• Korean journal of applied entomology
• /
• v.58 no.4
• /
• pp.363-380
• /
• 2019

Previous studies on the host plant range of Metcalfa pruinosa were conducted without distinguishing between its stages of development. In this study, we investigated host plants by studying the nymph and adult development stages of M. pruinosa. M. pruinosa nymphs were found on host plants that belong to 78 families and 227 species, and, to the best of our knowledge, host plants that belong to 27 families and 38 species have been reported for the first time. The host plants were divided into woody and herbaceous at the nymph stage of M. pruinosa, and the nymphs were found in 110 herbaceous and 117 woody species. M. pruinosa adults were found on host plants that belong to 87 families and 233 species, and, host plants that belong to 26 families and 36 species have been reported for the first time. The host plants were divided into woody and herbaceous at the adult stage of M. pruinosa, and the adults were found in 105 herbaceous and 128 woody species. Therefore, the total domestic host plant of M. pruinosa was 98 families 345 species. The nymph and adult in preoviposition stage prefer Helianthus annuus and the adult in oviposition stage prefer Persicaria tinctoria and Rosa rugosa.

• Korean Journal of Environmental Biology
• /
• v.40 no.4
• /
• pp.423-432
• /
• 2022

The mass-rearing system for Neodryinus typhlocybae as a biological control agent of Metcalfa pruinosa was established. Depending on the density of host nymphs and plants, the average number of cocoons produced by the parasitoids was 5-8 and 70-150 cocoons per leaf and sapling of mulberry, respectively. There is a significant difference in cocoon length between females (6.10-6.46mm) and males (4.20-4.62mm). Sex determination of cocoons before emergence will be helpful for efficiently releasing this parasitoid in fields. The parasitic rate of N. typhlocybae at the semi-field condition was on average 13-17%. The release number of this parasitoid did not affect parasitism. Nevertheless, the population growth rate of M. pruinosa was reduced by increasing the release number of N. typhlocybae. The parasitoid offspring's sex and bivoltine were influenced by the host age. On young host nymphs, the bivoltine portion of parasitoid increased. When parasitized on 4^th or 5^th nymphs, the offspring's female ratio of N. typhlocybae increased. This result may be useful for potentially controlling mass rearing production of parasitoid.

• Korean journal of applied entomology
• /
• v.58 no.4
• /
• pp.291-297
• /
• 2019

Since Metcalfa pruinosa was first reported in Koera, it has continually caused damage to sweet persimmon orchard in southern part of Korea. Metcafa pruinosa exist not only in farmland but also in forest areas, and are difficult to control due to the influx of individuals from near forest. M. pruinosa has been occurred in orchard and its surroundings because of various host range. Thus, it has been difficult to decide spatial range and control time for efficient management. In this study, occurrence and dispersal pattern of M. pruinosa in persimmon orchard were surveyed using clear sticky traps, and spatial patterns were analyzed with SADIE(Spatial Analysis by Distance IndicEs), based on location information at sticky traps. Spatial association between survey time was also analyzed to identify when the spatial pattern changed. In sweet persimmon orchard, M. pruinosa mainly dispersed in mid to late May, when the first instar hatches, and in August, emerging season of adult. The first instar nymphs hatched in mid-May were randomly distributed in orchard, but distribution was changed to aggregative pattern after dispersed surroundings of orchard. Adults showed random distribution pattern after immigration to orchard again. These tendency was also observed in density change at orchard and its surroundings, and matched to actual density of M. pruinosa in sweet persimmon trees.

• Korean journal of applied entomology
• /
• v.58 no.4
• /
• pp.281-282
• /
• 2019

We have developed a composition containing three kinds of plant extracts (Deris, Citronella, and Cinnamon) and supplements (xanthan gum and silicone-based compounds) having high control effects on Metcalfa pruinosa. This composition had more than 90% of the nymph bug control effect in the ginseng plantation. In addition, since the insecticidal rate is high for other absorptive pests, it is considered that it can be used as a countermeasure against the implementation of the PLS (positive list system).

• Korean journal of applied entomology
• /
• v.57 no.4
• /
• pp.297-302
• /
• 2018

We surveyed branches of acacia trees distributed nationally in Korea to establish a common survey method that can be used by investigators to monitor for over-wintering Metcalfa pruinosa eggs. A total of 189 samples was examined, and the number of eggs on the surfaces of the branches, bases of thorns and bases of twigs was recored. When including samples in which no eggs were found at all investigation sites, none of the data followed the normal distribution. However, when samples in which no eggs were found at all sites were exclued, the density of eggs investigated at the thorn bases and twig bases followed the normal distribution. When the density of eggs was sorted based on the thickness of the branches on which they were found, these data did not follow the normal distribution. The density of M. pruinosa eggs at the thorn bases and twig bases was significantly higher than that on the branch surfaces, but there was no significant difference among branches of different thicknesses. Therefore, monitoring for M. pruinosa eggs at the thorn bases and twig bases of the nationally distributed acacia tree, irrespective of the thickness of the branches, will be able to increase the precision with which the density of this insect's eggs could be estimated. It is thus expected that this method will contribute to developing methods to better characterize the distribution and predict the occurrence of this.

• Korean journal of applied entomology
• /
• v.59 no.4
• /
• pp.427-432
• /
• 2020

The ability of sunflower, bean, green perilla, and sesame to attract Metcalfa pruinosa was tested in both laboratory and field conditions. In the laboratory experiment, sunflowers showed the highest attractiveness to M. pruinosa nymphs and adults. These results were the same as those in the field experiment. Sunflowers showed the highest attractiveness among the four candidates as a trap plant for M. pruinosa, with comparable average attractiveness values for nymphs and adults to those in the laboratory. Young beans also showed high attractiveness to M. pruinosa, albeit lower than those of sunflowers. However, the attractiveness of mature beans was low. Sunflowers consistently (P < 0.05) showed significantly higher attractiveness than that of the other three plants, regardless of plant age. Thus, sunflowers would serve as a good trap plant for both the nymphs and adults of M. pruinosa.

• The Korean Journal of Pesticide Science
• /
• v.17 no.4
• /
• pp.419-427
• /
• 2013

The insecticidal activity of 124 plant essential oils and control efficacy of six experimental spray formulations (SF) containing 0.25, 0.5, 1, 2.5, 5, and 10% of the selected oils was examined against both nymph and adult of the citrus flatid planthopper, Metcalfa pruinosa using direct contact applications (leaf dipping and spray). Reponses varied according to dose (1,000 and 500 mg/L). When exposed at 1,000 mg/L for 24 h using leaf dipping assay, 19 essential oils showed strong mortality (100%) among 124 essential oils screened. At 500 mg/L, 100% mortality was observed in cinnamon technical, cinnamon green leaf, cinnamon #500, cassia tree, citronella java and pennyroyal followed by origanum, thyme white, grapefruit, savory, fennel sweet, aniseed and cinnamon bark showed considerable mortality (93.3-80%) against nymphs of M. pruinosa. The moderate mortality (73.3-60%) was found in thyme red, tagetes, calamus, lemoneucalptus and geranium. Oils applied as SF-10% sprays provided 100 % mortality against adult M. pruinosa. One hundred mortalities were achieved in cinnamon technical at >SF-0.5 formulation, in cinnamon #500, cinnamon green leaf and penny royal at >SF-2.5. To reduce the level of highly toxic synthetic insecticides in the agricultural environment, the active essential oils as potential larvicides could be provided as an alternative to control M. pruinosa populations.

• Journal of Applied Biological Chemistry
• /
• v.61 no.3
• /
• pp.291-295
• /
• 2018

Metcalfa pruinosa is a pest causing widespread problems to many crops in Korea. This pest infects fruit crops especially, persimmon and grapes. We tested the possibility of M. pruinosa management using essential oils of Alpina galangal and methylcinnamate which were extracted from A. galangal by steam distillation method. The use of essential oil showed a mortality rate of 10.0 and 23.3% for adults and nymphs, respectively. While the use of methylcinnamate resulted to a mortality rate of 40.0% in adults and 36.6% in nymphs. For its repellent effect, it showed an avoidance rate of 50.0 and 63.3% for adult and nymph respectively. Considering these two results, the extract of A. galangal are shown to have some synergic effect for pest control. The result of this study showed a possibility of M. pruinosa control using essential oil and methylcinnamate from A. galangal.

• Korean journal of applied entomology
• /
• v.54 no.4
• /
• pp.375-382
• /
• 2015

The insecticidal activity of the constituents of cinnamon essential oils and structurally related compounds against both the nymphs and adults of the citrus flatid planthopper Metcalfa pruinosa was examined using a direct-contact application. The toxicity of the cinnamon oil constituents and 21 (E)-cinnamaldehyde related compounds regarding the nymphs of M. pruinosa was evaluated using a leaf-dipping bioassay. Based on 24 h $LC_{50}$ values, hydro-cinnamic acid ($1.55mg/cm^2$) is the most toxic compound, followed by geranic acid ($1.59mg/cm^2$). The $LC_{50}$ values of 11 of the compounds including cinnamaldehyde are between $1.60mg/cm^2$ and $4.94mg/cm^2$. Low toxicities and no toxicity were observed with the other 15 ($5.24mg/cm^2$ to $13.47mg/cm^2$) and two compounds, respectively. Also, the toxicities of the cinnamon oil constituents and 21 cinnamaldehyde related compounds regarding the M. pruinosa adults were evaluated using a direct-spray method. The toxicity of eugenol (10.81 mg) is the most toxic compound for the adults of M. pruinosa, followed by geranic acid (30.68 mg). The $LC_{50}$ values of nine of the compounds including cinnamaldehyde are between 59.16 mg and 96.70 mg. Low toxicities and no toxicity were observed with the other 15 (105.44 mg to 255.76 mg) and three compounds, respectively. The spray formulations that comprise cinnamon bark and cinnamon green leaf oils resulted in 82.3% and 82.9% mortalities, respectively, toward the M. pruinosa adults in a ginseng field. Global efforts to reduce the level of highly toxic synthetic insecticides in agricultural environments justify further studies on cinnamon oils to ascertain whether the corresponding active principles can act as insecticides, when they are applied as a direct spray with contact action, for the control of M. pruinosa populations.

• Life and Agrochemicals
• /
• s.267
• /
• pp.30-33
• /
• 2011