The Effect of Stomatic Density and Water Content For Leaves Sensitivity of Some Pear Varieties Towards Infection By The Lace Pear Bug Insect Stephanitis pyri (F.) (Tingidae: Hemiptera)

Abstract

Findings of the current study for the relation between stomatic density water content for leaves sensitivity of some pear varieties towards infection by the lace pear bug, Stephanitis pyri F. have shown a significant and positive correlation between the average numbers of stomatic and water content of the leaves of pear varieties such as Zafarnia, Othmani, Lecont and Calleryana and insects average number per leaf and variety. Regression equations of this relation have shown that the general percentage of the effect of stomatic the average number has reached 96% and 92% for water content in the average number of insects.Calleryana pear variety has shown a resistance towards infection by the lace pear bug compared to other pear varieties which have shown different degrees of sensitivity towards the insect.General average of stomatic density has reached 172.81 , 168.4 , 179.68 and 206.5 stomataml2. and water content of leaves has reached 56.61, 53.69 , 57.78 and 47.45% and insects average number per leaf has reached 21.48 , 22.34 , 31.42 and zero for pear varieties such as Zafarnia, Othmani, Lecont and Calleryana respectively.