Pepper crop residues and chemical fertilizers effect on soil fertility, yield and nutritional status in a crop of Brassica oleracea

Abstract

Effects of pepper crop residues as amendment and their optimal application rates on an agricultural soil have been sparsely studied.A comparative study of the development of a broccoli crop has been conducted using chemical fertilizers (CF) and fresh pepper crop residues (CR) at different application rates during two crop cycles.We measured soil chemical and biochemical properties and broccoli yield, quality parameters and nutritional status.We found that CR at highest application rate increased total N (Nt), potentially mineralizable N (Nmin), microbial biomass N, Nmin/Nt, Nmin/Nsol and urease and alkaline phosphatase activities compared to CF treatment and control (CT).The maximum broccoli yields were obtained in CF3 (383 kg N ha -1 applied as CF) and all CR application rates, especially CR3 (383 kg N ha -1 ); this corresponded with season available N (initial available N plus available N applied as CF or CR) of 545 -598 kg N ha -1 .Results demonstrated that pepper CR applied at the highest rate (16.7 -19.2 t ha -1 ), with a minimum chemical fertilization enhances crop yield and quality, with significant increments in soil quality and fertility compared to chemical fertilization.