GROWTH AND YIELD OF SOYBEAN AS AFFECTED BY IRRIGATION AND WEED CONTROL METHOD

Abstract

A held experiment was conducted at Sher-e-Bangla Agricultural University. Dhaka during December, 2013 to March,2014 with a view to fmd out the influence of irrigation and weed control method on the growth and yield of Soybean cv. BAR! Soybean 6.The experiment was carried out with four(4) irrigation treatments viz, no irrigation (control), one time(at 20 DAS,two times (at 20 and 40 DAS), three times (at 20. 40, and 60 DAS), and Ibur weed management treatments i.e., no weeding (control), one time hand weeding(at 20 DAS). two times hand weeding (at 20 and 40 DAS) and chemical control by Whip Super® (Fenoxaprop-p-ethyl)0j75g ha at 20 DAS. Results showed different types of weed werefound to infest experimental fields, among them Ec/zinocii/va co/onuin (72. 19%). Lindernia procumbens (28.28%) and Gynodon dacty/on (14.25%) had the highest relative density. It is also noticed that Lindernia procumbens created dominancy throughout the crop growth period even at the later stage of crop. 'three times irrigation (13) gave the highest (1.628 t had) seed yield on the other hand two times hand weeding (Wz) gave the highest (1.556 t ha") seed yield. Interaction effects showed the highest (1.917 t ha") seed yield from the combination of three times irrigation andtwo times hand weeding (13W2). This was also observed that herbicide Whip Super® showed better performance to control grass weeds but failed to control Lindernia procumbens. However, crop plants treated with herbicide became mature one week earlier than other treated crop plants. Considering weed control method of herbicide Whip Super®mav be most economic for cultivation of soybean.