Effects of Slow-release Fertilizer on Growth, Yield, and Seed Qualities of Field Corn in Tak Province

Abstract

Field experiment was carried out during November 2011 - April 2012 in northern Thailand at Mae Ra Mad district, Tak province in order to evaluate the effects of slow-release fertilizer applications on growth, yield and seed quality of field corn. The experimental design was a randomized complete block design (RCBD) with 4 replications and 6 treatments. The treatments were as follows; (1) 75 kg/rai of slow-release fertilizer, (2) 100 kg/rai of slow-release fertilizer, (3) 75 kg/rai of slow-release fertilizer incorporated with common chemical fertilizer (4) 100 kg/rai of slow-release fertilizer incorporated with common chemical fertilizer, (5) 100 kg/rai of common chemical fertilizer and (6) no fertilizer as the control treatment. The results showed that the height of field corn obtained by the application of slow-release fertilizers did not significantly differ from the common chemical fertilizer (20-10-10). However, the application of slow-release fertilizer at the rate of 75 kg/rai (25 kg/rai of 13-10-20 as basal application and 50 kg/rai of 25-15-0 at 30 DAP) produced a significantly higher yield than the application of common chemical fertilizer (20-10-10) at the rate of 100 kg/rai (50 kg as basal application, 25 kg at 20 DAP and 25 kg at 40 DAP). In addition, it was found that the seed qualities (100-seed weight, germination rate and germination index) by applied the slow-release fertilizer treatments, did not significantly differ from the common chemical fertilizer (20-10-10). The results from this studies suggested that the application of slow-release fertilizer at the rate of 75 kg/rai (treatment 1) seem to be the most promising fertilizer program for corn seed production in Tak province due to higher efficiency, reduction in fertilizer usage, and decrease the number of applications as a result of reduced labor and production costs.