Evaluation of the resistance of transgenic potato plants expressing various levels of Cry3A against the Colorado potato beetle (Leptinotarsa decemlineata Say) in the laboratory and field.
BACKGROUND
The Colorado potato beetle (CPB), Leptinotarsa decemlineata Say, is a destructive pest. The CPB is a quarantine pest in China, but has now invaded the Xinjiang Uygur Autonomous Region and is continuing to spread eastwards. To control the damage and overspreading, transgenic potato plants expressing Cry3A toxin were developed, and their resistance to CPB was evaluated by bioassays in the laboratory and field in 2009, 2010 and 2011.


RESULTS
The insect resistance of the high-dose (HD) transgenic lines was significantly greater than the middle-dose (MD) and low-dose (LD) transgenic lines regarding leaf consumption, biomass accumulation and mortality. The HD and MD transgenic lines showed 100% mortality when inoculated with first- and second-instar larvae; however, the LD transgenic lines showed about 50% mortality. The HD transgenic lines exhibited a significantly higher yield than the MD and LD transgenic lines owing to their high CPB resistance.


CONCLUSIONS
Commercially available transgenic potato plants with above 0.1% Cry3A of total soluble protein and NT control refugia could control damage, delay adaptation and halt dispersion eastwards. The two HD transgenic lines developed in this study, PAH1 and PAH2, are ideal for use as cultivars or germplasm to breed new cultivars.
State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
Zhaoxu
Z
Zhou
Jinhuan
J
Pang
Wenchao
W
Guo
Naiqin
N
Zhong
Yingchuan
Y
Tian
Guixian
G
Xia
Jiahe
J
Wu
D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D061046:Biological Control Agents; D001517:Coleoptera; D004731:Endotoxins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005247:Feeding Behavior; D006460:Hemolysin Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010571:Pest Control / Q000379:methods; D030821:Plants, Genetically Modified / Q000378:metabolism*; D011198:Solanum tuberosum / Q000235:genetics* / Q000378:metabolism
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D061046:Biological Control Agents; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis