Impact of different cotton ( Gossypium spp.) cultivars, as host plant, on development and fertility life-table parameters of Tetranychus urticae (Acari: Tetranychidae).

The effect of five cotton cultivars (Varamin, Mehr, Bakhtegan, Sahel, Saiokra) on the fitness of Tetranychus urticae was assessed by determining the developmental time and fertility life-table parameters for mites on leaf discs at 25 ± 1°C, 70 ± 10% relative humidity and 16:8 hours light:dark photoperiod. To investigate this effect, the duration of each life stage, longevity, reproduction rate and fertility life-table parameters including intrinsic rate of natural increase (r m), net reproductive rate (R 0), mean generation time (T), doubling time (DT) and finite rate of increase (λ) of the two-spotted spider mite on different cotton cultivars were calculated. The results indicated that the Varamin cultivar was the most suitable one for two-spotted spider mite among the tested plants because of its shorter immature developmental period and higher reproduction and intrinsic rate of natural increase, whereas Bakhtegan was the least suitable cultivar because of the longer immature developmental time and the lowest reproduction rate and intrinsic rate of natural increase. The lowest r m value suggests an antibiosis resistance in this cultivar in comparison with other cultivars. [ABSTRACT FROM AUTHOR]