The two-spotted spider mite Tetranychus urticae Koch is one of the most important pests of agricultural crops worldwide, infesting a wide range of plants including some economically important crops. An investigation was carried out to study the life table parameters of five Iranian populations of T. urticae from Urima, Dashtnase, Faryman, Razkan and Tehran under laboratory conditions of 27 °C, 60% RH and 16 L: 8 D hours on Malus domestica Borkh leaves. There was a significant difference in the developmental time of T. urticae among tested populations. The total survival rate of T. urticae ranged from 76% to 81%. The adult longevities were significantly different. The adult longevities of the Faryman and Dashtnase populations were different from the Razkan population. Total fecundity of the Urima, Razkan and Tehran populations were higher than that observed for the other tested populations. The highest value of R0 was for the Urima and Dashtnase populations and the lowest was for the Faryman population. The r values of the Dashtnase (0.248 day-1) and Urima populations (0.200 day-1) were significantly higher in comparison to the Faryman population (0.124 day-1). The observed variation of the two-spotted spider mite collected from different localities showed that ecological factors such as geographical separation can influence the life table parameters of a phytophagous organism.
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