Modulation in growth, photosynthesis and yield attributes of black mustard (B. nigra cv. IC247) by interactive effect of wastewater and fly ash under different NPK levels

Waste for fertilization of crop plants has received attention during recent years. The present experiment was conducted for a year on Brassica nigra cv. IC247 using two wastes, i.e. fly ash and wastewater with fertilizers and without fertilizers. The crop was irrigated with ground water and wastewater alone and along with the application of different levels of fly ash (FA0, FA10 and FA20) and different levels of NPK (N0P0K0, N40P15K15, N60P30K30 and N80P45K45). Growth, photosynthesis and yield attributes of the test crop were evaluated at different plant age (A). Result showed that wastewater with fertilizers enhanced growth, photosynthesis and yield parameters as compared to that of ground water with fertilizers. The use of fly ash at 20 t ha−1 performed better than 10 t ha−1. Furthermore, the interactive use of wastewater and fly ash proved to be applicable in making N, P and K optimum at their lower doses, as maximum enhancement in growth, photosynthesis and yield was observed with N60P30K30FA20 + WW and further input of N80P45K45FA20 + WW was not beneficial. It was due to the application of fly ash and wastewater has shown the improvement in physiochemical properties of soil and also in the nutrient status.