Egg parasitoids are known to use a wide range of chemicals, emitted by plants, host eggs or adults, for host selection. The effect of the sex pheromone components of the lepidopteran olive pests Prays oleae （Lepidopt...Egg parasitoids are known to use a wide range of chemicals, emitted by plants, host eggs or adults, for host selection. The effect of the sex pheromone components of the lepidopteran olive pests Prays oleae （Lepidoptera： Yponomeutidae） and Palpita unionalis （Lepidoptera： Pyralidae） was studied under laboratory conditions, on the foraging behaviour of the egg parasitoid Trichogramma oleae （Hymenoptera： Trichogrammatidae）. The re- sponse of T. oleae wasps to （Z）-7-tetradecenal and （E）-1 l-hexadecenal, major sex phero- mone components ofP. oleae and P. unionalis respectively, depended on the dose of the pheromone used in a Y-tube olfactometer bioassay. （E）-11-hexadecenal elicited maximum attraction （70%） at a dose of 1 pg, while a dose of 100 pg （Z）-7-tetradecenal attracted 80% of the tested wasps. （E）-11-hexadecenyl acetate, the second sex pheromone component of P. unionalis, and the binary blend of（E）-i 1-hexadecenyl acetate： （E）-11-hexadecenal （7：3） were not attractive at these doses. The results of this research are discussed in view that they may be considered as alternatives in the biological control of these pests.展开更多
Prays oleae Bern, （OM） andPalpita unionalis Hfib., （JM） are two of the most important pests in olive groves in Egypt. A 3-year monitoring study using sex pheromone traps in semi-arid and arid olive groves was perf...Prays oleae Bern, （OM） andPalpita unionalis Hfib., （JM） are two of the most important pests in olive groves in Egypt. A 3-year monitoring study using sex pheromone traps in semi-arid and arid olive groves was performed. In the semi-arid grove, flight pattern of the OM was the same as in other Mediterranean countries, but in dates concordating plant phenology. The moth completes three generations annually： the first flight is in March to April, the second is in May to June and the third occurs in August to October. In the arid olive grove, an interesting flight pattern was observed. First flight was always very close or overlapped with the second one with no male catches during August to October. However, eggs were present most of the season, indicating unusually high female presence and oviposition activity of the OM during the absence of males in the traps. Generally, moth densities were significantly lower in low fruiting years than in higher ones and were also lower in the arid olive grove than in the semi-arid one. In contrast, JM males were present all season, exhibiting six to seven and three to four overlapping flight peaks in arid and semi-arid olive groves, respectively. Moth densities were significantly higher in the arid olive grove than those in the semi-arid one. This study shows that trapping location and fruit beating year are characteristics that strongly affect the grove-specific information needed to estimate correctly adult emergence and thus the timing of control measures.展开更多
文摘Egg parasitoids are known to use a wide range of chemicals, emitted by plants, host eggs or adults, for host selection. The effect of the sex pheromone components of the lepidopteran olive pests Prays oleae （Lepidoptera： Yponomeutidae） and Palpita unionalis （Lepidoptera： Pyralidae） was studied under laboratory conditions, on the foraging behaviour of the egg parasitoid Trichogramma oleae （Hymenoptera： Trichogrammatidae）. The re- sponse of T. oleae wasps to （Z）-7-tetradecenal and （E）-1 l-hexadecenal, major sex phero- mone components ofP. oleae and P. unionalis respectively, depended on the dose of the pheromone used in a Y-tube olfactometer bioassay. （E）-11-hexadecenal elicited maximum attraction （70%） at a dose of 1 pg, while a dose of 100 pg （Z）-7-tetradecenal attracted 80% of the tested wasps. （E）-11-hexadecenyl acetate, the second sex pheromone component of P. unionalis, and the binary blend of（E）-i 1-hexadecenyl acetate： （E）-11-hexadecenal （7：3） were not attractive at these doses. The results of this research are discussed in view that they may be considered as alternatives in the biological control of these pests.
文摘Prays oleae Bern, （OM） andPalpita unionalis Hfib., （JM） are two of the most important pests in olive groves in Egypt. A 3-year monitoring study using sex pheromone traps in semi-arid and arid olive groves was performed. In the semi-arid grove, flight pattern of the OM was the same as in other Mediterranean countries, but in dates concordating plant phenology. The moth completes three generations annually： the first flight is in March to April, the second is in May to June and the third occurs in August to October. In the arid olive grove, an interesting flight pattern was observed. First flight was always very close or overlapped with the second one with no male catches during August to October. However, eggs were present most of the season, indicating unusually high female presence and oviposition activity of the OM during the absence of males in the traps. Generally, moth densities were significantly lower in low fruiting years than in higher ones and were also lower in the arid olive grove than in the semi-arid one. In contrast, JM males were present all season, exhibiting six to seven and three to four overlapping flight peaks in arid and semi-arid olive groves, respectively. Moth densities were significantly higher in the arid olive grove than those in the semi-arid one. This study shows that trapping location and fruit beating year are characteristics that strongly affect the grove-specific information needed to estimate correctly adult emergence and thus the timing of control measures.
