Growth and yield performances, pathogenicity, heat tolerance, antioxidant activity, and pungency level of anthracnose resistant and heat tolerant inbreed lines and their F1 hybrids of chili (Capsicum annuum L.)

•Chili (Capsicum spp.) is the most extensively produced annual herbaceous vegetable crop and widely used as for vegetables, flavor and color in food industries.•High temperature as well as phytopathogenic (Colletotrichum spp.) fungus influence the chili output and causes substantial damage to chili fruit at both the pre-harvest and post-harvest stages, resulting in lower fruit dry weight and decay chemical composition.•To identify anthracnose resistant, heat tolerant chili genotypes those have high yield potential and improved fruit qualities (pungency and antioxidant qualities).•In addition, the results of this study will add to the chili pepper database and help guide chili breeders in future breeding programmes. Chili pepper (Capsicum annuum L.) cultivation is hampered by biotic and abiotic stressors, with poor performance caused by high temperatures exceeding 42 °C and anthracnose infestation. Chemical constituents such as antioxidants, phenols, capsaicin, and dihydrocapsaicin have a relationship with biotic and abiotic tolerance or resistance. Experiment was conducted with anthracnose resistant (CP-36, DP-37, DP-57, AP-25 and BP-23), heat tolerant inbreed lines (Putra chili 1, Putra chili 4, Putra chili 7, Putra chili 9 and Putra chili 10) and their hybrids to find anthracnose-resistant, heat-tolerant chili genotypes with high yield and pungency levels. For this purposes, pathogens were injected into both unripe and ripe chili fruits to determine their pathogenicity. On the other hand, four-week-old seedling was raised for a heat tolerance test to determine the percentage of partial damage (%) and thermo-stability index of the cell membrane (%). The research also included morphological, yield and yield contributing, physiological, and biochemical assessment in order to identify superior chili hybrids. All growth, yield, and physiological traits showed excellent genetic progress and heritability, but correlation analysis showed a highly significant positive link between yield per plant, plant height, the total number of branches, and the number of fruits per plant. Lesion area of unripe fruits were varied from 0.00 (cm2) to 0.24 (cm2) and 0.00 (cm2) to 0.18 (cm2) for the pathogen, UPMC1191 (Colletotrichum fructicola) and UPMC1192 (Colletotrichum sojae), respectively and also indicated that differential resistant to anthracnose pathogen. In a heat tolerance test, all of the hybrids with the improved heat tolerant line performed better in terms of cell m