RASPBERRY CANE MIDGE - Resseliella theobaldi (Barnes) - FLIGHT AND EGG LAYING DYNAMICS ON RASPBERRY FRUITING ON TWO YEAR OLD CANES

摘要

The raspberry cane midge, Resseliella theobaldi (Barnes), is a very important pest of raspberry plantations in Poland. Larvae of the pest damage primocanes on all of the raspberry cultivars, both these fruiting on two-year-old canes in June-July as well as those fruiting on primocanes in August - September. The larvae are feeding under the skin of primocane and cause damage to it. The canes are weak and dry up before harvest. The experiments were carried out during 2006-2007 in central Poland. The dynamics of midge's flight was monitored weekly in not protected, commercial raspberry plantation using standard pheromone traps. The standard white delta traps (20 x 20 cm. base) with the raspberry cane midge sex pheromone "racemate" were placed at a height of 0.5 in above soil. Numbers of eggs and larvae were monitored in artificial splits on primocanes.In Poland, the midge develops usually three generations a year. The flight starts at the end of April or at the beginning of May and lasts during the whole growing season, until beginning of October. On an unprotected raspberry plantation, cultivar 'Mailing Promise', fruiting on two year old canes, intensive flight of the first generation of midges was noted in the first or second half of May, depending on the year. The most intensive flight of the pest's second generation was noted in the last decade of June and at the beginning of July, just before and during the harvest. The highest number of third generation males was noted on sticky traps in August, after 'Mailing Promise' fruit harvest.The best time to control the midges is early spring, before blossom of raspberry fruiting on two year old canes and in summer, after harvest of mentioned cultivars.