Combining ability of quality protein maize (Zea mays L.) inbred lines for agronomic, yield and quality traits in temperate hilly regions of Kashmir, India

The combining ability provides insightful information about the genetic mechanisms that govern the inheritance of traits and enables the identification of potential inbred lines ; and promising hybrid combinations for crop improvement. However, most studies on quality protein maize (QPM) have focused on nutritional aspects, and very few are focused on their combining ability. In addition, studies on the adaptation, hybrid performance and stability of QPM in temperate areas remain scarce.Therefore, the present study sought to examine the combining ability of eight QPM inbred lines (QPM13, QPM14, QPM20, QPM21, QPM49, QPM50, VQL1, and VQL17). These 8 lines were subjected to half-diallel mating. Consequently, 28 crosses obtained were further evaluated in the temperate region of Kashmir against one check and parents in the RCBD, with three replications in a single row.The results revealed significant variances for general combining ability (GCA) and specific combining ability (SCA) for most of the recorded agronomic, yield, and quality traits. The crosses QPM49 × VQL1, QPM 13 × QPM14, QPM21 × VQL17, QPM13 × QPM50 and QPM50 × VQL17 were found to perform best in terms of earliness in tasselling (-1.842), silking (-1.204), days to mature (-2.654), highest yield (12.875 g)and protein content (1.113%), respectively. These promising crosses can be viable material sources for future QPM variety development programs in temperate regions.