Inorganic fertilization effect on growth and yield attributes of black cumin (Nigella sativa L.) as intercrop under cassia (Cinnamomum tamala)

Abstract: Black cumin (Nigella sativa L.) is an annual flowering plant, belonging to the family Ranunculaceae. It is predominantly grown for its seeds and oil in open condition, but with its short life cycle and low input requirements it has potential for growing as a profitable intercrop. Cassia (Cinnamomum tamala) being perennial and wide spaced crop, it makes possible for cultivation of short duration and closely spaced intercrops during its harvesting period. However, information on nutrient fertilization of black cumin as intercrop remains elusive. The present investigation was conducted at the HRS, Mondouri, BCKV, West Bengal, India with 9 different combinations of inorganic fertilizer in CRBD with 3 replications to find out the optimum combination of nutrients on growth and yield of black cumin as an intercrop with Cassia. Among the various treatments, maximum plant height (68.11 cm), number of primary (6.07) and secondary branches (9) per plant, number of capsule per plant (23.33), 1000 seed weight (2.24g), seed yield hectare^-1 (3.48 q) and B:C ratio (2.20) were recorded with treatment T₅ (70:40:20 kg NPK ha^-1) followed by treatment T₉ (70:40:30 kg NPK ha^-1). Treatment combinations with higher levels of nutrients had significant effects on growth components and seed yield. From the results of this experiment, treatment T₅ (70:40:20 kg NPK ha^-1) can be recommended as the optimum fertilization dose for obtaining maximum growth, seed yield and profitable economic return of black cumin as an intercrop during harvesting period of cassia leaves under alluvial plains of West Bengal.