Incidence of Tetranychus urticae Koch on brinjal under field and screen house conditions

Abstract

The incidence of Tetranychus urticae Koch, a two-spotted spider mite, was studied in brinjal ecosystem (Solanum melongena L.). Brinjal seeds (var. BR112) were raised in the Research Farm area, Department of Vegetable Science, CCS Haryana Agricultural University, Hisar during June 2014 and seedlings were transplanted during mid-July, 2014 in the field. In screen house, the crop was raised during mid-June, 2014. In field and screen house, two-spotted spider mite was recorded to study the population fluctuation on brinjal during the first week of September and continued until the first week of November 2014 at Hisar region. Different stages of T. urticae viz., eggs, larvae, nymphs and adults from ten randomly selected plants were recorded weekly on both ventral and dorsal surface of tender, grown up and older leaves of brinjal. The results revealed that the mite population showed a gradual increase until attainment of the peak in the last week of September 2014. The results clearly showed that 5.19 and 5.85 mites/sq cm leaf T. urticae population peak in the last week of September 2014 on brinjal plant under field and screen house conditions, respectively. Afterwards, a gradual decline in mite population was recorded until November. Mites showed a preference for grown-up leaves of brinjal as compared to tender and older leaves under field and screen house condition.