RT Journal T1 INFLUENCE OF SEASONAL DISPARITY ON NPK UPTAKE IN SUNFLOWER A1 F. U. Hassan A1 S. Kaleem JF Journal of Animal and Plant Sciences JO JAPS SN 1018-7081 VO 24 IS 1 SP 190 OP 196 YR 2014 FD 2014/02/01 DO DOI NA AB

Crop-environment interaction is a key factor in the assessment of crop performance, thus nutrients uptake by crop plants require coincidence of vegetative and reproductive stages with suitable environmental conditions. The influence of seasonal variation on NPK uptake in sunflower was studied through field experiments executed at Pir Mehr Ali Shah, Arid Agriculture University Rawalpindi, Pakistan for two years (2007 & 08) during spring and autumn. Four Sunflower hybrids, Alisson-RM, Parasio-24, MG-2 and S-278 were planted in Randomized Complete Block Design with four replications using seed rate of 5 kg ha-1. The data on nitrogen, phosphorus and potassium uptake by plants was recorded at physiological maturity. NKP uptake was significantly influenced by prevailing season. Overall, spring planted crop exhibited significantly higher values for NPK uptake at physiological maturity than during autumn which may be attributed to the longer crop life span facilitating nutrient uptake. However, shorter crop life cycle of autumn planted crop limited uptake. Amongst hybrids, MG-2 took up the maximum quantities of NPK during both the seasons (spring & autumn) probably due to higher yield potential. It may be concluded that farmers planting autumn sunflower should reduce NPK inputs as output would be strongly influenced by shorter growing season.

K1 Seasonal variation; NPK uptake; Sunflower; crop life cycle PB Pakistan Agricultural Scientists Forum LK https://thejaps.org.pk/AbstractView.aspx?mid=2014-JAPS-28