Biochemical Estimations of Tetranychus urticae Koch Infested Marigold Leaves in Summer and Winter Seasons under Screen House and Field Conditions

Abstract

Background: African marigolds an important medicinal and ornamental plant is grown throughout the world. The two spotted red spider mite, Tetranychus urticae is one of the most destructive pests of the crop. Methods: Estimation of various minerals and stress measures of T. urticae infested and non infested leaves was performed in two seasons namely summer and winter under both screen house and field conditions. ANOVA was analysed under two factorial Completely Randomized Design. Mite population per leaf was correlated with each biochemical measures and statistical significance of data was analyzed. Result: Significantly lower nitrogen, phosphorous and potassium content was recorded in infested (2.01, 0.307, 1.509% dry weight) leaves as compared to uninfested leaves (2.93, 0.387, 1.874% dry weight) respectively. Summer season reported higher per cent loss in mineral content as compared to the winter season. The content of total phenol and proline was significantly more in infested leaves (18.75 mg/g, 57.07 µ/100 g) as compared to the uninfested leaves (11.42 mg/g and 47.50 µ/100 g). The per cent increase of phenol and proline ranged from (43.90 and 20.81%) in summer and (42.90 and 17.45%) in winter, respectively.