Influence of Magnesium in Combination with Organics on the Yield and Uptake of Nutrients by Cotton (Gossypium hirsutum L.) Crop in Typic ustropept

A field experiment was conducted to evaluate the effects of magnesium and organic manures on yield and nutrient uptake of cotton (Gossypium hirsutum L.) between 28th Aug 2019 and Jan 2020 in a farmer’s field located at Achchandavilthan village of Srivillipudhur block, Virudhunager district, Tamil nadu. This experiment comprised of fifteen treatment with three replication involving magnesium in combination with organics.The results revealed that the application of MgSO4 at the rate of 50 kg ha-1 along with 250 kg vermicompost for 30 days (1:5 ratio) at critical stages of crop growth along with the Soil Test Crop Response (STCR) based N,P2O5 and K2O registered maximum nutrient uptake of major nutrients Nitrogen (14.25, 23.60 and 43.50 kg ha-1), Phosphorus (6.25,7.80 and 10.34 kg ha-1), Potassium (20.35, 34.50 and 47.45 kg ha-1) 40,70 DAS and harvest stage, secondary nutrient like Calcium(20.54, 33.21 and 69.21 kg ha-1), Magnesium (4.65, 5.75 and 10.50 kg ha-1) 40, 70 Day after sowing (DAS) and harvest stage and micro nutrient Iron (1185.6, 1975.6 and 4865.2 325.80g ha-1), Manganese (380.5, 530.2 and 792.3 325.80 ), Zinc (90.65, 155.72 and 325.60 325.80 ), and Cupper (90.62, 155.70 and 325.80 325.80 ) 40, 70 DAS and harvest stage of crop growth.