EFFECT OF IRRIGATION FREQUENCY ON GROWTH AND YIELD OF SOYBEAN

Abstract

Soybean (Glycine max L.) is one of the most nutritious crops in the world which is now a new prospective crop in Bangladesh. A field experiment was conducted at the research field, Hajee Mohammad Danesh Science and Technology University, Dinajpur-5200 during November 2015 to March 2016 with a view to find out the effect of irrigation frequency on the growth and yield of Soybean cv. BARI 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 D AS). At 105 DAS the highest plant height (52.53cm) was found from I2 treatment. On the other hand shortest plant (45.82 cm) was observed from I0 treatment. The highest (5.91) leaf area index was obtained from the treatment of three irrigation (I3) at 90 DAS and the lowest (5.1) leaf area index was recorded from the control (I0). At the 90 DAS highest nodule number I3 (9.208) and lowest nodule number I0 (6.459). The highest (90.09gm) fresh weight was obtained from the treatment I2 at 90 DAS and the lowest (65.64gm) fresh weight was recorded in I0. I3 were produced higher amount of dry matter of (29.50g) and lower amount of dry matter production at harvest (20.67g) in I0 treatment. Results showed that the highest seed yield was observed from I2 (1.638 t ha-1) which was statistically similar with I3 whereas, the lowest was obtained from I0 (1.075 t ha-1). The highest Stover yield was obtained from I3 (1.759 t ha-1 which is statistically similar to I2 (1.754 t ha-1)) whereas the lowest was observed from I0 (1.540 t ha-1) which was statistically similar with I1 (1.566 t ha-1). The highest biological yield was found from I2 (3.425 t ha-1) which is statistically similar to I3 and the lowest was obtained from I0 (2.56 t ha-1. The maximum harvest index was found from I2 (47.71 %), the minimum was obtained from I0 (40.81 %). I2 treatment showed more significant results than the other treatment I0, I1 and I3. So, two times irrigation had significant effect showing the highest yield of 1.638 t ha-1 .