Significance of yield sustainability to develop climate smart wheat (Triticum aestivum) in India

To ensure food security in India, not only the wheat (Triticum aestivum L.) productivity but yield sustainability is also crucial especially when the production environments are quite diverse. An experiment was conducted to examined multi-environment wheat yield trial data of popular wheat cultivars in two agro-climatically diverse regions i.e. northwestern plains zone (NWPZ) and central zone (CZ) under timely-sown (TS) and late-sown (LS) conditions with an aim to differentiate yield and yield sustainability at the level of 4 production environment, 11 prominent locations and 7 crop years. Wheat productivity matched in both zones; yet the level of yield-sustainability was much less in warmer climate of CZ. Yield sustainability was poorest in late-sown wheat of CZ and the drop in sustainability index (SI) was realized in locations, years and genotypes. For grain yield; locations and location-year interaction mattered most in each production environments but the years were crucial only in NWPZ-TS. Results showed that yield sustainability of test sites can not be adjudged by its productivity alone. Location status was associated with the yield sustainability only in NWPZ. Substantial drop in sustainability could be noticed in some crop seasons of CZ but deviations in NWPZ were smaller. In test sites, the causative factors associated with yield-sustainability varied under different production environments. Genotype-year interaction was effective in each situation except CZ-LS where only the crop year variations were supreme. Variations in locations and genotypes mattered most in NWPZ-TS whereas the crop year deviations were impactful in NWPZ-LS and CZ-TS environments. Based on the results; prospect of improvisation and breeding strategy have been suggested to select suitable production sites and the genotypes.