The potato rot nematode(Ditylenchus destructor) is a very economically important nematode in agronomic and horticultural plants worldwide. In this study, 43 populations of D. destructor were collected from different h...The potato rot nematode(Ditylenchus destructor) is a very economically important nematode in agronomic and horticultural plants worldwide. In this study, 43 populations of D. destructor were collected from different hosts across China, including 37 populations from Chinese herbal medicine plants. Obtained sequences of ITS-rDNA and D2–D3of 28S-rDNA genes of D. destructor were compared and analyzed. Nine types of significant length variations in ITS sequences were observed among all populations. The differences in ITS1 length were mainly caused by the presence of repetitive elements with substantial base substitutions. Reconstructions of ITS1 secondary structures showed that the minisatellites formed a stem structure. Ten haplotypes were observed in all populations based on mutations and variations of helix H9. Among them, 3 known haplotypes(A–C) were found in 7 populations isolated from potato,sweet potato, and Codonopsis pilosula, and 7 unique haplotypes were found in other 36 populations collected from C. pilosula and Angelica sinensis compared with 7 haplotypes(A–G) according to Subbotin' system. These unique haplotypes were different from haplotypes A–G, and we named them as haplotypes H–N. The present results showed that a total of 14 haplotypes(A–N) of ITS-rDNA have been found in D. destructor. Phylogenetic analyses of ITSrDNA and D2–D3 showed that all populations of D. destructor were clustered into two major clades: one clade only containing haplotype A from sweet potato and the other containing haplotypes B–N from other plants. For further verification, PCR-ITS-RFLP profiles were conducted on 7 new haplotypes. Collectively, our study suggests that D. destructor populations on Chinese medicinal materials are very different from those on other hosts and this work provides a paradigm for relevant researches.展开更多
Given recent higher declines in managed Apis mellifera honeybees,which are the most commonly managed bee species around the world(Garibaldi et al.2013),numerous health threats involved in the losses have been received...Given recent higher declines in managed Apis mellifera honeybees,which are the most commonly managed bee species around the world(Garibaldi et al.2013),numerous health threats involved in the losses have been received great attention.To date,Varroa destructor mite infestation has become the biggest challenge in commercial beekeeping,which is considered as a thorn stuck in the throat of beekeepers.The Varroa mite threatens bee health by absorbing the fat body and hemolymph of immature and mature bees(Ramsey et al.2019).Varroa mite infestation during the development of worker bees was found to reduce birth weight,influence water content and protein level in hemolymph of newly emerged worker bees,decrease flight performance of drones,change gene expression patterns related to immune system of honeybees,and result in honeybee colony losses(Duay et al.2002;Bowen-Walker and Gunn 2010;Zhang et al.2010;Annoscia et al.2012;Dooremalen et al.2013;Locke 2016).The Varroa mite,as an ectoparasite of the honeybee,prefers living in the sealed brood cells(Bogdanov 2006).Thus,bees are more likely to become hosts of mites in the pupal stage.In this study,we systematically investigated the current impacts of V.destructor infestations on the development from capped larvae to emerged bees.展开更多
In this study, a rapid molecular identification method of Tribolium destructor was established with PCR and PCR-RFLP （polymerase chain reaction-restriction fragment length polymorphism） technology. According to the ...In this study, a rapid molecular identification method of Tribolium destructor was established with PCR and PCR-RFLP （polymerase chain reaction-restriction fragment length polymorphism） technology. According to the results, （ 1 ） with PCR method, specific primers were designed based on CO1 gene of T. destructor for PCR amplification, and electrophoresis detection confirmed that PCR method could be used to rapidly and accurately identify T. destructor; （2） with PCR-RFLP method, two pairs of degenerate primers were used to amplify CO1 gene of Tribolium species, PCR products were digested with HindIII and detected by electrophoresis, results indicated that PCR-RFLP method could also be used for rapid identification of T. destructor in quarantine practice.展开更多
The objective of the study was to establish the effect of formic acid on varroa(Varroa destructor),inside the capped brood cells,artificially decapped.The experiments were carried out in 2017-2018 on honeybee colonies...The objective of the study was to establish the effect of formic acid on varroa(Varroa destructor),inside the capped brood cells,artificially decapped.The experiments were carried out in 2017-2018 on honeybee colonies infested with varroa(V.destructor),in a research apiary belonging to the Institute for Beekeeping Research and Development in Bucharest.The decapping method in the present researches used the decapping fork to scrape the capped comb,without affecting the brood,in order to open it for an effective treatment.The combined treatment method was applied on honeybee colonies as a whole,as well as on brood combs,without bees,put in a special treatment box.The researches were focused on establishing the mortality level of various stages of varroa in artificially decapped brood,in normal colony and separately,as well as to make observations on the effect of formic acid on viability of capped bee brood,artificially decapped.The results show a high mortality of varroa,especially the protonymphs and deutonymphs stages(over 80%).The main conclusion is that the brood decapping method combined with formic acid treatment could be a useful technique to control varroa infestation,both in brood and honeybees,shortening strongly the treatment duration as compared to the usual treatments,increasing the efficacy of treatment by cutting the life cycle of varroa in brood.展开更多
Salivary proteins are the initial contact between sedentary insect pests and their host plants. It is expected that one or more salivary proteins mediate the interaction between Hessian fly and wheat, in which a feedi...Salivary proteins are the initial contact between sedentary insect pests and their host plants. It is expected that one or more salivary proteins mediate the interaction between Hessian fly and wheat, in which a feeding site is established to the benefit of the fly. A survey of 52 loci annotated as insect secreted salivary proteins was conducted in 384 individuals evenly distributed among eight biotypes of Hessian fly (B, C, D, E, GP, L, O, and vH9). Amplicons were sequenced with Illumina, and sequence reads were aligned to the reference sequences from which primers had been designed. Positions of consistent base variation (998 in all) were identified and tabulated by biotype. No varying position was associated with biotype-wide virulence to any one of wheat resistance genes H3, H5, H6, H7/H8, H9, H11, H13, and H26. The multiplate pooling strategy utilized in this study is an effective, affordable way to reveal the genotype of hundreds of individuals at tens of genetic loci.展开更多
The Hessian fly, <em>Mayetiola destructor</em>, is a harmful pest of wheat (<em>Triticum aestivum</em>). Pioneer variety 25R78 is putatively tolerant, meaning that the plant can survive success...The Hessian fly, <em>Mayetiola destructor</em>, is a harmful pest of wheat (<em>Triticum aestivum</em>). Pioneer variety 25R78 is putatively tolerant, meaning that the plant can survive successful Hessian fly infestation with reduced growth effects. To understand if Hessian fly-tolerance in wheat results in reduced yield effects and to analyze the economic feasibility of tolerant wheat as a Hessian fly control method, this study focused on analyzing the effect of infestation on tolerant wheat yield. This study analyzed tolerant Pioneer variety 25R78, resistant Pioneer brand variety 25R32, and susceptible Pioneer brand variety 25R47 through harvest. Treated plants were infested using a plastic cover and allowing 1 - 2 female flies to lay eggs for two hours. We measured head, fertile head number and tiller number. Seeds were analyzed by measuring total seed number and weight, as well as average seed number and weight. Tolerant and resistant plants showed no significant effects on yield in comparison to susceptible wheat. The infested tolerant plants were comparable in yield to infested resistant plants. Therefore, we propose that tolerance incorporated into wheat varieties will lower selection pressure on Hessian fly populations and increase the durability of these wheat lines.展开更多
基金supported by the National Natural Science Foundation of China (31760507)the National Key R&D Program of China (2018YFC1706301)。
文摘The potato rot nematode(Ditylenchus destructor) is a very economically important nematode in agronomic and horticultural plants worldwide. In this study, 43 populations of D. destructor were collected from different hosts across China, including 37 populations from Chinese herbal medicine plants. Obtained sequences of ITS-rDNA and D2–D3of 28S-rDNA genes of D. destructor were compared and analyzed. Nine types of significant length variations in ITS sequences were observed among all populations. The differences in ITS1 length were mainly caused by the presence of repetitive elements with substantial base substitutions. Reconstructions of ITS1 secondary structures showed that the minisatellites formed a stem structure. Ten haplotypes were observed in all populations based on mutations and variations of helix H9. Among them, 3 known haplotypes(A–C) were found in 7 populations isolated from potato,sweet potato, and Codonopsis pilosula, and 7 unique haplotypes were found in other 36 populations collected from C. pilosula and Angelica sinensis compared with 7 haplotypes(A–G) according to Subbotin' system. These unique haplotypes were different from haplotypes A–G, and we named them as haplotypes H–N. The present results showed that a total of 14 haplotypes(A–N) of ITS-rDNA have been found in D. destructor. Phylogenetic analyses of ITSrDNA and D2–D3 showed that all populations of D. destructor were clustered into two major clades: one clade only containing haplotype A from sweet potato and the other containing haplotypes B–N from other plants. For further verification, PCR-ITS-RFLP profiles were conducted on 7 new haplotypes. Collectively, our study suggests that D. destructor populations on Chinese medicinal materials are very different from those on other hosts and this work provides a paradigm for relevant researches.
基金supported by the National Natural Science Foundation of China(31760714,31360587)the Academic and Technical Leader Projects of Major Disciplines in Jiangxi Province(20194BCJ22007).
文摘Given recent higher declines in managed Apis mellifera honeybees,which are the most commonly managed bee species around the world(Garibaldi et al.2013),numerous health threats involved in the losses have been received great attention.To date,Varroa destructor mite infestation has become the biggest challenge in commercial beekeeping,which is considered as a thorn stuck in the throat of beekeepers.The Varroa mite threatens bee health by absorbing the fat body and hemolymph of immature and mature bees(Ramsey et al.2019).Varroa mite infestation during the development of worker bees was found to reduce birth weight,influence water content and protein level in hemolymph of newly emerged worker bees,decrease flight performance of drones,change gene expression patterns related to immune system of honeybees,and result in honeybee colony losses(Duay et al.2002;Bowen-Walker and Gunn 2010;Zhang et al.2010;Annoscia et al.2012;Dooremalen et al.2013;Locke 2016).The Varroa mite,as an ectoparasite of the honeybee,prefers living in the sealed brood cells(Bogdanov 2006).Thus,bees are more likely to become hosts of mites in the pupal stage.In this study,we systematically investigated the current impacts of V.destructor infestations on the development from capped larvae to emerged bees.
基金Supported by Science and Technology Project of Jiangsu Entry and Exit Inspection and Quarantine Bureau(2010KJ06)
文摘In this study, a rapid molecular identification method of Tribolium destructor was established with PCR and PCR-RFLP （polymerase chain reaction-restriction fragment length polymorphism） technology. According to the results, （ 1 ） with PCR method, specific primers were designed based on CO1 gene of T. destructor for PCR amplification, and electrophoresis detection confirmed that PCR method could be used to rapidly and accurately identify T. destructor; （2） with PCR-RFLP method, two pairs of degenerate primers were used to amplify CO1 gene of Tribolium species, PCR products were digested with HindIII and detected by electrophoresis, results indicated that PCR-RFLP method could also be used for rapid identification of T. destructor in quarantine practice.
文摘The objective of the study was to establish the effect of formic acid on varroa(Varroa destructor),inside the capped brood cells,artificially decapped.The experiments were carried out in 2017-2018 on honeybee colonies infested with varroa(V.destructor),in a research apiary belonging to the Institute for Beekeeping Research and Development in Bucharest.The decapping method in the present researches used the decapping fork to scrape the capped comb,without affecting the brood,in order to open it for an effective treatment.The combined treatment method was applied on honeybee colonies as a whole,as well as on brood combs,without bees,put in a special treatment box.The researches were focused on establishing the mortality level of various stages of varroa in artificially decapped brood,in normal colony and separately,as well as to make observations on the effect of formic acid on viability of capped bee brood,artificially decapped.The results show a high mortality of varroa,especially the protonymphs and deutonymphs stages(over 80%).The main conclusion is that the brood decapping method combined with formic acid treatment could be a useful technique to control varroa infestation,both in brood and honeybees,shortening strongly the treatment duration as compared to the usual treatments,increasing the efficacy of treatment by cutting the life cycle of varroa in brood.
文摘Salivary proteins are the initial contact between sedentary insect pests and their host plants. It is expected that one or more salivary proteins mediate the interaction between Hessian fly and wheat, in which a feeding site is established to the benefit of the fly. A survey of 52 loci annotated as insect secreted salivary proteins was conducted in 384 individuals evenly distributed among eight biotypes of Hessian fly (B, C, D, E, GP, L, O, and vH9). Amplicons were sequenced with Illumina, and sequence reads were aligned to the reference sequences from which primers had been designed. Positions of consistent base variation (998 in all) were identified and tabulated by biotype. No varying position was associated with biotype-wide virulence to any one of wheat resistance genes H3, H5, H6, H7/H8, H9, H11, H13, and H26. The multiplate pooling strategy utilized in this study is an effective, affordable way to reveal the genotype of hundreds of individuals at tens of genetic loci.
文摘The Hessian fly, <em>Mayetiola destructor</em>, is a harmful pest of wheat (<em>Triticum aestivum</em>). Pioneer variety 25R78 is putatively tolerant, meaning that the plant can survive successful Hessian fly infestation with reduced growth effects. To understand if Hessian fly-tolerance in wheat results in reduced yield effects and to analyze the economic feasibility of tolerant wheat as a Hessian fly control method, this study focused on analyzing the effect of infestation on tolerant wheat yield. This study analyzed tolerant Pioneer variety 25R78, resistant Pioneer brand variety 25R32, and susceptible Pioneer brand variety 25R47 through harvest. Treated plants were infested using a plastic cover and allowing 1 - 2 female flies to lay eggs for two hours. We measured head, fertile head number and tiller number. Seeds were analyzed by measuring total seed number and weight, as well as average seed number and weight. Tolerant and resistant plants showed no significant effects on yield in comparison to susceptible wheat. The infested tolerant plants were comparable in yield to infested resistant plants. Therefore, we propose that tolerance incorporated into wheat varieties will lower selection pressure on Hessian fly populations and increase the durability of these wheat lines.
