Effect of phosphorus sources and their levels on spring maize

Abstract

The present study was conducted in order to study the effect of P sources and their levels on spring maize crops at New Developmental Farm, University of Agriculture Peshawar, Pakistan in the year 2014. The farms were divided into low and high permeability strata. Clay loam to silt loam soil textures were observed in low permeability strata while sandy soils were observed in high permeability strata. Soil pH was dominantly alkaline in nature with no salinity indications. More than 75% samples were observed as moderate soil organic matter content. A basal dose of nitrogen 150 kg/ha was applied at sowing time. Hybrid maize was sown with recommended population of 60000 plants/ha. Four phosphorus (P) sources namely Diammonium phosphate (DAP), Nitrophosphate (NP), Triple superphosphate (TSP) and Single superphosphate (SSP), and four P levels (0, 60, 90 and 120 kg/ha) were applied at the time of sowing. Maximum plant height was observed by the application of NP at the rate 120 kg/ha. There was no significant effect of either P levels or P fertilizer sources on number of cobs per plant. Maximum grain per ear, thousand grain weight and highest harvest index was found by the application of SSP at the rate of 90 kg/ha. Higher biological and grain yield were produced when DAP was applied at the rate of 90 kg/ha. Regarding P levels, maximum electrical conductivity of (0.20 dS/m) was recorded for control. Maximum soil mineral nitrogen was recorded when NP was applied, while, highest plant P level was observed in case of SSP.