Abstract

In a field study carried out to determine the percentages of parasitism of the leafminer Liriomyza trifoliiattacking Pisum sativum (nili plantation), the parasitoid Diglyphus isaea was the most abundant recorded parasitoid species of the pest. In addition, a laboratory work was done to ameliorate the risk of herbivory stressby priming the plants with salicylic acid (SA) (1.5 mM) at the vegetative stage. Herbivory induced structural changes in infested leaflets including the rupture of both the upper epidermis and the palisade tissue (the photosynthetic tissue) of the infested plants. Proline is the most remarkable defense strategy in infested plant, while polyamines are in SA treated plants. Finally, it could be concluded that the natural role of the parasitoid D. isaea must be extensively encouraged. Also, using elicitors as salicylic acid to induce resistance of crop plants against herbivores has been successful, and seems to promise as one of the alternative pest management tools.            

Key words: Parasitism, Pisum sativum, Liriomyza trifolii, herbivory, leafminers, salicylic acid, polyamines, proteins.