 and QPM, and several of them were associated with storage protein, starch, and amino acid synthesis. We identified 178 non-zeins as DEPs in Mo17o2 and QPM kernels. The up-regulated non-zein DEPs were enriched in lysine, tryptophan, and methionine, which affected the protein quality. Co-expression network analysis identified regulators of storage protein synthesis in QPM, including O2,PBF1, and several transcription factors. Our results revealed how storage protein rebalancing occurs and identified nonzein DEPs that may facilitate superior-quality QPM breeding.
文摘Logistic and exponential approaches have been used to simulate plant growth and leaf area index (LAI) in different growing conditions. The objective of the present study was to develop and evaluate an approach to simulate maize LAI that expresses key physiological and phonological processes using a minimum entry requirement for Quality Protein maize (QPM) varieties grown in the southwestern region of the DR-Congo. Data for the development and testing of the model were collected manually in experimental plots using a non-destructive method. Simulation results revealed measurable variations between crop seasons (long season A and short season B) and between the two varieties (Mudishi-1 and Mudishi-3) for height, number of visible leaves, and LAI. For both seasons, Mudishi-3, a short stature variety was associated with expected stable yield based on simulation data. In general, the model simulated reliably all the parameters including the LAI. The LAI value for mudishi-1 was higher than that of Mudishi-3. There were significant differences among the model parameters (K, Ti, a, b, Tf) and between the two varieties. In all crop conditions studied and for the two varieties, the senescence rate (a) was higher, while the growth rate (b) was lower compared to the estimates based on the STICS model.
文摘Waxy maize with its pure amylopectin starch is the staple food of many ethnic minorities in hilly regions of Southeast Asia （SEA）. A combination of waxy and quality protein maize （QPM） traits would improve the quality of protein of waxy maize for human consumption. Double recessive waxy-QPM （wx-o2） genotypes had been generated from Southern Chinese material by haploid induction of crosses heterozygous for the two quality traits with an absolutely conserved waxy type and an improved amino acid profile. The vitreous kernel trait （due to the additional modifier genes present in QPM） was lost in the wx-o2 plant material; this may be due to the waxy mutation, this is anyhow desirable for acceptance as waxy maize is preferred due to its soft grains. The content of the quality limiting amino acid lysine was greatly increased in double recessive wx-o2 genotypes compared to standard waxy maize, but still with a high variation among genotypes for future improvement. Conclusively, it was indeed possible to combine two grain quality mutations successfully within one genotype and prototypes of double quality wx-o2 are available now to contribute to meet human requirements in essential amino acids and thus reduce malnutrition in various regions of Asia.
文摘Maize production in tropical Africa is often negatively affected by drought. The main objectives of the present study were to 1) analyze the impact of water stress on the agro-morphological performance of two varieties of Quality Protein Maize (QPM) compared to two normal maize varieties and 2) assess their adaptive response in contrasting water environments. Agro-morphological responses to water deficiency of maize (Zea mays L.) were assessed in controlled experiments using four maize varieties, two normal maize (Zm725 and Mus1) and two quality protein maize (Mudishi1 and Mudishi3) varieties. They were subjected to three water regimes (100%, 60%, 30% water retention capacity) at the beginning of the bloom stage, using a Fischer block design with four replications. Significant differences (p < 0.05) among varieties, water regimes and their interactions for plant growth and production parameters were observed. Reduction of water supply to plants caused changes in aerial and underground plant growth. Plant stem height, foliar expansion, and root system development characterizing vegetative growth showed variation in varietal response to water regimes. Mus1 (normal maize variety) was the best adapted to variations in water regimes because they developed an important root volume to adapt to the effects of water deficit while maintaining their morphological and productive characteristics.
文摘Maize research at Institute for Agricultural Research, Samaru, Nigeria resulted in sustained growth in yields in the last two decades. Maize is grown throughout the country with guinea savanna as the most important maize growing zone. In the last five years, four new open pollinating varieties developed in collaboration with the International Institute of Tropical Agriculture （IITA, Ibadan） had been released for production. Hybrid varieties are also marketed by seed companies. The research was focused on variety improvement, improved management practices, integrated pests and disease control, soil fertility management, on-farm testing of improved production packages and socio-economics of production as well as adoption studies. The recently released quality protein maize has improved the nutritional status of vulnerable groups. Drought tolerant maize for Africa research project has contributed to sustainable maize production, poverty reduction and food security in the continent.
文摘Traditional complementary foods are mainly starchy foods with limiting nutrient quality and can be fortified using protein rich crops like almond seed.This research thus aimed at investigating the nutritional quality of the formulated complementary diet from locally available almond seeds(Prunus amygdalus),high quality protein(QPM)and yellow maize after blending into flours.The proximate and amino acid compositions,in vitro protein qualities and functional properties of the blended flours were determined using standard methods.The in vivo studies involved feeding the weanling Wister albino rats with blended flours and commercial Cerelac(control),followed by hematological and histopathological determinations,while sensory attributes were evaluated by the semi-trained panelists.The protein contents of the flour blends(24–28%)were significantly(p<0.05)better with adequate indispensable amino acids and improved functionalities than commercial cerelac(23%).Comparatively,the dried germinated QPM(DGQPM)has significant(p<0.05)higher biological value(~37%)than fermented high QPM(FHQPM)(~30%),thereby indicating that the germination process improved protein quality of the diets.Besides,the in vivo data showed a positive effect of germination process as the rats fed with DGQPM has low white blood cells(30×10^(2))compared to FHQPM(42×10^(2))and cerelac(51×10^(2)).However,the fermentation process improved the packed cell volume of rats fed with FHQPM(49%)when compared to DGQPM and cerelac(47%).The formulated diets have no negative effects on the protein content(45.19–51.88 mg N/g)and weight(0.25–1.36 g)of the internal organs(liver,kidney and tissue)of the animals when compared to cerelac(53.72–55.04 mg N/g;0.25–1.98 g),respectively.The panelists generally accepted all the formulated diets,hence encouraging their utilization in the global preparation of complimentary foods for young children to meet their nutritional needs and adding value to the locally produced underutilized almond seeds.
