Effect of nitrogen fertilizer on population changes and growth parameters of carmine spider mite, Tetranychus cinnabarinus Boisduval (Acari: Tetranychidae) on different rose cultivars

Carmine spider mite, Tetranychus cinnabarinus Boisduval, is an important pest of ornamental plants such as roses in the world. In this research, population changes and the growth parameters of T. cinnabarinus reared on three rose cultivars (Magic Red, Polar Star, Dolce vita) at different amount of nitrogen fertilization (0, 50 and 100 Kg ha-1) were evaluated at 27±2°C, 70±5% RH and 16: 8 h (L: D) photoperiod. The highest and lowest abundance of mites were observed at levels of 100 and 0 (control) Kg ha-1 nitrogen. In all levels of nitrogen, the density of pest were the highest (79.25) on the Magic Red and lowest on the Dolce Vita variety. Also results showed that on all varieties, the 100 Kg ha-1 nitrogen provided the highest intrinsic rate of increase (rm), finite rate of increase (λ) and net reproductive rate of (R0). By increasing the rate of fertilizer, the doubling time of population (DT) decreased and the mite completed its generation in the shortest time (T). This study revealed that the use of high levels of nitrogen can considerably increase population and reproductive rate of carmine spider mite in rose greenhouse.