The red turpentine beetle （RTB）, Dendroctonus valens LeConte, as a destructive invasive pest, has become one of the most economically important forest pest in China. Effective control measures are desperately needed...The red turpentine beetle （RTB）, Dendroctonus valens LeConte, as a destructive invasive pest, has become one of the most economically important forest pest in China. Effective control measures are desperately needed. Entomopathogenic fungi, such as Beauveria bassiana, have shown great potential for the management of some bark beetle species. In this study, 12 isolates of B. bassiana from bark beetle were examined for biological characteristics and virulence, to assess their potential as biocontrol agents for RTB. There were significant differences （at P = 0.05） in colony growth rate, conidial yield, conidial germination, tolerance to UV light and extracellular proteases activity among the tested B. bassiana isolates. Isolates, including Bbl801, Bb1906, Bb789 and Bb773, exhibited the best characteristics, because they have faster hyphal growth rate, higher spore production and faster spore germination, higher UV tolerance and protease （Prl） production. The results of a pathogenicity test ofB. bassiana on RTB larvae showed that most isolates of B. bassiana have demonstrated high efficacy and the highest virulent isolate was Bb 1801, which killed 100% of the treated insects and had a median lethal time （LT50） of 4.60 days at a concentration of 1 ×107 conidia/mL. Therefore, isolate Bb1801 has a great potential for sustainable control of RTB in the forest. The correlation between biological characteristics and virulence of the fungal isolates is discussed and the possibility of combination of entomopathogenic fungi with semiochemicals, as one of the promising strategy for RTB control, is considered.展开更多
A Cordyceps specimen was collected in Anhui, China, a strain of Beauveria bassiana, an important ento-mopathogenic fungus for biological pest control, was isolated and their relationship was demonstrated by microcycle...A Cordyceps specimen was collected in Anhui, China, a strain of Beauveria bassiana, an important ento-mopathogenic fungus for biological pest control, was isolated and their relationship was demonstrated by microcycle co-nidiation. The teleomorph is an undescribed species and is named Cordyceps bassiana.展开更多
The entomopathogenic fungus Beauveria bassiana （Balsamo） Vuillemin and predatory mite Neoseiulus barked Hughes are effective biological control agents of Frankliniella occidentalis Pergande （Thysanoptera： Thripida...The entomopathogenic fungus Beauveria bassiana （Balsamo） Vuillemin and predatory mite Neoseiulus barked Hughes are effective biological control agents of Frankliniella occidentalis Pergande （Thysanoptera： Thripidae）, one of the most important pests of ornamentals and vegetables world-wide. Combined application of both may enhance control efficiency. The functional response for N. barked on the first instar larvae of western flower thrips which were infected by B. bassiana for 12 and 24 h in the laboratory （（25＋1）℃, （70＋5）% RH, L：D=16 h：8 h） was determined. The virulence of B. bassiana against the second instar and pupae of the thrips attacked by N. barked were also tested. The results showed that N. barked exhibited a Holling type II functional response on treated thrips. After having been treated with the fungus for 12 h and then offered to the predator, thrips were more vulnerable to be killed by N. barked. The second instar larvae and pupae of the thrips which had been attacked by predatory mites were markedly more susceptible to B. bassiana infection than normal thrips; the cumulative corrected mortality of B. bassiana of the second instar and pupae which were attacked by N. barked were 57 and 94%, respectively, compared to 35 and 80% in controls on the day 8. These findings highlight the potential use of B. bassiana in combination with N. barkeri to control F. occidentalis.展开更多
The alates of the green peach aphid, Myzus persicae, were daily trapped from the air from late October through early January and carried to laboratory for determination of fungal infection by individually rearing them...The alates of the green peach aphid, Myzus persicae, were daily trapped from the air from late October through early January and carried to laboratory for determination of fungal infection by individually rearing them for 7 d on detached cabbage leaves in Petri dishes. Among 760 alates trapped, 266 (35%) were found carrying various fungal pathogens, 87.3% of them died due to mycosis during the first 3-day period of rearing and the rest died in the following two days. Most of the deaths of the alates were attributed to entomophthoralean fungi, taking 94.4%, and the rest were the hyphomycetous fungus Beauveria bassiana. Among the Entomophthorales-killed alates, P. neoaphidis took a proportion of 66.1%, Z. anhuiensis 22.6%, E. planchoniana 9.7%, and N. fresenii 1.6%, respectively. Two alates were found suffering from cross infection of two fungal species, i.e. P. neoaphidis with Z. anhuiensis and N. fresenii, respectively. The results represent the first report on transmission of aphid-pathogenic fungi展开更多
基金We would like to thank Stephen Clarke, USDA Forest Service, for a critical review of the manuscript. Mr Zhen-Wang Miao, the Forest Pest Control Station of Shanxi Province, Tulanchuan Forest Farm, Gujiao, Shanxi Province, who provided logistical support in collecting insects. This study was funded by the State Key Laboratory of Integrated Management of Pest Insects and Rodents （Grant Chinese IPM0702）, the Anhui Provin- cial Natural Science Foundation （070411012, 070411029, TD200708）, the Youth Foundation of Anhui Educational Committee （2008jq1046zd）, the grant of General Administration of Quality Supervision, Inspection and Quarantine of the People＇s Republic of China （2009IK268） and the grant of Anhui Entry-Exit Inspection and Quarantine Bureau （AHKT-04-2008）.
文摘The red turpentine beetle （RTB）, Dendroctonus valens LeConte, as a destructive invasive pest, has become one of the most economically important forest pest in China. Effective control measures are desperately needed. Entomopathogenic fungi, such as Beauveria bassiana, have shown great potential for the management of some bark beetle species. In this study, 12 isolates of B. bassiana from bark beetle were examined for biological characteristics and virulence, to assess their potential as biocontrol agents for RTB. There were significant differences （at P = 0.05） in colony growth rate, conidial yield, conidial germination, tolerance to UV light and extracellular proteases activity among the tested B. bassiana isolates. Isolates, including Bbl801, Bb1906, Bb789 and Bb773, exhibited the best characteristics, because they have faster hyphal growth rate, higher spore production and faster spore germination, higher UV tolerance and protease （Prl） production. The results of a pathogenicity test ofB. bassiana on RTB larvae showed that most isolates of B. bassiana have demonstrated high efficacy and the highest virulent isolate was Bb 1801, which killed 100% of the treated insects and had a median lethal time （LT50） of 4.60 days at a concentration of 1 ×107 conidia/mL. Therefore, isolate Bb1801 has a great potential for sustainable control of RTB in the forest. The correlation between biological characteristics and virulence of the fungal isolates is discussed and the possibility of combination of entomopathogenic fungi with semiochemicals, as one of the promising strategy for RTB control, is considered.
基金This work was supported partly by the National Natural Science Foundation of China (Grant No. 39870013) the Anhui Provincial Natural Science Foundation (Grant No. 98230513) and the Systematic Mycological and Lichenological Laboratory of the Institute
文摘A Cordyceps specimen was collected in Anhui, China, a strain of Beauveria bassiana, an important ento-mopathogenic fungus for biological pest control, was isolated and their relationship was demonstrated by microcycle co-nidiation. The teleomorph is an undescribed species and is named Cordyceps bassiana.
基金supported by the Special Fund for AgroScientific Research in the Public Interest, China (200903032)National Modern Agricultural Science and Technology City Industry of Beijing, China (Z121100001212006)
文摘The entomopathogenic fungus Beauveria bassiana （Balsamo） Vuillemin and predatory mite Neoseiulus barked Hughes are effective biological control agents of Frankliniella occidentalis Pergande （Thysanoptera： Thripidae）, one of the most important pests of ornamentals and vegetables world-wide. Combined application of both may enhance control efficiency. The functional response for N. barked on the first instar larvae of western flower thrips which were infected by B. bassiana for 12 and 24 h in the laboratory （（25＋1）℃, （70＋5）% RH, L：D=16 h：8 h） was determined. The virulence of B. bassiana against the second instar and pupae of the thrips attacked by N. barked were also tested. The results showed that N. barked exhibited a Holling type II functional response on treated thrips. After having been treated with the fungus for 12 h and then offered to the predator, thrips were more vulnerable to be killed by N. barked. The second instar larvae and pupae of the thrips which had been attacked by predatory mites were markedly more susceptible to B. bassiana infection than normal thrips; the cumulative corrected mortality of B. bassiana of the second instar and pupae which were attacked by N. barked were 57 and 94%, respectively, compared to 35 and 80% in controls on the day 8. These findings highlight the potential use of B. bassiana in combination with N. barkeri to control F. occidentalis.
基金This work was partially supported by the "Cheung Kong Scholars Programme', Ministry of Education, P. R. Chinathe National Natural Science Foundation of China (Grant Nos. 30070514 and 39870513).
文摘The alates of the green peach aphid, Myzus persicae, were daily trapped from the air from late October through early January and carried to laboratory for determination of fungal infection by individually rearing them for 7 d on detached cabbage leaves in Petri dishes. Among 760 alates trapped, 266 (35%) were found carrying various fungal pathogens, 87.3% of them died due to mycosis during the first 3-day period of rearing and the rest died in the following two days. Most of the deaths of the alates were attributed to entomophthoralean fungi, taking 94.4%, and the rest were the hyphomycetous fungus Beauveria bassiana. Among the Entomophthorales-killed alates, P. neoaphidis took a proportion of 66.1%, Z. anhuiensis 22.6%, E. planchoniana 9.7%, and N. fresenii 1.6%, respectively. Two alates were found suffering from cross infection of two fungal species, i.e. P. neoaphidis with Z. anhuiensis and N. fresenii, respectively. The results represent the first report on transmission of aphid-pathogenic fungi
