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Laboratory Test on the Infectivity of Entomopathogenic Nematode, Steinemema feltiae Beijing, to Rice Weevil, Echinonmus squameus, overwintered in Wheat Field
Chen Junwei,Zhang Zhetao,Jiang Jinwei,Wang Shiming,Guo Yujie,Wang Nianying
1996, 10(2):
125-128 .
Rice weevil, Echinonmus squameus, is becoming one of major rice insect pest in Yellow valley in Henan province due to the increase of rice cultivating area, new variety deposition as well cropping system changes. The diapause of the weevil occurs at matured larva stage in the rice stubble left in the following winter wheat field. Laboratory test showed that the entomopathogenic nematode, Steinemema feltiae Beijing, has a quite high pathogenicity on the over-wintered weevil larvae and resulted in 96. 7% of the mortality. The reinfection by the killed larva was evaluated and the mortality of re-infected larvae might reach 69% and 83% after 7 and 14 days, respectively. The killed larvae increased from 46.8% to 86.0% with rising the dosage of the nematodes from 100,000/m2 to 150,000/m2. The weevil larva density also significantly influenced the control effectiveness. A better control may be obtained using less nematodes at low larva density and more nematodes at higher larva density.
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