Climate Resilience of Aromatic Rice Genotypes in Zambia: Genetic Potential and Multi-environment Performance

This study evaluated the performance of nine aromatic rice genotypes across three environments in Zambia, varying in rainfall, temperature, and rainfall distribution which are Namushekende, Longe and Mt Makulu testing sites. Rice production in Zambia faces challenges due to diverse and changing environmental conditions. Aromatic rice cultivation in Zambia is gaining attention for its economic potential, driven by the high market demand for its unique aroma and flavor, which is linked to the presence of 2-acetyl-1-pyrroline. Genotype-by-environment (GxE) interactions are a critical consideration in rice breeding, significantly influencing yield stability and a variety's adaptability across diverse agro-ecological zones. The experiments were carried out on three different sites with two sites in Western Province of Zambia. Nine aromatic rice genotypes were assessed for yield and yield component performance across the three sites. Data was collected on yield and yield component traits for rice as follows: plant height, days to flowering, days to maturity, number of tillers per hill, culm length, panicle length, number of filled grains per panicle, fertility ratio, 1000 seed weight, grain yield biomass yield and harvest index. Collected data was subjected to analysis of variance using the Jamovi data analysis software (version 2.3.28). Turkey tests were also done to determine the comparison among genotypes in the measured variables. The results showed significant genotype-by-environment interactions, with some genotypes exhibiting drought and heat tolerance, while others were more adapted to high rainfall conditions. Genotypes ZMORY-02, ZMORY-03, ZMORY-04 and ZMORY-05 demonstrated good adaptability to droughty conditions as shown by relatively superior performance at Longe which was characterized by reduced rainfall and high mean temperatures. ZMORY-02 and ZMORY-08 demonstrated good general adaptability, performing well across the three environments. The study highlights the importance of considering specific environmental conditions when selecting and recommending rice varieties for cultivation in Zambia. The findings provide valuable insights for rice breeders to develop high-yielding, adaptable, and environment-specific aromatic rice varieties for Zambia's agro ecological regions. Further research, including more extensive field trials and genetic analyses, is warranted to enhance our understanding of the underlying genetic mechanisms and to refine breeding strategies for improved rice productivity and stability.