OPTIMIZING PLANTING GEOMETRY FERTILIZER AND IRRIGATION FOR WHITE MAIZE IN DIFFERENT AGROCLIMATIC REGIONS OF BANGLADESH

Abstract

Ten field trials were conducted at three different locations, Sher-e-Bangla Agricultural University (SAU) of Dhaka, Dhamrai Upazilla, Dhaka and Rangpur Sadar Upazilla, Rangpur to evaluate the performance of seven white maize hybrids (PSC-121, KS-510, Changnuo-1, QXiangnuo-1,

Changnuo-6, Yangnuo-7 and Yangnuo-30) under different planting geometries using row to row and plant to plant distance (row to row 50 -70 cm and plant to plant 20-25 cm) for three consecutive rabi seasons of 2015-16 through 2017-18 in Bangladesh. In experiment 1 at SAU, the Changnuo-6 out yielded other varieties when sown at 60cm x 25 cm spacing (8.77 t ha -1 ). In second, third and fourth experiment at SAU, Dhamrai and Rangpur in rabi 2015-16 PSC-121 gave significantly the highest seed yield in all the locations (7.37 - 9.63 t ha ) when planted at 50cm x 25cm spacing. Fifth, sixth and seventh experiments were set at SAU, Dhamrai and Rangpur during the rabi season of 2016-17 using PSC-121 where 50cm x 20cm, 50cm x 25cm and 60cm x 20 cm giving significantly higher yields (9.99-13.87 t ha vi -1 ).

Eighth experiment was set at SAU in the rabi season of 2016-17 to evaluate four varieties under four different irrigation regimes (25+75, 25+50+75, 25+50+75+100 DAS and ‘when required’) where PSC121 showed higher seed yields both with four or ‘when required’ irrigation treatments (10.50 -

11.20

t ha -1 ). Ninth experiment was set also at SAU in the same rabi season of 2016-17 to evaluate different varieties under four different fertilizer levels (Recommended, half of the recommended, 25% more than recommended and 25% less than the recommended) where variety PSC-121, Yangnuo-30 and Changnuo-1 gave significantly higher seed yields (13.9614.84 t ha -1 ) with the applied fertilizer dose of 25% more than recommended. Tenth experiment was set also at SAU in third year rabi season of 2017-18 to evaluate four planting geometries using the variety PSC-121 under two different fertilizer levels (Recommended and 25% more than recommended) where the spacing 50cm x 20cm, 50cm x 25cm and 60cm x 20cm gave significantly higher seed yields (10.93 -11.08 t ha -1 ) with the applied fertilizer dose of 25% more than recommended. It was observed that the grain yield followed the number of grains per ear, 100 grain weight and population density. So, it may be concluded that at all the locations the variety PSC-121 can be grown at 60cm x 20cm planting geometry using the fertilizer dose 25% more than the recommended and four irrigations at 25 DAS+50 DAS +75 DAS+100 DAS. However, to validate the findings, the study may be repeated in all the agro-climatic zones of Bangladesh.