Evaluation of Early Rice (Oryza sativa L.) Genotypes for Yield and Yield Components in Madhesh Province of Nepal

The research was laid out in a randomized complete block design (RCBD) with two replications and twenty-four genotypes (two check varieties Hardinath-1 and Hardinath-3) in College of Natural Resource Management, Bardibas, Mahottari, Nepal. Geographically, it is situated at an altitude of 26.9431097° North, longitude 85.8910975° East; approximetly 160 m asl. The transplanting distance between the rice plants was 20cmx20cm with plant plot size: 4.5 m² (3.0mx1.5m) and the spacing between two consecutive plots were maintained at 0.5 m. Key agronomic traits of growth, yield and yield components were recorded. Data was entered and tabulated using MS-Excel and analyzed using Gen-Stat ver. 2015. Mean separation was done by DMRT at 5 % level of significance. The results revealed that the highest yield (6.87 t/ha) was achieved by the genotype IR-18-A-2294, followed by IR-19-A-5000 (6.51 t/ha), NS-314 (6.24 t/ha), NS-278 (6.26 t/ha), Hardinath-3 (6.24 t/ha) and least by NS-232 (3.91 t/ha). Hardinath-1 (86.5 DAT) had early maturity followed by NS-201 (91 DAT), Hardinath-3 (94 DAT), IR-19-A-5000 (96 DAT), and IR-132084-B-1191-1-2-B-12 (96 DAT) whereas late maturity was observed in NS-313 (104 DAT) and yields were 5.24 t/ha, 5.14 t/ha, 6.24 t/ha, 6.51 t/ha, 4.87 t/ha, and 5.98 t/ha respectively. In terms of earliness and yield potential, IR-18-A-2294 and IR-19-A-5000 were found to be superior, indicating their potential for further advancement and recommendation in rice production systems and suggesting their usefulness for farmers in areas where early maturity along with high production is desirable to fit into multiple cropping systems or to avoid climatic risks such as terminal drought or flooding. These results provide valuable insights into the selection and development of rice varieties adapted to the specific agro-ecological conditions of Nepal.