Biofortification of rice with improved grain zinc (Zn) content is the most sustainable and cost‐effective approach to address Zn malnutrition in Asia. Genomics‐assisted breeding using precise and consistent Zn quantitative trait loci (QTLs), genes, and haplotypes can fast‐track the development of Zn biofortified rice varieties. We conducted the meta‐analysis of 155 Zn QTLs reported from 26 different studies. Results revealed 57 meta‐QTLs with a significant reduction of 63.2% and 80% in the number and confidence interval of the Zn QTLs, respectively. Meta‐quantitative trait loci (MQTLs) regions were found to be enriched with diverse metal homeostasis genes; at least 11 MQTLs were colocated with 20 known major genes involved in the production of root exudates, metal uptake, transport, partitioning, and loading into grains in rice. These genes were differentially expressed in vegetative and reproductive tissues, and a complex web of interactions were observed among them. We identified superior haplotypes and their combinations for nine candidate genes (CGs), and the frequency and allelic effects of superior haplotypes varied in different subgroups. The precise MQTLs with high phenotypic variance, CGs, and superior haplotypes identified in our study are useful for an efficient Zn biofortification of rice and to ensure Zn as an essential component of all the future rice varieties through mainstreaming of Zn breeding.

G × E interaction is major cause of discrepancy in crop yield under different environments. International Rice Research Institute (IRRI) launched their fourth flagship project on Global Rice Array (GRA-IV) to identify climate resilient rice genotypes. The G x E interaction was studied in 'Antenna Panel' genotypes Of rice using AMMI model. The results indicated that main effects as well as interactive G x E effects were significant for most of the traits. Major portion of the G x E was contributed by the genotypes. AMMI model having two principle components axis was found as the best predictive model. On the basis of biplots and ASV score SAHEL 177 for days to 50% flowering, SADRI for plant height; FEDEARROZ 50 for panicle length; CT11891-2-2-7-M for number of grains panicle -1 and SAHEL 108 for grain yield were considered as most stable genotypes in all the consecutive three environments. Moreover Yield Stability Index (YSI) supported the results that SAHEL 108 is the most superior genotype for grain yield over all the three environments of testing. Findings from this study are expected to help breeders to select suitable genotype on the basis of its performance and stability over locations. which can provide a head start to the rice improvement programmes for Indo-gangetic Plains and Hilly Tarai regions of India.

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