Major and micronutrient status of vertisols at flowering and harvest of bt. cotton in northern transitional zone of Karnataka

Field survey was conducted to evaluate the major and micronutrient status of Vertisols at flowering and harvest of Bt. cotton in northern transitional zone of Karnataka. Fifty surface soil samples were collected from Bt. cotton growing Vertisols of Bandiwad, Byahatti, Dattur, Hebsur, Ingalalli, Kiresur, Kusugal, Rottigwad, Siraguppi and Sulla villages of Dharwad district during flowering and harvest of Bt. cotton by using GPS and analaysed for major and micronutrients status. The results of the study indicated that available nitrogen, phosphorus, potassium and sulphur varied from 112 to 359, 43.8 to 107.1, 245 to 583 kg ha-1 and 7.5 to 28.4 mg kg-1, respectively. Whereas the micronutrients like copper, iron, manganese and zinc content varied from 0.25 to 0.53, 2.30 to 3.52, 2.83 to 7.35 and 0.40 to 0.69 mg kg-1, respectively during flowering. About 42 to 271 kg ha-1 of nitrogen, 27.59 to 93.47 kg ha-1 of phosphorus, 275 to 540 kg ha-1 of potassium, 4.92 to 25.50 mg kg-1 of sulphur, 0.21 to 0.49 mg kg-1 of copper, 2.23 to 3.47 mg kg-1 iron, 2.86 to 7.27 mg kg-1 of manganese and 0.33 to 0.63 mg kg-1of zinc after harvest of the crop.