M. A. I. SATI1, M. B. HOSSAIN1, M. SALAHIN1, A. K. M. A. BARI2 and M. A. ALIM1*
1Department of Agronomy and Agricultural Extension, University of Rajshahi, Rajshahi-6205, Bangladesh and 2Associate Professor, Department of Crop Science & Technology, University of Rajshahi, Rajshahi-6205, Bangladesh. *Corresponding author’s Email: maalim67@yahoo.com
ABSTRACT
An experiment was conducted at the Agronomy Field Laboratory, University of Rajshahi, Rajshahi, Bangladesh during the period from December 2013 to April 2014 to study the effect of irrigation, variety and time of potassium application on the yield of soybean. The treatments were used in the experiment consisted of three irrigations viz. no irrigation (I0), one irrigation at 20 DAS (I1) and two irrigations at 20 and 40 DAS (I2), two varieties viz. BARI Soybean-5 (V1) and BARI Soybean-6 (V2) and time of potassium application at splits viz. full potassium at sowing (K1), half potassium at sowing and half at flower initiation (K2) and one third at sowing, one third at flower initiation and rest one third at pod development stage (K3). The experiment was laid out in a split-split plot design with three replications by assigning the irrigation to the main plot, variety to the sub plot and time of potassium application to the sub-sub plot. Yield of both varieties increased with the increases of irrigation frequencies and application of potassium in three splits at three stages of soybean. The highest (1.97 t ha-1) and the lowest (1.70 t ha-1) seed yield were obtained from two irrigations (I2) and no irrigation (I0) respectively. BARI Soybean- 6 (V2) gave the highest seed yield (1.90 t ha-1) and the lowest (1.79 t ha-1) was obtained from BARI Soybean-5 (V1). The highest (1.93 t ha-1) and the lowest (1.77 t ha-1) seed yield were obtained from K3 and K1 respectively. So, BARI soybean-6 can be cultivated with two times irrigations at 20 and 40 days after sowing (DAS) and three splits application of potassium, one third at sowing, one third at flower initiation and rest one third at pod development stages is better for maximizing growth, yield and yield attributes of soybean.
Keywords: Irrigation schedules, Variety, Split, Potassium and Soybean.