Mortality of pre-imaginal developmental period of Bryobia rubrioculus (Scheuten) (Acari: Tetranychidae) on sweet-cherry and assignment the highest temperature of growth

Brown mite (Bryobia rubrioculus Scheuten) is widely spread around the world. This mite is existed on some orchards in different areas of Iran especially in Hamedan province. In recent years, the mite has become economically important thus; this study was conducted under the lab conditions at 9 constant temperatures (15, 17.5, 20, 22.5, 25, 27.5, 30 and 32.5 35oC), (±0.5); Rh % (60±5) and L: D 16:8, on sweet- cherry leaf discs. Our findings showed that the lowest mortality of pre-imaginal developmental time was at 15 oC (52%) and highest at 32.5 oC (85%). Moreover, it demonstrated that at 35 oC no eggs hatched therefore, this temperature must have been considered as the lethal temperature for the growth mite and so, mortality depends on some environmental factors, particularly temperature effects. Therefore, the results may be used to some aspect of integrated pest management of brown mite in sweet-cherry orchards.