Object: To investigate the VOCs from living Prunus persica flowers of different branches and their correlation with floral insects. Special, dominant and 20 VOCs were analysed from living Prunus persica flowers captur...Object: To investigate the VOCs from living Prunus persica flowers of different branches and their correlation with floral insects. Special, dominant and 20 VOCs were analysed from living Prunus persica flowers captured by closely and circularly headspace way in adsorbent tubes and ATD-GC/MS on 29 April in Wanbailin Ecological Garden, China. VOCs from high altitude tree are more than low altitude in sunny site, and floral volatile constituents from upslope branches are less than downslope of the same tree on high altitude. Special floral VOCs were alpha-dimethyl-benzenemethanol, isopropyl palmitate, ethylbenzene, p-xylene, acetophenone, 3-ethyl-2-methyl-Heptane on sunny slope, and propylene glycol, decanal, hexadecane on shady slope. Dominant VOCs founded during 8 temporal quanta were toluene, hexane, 2-ethyl-1-hexanol, dodecane, pentadecane. Floral VOCs’ number from sunny slope was significantly negative correlated with flower-visiting insect community richness, abundance, diversity on sunny or shady slope, which from shady slope was significantly positive correlated with flower-visiting insect community parameters on both slopes tried dividing insects visiting floral branches from Prunus persica in sunny site with n/2 + 1 or n/2 - 1, and shady site with n/2 before sampled volatiles day. On sampled volatiles day, 2-ethyl-1-hexanol from sunny slope was significantly positive correlated with flower-visiting insect community parameters on shady slope (P Prunus persica on sunny slope, and even floral branches kept on shady slope.展开更多
Information is lacking regarding the visual cues used by Helicoverpa armigera moths during nectar feeding. Here, we investigated the preference for radial gradient patterns in H. armigera moths. The results indicated ...Information is lacking regarding the visual cues used by Helicoverpa armigera moths during nectar feeding. Here, we investigated the preference for radial gradient patterns in H. armigera moths. The results indicated that both sexes shared a preference to plain flower models of blue and cyan. The radial gradient pattern (cyan as nectar guide color and blue as petal color) was more attractive than its component plain colors (cyan or blue), especially in male moths. Number of corolla petals did not influence the attractiveness of the cyan-blue pattern. The addition of a tertiary floral attractant to white-blue or cyan-blue radial gradient patterns could dramatically enhance the attractiveness of visual cues in males rather than females, suggesting that males gave a higher weight in olfactory modality than females gave, while females gave a higher weight in vision modality than males gave. All together, we found an optimal combination of floral cues in H. armigera sexes as follows: A tertiary floral attractant (2 μL dose of phenylacetaldehyde, benzyl acetate, and salicylaldehyde mixed in 26:15:2) added to white-blue radial gradient flower model (3 cm in diameter). To our knowledge, this is the first time that rose curve and radial gradient tools were used to simulate floral pattern in the studies of flower-visiting insects.展开更多
Unlike European species,the potential of Nearctic syrphids as biological control agents is still poorly studied.However,the American hoverfly,Eupeodes americanus(Wiedemann),has recently demonstrated promising traits a...Unlike European species,the potential of Nearctic syrphids as biological control agents is still poorly studied.However,the American hoverfly,Eupeodes americanus(Wiedemann),has recently demonstrated promising traits as a biocontrol agent,notably against the foxglove aphid,Aulacorthum solani Kaltenbach,on pepper.The present study aims to extend our knowledge of the American hoverfly by evaluating its potential as a biocontrol agent in a banker plant system against the melon aphid,Aphis gossypi Glover,in a greenhouse cucumber crop.The preimaginal development and voracity of E.americanus were compared when preying upon the focal prey/pest(A.gossypi)or the banker prey(bird cherry-oat aphid,Rhopalosiphum padi L.)by daily observations of larvae from egg to adult.Preimaginal development time,survival rate,and occurrence of deformation were similar on both prey species.The weight of third instar and pupae,however,was higher for larvae that fed on the banker prey.The ad libitum voracity of the syrphid larvae was generally very high and did not significantly differ between prey species,except for the third-instar larvae which consumed more focal prey.Results suggest that a banker plant system involving the bird cherry-oat aphid may be a promising tactic for utilizing E.americanus for melon aphid biocontrol.展开更多
文摘Object: To investigate the VOCs from living Prunus persica flowers of different branches and their correlation with floral insects. Special, dominant and 20 VOCs were analysed from living Prunus persica flowers captured by closely and circularly headspace way in adsorbent tubes and ATD-GC/MS on 29 April in Wanbailin Ecological Garden, China. VOCs from high altitude tree are more than low altitude in sunny site, and floral volatile constituents from upslope branches are less than downslope of the same tree on high altitude. Special floral VOCs were alpha-dimethyl-benzenemethanol, isopropyl palmitate, ethylbenzene, p-xylene, acetophenone, 3-ethyl-2-methyl-Heptane on sunny slope, and propylene glycol, decanal, hexadecane on shady slope. Dominant VOCs founded during 8 temporal quanta were toluene, hexane, 2-ethyl-1-hexanol, dodecane, pentadecane. Floral VOCs’ number from sunny slope was significantly negative correlated with flower-visiting insect community richness, abundance, diversity on sunny or shady slope, which from shady slope was significantly positive correlated with flower-visiting insect community parameters on both slopes tried dividing insects visiting floral branches from Prunus persica in sunny site with n/2 + 1 or n/2 - 1, and shady site with n/2 before sampled volatiles day. On sampled volatiles day, 2-ethyl-1-hexanol from sunny slope was significantly positive correlated with flower-visiting insect community parameters on shady slope (P Prunus persica on sunny slope, and even floral branches kept on shady slope.
基金supported by the National Natural Science Foundation of China(31900345)the Natural Science Basic Research Plans in Shaanxi Province of China(2021JQ-757,2019JZ-34)+2 种基金the Scientific Research Program Funded by Shaanxi Provincial Education Department(21JK0555)the Foundation of Shaanxi University of Technology(SLGRC13)the Opening Foundation of Shaanxi University of Technology(SLGPT2019KF02-02)。
文摘Information is lacking regarding the visual cues used by Helicoverpa armigera moths during nectar feeding. Here, we investigated the preference for radial gradient patterns in H. armigera moths. The results indicated that both sexes shared a preference to plain flower models of blue and cyan. The radial gradient pattern (cyan as nectar guide color and blue as petal color) was more attractive than its component plain colors (cyan or blue), especially in male moths. Number of corolla petals did not influence the attractiveness of the cyan-blue pattern. The addition of a tertiary floral attractant to white-blue or cyan-blue radial gradient patterns could dramatically enhance the attractiveness of visual cues in males rather than females, suggesting that males gave a higher weight in olfactory modality than females gave, while females gave a higher weight in vision modality than males gave. All together, we found an optimal combination of floral cues in H. armigera sexes as follows: A tertiary floral attractant (2 μL dose of phenylacetaldehyde, benzyl acetate, and salicylaldehyde mixed in 26:15:2) added to white-blue radial gradient flower model (3 cm in diameter). To our knowledge, this is the first time that rose curve and radial gradient tools were used to simulate floral pattern in the studies of flower-visiting insects.
基金supported by the Ministere de I'Agriculture,des Pecheries et d'Alimentation du Quebec(MAPAQ),following the program Prime-Vert[grant number18-009-UQAM]by a CRSNG discovery grant to Eric Lucas.
文摘Unlike European species,the potential of Nearctic syrphids as biological control agents is still poorly studied.However,the American hoverfly,Eupeodes americanus(Wiedemann),has recently demonstrated promising traits as a biocontrol agent,notably against the foxglove aphid,Aulacorthum solani Kaltenbach,on pepper.The present study aims to extend our knowledge of the American hoverfly by evaluating its potential as a biocontrol agent in a banker plant system against the melon aphid,Aphis gossypi Glover,in a greenhouse cucumber crop.The preimaginal development and voracity of E.americanus were compared when preying upon the focal prey/pest(A.gossypi)or the banker prey(bird cherry-oat aphid,Rhopalosiphum padi L.)by daily observations of larvae from egg to adult.Preimaginal development time,survival rate,and occurrence of deformation were similar on both prey species.The weight of third instar and pupae,however,was higher for larvae that fed on the banker prey.The ad libitum voracity of the syrphid larvae was generally very high and did not significantly differ between prey species,except for the third-instar larvae which consumed more focal prey.Results suggest that a banker plant system involving the bird cherry-oat aphid may be a promising tactic for utilizing E.americanus for melon aphid biocontrol.
