瓦螨微生物防治的不良效果(英文)

We report six different field trials testing the efficacy of Metarhizium anisopliae,an entomopathogenic fungus,against varroa mites in honey bee hives.Varroa mites are parasitic on honey bees and cause serious damage to Apis mellifera colonies.Several control methods are available for varroa mites,none are very effective,so new,more effective methods are being sought.Varroa has previously been shown to be highly susceptible to M.anisopliae infections,and in our first two field trials,we found some efficacy from spore applications.However,in subsequent field trials,we were not able to obtain any varroa control,despite attempting several different application methods,two different strains of the fungus,and testing in different climates and during different phenological states of the honey bee colony.We conclude that microbial control of varroa using fungi is not likely to be effective unless some way is found to prolong the survival of the spores(or other infective units)in the hive environment.

New insights into the systematics of Entomobryoidea(Collembola: Entomobryomorpha): first instar chaetotaxy, homology and classification

The largest superfamily Entomobryoidea is one of the key groups in Collembola.However,incorrect recognition of chaetotaxic homology within Entomobryoidea severely impedes the accurate species comparison of adults and phylogenetic reconstruction.Traditional classification of the superfamily at suprageneric level is disputable in the light of recent advances.Transformational homology of tergal chaetotaxy was traced and revised based on 38 species of first instar and partial early instars.Morphological phylogenetic reconstructions were reconstructed mainly relying on first instar characters using both parsimony and likelihoodbased algorithms.Outgroup selection and several rogue taxa impacted on resolution and support of otherwise well-supported clades.Integrating published molecular phylogeny,a revised classification of three families and nine subfamilies was presented:Orchesellidae,Entomobryidae and Paronellidae.Orchesellidae includes all basal taxa having a short fourth abdominal segment.Cyphoderidae and Microfalculidae taxa were sunk into Paronellidae.New Paronellidae was divided into two subfamilies:Paronellinae(Paronellini+Cyphoderini+Bromacanthini)and Salininae(Cremastocephalini+Callyntrurini).Microfalculidae(Microfalcula)was closer to Salina and Akabosia and thus transferred into Cremastocephalini.This study erected a new classification framework for Entomobryoidea based upon comprehensive phylogenies.Chaetotaxic homologization across a wide range provided a standardized,comparable,powerful tool for taxonomy.

Antagonistic interaction between male-killing and cytoplasmic incompatibility induced by Cardinium and Wolbachia in the whitefly,Bemisia tabaci

Cardinium and Wolbachia are maternally inherited bacterial symbionts of arthropods that can manipulate host reproduction by increasing the fitness of infected females.Here,we report that Cardinium and Wolbachia coinfection induced male-killing and cytoplasmic incompatibility(CI)when they coexisted in a cryptic species of whitefly,Bemisia tabaci Asia II7.Cardinium and Wolbachia symbionts were either singly or simul-taneously localized in the bacteriocytes placed in the abdomen of B.tabaci nymphs and adults.Cardinium-Wolbachia coinfection induced male-killing and resulted in a higher female sex ratio in the intraspecific amphigenetic progeny of Asia II7 IcwH and IcwL lines;interestingly,male-illing induction was enhanced with increased Cardinium titer.Moreover,single infection of Wolbachia induced partial CI in the Asia II7 Iw line and resulted in reduced fecundity,higher embryonic mortality,and lower female sex ratio.The uninfected Asia II7 Iu line had significantly higher fecundity,lower embryonic and nymphal mortalities,and a lower level of CI than both the Wolbachia infected Asia II7 Iw line and the Cardinium--Wolbachia-coinfected Asia II7 IcwH line.Our findings indicate that Cardinium-Wolbachia coinfection induced male-killing,which may have had antag-onistic effects on Wolbachia-induced CI in the Asia II7 whiteflies.For the first time,our study revealed that B.tabaci Asia II7 reproduction is co-manipulated by Cardinium and Wolbachia endosymbionts.

Huanglongbing:An overview of a complex pathosystem ravaging the world's citrus

Citrus huanglongbing（HLB） has become a major disease and limiting factor of production in citrus areas that have become infected. The destruction to the affected citrus industries has resulted in a tremendous increase to support research that in return has resulted in significant information on both applied and basic knowledge concerning this important disease to the global citrus industry. Recent research indicates the relationship between citrus and the causal agent of HLB is shaped by multiple elements, in which host defense responses may also play an important role. This review is intended to provide an overview of the importance of HLB to a wider audience of plant biologists. Recent advances on host-pathogen interactions, population genetics and vectoring of the causal agent are discussed.