• Korean journal of applied entomology
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• v.42 no.2
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• pp.159-163
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• 2003

This experiment was conducted to investigate pathogenicity of Spodoptera litura nucleopolyhedrovirus (SINPV) with different temperatures to mass production. In laboratory, LC$_{50}$ values of SINPV were 5.534$\times$10$^3$ PIBs/ml and 4.l0$\times$10$^2$PIBs/ml in 1st instar larvae at 2$0^{\circ}C$ and 28$^{\circ}C$, respectively, but those were increased at 32$^{\circ}C$. LC$_{50}$ at 3rd and 5th instar larvae were showed the lowest value at 28$^{\circ}C$. LT$_{50}$ values of SINPV in 1.0$\times$10$^{5.7}$ PIBs/ml were determined at various temperature conditions (20-32$^{\circ}C$). The result showed that treatments at 28$^{\circ}C$ and 32$^{\circ}C$ shortened LT$_{50}$ values, but treatments at 2$0^{\circ}C$ and 24$^{\circ}C$ was relatively longer. Also LT$_{50}$ values was shortened in high concentration and young larva. LT$_{50}$ values are dependent on the temperature, viral concentration and larval instar.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.55-60
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• 2004

This experiment was conducted to improve activity of Spodoptera litura Nucleopoly-hedrovirus (SINPV) combined with organic and functional matters. In combination of SINPV mixed with organic matters, LT$_{50}$ values of SINPV 1.0${\times}$10$^{5}$ PIBs/$m\ell$ combined with boric acid of 2,000 ppm were 4.5 days. It was 1.5 days shorter than SINPV 1.0${\times}$10$^{5}$ PIBs/$m\ell$ alone. The body weight of larva infected with SINPV 1.0${\times}$10$^{5}$ PIBs/$m\ell$ combined with boric acid of 2,000ppm was not increased, and S. litura was completely dead in 7 days after treatment. It suggested that addition of boric acid in SINPV application enhanced the pathogenicity against S. litura larvae. In laboratory experiment of combination of SINPV with functional matters, LT$_{50}$values of SINPV 1.0${\times}$10$^4$ PIBs/$m\ell$ alone were 7.3 days, but those of SINPV 1.0${\times}$10$^4$ PIBs/$m\ell$ with electrolyzed oxidizing water, pyroligneous liquor or kitosan were 10.4, 9.3 and 11.2 days, respectively. Functional matter could be suppressed the insecticidal activity of SINPV

• Korean journal of applied entomology
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• v.42 no.2
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• pp.153-157
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• 2003

This experiment was conducted to investigate control effect of Spodoptera litura using nucleopolyhedrovirus in chrysanthemum seedlings of open field and plastic house. Values of LT$_{50}$ of treatment 1.0$\times$10$^{6.8}$ PIBs/ml were 6.2-5.1 days in open field and 6.9-5.4 days in plastic house. Values of LT$_{50}$ and LT$_{95}$ were shorter in open field than in plastic house. Cumulative mortality was 100% in 1.0$\times$10$^{7.8}$ PIBs/ml and also higher in open field than in plastic house. In chrysanthemum field, organic synthetic insecticide (endosulfan EC) killed S. litura larvae in 2 days after application. Motality of S. litura larva inoculated with S. litura nucleopolyhedrovirus (SINPV) 1.0$\times$10$^{6.8}$ PIBs/ml was found out from 4 days after application and maintained during 14 days. Protection values of with SINPV 1.0$\times$10$^{8}$ PIBs/ml after 16 days were 94.0% and 89.4% in open field and plastic house, respectively, and those of endosulfan 350 ppm were 91.4% and 88.6%, respectively.