Yield Response of Black Gram to Nitrogen, Phosphorous and Potassium Combinations Grown in Khulna District of Southwestern Coastal Bangladesh

Nitrogen, phosphorous and potassium have significant influence on physiological growth and yield of black gram. There is no specific nutrient recommendation for black gram in this region. Nutrient requirement of black gram needed to be assessed in the coastal area of southwestern Bangladesh. Therefore, the field experiment was conducted at the Field Laboratory of Agrotechnology Discipline, Khulna University during Kharif-I season (March-July) to evaluate the effect of different rates of NPK on growth, yield and yield attributes of black gram (BARI Mash-3). The experiment comprised of four treatments viz. F0 = Control (no nutrient added), F1 = NPK-12:15:18 kg ha-1, F2 = NPK-16:20:24 kg ha-1 and F3 = NPK-20:25:30 kg ha-1. The experiment was laid out in randomized complete block design with four replications. NPK rates had substantial influence on growth, yield and yield attributes of black gram. Growth, yield and yield attributes were increased with the increment of NPK rates. The highest plant height (62.62 cm), number of branch plant-1 (11.00), number of pod plant-1 (27.44), number of seed pod-1 (7.89), 1000 seed weight (43.78 g), seed yield (1.72 t ha-1), stover yield (4.22 t ha-1) and harvest index (29.13%) were obtained from 20:25:30 kg NPK ha-1 while lowest value of all the parameters were obtained from no NPK added plot. Results of this experiment revealed that NPK @ 20:25:30 kg ha-1 could be the best for the cultivation of black gram (BARI Mash-3) in Khulna region of southwestern coastal Bangladesh.