Abstract:
The use of mineral and organic fertilizer to produce maize in Malawi is essential to ensure high yields, due to a decline in soil fertility. Smallholder farmers however, apply sub-optimal amounts of inorganic fertilizers to produce maize due to high prices. The objective of the study was to evaluate effect of integrating chicken manure and mineral fertilizer on nitrogen uptake, growth and yield of hybrid maize in Malawi as a low cost measure. Field experiments were done in Lilongwe and Zomba districts, in the 2016/17 growing season. The treatments were arranged as a split plot in a randomized complete block design. The main plots were the hybrid maize, SC403 and SC627. The sub plots consisted of six fertilizer treatments: chicken manure (CM); CM and 22.5 kg N; CM and 45 kg N; CM and 67.5 kg N; CM and 90 kg N and a no input control. Chicken manure was applied at a constant rate of 4 t ha-1 and Urea was used as mineral N. Parameters measured included: maize growth parameters; N-uptake; grain yield with its attributes. Gross margin analysis of fertilizer treatments used. Data collected was subjected to analysis of variance using SAS programme and treatments mean were separated using Fishers least significant difference, at 5% probability level. The study indicated that CM and mineral fertilizer integration significantly influenced maize yield and growth parameters. Use of 67.5kg ha-1 N gave the best N-uptake with a mean value of 71.4 mg N plant-1. Maximum girth and height mean values were attained with use of 22.5 kg ha-1 N. Use of 90 kg ha-1 N gave the highest grain yield of 6.3 t ha-1 and Chicken manure (4 t ha-1) + 45kg mineral N had a mean yield of 4.6 t ha-1 which is higher than the average yield of 2.5-3.0 t ha-1. Thus, the use of chicken manure and 45kg ha-1 N and SC627 variety ensures a 50% reduction in the cost of acquiring inorganic fertilizer besides boosting maize production for food security in Malawi.
