IMPROVEMENT OF GROWTH, YIELD AND YIELD ATTRIBUTES OF AROMATIC RICE BY THE EXOGENOUS APPLICATION OF ZINC

Abstract

The experiment was conducted at the Agronomy Research Field, Hajee Mohammad Danesh Science and Technology University in Dinajpur from July to December 2023 to assess the effect of different levels of zinc fertilizer at different growth stages on yield performance of aromatic rice cv. Tulsimala. The experiment consisted of two factors, namely factor-A consisted of four doses of zinc, viz. Zn1 (control), Zn2 (5 kg ha-1), Zn3 (10 kg ha-1), and Zn4 (15 kg ha-1), and factor-B consisted of three application times of zinc, such as T1 (application of zinc at the tillering stage at 25 DAT), T2 (application of zinc at the panicle stage at 50 DAT), and T3 (application of zinc at the dough stage at 75 DAT). The experiment was laid out in a randomized complete block design with 12 treatment combinations with three replications. The treatments were randomly distributed to the plots within a block. Each plot was fertilized with urea, TSP, MoP, and those doses were recommended by BRRI. During the study period, various growth, yield and yield contributing parameters were recorded, including plant height (cm), number of effective tillers hill-1, panicle length (cm), filled grains panicle-1, sterile grains panicle-1, 1000-grain weight (g), grain yield (t ha-1), straw yield (t ha-1), biological yield (t ha-1), and harvest index (%). The study result showed that Zn4 have the tallest plant (162.58 cm at harvest) in all cases while Zn3 produced the highest number of effective tillers hill-1 (18.34), longest panicle length (26.63 cm), the maximum filled grains panicle-1 (186.52), the 1000-grain weight (10.35 g), the highest grain yield (1.67 t ha-1), the biological yield (5.08 t ha-1), and the harvest index (32.78%). Moreover, the T2 treatment recorded the maximum plant height (162.59 cm at harvest), number of effective tillers hill-1 (17.92), longest panicle length (25.34 cm), top grain yield (1.63 t ha-1), biological yield (5.08 t ha 1 ), and harvest index (32.05%). Considering interactions, Zn4T2 combination gave the best result for plant height (142.13 and 172.26 cm respectively) whereas the Zn3T2 had the highest number of effective tillers hill-1 (19.80), the longest panicle length (27.37 cm), the most filled grains panicle-1 (196.18), the highest grain yield (1.90 t ha-1), the highest straw yield (4.45 t ha-1), the highest biological yield (5.34 t ha-1) and the highest harvest index (35.42%). The results indicate that the best-performing Tulsimala aromatic rice variety in Bangladesh would benefit economically from applying 10 kg ha-1 of zinc at the panicle initiation stage.