• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.413-426
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• 2023

These experiments were conducted for 3 years from 2021 to 2023 to develop a method that can be safely used to prevent the leakage of Golden apple snails (Pomacea canaliculata) from eco-friendly rice plantations. In the southern part of Jeollanam-do, after planting rice, the young golden apple snails placed in the rice field become adults around mid-July and begin spawning. These individuals can overwinter in drains that do not dry out, but individuals hatched after mid-July will not mature enough to overwinter. The size of golden apple snails overwintered in the drainage canal was more than 2.5cm in shell height. Installing a net at the inlet could block 95% of the inflow of snails, and 99% of outflow was blocked by installing an improved water trap and net at the drain. During the mid-drying period and pre-harvest drying period, a water path was created with a power paddy pottery machine. 59.5% of snails were attracted to the waterway, and it took 130 minutes to build the waterway and collect the snails. Based on these results, seasonal paddy management tips for the safe use of giant snails in rice fields were suggested.

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.04a
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• pp.97-97
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• 2019

• Proceedings of the Korean Society of Crop Science Conference
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• 2021.10a
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• pp.44-44
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• 2021

• Korean Journal of Environmental Biology
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• v.33 no.1
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• pp.83-91
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• 2015

This study is measured the change of chlorophyll-${\alpha}$ concentration and phytoplankton density, the grazing rates (GR) and pseudofaeces production (PFP), by grazing of freshwater apple snail, Pomacea canaliculata, to investigated that the snails are able to control of phytoplankton bloom. The experiments are performed to evaluate the GR and PFP at different conditions such as incubation time (0, 2, 4, 6, 8, 10 and 12 hr), shell height (1.0 to 4.0 cm, n=108), snail density (1, 1.5, 2.5, 3.5 and 5 indiv. $L^{-1}$) and food concentration (200, 400, 600, 800 and $1000{\mu}g$ $L^{-1}$). Regarding feeding time, the highest GR (2.5 L. $gAFDW^{-1}h^{-1}$) and PFP (15.3 mg $AFDW^{-1}$) showed at 4 hr after snail stocking, respectively. The snail, smaller than 1.5 cm in body size, showed the highest of GRs (2.54 L. $gAFDW^{-1}h^{-1}$) for the initial period (2 hr of stocking), compared to those greater than 1.5 cm, which showed a stable FR, higher than 0.099 L. $gAFDW^{-1}h^{-1}$. Upon snail density effect, the density of 5 indiv. $L^{-1}$ induced the most effective inhibition on phytoplankton biomass with the highest PFP. On the food concentration, the highest GR (0.54 L. $gAFDW^{-1}h^{-1}$) and PFP (8.5 mg $gAFDW^{-1}$) were induced at the level of $600{\mu}g$ $L^{-1}$, respectively. We checked that it is possible to control of phytoplankton bloom by the grazing of apple snail as well as Reeve. However, it required a through research for the remove of pseudofaeces and 2nd problem by the decomposition of the organic materals.

• Korean Journal of Weed Science
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• v.32 no.3
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• pp.273-279
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• 2012

This experiment was conducted to determine a potential effective biological weed control and/or rice young seedling injury by golden apple snail (Pomacea canaliculata) at wet hill seeded rice field. The rice seeds used were treated by iron-coating. The efficacy of weed control as affected by golden apple snail has been tested with twice applications of young golden apple snails of 12 kg (24,000 young snails, $0.5g{\pm}10%$ per young snail, 30~40 days after hatching) per ha at the same day after harrowing and applied with rate of 10 kg (20,000 young snails) per ha at 15days after seeding, respectively. The comparison of this experiment was of the conventional machine transplanted rice paddy field in terms of weed control and rice plant injury as a visual grade. The weed efficacy was of 100% similar with the conventional paddy field which was applied by systematic herbicides of pre-emergence and post-emergence chemical herbicides and there was 1~3% significant rice young seedling injury but no yield losses and grain quality due to the input of golden apple snail.

• Journal of Marine Life Science
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• v.5 no.1
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• pp.17-24
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• 2020

We have identified a heat shock protein 70 gene from freshwater snail, Semisulcospira coreana. The freshwater snail HSP70 gene encode a polypeptide of 639 amino acids. Based on bioinformatic sequence characterization, HSP70 gene possessed three classical signature motifs and other conserved residues essential for their functionality. The phylogenetic analysis showed that S. coreana HSP70 had closet relationship with that of golden apple snails, Pomacea canaliculata. The HSP70 mRNA level was significantly up-regulated in response to thermal and salinity challenges. These results are in agreement with the results of other species, indicating that S. coreana HSP70 used be a potential molecular marker in response to external stressors and the regulatory process related to the HSP70 transcriptional response can be highly conserved among species.

• Fisheries and Aquatic Sciences
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• v.24 no.12
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• pp.415-427
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• 2021

Wetland ecosystems act as natural freshwater purification systems, but their rich biodiversity is being threatened with the introduction of the non-native freshwater snail, Pomacea canaliculata. This study was conducted to measure the herbivory effects and growth rate of P. canaliculata on common macrophytes: Ipomoea aquatica, Ipomoea batatas, Pandanus amaryllifolius and Cucurma longa. In separate experiments, the macrophyte species were served as the snails' food as individual species and simultaneously. In the individual treatment, the growth pattern and rate were based on the snails' weight (mg/snail/day; n = 9) while the individual feeding consumption (mg/snail/day) was calculated from the leftover food. In the simultaneous treatment, the herbivory effects were evaluated as the feeding preference (%) from observations every two hours, while the total feeding consumption (mg) was calculated based on the food remaining after a 12-hour experiment (3 replicates: total n = 27). The results indicated that the growth pattern was significant for snails grazing on I. aquatica but not when other macrophyte species were eaten. The individual feeding consumption was higher when using I. aquatica than P. amaryllifolius but the growth rate for snails grazing on I. aquatica and P. amaryllifolius did not differ significantly. Meanwhile, the consumption of C. longa deterred the snails' growth rate. Although the snails consumed all the macrophytes in the individual experiment, when given the species simultaneously, the feeding preference and total feeding consumption were directed significantly more toward I. aquatica than P. amaryfollius and C. longa. We conclude that P. canaliculata is a generalist feeder given a limited choice of food but tends to show a strong feeding preference after being introduced to more food choices. These findings indicate that the introduction of P. canaliculata into wetland ecosystems may increase the herbivory effects on macrophytes, making these ecosystems vulnerable to the impact of eutrophication and biodiversity reduction.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.396-407
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• 2023

The golden apple snail (Pomacea canaliculata) has been utilized as a natural and eco-friendly control of weeds in rice paddy fields. However, P. canaliculata can damage other crops. In this study, the effectiveness of plant extracts from various natural sources that are reportedly effective against pests in the control of P. canaliculata was investigated. The four plant extracts were effective against P. canaliculata and ranked in descending order as green tea seed (Camellia sinensis) > root of red spider lily (Lycoris radiata) > leaves of tobacco (Nicotiana tabacum) > root of sophora (Sophora flavescens). The mortality rate of P. canaliculata was increased using 200 to 2000 mg/kg of green tea seed powder. However, shrubby sophora root extract did not significantly increase the mortality rate. The LC₅₀ and LC₉₀ of green tea seed, tobacco leaves, shrubby sophora root, and red spider lily root were 900 and 2800 mg/L, 956 and 2320 mg/L, 2162 and 5325 mg/L, and 512 and 1054 mg/kg, respectively. The LC₅₀ and LC₉₀ of ground powder of C. sinensis, N. tabacum, S. flavescens and L. radiata were 248 and 646 mg/L, 403 and 733 mg/L, 409 and 905 mg/L, and 493 and 1141 mg/L, respectively. The findings indicate the remarkable control potency of green tea seeds against the golden apple snail. An organic material incorporating the four plant powders may help control green apple snail in an ecosystem-friendly manner.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.109-115
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• 2007

This study was carried out to determine occurrence and damage of golden apple snail, Pomacea canaliculata on water seeding area in Jeonnam province. The density of golden apple snail maintained hlgh until October 2003, but quickly decreased from November. They overwintered only in a portion of the water canals but could not find in dried paddy field. They reproduced from May and June in the canal water and paddy field, respectively. Feeding time of golden apple snail on rice seedlings was 235.2 seconds, feeding length of that was 8.4cm. When golden apple snail fed rice seedlings, the stem remain only 2.5cm from areal part which could not recover. The more density of golden apple snail, the fester feeding rate. Density and number of eggs laid of golden apple snail after overwintering was higher on bank around of paddy field than on middle of that. The percent of shell size after over wintering was higher in small (below 25mm) than big (over 36mm). But in case of Boseong area, the slze was reverse because the soil has soft mud. The survival rate of overwintering golden apple snail was lower than that of breeding. They did not move when the temperature changed rapidly, but the temperature increased they start to move. They dead almost below $-3^{\circ}C$. The damage of rice by golden apple snail in the direct water seeding was 20%. In machine transplanting, rice damaged only fore-end of leaf and recovered subsequently. When golden apple snail release in direct water seeding field, the percent of damage was 5.6% in immediately release plot. The later release, the lower damage.

• Korean Journal of Environmental Agriculture
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• v.38 no.1
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• pp.23-33
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• 2019

BACKGROUND: The golden apple snail(GAS, Pomacea canaliculata Lamarck) is an invasive freshwater snail. It has occurred 34 years since the introduction of the GAS to the Korea. The GASs have been used recently for weed control in wet rice cultivation. The GASs'adaptability to the environment of GAS has been improved and the GASs devour the young stage of the crops as well as weeds. METHODS AND RESULTS: We surveyed the survival area of the snails throughout the country during the winter seasons from 2000 to 2017 and crop damage due to GASs in 2017. Local maximum, minimum, and average air temperatures were monitored daily. The surveyed regions for the survival of the GASs in winters were Gangjin, Goheung, Shinan, Haenam, Gimhae, Haman, Busan, Jeju, and Seogwipo. The survival durations at low temperatures were 12 hours at $-5^{\circ}C$, 1 day at $-3^{\circ}C$, 2 days at $-1^{\circ}C$, 10 days at $0^{\circ}C$, and over 30 days at $3^{\circ}C$. The eggs of GASs were not able to overwinter. The overwintering condition of the GAS needed a water depth of 10-20 cm with well formed mud. Crop damages caused by the overwintering GASs occurred in rice and water dropwort. CONCLUSION: The overwintering GAS was first identified in Haenam, South Korea 2000 after introduction of the GAS. The overwintering area of GAS expanded to the mid-southern parts of Korea. We propose that it has not yet become a pest to rice or any other crop.