ON THE ECOLOGY OF THE PEACH TWIG BORER, ANARSIA LINEATELLA (ZELLER) ON APRICOT TREES AT KALUBIA GOVERNORATE, EGYPT

The .peach twig borer, Anarsia lineatella (Zeller) (Lepidoptera : Gelechiidae) is an economic pest on stone fruits in Egypt. The population fluctuation and rate of larval infestation on twigs and fruits of apricot trees were studied for two successive years starting from September, 1992 to October, 1994 at Kalubia Governorate. Sticky delta traps bait­ed with pheromone was used in this study. Data of pheromone catches indicated that males existed all the year round but frequently fluctuateg according to the season of moth activity. During the first season, two remarkable peaks of moth flight were recorded during late September and late May. However, four peaks (during late October, early January, late March and mid June) were noticed during the second season. Two and three main periods of moth activity were approximated in the 1st and 2nd seasons, respectively. Rates of larval infestation were recorded on twigs and on fruits for the 1st and 2nd seasons. From late August to late February, 1st and 2nd instar larvae pass the dormancy period in hi­bernaculae. It was noticed that almost 50% of larval hibernaculae were empty.