Timing of Transplantation vi-a-vis Growth and Yield of Aman Rice Varieties and Mutants

Abstract

The present study highlights the impact of transplanting dates on the development and productivity of Aman rice varieties and mutants in Mymensingh, Bangladesh. Aman rice, a critical crop in Bangladesh, plays a vital role in ensuring food security and supporting the livelihoods of millions. The most crucial alternative for adjusting a certain crop growth stage with particular climatic conditions which have a significant influence on the growth, development, and partitioning of dry matter is to change the date of sowing, transplanting or planting. A field experiment was conducted at BINA, HQ farm Mymensingh during the Aman season of 2022-2023 and 2023-24 to determine the optimum transplanting date (July 30 and August 20) for Aman rice mutants/variety namely BLB-P-019, BLB-P-318, BSB-24, MEF-10, MEF-27, MPQR-12, MPQR-62, RM-Kas-80-C-1, RM-16-N-8-1, RM-16-N-10, BRRI dhan49 and BRRI dhan87. The objective of the study was to find out the optimum transplanting date for maximizing the yield of Aman rice mutants/varieties. During 2022-23, the grain and straw yield was highest in July 30 between two transplanting dates, among mutants RM-Kas-80-C-1 obtained highest grain and straw yield. Similarly highest grain yield (5.3 tha-1) was obtained by RM-Kas-80-C-1 transplanted at July 30 followed by RM-16-N-10-1 (5.2 tha-1) transplanted at July 30. Similarly, during 2023-24, the grain yield had significant differences among the transplanting dates, tillering capacity and number of filled grains were higher among the different mutants/varieties. The highest grain yield of 6.31 t ha-1 occurred with the July 30 transplanting date. Among the varieties, BRRI dhan87 produced the highest yield of t ha-1, followed by BLB-P-318 at 5.93 t ha-1. Notably, BRRI dhan87 achieved the maximum grain yield of 6.56 t ha-1 when transplanted on July 30, while BLB-P-318 yielded 6.34 t ha-1 on the same date. These findings suggest that transplanting on July 30 is optimal for maximizing the yield of Aman rice mutants and varieties in Mymensingh. To promote sustainable agriculture and food security, local farmers can benefit from understanding mutant and variety reactions to transplanting dates. The study highlights the benefits of following transplanting windows, laying the groundwork for future research and local farming applications.