Effect of different fertilizer levels on yield performance of black cumin in Brahmaputra and Jamuna floodplain soil of Bangladesh

Abstract

Although black cumin is an important spice and medical crop, the average yield is low in Bangladesh. The imbalance of fertilizer and local cultivar use are the major causes of the low yield of black cumin. Therefore, an attempt was made to develop and evaluate the performances of different fertilizer doses (in terms of crop productivity and economic performance) for improved varieties of black cumin in the farmers’ field at the Multi Location Testing site, Bhuapur, Tangail in 2017-18 and 2018-19. Treatment included Soil Test Based fertilizer dose - STB (106-32-30-12-2-1 kg NPKSZnB ha-1) as per Fertilizer Recommendation Guide, 2012, STB + 15% extra NPK (122-37-35-12-2-1 kg NPKSZnB ha-1), STB + 30% extra NPK (138-42-39-12-2-1 kg NPKSZnB ha-1) and Farmer’s practice (35-15-19 kg NPK ha-1) and two varieties of black cumin namely V1 = BARI Kalozira-1 and V2 = Local. The experiment was conducted in a Randomized Complete Block Design with six replications. Among the treatment combinations, the highest average seed yield (1.24 t ha-1) and gross margin (Tk. 130179 ha-1) along with BCR (2.74), were obtained from STB with BARI Kalozira-1. The lowest average seed yield (0.54 t ha-1) and gross margin (Tk. 24414 ha-1), along with BCR (1.38), was recorded from a local variety with farmer’s practiced fertilizer dose.