Differential response of vegetable crops to zinc fertilization in Alluvial soils

Abstract

An experiment was conducted during winter (rabi) season of 2005–07 to study the effect of zinc fertilization on carrot (Daucus caroto L.), cauliflower (Brassica oleracea L.) and onion (Allium cepa L.) on Alluvial soil. Application of zinc sulphate up to 30 kg/ha significantly increased the yields and dry matter production of vegetable crops, whereas at higher zinc level (60 kg ZnSO4.7H2O/ha) the yield tended to decrease. The magnitude of response to zinc application differed from crop to crop and were recorded as carrot > cauliflower > onion. Zinc application progressively increased their concentrations and uptake in vegetable crops. The maximum zinc removal was recorded with cauliflower curd and minimum in carrot roots. Zinc application also improved the content and yield of protein of all the vegetable crops. All the 3 vegetable crops gave maximum net returns and B:C ratio with 30 kg ZnSO4.7H2O/ha. The apparent recovery of zinc was influenced by zinc levels with maximum at 30 kg ZnSO4.7H2O/ha except onion where maximum (0.40%) apparent recovery was recorded with 15 kg ZnSO4.7H2O/ha. Better zinc use-efficiency was obtained with application of 15 kg ZnSO4.7H2O/ha. The zinc use-efficiency decreased with its increasing levels and minimum use-efficiency was recorded with 60 kg ZnSO4.7H2O/ha application.M