GWAS-Heat-Stress-Gene-Expression-Reproductive-Traits-Oryza-sativa

Heat stress poses a significant challenge to rice (Oryza sativa L.) cultivation, particularly in the context of climate change. This study investigates the effects of heat stress on rice reproduction and seedling survival and growth in two rice subpopulations – Aus and Tropical Japonica, with single allelic variations on chromosomes 3 and 7. Variations on these loci on chromosomes 3 and 7 are associated with genes controlling seed shape and reproductive performance in rice, as seen from a previous experiment in our lab. Using controlled environment experiments, we investigated the combined response of these rice subpopulations and allelic variations in the two loci to heat stress. The results show that heat significantly affects biomass, seed weight, seeds per panicle, and flowering time. Our results also show that Aus rice subpopulations with the AA allele on chromosome 3 were more resilient to heat stress by producing more seeds per panicle compared to the rest of the rice samples tested. Also, Aus rice samples with the GG allele on chromosome 7 were more affected by heat indicated by their significantly reduced biomass and flowering time under heat stress.