Biology of spider mite, Tetranychus urticae (Koch) (Acari: Tetranychidae) on gerbera

The biology of two spotted spider mite, Tetranychus urticae (Koch) was studied on gerbera during summer, monsoon and winter seasons. Duration of egg to adult stage was 18.08±2.47, 21.54±1.60 and 25.36±1.59 days for males and 28.54±2.87, 30.18±2.55 and 53.65±4.85 days for unmated females whereas, it was 24.81±2.57, 23.88±1.66 and 52.15±5.04 days for mated females during three seasons, respectively. An unmated female laid 26.06±8.33, 31.86±6.01 and 19.13±3.85 eggs during her life while the mated female laid on an average 59.24±13.84, 71.80±15.45 and 66.48±10.72 eggs during three seasons respectively. On an average the time taken for completion of the life cycle of the mite on gerbera leaves was 21.66 days for male, 37.47 days for unmated female and 37.29 days for mated female. The average fecundity was 25.77 eggs per unmated female and 64.50 per matedfemale.