Response of maize to integrated use of organic and inorganic sources of phosphorous with biochar

Soil phosphorous (P) limitation is one of the most important constraint to food production in Pakistan. An experiment comprised of two biochar levels (0 and 10 tons ha-1) and three P sources was designed with an objective to study the integration of organic and inorganic sources of P with biochar for improving maize yield. The P sources included two organic sources i.e. Farmyard manure (FYM) and poultry manure (PM) and an inorganic source i.e. diammonium phosphate (DAP). Experiment was conducted at Agronomy Research Farm of the University of Agriculture, Peshawar during summer 2015 by using randomized complete block design with three replications. FYM, PM and DAP were applied in different ratios of organic and inorganic fertilizers i.e. 100, 75 and 50% of P was obtained from the organic sources and the rest was compensated from the inorganic source to provide a total of 100 kg P ha-1. A control treatment was also included in the experiment for comparison. Statistical analysis of the data showed that more number of days to 75% tasseling and silking with maximum plant height, grains ear-1, grain yield, biological yield, and harvest index were recorded in plots treated with 10 tons ha-1 biochar along with application of 50% organic fertilizer of P and 50% inorganic fertilizer regardless of source of organic fertilizer. It can be concluded that application of P @ 100 kg ha-1 in such a combination that 50% P is applied from organic source (FYM/PM) and 50% P from inorganic source along with biochar (10 tons ha-1) improved yield of maize.