Deployment of fine and coarse grain rice cultivars in time and space for increased productivity

To examine the impact of mixture ratio and temporal deployment of fine and coarse grain cultivars on rice productivity and profitability, two experiments were carried out at Bangladesh Agricultural University. In both investigations, two monsoon rice cultivars viz., Binadhan-13 (a tall, late-maturing, fine-grained) and Dhani Gold (a semi-dwarf, mid-maturing, coarse-grained) were utilized. In the 1st experiment, rice cultivars were planted in different mixture ratios viz., sole Binadhan-13, sole Dhani Gold, 1:1, 2:3, 3:2, 2:4 and 4:2 ratio of Binadhan-13 to Dhani Gold. The second study included the introducing time of Dhani Gold viz., seven days before or after or same day of Binadhan-13, sole Binadhan-13 and sole Dhani Gold. Three replications of the randomized complete block design were used for both trials. In the first experiment, both cultivars produced more when grown in mixtures as opposed to solitary cultures. Even though Dhani Gold's sole culture had the greatest yield, it was statistically equivalent to combined yields when Binadhan-13 and Dhani Gold were grown together in mixtures at 2:1, 3:1, or 4:1 ratios. The maximum net return and benefit cost ratio (BCR) were achieved when Binadhan-13 and Dhani Gold were planted in mixture following a 4:2 ratio as opposed to when Binadhan-13 was grown solely. In the second experiment, a sole cultivar generated less yield than cultivars that were transplanted on the same day, before, and after another cultivar. Cultivation of sole Binadhan-13 produced the lowest net return and minimum BCR (1.37), while the highest net return and BCR (1.81) was recorded when Dhani Gold was planted seven days before Binadhan-13 in mixture. A clear economic advantage of mixed culture with temporal deployment over the sole culture of either cultivar was evident. Therefore, transplanting Dhani Gold in a 1:1 ratio seven days before Binadhan-13 may be advised for greater output and economic return.