Nader Koohpayehzadeh


Ph.D. Candidate

Study of resistance mechanisms in strawberry to tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae), and their impact on Anaphes iole Girault (Hymenoptera: Mymaridae), a parasitoid of the eggs of this pest.

The strawberry Fragaria x ananassa Duchesne (Rosaceae) is one of the most important small fruits in Quebec . Strawberry varieties differ in their susceptibility to pathogens and insect pests. The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae), is a major pest of strawberries in Quebec . The adults and larvae attack the strawberries and feed on the buds, flowers and achenes (seeds). Feeding can cause the death of flowers and deformation of the fruit, known as “button berries” or “catfacing”. The use of resistant cultivars to control this pest is more appropriate than the use of chemical methods due to the resistance of insect pests to insecticides and the negative effects of chemicals on natural environments. However, in order to use resistant cultivars of strawberries in integrated pest management programs to control tarnished plant bug, it is important to determine the effectiveness of natural enemies on these cultivars. In this study, we will establish a correlation between strawberry resistance to tarnished plant bugs and the morphological and physiological characteristics of this plant. We will also study the impact of morphological and physiological variations in certain strawberry cultivars on the ability of natural enemies to use their host on strawberries. To test this hypothesis in strawberries, we will use Anaphes iole (Hymenoptera: Mymaridae), a minuscule egg parasitoid of tarnished plant bugs, which is widespread in Canada and in eastern North America . The results will help researchers produce cultivars that are resistant to this species. Our results may also be used in other plant systems in both theoretical and applied studies of the biological control of insect pests.