Groundnut (Arachis hypogaea L.) genotypes were assessed for pod yield and physiological parameters under heat-stress and non-stress environments. The air temperatures under heat-stress environments were 35 °C and above during flowering, and below 35 °C in non-stress environments. Variability was significant for pod yield and physiological parameters among the genotypes under heat stress. A pod yield reduction of 1.5% to 43.2% was observed under heat-stress environments. However, in heat-tolerant genotypes, either stable or increased pod yield was recorded under high-temperature stress. GJG 31, ICGV 87846, ICGV 03057, ICGV 07038 and GG 20 showed an increase in pod yield by 9.0% to 47.0% at high temperatures, with a 0.65% to 3.6% increase in pod growth rate, while ICGV 06420, ICGV 87128, ICGV 97182, TCGS 1043 and ICGV 03042 are stable for pod yield and recorded a 0.25% to 3.1% increase in pod growth rate. Pod yield, hundred-seed weight, and pod growth rate under heat stress can be used as criteria for selection of heat stress tolerant-genotypes. Based on stress tolerance indices and pod yield performance, ICGVs 07246, 07012, 06039, 06040, 03042, 07038 and 06424 were identified as heat-tolerant genotypes.

Rust and late leaf spot (LLS) resistance sources involving Arachis batizocoi, A. duranensis, A. cardenasii and A. sps Manfredi‐5 were identified from field evaluation of interspecific derivatives (IDs) of groundnut in a disease nursery for two seasons. Although the sources displayed low levels of resistance compared to currently cultivated lines, they contribute allele diversity in groundnut breeding that has so far relied on alleles contributed from A. cardenasii for disease resistance. Multiple disease‐resistant and agronomically superior IDs, ICGVs 11379, 10121, 10179, 05097, 02411 and 00248 involving A. batizocoi, A. duranensis and A. cardenasii can be used in breeding for groundnut improvement. Genetic variability for resistance to rust and LLS, yield and nutritional quality traits was influenced by genotype, environment and genotype × environment interaction effects in individual and pooled analyses. In case of FAD (fatty acid desaturase)‐mutant alleles that govern high oleic trait, allele mining of IDs (110) showed that frequency of mutation in ahFAD2B is rare, whereas of ahFAD2A is common. High oleic lines were not detected among the IDs.

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Despite its industrial potential, productivity in castor remains constrained by genotype × environment interactions (GEI) which obscure the true genetic potential of hybrids across variable production ecologies. The present investigation sought to elucidate the magnitude and pattern of GEI and to identify stable, high-performing hybrids for yield and yield-contributing traits across diverse agro-climatic conditions of Telangana, India. Eight elite castor hybrids were evaluated across multi-environment trials using AMMI (Additive Main Effects and Multiplicative Interaction) and GGE (Genotype and Genotype × Environment) biplot models to dissect stability, adaptability and environmental representativeness. Highly significant GEI effects were detected for seed yield, days to 50% flowering, number of nodes and hundred-seed weight underscoring the differential response of genotypes across environments. The AMMI biplot effectively captured interaction patterns, identifying Palem (E1) location as the most representative and least interactive environment for yield performance. “Which-won-where” analysis of the GGE biplot delineated mega-environment groupings, with PCH-596 excelling under Tandur (E2) and Tornala (E3) locations while ICH-5 demonstrated superior adaptability to E1. Yield Stability Index (YSI) and GGE ranking analyses consistently recognized PCH-596 (G₂) and ICH-5 (G₆) as the most stable and high-yielding hybrids across the environments. The integration of AMMI and GGE biplot methodologies proved highly effective in unravelling complex GEI patterns, facilitating the identification of genotypes with broad and specific adaptability. Further, Multi-Trait Stability Index (MTSI) has proven ICH-1160 (G₃) as the most stable genotype across the environments. These findings provide a quantitative basis for environment-specific hybrid recommendations and contribute to accelerating genetic gains in castor breeding programs targeting enhanced productivity and resilience.