Further Spread of and Domination by Bemisia tabaci (Hemiptera: Aleyrodidae) Biotype Q on Field Crops in China

The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), causes severe crop losses to many crops. The worst of these losses are often associated with the invasion and establishment of biotypes B and Q of this pest. Previous research in 2007 showed that biotype Q occurred with other biotypes in most field populations in China. To determine the current status of the biotype composition in the field, an extensive survey covering mainly eastern parts of China was conducted in 2009. Using polymerase chain reaction primers specific for the mitochondrial cytochrome oxidase I of biotypes B and Q and gene sequencing, we determined the biotypes composition in 61 whitefly populations and their distribution across 19 provinces in China. Our research revealed that only biotypes B and Q have been found in the field in 2009 in China. Among them, biotype Q was dominant in 44 locations (100.0%) and biotype B was dominant in 17 locations (100.0%). The current survey indicates that biotype Q has rapidly displaced biotype B in most locations in China.