Yield Performance and Heterosis Analysis of Single-Cross Maize (Zea mays L.) Hybrids under Subtropical Winter Environments of Nepal

Abstract

The present experiment was conducted at Bharatpur-15, Fulbari, Chitwan, Nepal, from 28 November 2017 to 8 May 2018 to evaluate the performance of 27 maize (Zea mays L.) hybrids, including pipeline hybrids and commercial checks, under subtropical winter conditions. The experiment was laid out in a randomized alpha-lattice design with three replications. Data were recorded on yield, yield components, and flowering traits, and analyzed using analysis of variance (ANOVA), followed by mean separation using LSD and Duncan’s Multiple Range Test (DMRT). The results revealed significant differences among genotypes for all studied traits, indicating substantial genetic variability. Grain yield ranged from 7.08 to 20.99 t ha⁻¹, with K1(A) × Y33 recording the highest yield, followed by K5(A) × Y33 and K2(A) × Y33. These hybrids also exhibited superior performance in biomass yield, harvest index, and kernel weight. Flowering traits, particularly anthesis–silking interval (ASI), showed significant variation, with lower ASI associated with better reproductive efficiency and higher grain yield. Heterosis analysis revealed strong positive heterosis for grain yield, with K1(A) × Y33 showing the highest mid-parent heterosis (80.12%), indicating the importance of non-additive gene action. The study identified K1(A) × Y33, K5(A) × Y33, and K2(A) × Y33 as promising hybrids with high yield potential and desirable agronomic traits. These hybrids can be recommended for further multilocation testing and potential commercialization. Overall, the findings highlight the effectiveness of heterosis breeding in improving maize productivity and provide valuable insights for future hybrid development programs in Nepal and similar agro-ecological regions.

Int. J. Appl. Sci. Biotechnol. Vol 14(2): 88-98.