The potato psyllid Bactericera cockerelli(Hemiptera:Triozidae)has recently emerged as a serious pest of potatoes and other solanaceous crops.It causes direct feeding damage and also vectors Candidatus Liberibacter sol...The potato psyllid Bactericera cockerelli(Hemiptera:Triozidae)has recently emerged as a serious pest of potatoes and other solanaceous crops.It causes direct feeding damage and also vectors Candidatus Liberibacter solanaceaerum(Lso),a pathogen that causes zebra chip disease in potatoes and which potentially costs growers millions of dollars each year.Such producers rely on frequent sprays of pesticides for psyllid control but the results are unsatisfactory and there are negative side effects.The psyllid has spread beyond its native range in southwest US and northern Mexico to Canada,El Salvador,Honduras,Guatemala and Nicaragua via medium to long range dispersal flights perhaps aided by wind currents,and through anthropogenic means.It was accidentally introduced into New Zealand in 2006 and most recently Australia,most likely through the importation of infested plant material.This review summarizes information from studies on the biology,impact and management of B.cockerelli,and highlights the imminent risk of this insect and its associated pathogen invading China,the world’s largest producer of fresh potatoes.Development of risk maps leading to increased surveillance,could prevent or delay an incursion and facilitate early detection or eradication should this occur.Long-term management with Lso-tolerant potato cultivars and psyllid control using the parasitic wasp Tamarixia triozae and other natural enemies should be pursued,rather than depending on synthetic pesticides.展开更多
The psyllid Bactericera cockerelli was first reported in New Zealand in 2006 and spread quickly throughout all potato growing regions.In 2009,B.cockerelli was associated with the plant pathogenic bacterium Candidatus ...The psyllid Bactericera cockerelli was first reported in New Zealand in 2006 and spread quickly throughout all potato growing regions.In 2009,B.cockerelli was associated with the plant pathogenic bacterium Candidatus Liberibacter solanacearum,the putative causal agent of zebra chip disease in potato.Both the psyllid and the bacterium have non-crop host plants which can serve as reservoirs when the crop is not available.Growers apply different management strategies that fit integrated pest management programmes to manage B.cockerelli and subsequently lower incidence of zebra chip disease in potato crops.Despite best management efforts,complete control of B.cockerelli and zero incidence of zebra chip disease are not achievable at the current time.展开更多
Tomato crops(Physalis ixocarpa Brot.)are produced in almost all Mexico,part of the United States and Central America.Recently the tomato production has suffered economic losses of 70%to 80%due the presence of yellowin...Tomato crops(Physalis ixocarpa Brot.)are produced in almost all Mexico,part of the United States and Central America.Recently the tomato production has suffered economic losses of 70%to 80%due the presence of yellowing and floral abortion,whose causal agent has been attributed to the presence of phytoplasma;an insect vector of these phytoplasma is Bactericera cockerrelli Sulc.Alternative control of this psyllid has lacked effectiveness because their spatial distribution is unknown within tomato plots.This study aimed to determine the spatial distribution of populations of nymphs of B.cockerelli in four tomato plots,the determination of the spatial distribution was performed by means of geostatistics.The experimental semivariogram was determined to adjust to a theoretical model(spherical,exponential or Gaussian)through the program Variowin 2.2,the adjustment was validated with the method of cross-validation and aggregation maps of the pest were obtained through Kriging with Surfer 9.0 program.The short-term time-space stability of the pest was determined through the tests Crámer-von Mises.The results showed that populations of nymphs of B.cockerelli have a distribution of aggregate type,which was corroborated by density maps.Infestations are not present in 100%of the surface of the experimental plots,which helps to direct control measures on specific areas of infestation.展开更多
The potato/tomato psyllid Bactericera cockerelli causes serious damage to several solanaceous crops by direct feeding and vectoring Candidatus Liberibacter solanacearum,a bacterial pathogen.Electron beam(eBeam)irradia...The potato/tomato psyllid Bactericera cockerelli causes serious damage to several solanaceous crops by direct feeding and vectoring Candidatus Liberibacter solanacearum,a bacterial pathogen.Electron beam(eBeam)irradiation is an environmentally friendly,chemical-free alternative method that is increasing in use for disinfestation of insect pests.We hypothesize that this irradiation technology will have detrimental effects on potato psyllid and thus impede its disease vectoring.To this end,we explored the effects of eBeam treatment ranging from 50 to 500 Gy on survival,development and reproduction of this pest.Impact on psyllids was apparently dose-dependent.When irradiated at 350 Gy,eggs could not hatch,1st instar nymphs failed to emerge,and although a small portion of irradiated 5th instar nymphs survived,the emerged adults were mostly deformed.Abnormality in eclosed adults suggests harmful effects of eBeam on metamorphosis.Reproduction was seriously impaired when female psyllids were exposed to eBeam at the 5th instar nymphal or young adult stage,presumably due to inability to form oocytes.In addition,reciprocal crosses between irradiated and untreated psyllids indicated that female psyllids were more radiosensitive than males to eBeam.Taken together,these findings indicate that eBeam negatively impacted potato psyllid development and reproduction,which would inevitably compromise its disease transmission capacity.A dose of 350 Gy can be considered as a reference dose for effective control of potato psyllids.展开更多
The impacts of potato psyllid （Bactericera cockerelli） feeding on potato foliage on the free amino acids （FAAs） composition in potato leaf and tubers were determined under greenhouse conditions. The free amino aci...The impacts of potato psyllid （Bactericera cockerelli） feeding on potato foliage on the free amino acids （FAAs） composition in potato leaf and tubers were determined under greenhouse conditions. The free amino acids in plant extracts were separated by high-performance liquid chromatography, and in both leaf and tuber samples, at least 17 FAAs were detected. Psyllid feeding significantly changed the levels of several FAAs in both leaf and tuber samples. The concentration of leucine increased 1.5-fold, whereas that of serine and proline increased 2- and 3-fold, respectively. In contrast, the concentrations ofglutamic acid, aspartic acid and lyscine were significantly reduced by 42.0%, 52.1% and 27.5%, respectively. There were also significant changes in the levels of FAAs in the Zebra chip （ZC） infected tubers compared with the healthy tubers, and the levels of six of the FAAs increased, and the levels of nine of the FAAs decreased. The results from this study indicate that potato psyllid causes major changes in free amino acid composition of plant tissues, and this change in plant metabolism may contribute to the plant stress as indicated by increased levels of proline in the leaves and hence promoting the development of plant diseases such as ZC disease.展开更多
基金funded by the New Zealand Agricultural and Marketing Research and Development Trust (AGMARDT) Grant A17022
文摘The potato psyllid Bactericera cockerelli(Hemiptera:Triozidae)has recently emerged as a serious pest of potatoes and other solanaceous crops.It causes direct feeding damage and also vectors Candidatus Liberibacter solanaceaerum(Lso),a pathogen that causes zebra chip disease in potatoes and which potentially costs growers millions of dollars each year.Such producers rely on frequent sprays of pesticides for psyllid control but the results are unsatisfactory and there are negative side effects.The psyllid has spread beyond its native range in southwest US and northern Mexico to Canada,El Salvador,Honduras,Guatemala and Nicaragua via medium to long range dispersal flights perhaps aided by wind currents,and through anthropogenic means.It was accidentally introduced into New Zealand in 2006 and most recently Australia,most likely through the importation of infested plant material.This review summarizes information from studies on the biology,impact and management of B.cockerelli,and highlights the imminent risk of this insect and its associated pathogen invading China,the world’s largest producer of fresh potatoes.Development of risk maps leading to increased surveillance,could prevent or delay an incursion and facilitate early detection or eradication should this occur.Long-term management with Lso-tolerant potato cultivars and psyllid control using the parasitic wasp Tamarixia triozae and other natural enemies should be pursued,rather than depending on synthetic pesticides.
基金supported by the New Zealand Institute for Plant and Food Research Limited Internal Core fundingthe Plant Biosecurity Cooperative Research Centre (Australia) (CRC2079)the Sustainable Farming Fund (New Zealand, 09/143, 12/058, and 404861)Potatoes New Zealand Inc.
文摘The psyllid Bactericera cockerelli was first reported in New Zealand in 2006 and spread quickly throughout all potato growing regions.In 2009,B.cockerelli was associated with the plant pathogenic bacterium Candidatus Liberibacter solanacearum,the putative causal agent of zebra chip disease in potato.Both the psyllid and the bacterium have non-crop host plants which can serve as reservoirs when the crop is not available.Growers apply different management strategies that fit integrated pest management programmes to manage B.cockerelli and subsequently lower incidence of zebra chip disease in potato crops.Despite best management efforts,complete control of B.cockerelli and zero incidence of zebra chip disease are not achievable at the current time.
文摘Tomato crops(Physalis ixocarpa Brot.)are produced in almost all Mexico,part of the United States and Central America.Recently the tomato production has suffered economic losses of 70%to 80%due the presence of yellowing and floral abortion,whose causal agent has been attributed to the presence of phytoplasma;an insect vector of these phytoplasma is Bactericera cockerrelli Sulc.Alternative control of this psyllid has lacked effectiveness because their spatial distribution is unknown within tomato plots.This study aimed to determine the spatial distribution of populations of nymphs of B.cockerelli in four tomato plots,the determination of the spatial distribution was performed by means of geostatistics.The experimental semivariogram was determined to adjust to a theoretical model(spherical,exponential or Gaussian)through the program Variowin 2.2,the adjustment was validated with the method of cross-validation and aggregation maps of the pest were obtained through Kriging with Surfer 9.0 program.The short-term time-space stability of the pest was determined through the tests Crámer-von Mises.The results showed that populations of nymphs of B.cockerelli have a distribution of aggregate type,which was corroborated by density maps.Infestations are not present in 100%of the surface of the experimental plots,which helps to direct control measures on specific areas of infestation.
基金the AgriLife Research Insect Vector Diseases Grant Programthe USDA-AFRI grant(2014-67013-21781)+1 种基金USDA-APHIS(AP18PPQS&T00C235)China Scholarship Council.
文摘The potato/tomato psyllid Bactericera cockerelli causes serious damage to several solanaceous crops by direct feeding and vectoring Candidatus Liberibacter solanacearum,a bacterial pathogen.Electron beam(eBeam)irradiation is an environmentally friendly,chemical-free alternative method that is increasing in use for disinfestation of insect pests.We hypothesize that this irradiation technology will have detrimental effects on potato psyllid and thus impede its disease vectoring.To this end,we explored the effects of eBeam treatment ranging from 50 to 500 Gy on survival,development and reproduction of this pest.Impact on psyllids was apparently dose-dependent.When irradiated at 350 Gy,eggs could not hatch,1st instar nymphs failed to emerge,and although a small portion of irradiated 5th instar nymphs survived,the emerged adults were mostly deformed.Abnormality in eclosed adults suggests harmful effects of eBeam on metamorphosis.Reproduction was seriously impaired when female psyllids were exposed to eBeam at the 5th instar nymphal or young adult stage,presumably due to inability to form oocytes.In addition,reciprocal crosses between irradiated and untreated psyllids indicated that female psyllids were more radiosensitive than males to eBeam.Taken together,these findings indicate that eBeam negatively impacted potato psyllid development and reproduction,which would inevitably compromise its disease transmission capacity.A dose of 350 Gy can be considered as a reference dose for effective control of potato psyllids.
文摘The impacts of potato psyllid （Bactericera cockerelli） feeding on potato foliage on the free amino acids （FAAs） composition in potato leaf and tubers were determined under greenhouse conditions. The free amino acids in plant extracts were separated by high-performance liquid chromatography, and in both leaf and tuber samples, at least 17 FAAs were detected. Psyllid feeding significantly changed the levels of several FAAs in both leaf and tuber samples. The concentration of leucine increased 1.5-fold, whereas that of serine and proline increased 2- and 3-fold, respectively. In contrast, the concentrations ofglutamic acid, aspartic acid and lyscine were significantly reduced by 42.0%, 52.1% and 27.5%, respectively. There were also significant changes in the levels of FAAs in the Zebra chip （ZC） infected tubers compared with the healthy tubers, and the levels of six of the FAAs increased, and the levels of nine of the FAAs decreased. The results from this study indicate that potato psyllid causes major changes in free amino acid composition of plant tissues, and this change in plant metabolism may contribute to the plant stress as indicated by increased levels of proline in the leaves and hence promoting the development of plant diseases such as ZC disease.
