Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, follo...Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, following synthetic blends were made for field experiments: 1) eight-component-attractant blend included Z-3-hexen-1-ol, Z-3-hexenyl acetate, Z-ocimene, Me SA, Z-3-hexenyl butyrate, dodecane, hexadecane and nonanal at 10, 10, 1, 11, 2, 6, 2 and 4 mg mL^-1 in n-hexane, respectively;2) four-component-attractant blend #1 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and nonanal at 2, 10, 10 and 4 mg mL^-1 in n-hexane, respectively;3) four-component-attractant blend #2 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and Me SA at 2, 10, 10 and 11 mg mL^-1 in n-hexane, respectively. Thymol and 1-methoxy-4-methyl-2-(1-methylethyl)-benzene, identified from Lavandula angustifolia aeration samples, significantly repelled the leafhopper as strong repellents when tested alone or in combination at 10 mg mL^-1. For field bioassays, each attractant lure was attached to a bud green sticky board hung from a bamboo stick at above tea plant level for catching the leafhoppers, whereas the repellent dispenser was tied to a tea branch inside tea clump for pushing the leafhoppers away from tea clumps. The results showed that the eight-component-attractant blend caught similar numbers of the leafhopper as did the four-component-attractant blend #1 at about 53–79 leafhoppers/trap/day, which were significantly higher than those on the hexane-control bud green sticky boards. Average leafhopper catches from un-baited sticky boards were about 51–73 leafhoppers/trap/day when pushed by the repellents placed inside tea plants, with the two-component-repellent blend being more effective than their single components. When the two-component-repellent blend was further tested with the three attractant blends in a push-pull fashion, average trap catches ranged from 62 to 92 leafhoppers/trap/day. Control efficacy on 展开更多
Two experiments were conducted to screen 5’ inosine monophosphate,betaine,fish hydrolysate,TMA O and DMPT as feeding stimulants for shrimp.Feeding stimulants carrier was non attractive diet.The first experiment was c...Two experiments were conducted to screen 5’ inosine monophosphate,betaine,fish hydrolysate,TMA O and DMPT as feeding stimulants for shrimp.Feeding stimulants carrier was non attractive diet.The first experiment was conducted to observe the attractant response.The maximum attractant response was attained when the diet contained DMPT.The second experiment was to observe the effect of attractant on growth and FCR of shrimp.The maximum weight gain rate and the minimum FCR was attained when the diet contained DMPT.展开更多
The multicolored Asian lady beetle, Harmonia axyridis(Coleoptera: Coccinellidae), is a common generalist predator in China and is occasionally found gathering on the Chinese pagoda tree, Sophora japonica, in summer. I...The multicolored Asian lady beetle, Harmonia axyridis(Coleoptera: Coccinellidae), is a common generalist predator in China and is occasionally found gathering on the Chinese pagoda tree, Sophora japonica, in summer. In a field investigation, we found that H. axyridis adults preferred S. japonica during its flowering period even though their optimal prey(aphid) is absent at this time. In addition, male and female adults were attracted to S. japonica flowers to a similar extent in a Y-tube olfactometer assay. Using coupled gas chromatography-electroantennogram detection(GC-EAD), we identified a flower odor component(nonanal) that elicited a significant electrophysiological response in H. axyridis. Electroantennogram(EAG) dose-dependent responses revealed that the amplitude of the adult beetle's EAG response increased with increasing concentration of nonanal, peaking at 10 mg mL^(–1). In Y-tube olfactometer behavioral tests, H. axyridis adults preferred a 10 mg mL^(–1) nonanal source over a 100 mg mL^(–1) diluent. Under field conditions, the adults were significantly attracted to both concentrations(10 and 100 mg mL^(–1)), and high concentrations generally had greater attraction. All these results suggest that nonanal, a volatile compound of S. japonica flowers, greatly attracts H. axyridis adults. This study provides a basis for the development of synthetic attractants of H. axyridis, with the potential to promote biocontrol services of this generalist predator in the native area(e.g., China) and to suppress its population by mass trapping in its invasive areas.展开更多
基金financially supported by the National Key Research and Development Program of China (2018YFC1604402)the Natural Science Foundation of Zhejiang Province, China (LY17C140002)+1 种基金the Fundamental and Public Welfare of Zhejiang Province, China (LGN18C160006)the College Student Innovation and Entrepreneurship of Zhejiang Province, China (2017R409055)
文摘Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, following synthetic blends were made for field experiments: 1) eight-component-attractant blend included Z-3-hexen-1-ol, Z-3-hexenyl acetate, Z-ocimene, Me SA, Z-3-hexenyl butyrate, dodecane, hexadecane and nonanal at 10, 10, 1, 11, 2, 6, 2 and 4 mg mL^-1 in n-hexane, respectively;2) four-component-attractant blend #1 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and nonanal at 2, 10, 10 and 4 mg mL^-1 in n-hexane, respectively;3) four-component-attractant blend #2 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and Me SA at 2, 10, 10 and 11 mg mL^-1 in n-hexane, respectively. Thymol and 1-methoxy-4-methyl-2-(1-methylethyl)-benzene, identified from Lavandula angustifolia aeration samples, significantly repelled the leafhopper as strong repellents when tested alone or in combination at 10 mg mL^-1. For field bioassays, each attractant lure was attached to a bud green sticky board hung from a bamboo stick at above tea plant level for catching the leafhoppers, whereas the repellent dispenser was tied to a tea branch inside tea clump for pushing the leafhoppers away from tea clumps. The results showed that the eight-component-attractant blend caught similar numbers of the leafhopper as did the four-component-attractant blend #1 at about 53–79 leafhoppers/trap/day, which were significantly higher than those on the hexane-control bud green sticky boards. Average leafhopper catches from un-baited sticky boards were about 51–73 leafhoppers/trap/day when pushed by the repellents placed inside tea plants, with the two-component-repellent blend being more effective than their single components. When the two-component-repellent blend was further tested with the three attractant blends in a push-pull fashion, average trap catches ranged from 62 to 92 leafhoppers/trap/day. Control efficacy on
文摘Two experiments were conducted to screen 5’ inosine monophosphate,betaine,fish hydrolysate,TMA O and DMPT as feeding stimulants for shrimp.Feeding stimulants carrier was non attractive diet.The first experiment was conducted to observe the attractant response.The maximum attractant response was attained when the diet contained DMPT.The second experiment was to observe the effect of attractant on growth and FCR of shrimp.The maximum weight gain rate and the minimum FCR was attained when the diet contained DMPT.
基金financially supported by the National Key Research and Development Program of China(2017YFD0201900)the National Natural Science Foundation of China(31621064)the earmarked fund for China Agriculture Research System(CARS-15-19)
文摘The multicolored Asian lady beetle, Harmonia axyridis(Coleoptera: Coccinellidae), is a common generalist predator in China and is occasionally found gathering on the Chinese pagoda tree, Sophora japonica, in summer. In a field investigation, we found that H. axyridis adults preferred S. japonica during its flowering period even though their optimal prey(aphid) is absent at this time. In addition, male and female adults were attracted to S. japonica flowers to a similar extent in a Y-tube olfactometer assay. Using coupled gas chromatography-electroantennogram detection(GC-EAD), we identified a flower odor component(nonanal) that elicited a significant electrophysiological response in H. axyridis. Electroantennogram(EAG) dose-dependent responses revealed that the amplitude of the adult beetle's EAG response increased with increasing concentration of nonanal, peaking at 10 mg mL^(–1). In Y-tube olfactometer behavioral tests, H. axyridis adults preferred a 10 mg mL^(–1) nonanal source over a 100 mg mL^(–1) diluent. Under field conditions, the adults were significantly attracted to both concentrations(10 and 100 mg mL^(–1)), and high concentrations generally had greater attraction. All these results suggest that nonanal, a volatile compound of S. japonica flowers, greatly attracts H. axyridis adults. This study provides a basis for the development of synthetic attractants of H. axyridis, with the potential to promote biocontrol services of this generalist predator in the native area(e.g., China) and to suppress its population by mass trapping in its invasive areas.