Research progress on Bemisia tabaci(Gennadius) biotypes
烟粉虱生物型研究进展

The whitefly Bemisia tabaci(Genn.) is an important agricultural pest that feeds in the phloem.It also is the most important vector of several plant virus genera,worldwide.B.tabaci is considered by most to represent a species complex,which comprises a large number of genetically and biologically variable populations,and well-studied biological types.The B biotype is a particularly aggressive B.tabaci variant that has been established in many of the worlds cropping systems including China.It has become established in many locations worldwide,beginning in about 1988.Since then,it has been of considerable concern as a pest and virus vector in the Americas and Caribbean region,and other countries having subtropical climates.In China B.tabaci became an important agricultural pest and virus vector in the late 1990s,and its establishment in China was reported for the first time in 2002.The B biotype is now widespread in a number of provinces in China where vegetables,cotton,and ornamentals are produced.Recent studies have demonstrated that there are several major B.tabaci haplotypes in China including those thought to be indigenous,and at least one exotic biotype(e.g.the B biotype).In China and elsewhere,it has become realized that the B.tabaci populations are polymorphic,cryptic species that can upsurge without warning and cause great damage to crop and ornamental species.It is important to understand the biology differences between biotypes of B.tabaci in order to devise effective control practices.Characteristics that are known to vary amongst distinct biotypes of B.tabaci include host range,virus transmission competency,fecundity,insecticide resistance,all of which can feasibly influence management strategies.Molecular markers have been used to distinguish biotypes and to analyze genetic differentiation.The mitochondrial cytochrome oxidase I(mt COI) gene is a highly informative coding sequence for differentiating variants of the B.tabaci complex.The mtCOI was herein used as a marker to identify and determine the distribution of haplotypes or biotypes in China.