Effect of planting geometry on yield and yield attributes of aromatic rice genotypes

To evaluate the effects of plant spacing on the growth and yield of aromatic rice varieties, a field experiment was carried out at the Agronomy Filed Laboratory, Bangladesh Agricultural University, Mymensingh, Bangladesh during aman season. Four plant spacings viz. 25cm x 25cm (S 1 ), 20cm x 20cm (S 2 ), 20cm x 15 cm (S 3 ) and 15 cm x 10cm (S 4 ) and four fine rice varieties viz. Basmoti 370 (V 1 ), BRRI dhan37 (V 2 ), BRRI dhan38 (V 3 ) and Kailijira (V 4 ) were used. As factorial arrangement the experiment was fitted in a randomized complete block design with three replications. All agronomic practices were applied as recommended for each cultivar. The result revealed that the BRRI dhan38 produced the highest 1000-grain weight (19.05g) as well as yield (3.62 t ha -1 ). Oppositely, the V 2 produced the maximum tillers hill -1 (11.7), effective tillers hill -1 (9.5) but the poorest 1000 grain weight (14.81g) compared to V 3 resulting in the second highest grain yield (3.30 t ha -1 ). The highest number of spikelets panicle -1 (175.0), grain panicle-1 (126.6) and sterile spikelets (48.6) but the lowest number of effective tillers hill -1 (7.4) and minimum 1000 grain weight (10.25g) were recorded at Kailijira (V4) resulting the lowest grain yield (2.27 t ha -1 ) at Kailijira. The results that the widest spacing S 1 produced the tallest plant stature (147.5cm), the highest number of tillers hill -1 (14.0), effective tillers hill -1 (11.0), total spikelets panicle -1 (124.2), filled grain panicle -1 (102.0) while the lowest number of sterile spikelets (22.4). In terms of m -2 basis, all the characteristics were lowered compared to the spacing of 20cm x 15 cm resulting in the lowest grain yield (2.66 t ha -1 ). The variety BRRI dhan38 at the spacing of 20cm x 15cm produced significantly the highest grain yield (4.27 t ha-1) and the second highest grain yield was (4.00 t ha-1) recorded in BRRI dhan37 with the same spacing.