GROWTH AND YIELD OF T. AMAN RICE AS AFFECTED BY GENOTYPES AND SUPPLEMENTAL IRRIGATION

Abstract

A field experiment was conducted at the experimental farm of Sher-e-Bangla Agricultural University (SAU), Sher-e-Bangla Nagar, Dhaka during the period from July to December 2018 to study the effect of supplemental irrigation on growth and yield of different Aman rice genotypes. The experiment comprised two factors; 1. irrigation having two levels (I 0 =

no supplemental irrigation (rainfed) and I 1 = supplemental irrigation) and 2. eight rice genotypes (G 1 = SAU AGDL1, G 2 SAU AGDL2, G3 = SAUAGDL3, G 4 = SAU AGDL12, G 5 = SAU AGDL13, G 6 SAU AGDL14, G 7 = SAU AGDL15 and G 8 =

Kataribhog (local)). The trial was setup in split plot design with irrigation in the main plot and genotypes in the sub-plot with three replications. Significant variation was recorded in terms of growth and different yield contributing characters and yield. The supplemental irrigated plots gave higher values over the non-irrigated plots in all the parameters except number of unfilled grains panicle -1 . At harvest, G 1 produced the tallest plant (199.23 cm), the highest leaf area index (3.36), the longest panicle (29.78 cm), the highest number of total grains panicle -1 (219.50), the highest weight of 1000-grains (28.95 g) and the highest grain yield (6.05 t ha -1 ). However, G 8 (Kataribhog) produced the highest number of tillers hill -1 (18.50), the highest number of effective tillers m (402.78), the lowest LAI (2.45), the shortest panicle (26.22 cm), lower number of primary branches panicle -1 (10.75), the lowest weight of 1000-grains (13.40 g), the lowest grain yield (5.18 t ha -1 ) and minimum harvest index (28.37%). At harvest, the tallest plant (201.47 cm), the highest number of filled grains panicle -1 (192.00), the highest number of total grains panicle -1 (228.67), the highest weight of 1000-grains (29.10 g) and the highest grain yield (6.44 t ha -1 ) was recorded from I 1 G 1 . On the contrary, the shortest plant (149.90 cm), the lowest number of tillers hill -1 (11.33), the lowest dry matter weight hill -1 (43.13 g), the lowest number of filled grains panicle (138.33), the lowest straw yield (10.78 t ha t ha -1 ) was recorded from I 0 G 4 -1 -2 ) and the lowest biological yield (16.02 . However, the lowest LAI (2.28), the shortest panicle (25.46 cm), the lowest number of primary branches panicle -1 (10.40), the highest number of unfilled grains panicle -1 (49.33), and the lowest weight of 1000-grains (13.29 g) was recorded in I 0 G 8 . The maximum harvest index (32.60%) was observed in I 0 G 4 , while the minimum (28.10%) from I 1 G 8 . However, the interaction treatments I 1 G 2 ,

I 1 G 6 and I 1 G 7 had grain yields (5.92 - 6.00 t ha -1 ) which were not significantly lower than that of I 1 G 1 .

Therefore, the genotypes SAU AGDL1, SAU AGDL2, SAU AGDL14 and SAU AGDL15 could be selected to grow further under using supplemental irrigation.