Abstrakt

Screening of Common Bean Accessions to Two-Spotted Spider Mite (Tetranychus Urticae Koch.) under Growth Chamber Condition

Alireza Taleei*, Azar Mohammadi, Reza Maali-Amiri, Mohammad Khanjani

The two-spotted spider mite Tetranychus urticae Koch is one of the economically most important pests in a wide range of protected crops worldwide. Due to its short life cycle, abundant progeny and arrhenotokous reproduction, it is able to develop resistance to these compounds very rapidly. Also, Tetranychus urticae is the most important pest of common bean (Phaseolus vulgaris) in Iran, and seedling stage is susceptible to the mite. Therefore, screening and using resistant cultivar of common bean is the most effective strategy to decrease mite damage on crops. In order to finding seedling resistance ten cultivars of common beans (Naz, Dorsa, Akhtar, Pak, 65-062-107, 65-071-98, 65-071-306, 65-071-410, 65-071-400, and 65-071-405) were selected to evaluate resistant mechanisms,morphological and physiological attributes to two-spotted spider mite under growthchamber condition included 25 ± 3°C temperature, RH=55 ± 5% humidity, 14:8(D:L) photoperiod, and 13000 lux light intensity in 2017 at Iran. For evaluatingantixenosis resistance,100 adult female mites were released in the center ofplatform with 100 cm diameter and 40 cm height in which selected leaves isolatedabove and the pots located in the below of platform, as long as the mites werecounted after 72 hours. Antibiosis and tolerant test were studied by counting adultfemale mites after two weeks while, leaf damage scale was evaluated by 1 to 6scoring. According to ANOVA analysis there was significant difference amongresistance mechanisms. It was determined antibiosis mechanism was the mostaccurate test for evaluating of common bean resistance, and there were highcorrelation between antibiosis resistance, leaf thickness and abaxial trichometype. Finally, cluster analysis by Word method showed both of Naz and 65-062-107were grouped as the most tolerant genotypes.