Abstract:
Maize is the second most important cereal crop grown in Sri Lanka. lt
needs high amount of nitrogen and potassium for better growth and
yield. However, Non-Calcic Brown (NCB) soil is poor in exchangeable
potassium. Therefore, a study was conducted to find out the impact of
increasing the amount of Nitrogen {N) and Potassium {K}on source
and sink development of maize- Tl're experiment was conducted in
split plot design where N was used as the main factor {150 and 2?5
kglha) and K (15, 30, 45 and 60 KzO kglha) tr'/as the sub factor,
lncreasing of N increased developrnent of source components where
chlorophyll content, above ground bio mass and leaf area; sink of
plant where number of grains percob, 100 grain weight and the yield.
Potassium significantly affected on sink except number of grains per
cob. lnteraction of N and K was positively correlated on grains per
cob, hundred grain weight and yield frorn 150 to 225 N kg/ha with all
potassium levels. Hence, split application of N {225 kg/ha) with K (60
KzO kg/ha) would be the optimum level among tested fertilizer
combinations for maize growing in NCB soils.
