Sporamin-mediated resistance to beet cyst nematodes (Heterodera schachtii Schm.) is dependent on trypsin inhibitory activity in sugar beet (Beta vulgaris L.) hairy roots.
Sporamin, a sweet potato tuberous storage protein, is a Kunitz-type trypsin inhibitor. Its capability of conferring insect-resistance on transgenic tobacco and cauliflower has been confirmed. To test its potential as an anti-feedant for the beet cyst nematode (Heterodera schachtii Schm.), the sporamin gene SpTI-1 was introduced into sugar beet (Beta vulgaris L.) by Agrobacterium rhizogenes-mediated transformation. Twelve different hairy root clones expressing sporamin were selected for studying nematode development. Of these, 8 hairy root clones were found to show significant efficiency in inhibiting the growth and development of the female nematodes whereas 4 root clones did not show any inhibitory effects even though the SpTI-1 gene was regularly expressed in all of the tested hairy roots as revealed by northern and western analyses. Inhibition of nematode development correlated with trypsin inhibitor activity but not with the amount of sporamin expressed in hairy roots. These data demonstrate that the trypsin inhibitor activity is the critical factor for inhibiting growth and development of cyst nematodes in sugar beet hairy roots expressing the sporamin gene. Hence, the sweet potato sporamin can be used as a new and effective anti-feedant for controlling cyst nematodes offering an alternative strategy for establishing nematode resistance in crops.
Cai
Daguang
D
Institute of Crop Science and Plant Breeding, Christian-Albrechts University Kiel, Olshausenstrasse 40, 24098 Kiel, Germany.
Thurau
Tim
T
Tian
Yanyan
Y
Lange
Tina
T
Yeh
Kai-Wun
KW
Jung
Christian
C
D000818:Animals; D027461:Beta vulgaris / Q000235:genetics* / Q000469:parasitology; D015152:Blotting, Northern; D015139:Blotting, Southern; D015153:Blotting, Western; D018744:DNA, Plant / Q000235:genetics; D005260:Female; D018628:Gene Dosage; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D007113:Immunity, Innate / Q000235:genetics; D008297:Male; D009348:Nematoda / Q000254:growth & development*; D010455:Peptides; D010935:Plant Diseases / Q000235:genetics / Q000469:parasitology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018517:Plant Roots / Q000235:genetics / Q000469:parasitology; D030821:Plants, Genetically Modified; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D014361:Trypsin Inhibitors / Q000235:genetics / Q000378:metabolism / Q000502:physiology
D018744:DNA, Plant; C053865:Kunitz-type protease inhibitor, plant; D010455:Peptides; D010940:Plant Proteins; D018749:RNA, Plant; D014361:Trypsin Inhibitors; C067142:sporamin protein, Ipomoea batatas