برريس بيولوژي سنگ صنوبر )MULS. DSREY( HET: TINGIDAE MONOST EIRA UNICOSTA TA در كرج

Life- history study of poplar lace bug, Monosteira unicostata (Muls. & Rey) Het.: Tingidae in Karaj

Poplar lace bug is one of the most important pests of poplar trees in Karaj. During 1996-1997, activity of the pest was studied with weekly sampling of poplar trees in Karaj Alborz Research Complex. Biology of the pest was studied in the field conditions on pot-grown seedlings. Poplar lace bug overwinters as adults inside the bark crevices of trunk and large branches of host trees, or beneath the dried leaves or debris around tree bases. Activity of the pest started from late April. Egg-laying started from late April or early May and females laied the eggs inside leaf parenshima. The average number of eggs per overvintering female was 41/33 and the average oviposition period was 11/33 days. The insect had five instar nymphes. The nymphes often formed the clones beneath the leaves and sucked sap of leaves and remained their feces at this place. The first generation adults appeared on poplar trees from early June and egg-laying started from mid June. The second and third generation adults appeared on poplar trees from early and late July respectively and for the forth generation adults from mid or late August. In Karaj area, the insect had 3-4 generations per year. Based on our investigation on pot-grown seedlings, average life-span for first, second and part of the third generation insects were 46.76, 47.02 and 42.2 days respectively. Life-span for overwintering adults ( the third and forth generation) including winter diapouse was about 8 months.