Effect of biochar, FYM and nitrogen on weeds and maize phenology.

The proper crop stand and efficient weed control are the two important determinants that directly or indirectly influence crop growth cycle and affect crop productivity. In Pakistan, maize production mainly relies on commercial fertilizers. Presently, the environmental pollution as a result of higher inorganic fertilization has become a burning issue in the field of agriculture. In this connection, in order to evaluate the impact of nitrogen sources on maize phenology and weed control, a field experiment was conducted at the New Developmental Farm of The University of Agriculture, Peshawar, Pakistan in 2011 in a randomized complete block design (RCBD) having three replications. The experiment comprised of 13 fertilizer treatments i.e. control, nitrogen alone (N), farm yard manure alone (FYM), biochar alone (BC) and their various combinations. Data were recorded on days to tasseling, silking and maturity and weeds density at 30 DAS and 60 DAS. All the parameters were significantly affected. Among the treatments biochar, N and FYM application at the rate of 25 ton ha -1 , 10 ton ha -1 and 150 kg ha -1 respectively delayed tasseling, silking and maturity in maize crop. Similarly, biochar application at the rate of 25 ton ha -1 and FYM at the rate of 5 ton ha -1 resulted in lower weeds population both 30 and 60 DAS. On the basis of our experimental results, biochar and FYM applications at the rate of 25 t and 5 t ha -1 are recommended for improving maize growth and efficient weed control.