Integrated nutrient regimes ameliorate crop productivity, nutritive value, antioxidant activity and volatiles in basil (Ocimum basilicum L.)

Abstract

Basil is a fragrant edible herb with abundant minerals, micronutrients, and pharmacological activities. The effect of organic and chemical fertilizers on the crop biomass, essential oil yield and composition, plant mineral nutrition and antioxidant activity in Ocimum basilicum cv. CIM-SAUMYA (basil) was studied under field conditions. The nutritional quality and antioxidant value of the basil enhanced with the use of different organic and chemical regimes. The field study reveals that the integrated nutrient management comprising poultry manure (PM), farmyard manure (FYM), and chemical fertilizer (CF) gives higher crop yield in basil. PM+CF and FYM+CF treatments produce crop yields that are 60% and 34% higher over the control, respectively. PM+CF resulted in the maximum mean values of chlorophyll-a (0.55mgg−1) and chlorophyll-b (0.063mgg−1). The application of chemical fertilizers culminated in significant changes (p<0.05) in N, P and K contents of basil leaves that were respectively 28%, 36%, and 50% higher over the control. The application of organic fertilizers improved Ca, Mg and vitamin C contents, and antioxidant activity in the basil leaf. The highest level of vitamin C was achieved in the organically amended treatments, i.e., vermicompost (VC) and PM that were 3% higher over the control. The major volatile constituents of the basil oil were methyl chavicol (70.35%–72.60%) and linalool (21.49–30.89%). Other volatile components, i.e., chavicol, β-caryophyllene, α-cadinene, (E)-β-farnesense and γ-muurolene were in a minor amount.