SUSCEPTIBILITY OF SOME STARWEBERRY CULTIVARS TO THE INFESTATION OF TETRANYCHUS URTICAE KOCH

The relative susceptibility of six strawberry cultivars (Chandler sweet charll Branko, style , Helda and Almont) to the infestation with the two spotted mite Tetranychus urticae Koch was studied in Al kanater Research station Qualubia Governorate , through two successive seasons (2010/2011) and (2011/2012) . Evaluation of mite infestation was estimated according to the other mean number of eggs and immature stages, results showed that the population dynamics of spider mites infestation in the six cultivars appear in few numbers during the period from October until February. The infestation increased during March and reaches until February the infestation increased during march and reaches the maximum during April and decreases. The results also showed that sweetcharll and Chandler are the least preferable varieties, while Almont and Helda where the most preferable varieties to spider mite infestation . Based on these conclusions, Sweetcharll and Chandler varieties are recommended for the strawberry growers in order to depress the population density of the mite T. urticae in the strawberry fields in Egypt.