Effect of Tillage and Soil Moisture Regimes on Nutrient Content and Nutrient Uptake of Post-rainy Season Sunflower (Helianthus annuus L.) in Rice Sunflower Cropping System

摘要

Field experiments were conducted during the post-rainy season of 1997-98 and 1998-99 at University College Farm, Acharya N.G.Ranga Agricultural University, Hyderabad to study the effect of different tillage and soil water regimes on nutrient concentration in plants and nutrient uptake by sunflower crop (Helianthus annuus L.). Five tillage practices, viz., zero tillage, shallow tillage with bullock drawn plough followed by cultivator/ rotavator, deep tillage with mould board plough/ disc plough followed by cultivator/ rotavator were evaluated in main plot, while four levels of soil moisture regimes were assigned to sub plots by providing 60 mm irrigation at IW/CPE = 0.6, 0.8, 1.0 and 1.2 in strip plot design replicated thrice. The N and P contents were more in seed than in stalk, however reverse is true in case of K content. Deep fine tillage created by ploughing once with tractor drawn disc plough followed by twice with rotavator (T_5), recorded significantly higher nitrogen and phosphorus contentsin seed and stalk. Potassium content did not show significant variation. The nutrient uptake (N,P and K) and yields were higher with deep fine tillage over deep .coarse, shallow coarse and zero tillage treatments. In case of soil moisture regimes, irrigation of 6 cm water scheduled at IW/CPE ratio of 1.2 (M_4) and 1.0 (M_3) produced similar higher yields and nutrient uptake and are significantly superior over IW/CPE = 0.8 (M_2) and 0.6 (M_1) moisture regimes. Combined treatments of tillage and soil water regimes significantly increased nutrient uptake for each successive increment in tillage and irrigation levels up to tillage with tractor drawn disc plough once + rotavator with IW/CPE = 1.0, further the difference was insignificant.