Year: 2026
Type: article
Abstract: Background: Terminal heat stress threatens wheat (Triticum aestivum L.) productivity, particularly when high temperatures coincide with anthesis and grain filling. In the present study, we developed a holistic framework for identifying heat-resilient wheat cultivars under the agro-climatic conditions of Northeast India. Methods: Five cultivars (HD 2967, PBW 343, UP 2338, Sonalika, and HIM 304) were evaluated under timely- and late-sown conditions using a randomized block design with three replications. Phenological, physiological, biochemical, and yield traits were assessed, including grain-filling duration, grain yield, SPAD, Fv/Fm, canopy temperature depression (CTD), relative water content (RWC), membrane stability index (MSI), antioxidant activity, membrane stability index (MSI), malondialdehyde (MDA), and proline. and proline. The heat susceptibility index, stress tolerance index, and a composite hyperthermal durability index (HDI) were calculated. Results: Late sowing reduced grain-filling duration, physiological performance, and grain yield. Resilient cultivars maintained higher SPAD, Fv/Fm, CTD, RWC, and MSI values and lower MDA accumulation. Conclusion: Heat resilience was associated with the coordinated maintenance of photosynthesis, water status, membrane integrity, antioxidant defense, and grain filling. The HDI provides an integrated approach for screening heat-resilient wheat cultivars under the agro-climatic conditions of Northeast India
Institution: Manipur International University
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: hybrid
OpenAlex ID: W7220958882