Exploring heterosis, dominance effect, and genetic control in Brinjal (Solanum melongena L.) landraces

Brinjal (Solanum melongena L.) is an important warm-season vegetable with immense antioxidant potential. The present study aims to identify superior high-yielding plants with round fruits and tolerance to bacterial wilt through heterosis breeding. This study evaluated 52 brinjal genotypes, including 48 local landraces collected from eastern India, emphasizing the state of Odisha and four released varieties. The selection process focused on variations in both quantitative and qualitative traits and examined genetic variability, heritability, and genetic advance for yield and yield-contributing traits. The Shannon-Wiener diversity index (H') had an overall mean value of 0.733, with significant variations observed in fruit length-to-breadth ratio, leaf blade color, fruit shape, and petiole color. The estimated h² BS for each tested attribute varied from 64.90 to 98.17%, showing that all traits were highly heritable. Based on multivariate analysis, nine parents with different genetic backgrounds were selected among 52 genotypes of diverse origins for breeding study. To ascertain the degree of heterosis, dominance reaction, combining ability and gene action for 12 quantitative features crossed in a diallel fashion without reciprocals to develop 36 F₁ hybrids. Average fruit weight (79.46%) had the highest degree of significant heterobeltiosis in the desired directions, followed by fruit yield per plant (71.61%), plant spread (58.07%), primary branches per plant (56.25%), and days to 1st flowering (-32.72%). No dominance to over-dominance effects was involved in the inheritance of fruit yield and yield-attributing traits. Four landraces (Selection from BBSR-192-1, BBSR-192-1, BBSR-08-2, and BBSR-195-3) were identified as promising general combiners for fruit yield and yield-attributing traits. Overall, based on per se performance, heterotic response as well as estimates of combining ability, the four important crosses namely, BBSR-08-2 X BBSR-192-1, Jammusahi Local X BBSR-192-1, BBSR-195-3 X BBSR-192-1and BBSR-10-26 X BBSR-192-1 were highly tolerance to bacterial wilt as well as yield and suitable for commercial exploitation as F₁ hybrid in Solanum melongena for eastern part of India.