EFFECT OF SOME ENDOGENOUS COMPOUNDS EXTRACTED FROM SOME PEAR VARIETIES ON THE LACE PEAR BUGS Stephanitis pyri (F.) (Tingidae : Hemiptera)

Abstract

The results of the effect of phenols. alkaloids and terpens and water extraction extracted from pear leaves varieties. Zafarania. Othmani. LeConte and Calleryana in the lace pear bug have showed significant differences in the expelling and attracting rates according to the chemical compounds. pear variety and the concentration being used and the highest average value of the attracting rate reached 45.33% for the LeConte phenolates. Other extracts showed a difference in its general averages according to the varieties' and extractions. Phenolates. alkaloids and terpens extraction of Calleryana variety has no attracting effect on the lace pear bug. The extractions of Zafarania. Othmani and LeConte varieties have showed low expelling rates which were significantly indifferent with each other as compared to extractions of Calleryana variety which has showed an evident and significant superiority in the expelling rates whose averages reached 51.33. 44.66. 51.33. and 27.33 for phenolates. alkaloids. terpens and the water part of Calleryana values was in favor of the expelling effect on lace pear bug in the extracts of Calleryana as compared to the collation values in favor of the attracting effect in other varieties which explain the resistance of Calleryana against the infection by lace pear bug.