Abstract:
Phosphorus (P) is an essential element for maize but many soils are low in
forms that are readily available to plants to ensure satisfactory growth. A
field research conducted during „Maha’ (2012/2013) season at the research
farm, Faculty of Agriculture, Rajarata University of Sri Lanka examined the
effect of different rates of P on growth and yield parameters of maize (var.
Sampath). The experimental plots were arranged in a Randomized Complete
Block Design with four treatments and four replicates. The treatments were 0
(T1), 20 (T2), 30 (T3) and 40 (T4) kg of P ha-1
. Soil samples were obtained
initially and at 4, 8, 10, 12, and 16 weeks after planting (WAP) and analyzed
for pH, electrical conductivity (EC) and available P. Leaf samples obtained
at 4, 8, 10 and 12 WAP were analyzed for total P. Soil pH, EC, available P
and leaf P content were not significantly different (P<0.05) among
treatments. Plant height at 50% tasseling stage and number of days to 50%
tasseling were significantly higher (P<0.05) in T2 compared to other
treatments. The number of cobs per plant, number of rows per cob and 100-
grain weight were not significantly different among treatments while the
number of kernels per row and number of grains per cob were significantly
higher (P<0.05) in P treatments than the control. Application of 30 kg P ha-1
produced the highest grain yield of maize variety Sampath under the tested
experimental conditions in the dry zone of Sri Lanka.
