• Mycobiology
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• v.45 no.3
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• pp.192-198
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• 2017

The green peach aphid (Myzus persicae), a plant pest, and gray mold disease, caused by Botrytis cinerea, affect vegetables and fruit crops all over the world. To control this aphid and mold, farmers typically rely on the use of chemical insecticides or fungicides. However, intensive use of these chemicals over many years has led to the development of resistance. To overcome this problem, there is a need to develop alternative control methods to suppress populations of this plant pest and pathogen. Recently, potential roles have been demonstrated for entomopathogenic fungi in endophytism, phytopathogen antagonism, plant growth promotion, and rhizosphere colonization. Here, the antifungal activities of selected fungi with high virulence against green peach aphids were tested to explore their potential for the dual control of B. cinerea and M. persicae. Antifungal activities against B. cinerea were evaluated by dual culture assays using both aerial conidia and cultural filtrates of entomopathogenic fungi. Two fungal isolates, Beauveria bassiana SD15 and Metarhizium anisopliae SD3, were identified as having both virulence against aphids and antifungal activity. The virulence of these isolates against aphids was further tested using cultural filtrates, blastospores, and aerial conidia. The most virulence was observed in the simultaneous treatment with blastospores and cultural filtrate. These results suggest that the two fungal isolates selected in this study could be used effectively for the dual control of green peach aphids and gray mold for crop protection.

• 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.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.596-602
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• 2012

Infestations of Aphis gossypii per leaf in greenhouse cultivation of cucumbers were investigated to develop binomial sampling plans. An empirical $P_T-m$ model, $ln(m)={\alpha}+{\beta}ln[-ln(1-P_T)]$, was used to evaluate relationship between the proportion of infested leaves with ${\leq}$ T aphids per leaf ($P_T$) and mean aphid density (m). Tally thresholds (T) were set to 1, 3, 5, 7, and 9 aphids per leaf to find appropriate T in greenhouse cultivation of cucumbers. Increasing sample size had little effect on the precision of the binomial sampling plan. However, the precision increased with tally threshold. The binomial model with T = 5 provided appropriate predictions of the mean densities of A. gossypii in the greenhouse cultivation of cucumbers. Using a binomial model with T = 5 (sample size = 200), a wide range of densities (1.2 - 222.8 aphids per leaf) could be estimated with precision levels of 0.346 - 0.380 for $P_T$ values between 0.15 and 0.96. Binomial models were validated at T = 5 and 7 using 12 independent data sets. Both binomial models were robust and adequately described aphid densities; most of the independent sampling data fell within 95% confidence intervals around the prediction model.

• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.205-208
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• 1974

This survey was carried out in order to find out population density of aphid at the alpine area. Thetraps were set from May 1 to October 31 in 1973. The summarized results are as follows; 1. About 37 species of aphids were trapped, including 4 species of potatao virus vectors. 2. Of these, dominant species are Aphis gossypii Koch, Aphis lerodendri Matsumura, and Lipahis erysimi Kaltenbaeh. The $67\%$ of 3, dominant species consisted of the trapped total aphids. 3. The potato virus vectors are Myzus persicae Sulzer, Aulacorhum solani Kaltenbach, Lipaphis erysimi Kaltenbaeh and Aphis gossypii Glover. 4. Tile number of aphids and vectors at the alpine area is considerably lower than that at the level land. 5. The peak of the flying aphid occurrence is shown in the latter part of September.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.248-253
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• 2001

These studies were carried out to examine the developmental process of galls caused by aphids in Rhus gavanica and the effects of indole-3-acetic acid (IAA) and ${\alpha}$-naphthalene acetic acid (NAA) on the tannin accumulation in the callus induced from that galls. The results are follows. The development of fist-shaped galls has begun at the beginning of June earlier than the case of finger-shaped galls, and also, the growth of fist-shaped galls has last to September longer than the period of finger-shaped galls. These results indicate that the life cycle and feeding activity of the aphids inhabited in fist-shaped galls were longer and mire active than the case of the aphids inhabited in finger-shaped galls. Tannin contents of fist-shaped galls revealed about 60${\sim}70%$ of total dry weights during the whole growth periods, however, the contents in finger-shaped galls were under 10% at the maximum value. These facts mean that finger-shaped galls seem to be as a habitat of aphids rather than as a major source of tannin such as fist-shaped galls. The growth of callus induced from fist-shaped galls was the most effective in the plot of $10^{-5}$ mole IAA, but the tannin accumulation in callus growth was not even caused in any plots of IAA treatments as wells as in any NAA plots. These results considered that the tannin accumulation in fist-shaped galls may be caused only in specific relation between host plant and life cycle of aphids.

• Korean journal of applied entomology
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• v.23 no.1 s.58
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• pp.28-36
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• 1984

The relationship between ratio of virus diseases and the population of aphid vectors was studied by planting radishes(Rophanus sativus L. var. Chungsu gungjung) every 10 days and collecting aphids from April to November at Jeonju, Korea in 1982. Alate aphids were collected with yellow pan traps and virus infection ratios were checked with symptoms. The populations of flying aphids showed two peaks, one in the late May and one in the middle October in Jeonju and the population of aphid vectors also showed the same inclination. Of aphid vectors, Myzus persicae, Lipaphis erysimi, Brevicoryne brassicae, and Aphisgossypii were trapped and their percentages to total trapped aphids were $62.82\%(39,260/62,499)$ M. persicae was the most prevalent species and its percentages to aphid vectors were $82.53\%(32,401/39,260)$. High and sudden increase in virus infection ratio was found in spring while the trend in autumn was slow and low. A correlation coefficient between the population of virus vector aphid and virus infection ratio was $r=0.7414^*(\hat{Y}=8.1444+0.0551X)$ in spring and $r=0.9117^{**}(\hat{Y}=10.2590+0.463X)$ in autumn. The symptoms of radish virus diseases appeared approximately 15 days after virus vector aphids had attacked. Virus infection ratios were higher on plots where virus infected plants were reserved than on plots where they were removed.

• Korean journal of applied entomology
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• v.13 no.1 s.18
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• pp.25-31
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• 1974

This survey was aimed to accumulate basic data of aphid population at the Horticultural Experiment Station at Suweon. The yellow pan traps were setted at five locations (Fig.1.), and ran from May 1 to October 31. 1970. About one hundred and twenty species of aphids were trapped, including 24 species of plant vims vectors. Of these, dominant species were as follows: (Asterisk shows virus vector) Aphid species No. of catches * Aphis spiraecola PATCH 2,635, * Aphis craccivora KOCH 2,377, * Myzus persicae SULXER 2,111, Capitophorus hippophaes javanicus H.R. LAMBERS 2,051, Anoecia fulviabdominalis SASAKI 1,480, * Aphis gossypii GLOVER 867, * Macrosiphum avenae FABRICIUS 859, Cervaphis quercus TAKAHASHI 692, * Lipaphis erysimi KALTENBACH 645, Pleotrichophorus chrysanthemi THEOBALD 489, The above 10 species consisted $76.5\%$ of total catches and the 24 vector species consisted $55.5\%$. The curve of the seasonal occurrence of flying aphids at Horticultural Experiment Station shows bimodal, typical for the temperate region. The total number of trapped aphids at the Station from May to September, 1970, were less than that of average yearly catches at the College of Agriculture from 1967 to 1970. Thi, low numbers at Horticultural Experiment Station may attribute to the frequent spraying of insecticides from Spring to Summer on growing crops there. But the aphids population increase suddenly in the middle of October. This might be resulted from cease of insecticide applications and migration of aphids from summer host to winter host plants.

• Bulletin of the Korean Chemical Society
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• v.7 no.2
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• pp.157-158
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• 1986

• Korean journal of applied entomology
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• v.51 no.4
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• pp.397-403
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• 2012

This study compared the Aphelinus varipes and Aphelinus asychis in terms of how they parasitized the cotton aphid, Aphis gossypii and green peach aphid, Myzus persicae. Host-feeding, parasitism, emergence, the proportion of females and development time were all studied at 15, 20, 25 and $30^{\circ}C$ in controlled climate cabinets. When A. gossypii were provided for the two aphid parasitoids, the number of aphids killed by host-feeding for A. varipes (5.4 and 9.7 aphids) at $15^{\circ}C$ and $25^{\circ}C$ was higher than those for A. asychis (2.0 and 2.9 aphids). At $15^{\circ}C$ and $30^{\circ}C$, the parasitized A. gossypii were higher in A. varipes (11.1 and 21 aphids) than in A. asychis (7 and 12.3 aphids). The emergence rate was also significantly different between A. varipes (83.3%) and A. asychis (69.4%). The proportion of females was higher for A. asychis (75.2 and 73.9%) than for A. varipes (19.5 and 48.6%) at $15^{\circ}C$ and $30^{\circ}C$, respectively. No significant differences were found in development time between the two parasitoids. When M. persicae were provided for the two parasitoid species, the host-feeding number and the emergence rate of two parasitoids were not different at all four temperatures. The M. persicae were more highly parasitized by A. varipes (12.1 and 17.1 aphids) than by A. asychis (6.1, 10 aphids) at 20 and $25^{\circ}C$. The proportion of females for A. varipes (65.3 and 90.0%) was higher than that for A. asychis (34.4 and 78.8%) at $15^{\circ}C$ and $25^{\circ}C$. The development time from oviposition to the adult emergence of A. varipes (19.9 d) was significantly longer than that of A. asychis (16.5 d) at $20^{\circ}C$. Development times decreased with increasing temperature for both in two parasitoid species.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.116-117
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• 2003

Aphidicidal activity of Bacillus thurigiensis crystal proteins was recently reported. However, relatively higher dose of crystal protein was needed to kill aphids. In this study, we intended to improve the aphidicidal activity of crystal protein by fusion with coat protein (CP) of potato leafroll virus (PLRV) which is transmitted by aphids. (omitted)