• Korean journal of applied entomology
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• v.46 no.2
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• pp.213-219
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• 2007

The development of Schizaphis graminum (Rondani) was studied at various constant temperatures ranging from 15 to $32.5^{\circ}C$, with $65{\pm}5%$ RH, and a photoperiod of 16L:8D. Mortality of the $1_{st}-2_{nd}\;and\;the\;3_{rd}-4_{th}$ stage nymphs were similar at most temperature ranges while at high temperature of $32.5^{\circ}C$, more $3_{rd}-4_{th}$ stage individuals died. The total developmental time ranged from 13.8 days at $15^{\circ}C$ to 4.9 days at $30.0^{\circ}C$ suggesting that the higher the temperature, the faster the development. However, at higher end temperature of $32.5^{\circ}C$ the development took 6.4 days. The lower developmental threshold temperature and effective accumulative temperatures for the total immature stage were $6.8^{\circ}C$ and 105.9 day-degrees, respectively and the nonlinear shape of temperature related development was well described by the modified Sharpe and DeMichele model. The normalized cumulative frequency distributions of developmental period for each life stage were fitted to the three-parameter Weibull function. The attendance of shortened developmental times was apparent with $1_{st}-2_{nd}\;nymph,\;3_{rd}-4_{th}$ nymph, and total nymph stages in descending order. The coefficient of determination $r^2$ ranged between 0.80 and 0.87.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.37-42
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• 2007

To construct a life table and development model Schizaphis graminum (Rondani), its adult longevity and fecundity were studied at various constant temperatures ranging from 15 to $32.5^{\circ}C$, with $65{\pm}5%$ RH, and a photoperiod of 16L:8D. Adult longevity of the greenbug gradually increased with decreasing temperature below $32.5^{\circ}C$. Total fecundity was not significantly different at all temperatures except at $32.5^{\circ}C$. Daily fecundity gradually increased from $25.0^{\circ}C$. It was 3.6 at $27.5^{\circ}C$ and as temperatures either went down or up, it decreased to 1.4 at $15.0^{\circ}C$ and 0.4 at $32.5^{\circ}C$ Net reproduction rate (Ro) was highest with 47.6 at $25.0^{\circ}C$. The intrinsic rate of increase per day $(r_m)$ and the finite rate of increase per day $({\lambda})$ were highest with 0.4 and 1.5 at $30.0^{\circ}C$, respectively and the doubling time (Dt) was shortest with 0.98 at $32.5^{\circ}C$. The mean generation time (T) was 8.41 at $30.0^{\circ}C$.

• Korean journal of applied entomology
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• v.42 no.1
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• pp.81-84
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• 2003

Biological control of aphids using "banker-plants with the parasitoiid, Aphidius colemani Viereck (BPAC)" was carried out on cucumber in greenhouse. The BPAC consisting of barley seedlings infested with Schiraphis graminum (Rondani) enhanced the early establishment of Aphidius colemani in the greenhouse and prolonged the control of Aphis gossypii on May 8, 2001 The BPAC was placed in the greenhouse at transplanting at the rate of 1 per 30 m2 of cucumber. Although good control effect was gained until early August after placing banker plants on May 9, the effect after then because of high temperature. The aphid population on cucumber in control plots reached to a peak on June 26, and decreased because of entomopathogenic fungus for rainy season of July, and increased again to a very high population on August.