Physiological Maturity of Maize as Influenced by Cultivars and Rates of NPK (15-15-15) Fertilizer
A.A. Adeyemi
Department of Agriculture, Wesley University of Science and Technology,
P.M.B. 507, Ondo, Ondo State
Correspondence: draadeyemi@yahoo.com Tel: 234-8034074060
Accepted on July 10, 2013
Abstract
A field trial to determine the effects of cultivars and rates of NPK (15-15-15) fertilizer on the physiological maturity of maize (Zea mays L.) was conducted for a duration of 2 years at the Research Farm of the University of Ado-Ekiti in the rain forest zone of the South-western Nigeria. Commercial NPK (15-15-15) fertilizer was applied to DMRESR-Y, SUWAN-Y and DMRLSR-Y maize cultivars at 0, 250, 500 and 750 kg/ha. Results revealed that physiological maturity differed significantly among the three varieties of maize with DMRLSR-Y having the longer days to tasseling, silking, leaf browning and black layer formation than those of SUWAN-Y and DMRESR-Y while the periods to all the maturity factors were statistically similar in SUWAN-Y and DMRESR-Y. Period of physiological maturity (black layer formation) and the processes leading to it also decreased with the increasing rates of NPK (15-15-15) fertilizer up to 500kg/ha and thereafter stabilized or formed a plateau.