Maize serves as a crucial nutrient reservoir for a significant portion of the global population. However, to effectively address the growing world population’s hidden hunger, it is essential to focus on two key aspects: biofortification of maize and improving its yield potential through advanced breeding techniques. Moreover, the coordination of multiple targets within a single breeding program poses a complex challenge. This study compiled mapping studies conducted over the past decade, identifying quantitative trait loci associated with grain quality and yield related traits in maize. Meta-QTL analysis of 2,974 QTLs for 169 component traits (associated with quality and yield related traits) revealed 68 MQTLs across different genetic backgrounds and environments. Most of these MQTLs were further validated using the data from genome-wide association studies (GWAS). Further, ten MQTLs, referred to as breeding-friendly MQTLs (BF-MQTLs), with a significant phenotypic variation explained over 10% and confidence interval less than 2 Mb, were shortlisted. BF-MQTLs were further used to identify potential candidate genes, including 59 genes encoding important proteins/products involved in essential metabolic pathways. Five BF-MQTLs associated with both quality and yield traits were also recommended to be utilized in future breeding programs. Synteny analysis with wheat and rice genomes revealed conserved regions across the genomes, indicating these hotspot regions as validated targets for developing biofortified, high-yielding maize varieties in future breeding programs. After validation, the identified candidate genes can also be utilized to effectively model the plant architecture and enhance desirable quality traits through various approaches such as marker-assisted breeding, genetic engineering, and genome editing.

The development of quality protein maize (QPM) was considered a significant leap toward improvement in the nutritional status of rural masses in developing countries. The nutritional quality of QPM is attributed to the higher concentration of essential amino acids, particularly lysine and tryptophan, in its kernel endosperm. However, the similarity in the grains of QPM and normal maize necessitates the development of a standard protocol to assess the protein quality of maize. The present study aimed at improving the protocol of protein quality assessment in QPM. For this purpose, endosperm defatting and protein estimation procedures were restandardized and optimized with respect to the protocol duration and its amenability for high-throughput analysis. Unlike normal maize, QPM and opaque-2 mutants were completely defatted within a 48 h period. It was observed that the tryptophan content, calculated at each defatting interval, increased in the samples defatted for a longer duration. No significant differences were observed in the tryptophan content analyzed in the samples defatted for 48 and 72 h. Moreover, the endosperm protein estimated by using the Bradford method with certain modifications strongly correlated with the micro-Kjeldahl method (r = 0.9). Relative to the micro-Kjeldahl method, the Bradford method was found to be precise, rapid, and hazard-free. The present findings enable a testing protocol of reduced time duration that can be used in resource-poor settings for the determination of a protein quality assay in QPM. Overall, the present study effectively helped in reducing the defatting time by 24 h and protein estimation by 3 h as compared to the already established International Maize and Wheat Improvement Center protocol. This is expected to enable the aggregation of high-protein-quality maize to facilitate its commercialization.

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Basmati rice cultivators with longer internodes and shallow rooting system are prone to lodging especially during panicle development thus ultimately reducing yield, quality as well as efficiency of mechanical harvesting.Manipulation of GA status both via using exogenous application of GA or use of GA biosynthesis inhibitors or either by genetic alteration are regularly used to optimize plant growth and yields. Keeping this in mind the main objective of the study was to assess the role of Prohexadione-calcium (Pro-Ca) to reduce internode elongation against lodging stress without negatively affecting its productivity. A field experiment was conducted on three cultivars of basmati rice (Punjab Basmati 2, Punjab Basmati 3 and Pusa Basmati 1121) in split plot design at three concentration levels (foliar application) of Pro-Ca @5,10 and 20mg/l at vegetative and anthesis stage. Pro-Ca was found to uphill the concentrations of total chlorophyll (~9%)and Carotenoid(~4%) content in leaves at both vegetative and anthesis stages. An increment in the photosynthetic rate in flag leaf was also recorded in Pro-Ca treated sets in comparison to control, A significant increase in sucrose content in fully expanded leaf at vegetative and flag leaf at anthesis stage was recorded.Plant height significantly decreased in Pro-Ca treated plants and this decrease in height was recorded more with increased concentration of Pro-Ca. The increase in the yield contributing parameters viz., number of spikes/plant and grain/m2might be attributed to the blockage of gibberellins synthesis on account of Pro-Ca applicationin selected basmati rice variety PUSA 1121 by upregulating the photosynthetic rate (2%) andalso increase in sucrose content(2 to 18%).