Dysmicoccus brevipes (Cockerell), Dysmicoccus neobrevipes Beardsley and Pseudococcus longispinus (Targioni-Tozzetti) are widely-distributed pests that feeds on many economically important hosts, particularly tropical fruits and ornamentals. The potential distribution of these mealybug pests into South Korea remains a primary concern because of their high incidence in interceptions screened during inspection. Hence, these species prompted a modelling effort to assess their potential risk of introduction. Potential risk maps were developed for these pests with the CLIMEX model based on occurrence records under environmental data. The potential distribution of these pests in South Korea in the 2020s, 2050s and 2090s was projected based on the RCP 8.5 climate change scenario. Results show that D. brevipes, D. neobrevipes and P. longispinus have little potential for invasion in the exterior environment of South Korea due to high cold stress in the 2020s. However, for D. brevipes and P. longispinus, 3 and 86 locations in Jejudo, were predicted to be marginally suitable for this pest under future climate factors, respectively. In that respect, the results of these model predictions could be used to prepare a risk-based surveying program that improves the probability of detecting early D. brevipe, D. neobrevipes and P. longispinus populations.
To replace hazardous methyl bromide (MB) post-fumigation on imported fruits, due to insufficient ventilation process in industrial practice, alternative fumigation with liquid ethyl formate (EF) with N2 application, which is multi benefits to safe to workplace and environment, has been developed by APQA. Although EF was found to be shown proven efficacy to invasive external feeders such as mealybugs and scales on export and imported fruits and vegetables, there was still some conflicts to accept one of the phytosanitary disinfestation method somewhere because of on reliable and confirmative studies on between MB and EF in terms of efficacy to mealybugs on perishable commodities. In here, we evaluated comparative efficacy of EF and MB to target citrus mealybug, which was seems to be hard control pest, based on the current disinfestation guideline of them in Korea. The potential benefits of using liquid ethyl formate (EF) for future quarantine use could provide for safer workplace involved on and post-fumigation such as cold and packing storages, cost-effectiveness as well as meet the environmental friendly solution.
가루깍지벌레(Pseudococcus comstocki)는 전 세계적으로 배를 포함한 과수와 작물에 피해를 주는 해충으로 성페로몬을 이용하여 가루깍지 벌레를 방제하기 위하여 가루깍지벌레 수컷의 온도별 발육과 교미비행 및 비행에 미치는 영향을 조사하여 방제에 적용하고자 본 연구를 수행하였다. 가루깍지벌레의 온도별 발육기간은 15℃에서 알이 산란 및 부화되지 않았고, 25℃까지 발육기간이 짧아지다가 30℃에서 다시 늘어났다. 산란수는 25℃에서 평균 482개로 나타났으며, 성비는 15℃, 20℃, 25℃에서 50%에 육박하였지만 30℃에서 수컷의 성비가 37%였다. 비행패턴은 오전에 비행이 많았고 그 중에서도 해가 뜨고 난 직후 2시간 이내에 가장 많았다. 광주기가 달라지더라도 해가 뜨고 난 후 4시간 사이에 비행하 는 개체가 많았다. 암조건만에서 암수를 사육하는 경우에도 비행이 일어났다. 상승 바람의 풍속에 따른 가루깍지벌레 수컷의 비행을 조사한 결과, 0.5 m거리 일 경우 1.5 mph 이상에서는 비행을 하지 못하였다. 배원에서 수컷의 비행은 2 m 이상에서는 채집되는 개체가 거의 없었고 1.5 m에서 가장 많은 수가 포획되어 트랩을 설치하는 높이로 가장 적합하다고 판단된다. 수컷 방사지점과 트랩 사이의 비행가능 거리를 보면, 0.5 m, 1 m, 5 m까지는 트랩에 잡히는 수가 많았고 10 m, 15 m, 20 m에서 적었다. 다만, 50 m까지도 채집되는 것으로 보아 성페로몬 트랩을 이용하여 50 m 이상 떨어져 있는 수컷도 유인할 수 있을 것으로 사료된다.
귤애가루깍지벌레는 감귤의 주요 깍지벌레 중 하나로 시설재배에서 피해가 심하다. 귤애가루깍지벌레는 밀집하여 발생하는 특성을 갖고 있으며, 귤굴나방이나 잎말이나방류 피해 잎에 기생하고 있어 약제 방제가 어려운 원인이 되기도 한다. 제주지역의 친환경 감귤원을 대상으로 천적곤충과 병원성 미생물을 조사하였다. 천적곤충은 기생성 천척은 Anagyrus sp. 1종과 포식성 천적은 혹파리 일종인 Golanudiplosis japonicus와 꼬마남생이무당벌레 Propylea japonica, 무당벌레 Harmonia axyridis, 풀잠자리 Chrysoperla carnea, 호랑풀잠자리 Micromus sp. 5종이었다. Anagyrus sp. 성충을 황색끈끈이트랩으로 연중 시기별 발생양상을 조사한 결과 5월 하순~11월 상순까지 발생하였으며, 귤애가루 깍지벌레 1세대 기간 동안 2회의 발생성기가 나타났다. 그 외에 곤충병원성 곰팡이 일종인 Paecilomyces sp.가 확인되었 는데, 주로 장마철에 자연발생되고 있었다. 귤애가루깍지벌레 생물적 방제를 위해 수입 천적인 Cryptolaemus montrouzieri (상품명: 깍지무당벌레)를 농가에서 구입하여 활용하고 있다.
Pseudococcus orchidicola and Pseudococcus longispinus, a notorious cosmopolitan pest species of mealybugs, known to be distributed indoors in Korea. The effect of temperature on the development of P. orchidicola and P. longispinus was studied. The duration of nymphal period of the two mealybugs at 24 and 28℃ have been recorded. Developmental duration of P. longispinus was longer than P. orchidicola in both females and males. The adult longevity was estimated to 74.9 and 91.1 days at 24℃ for P. orchidicola and P. longispinus, respectively. The average fecundity per female was greater at 28℃. The survival of P. orchidicola and P. longispinus during winter at outdoor was failed.
Pseudococcus longispinus, a notorious cosmopolitan pest species of mealybugs, known to be distributed indoors in Korea since 2002, is found to be mixed with another species, Pseudococcus orchidicola. Finding P. orchidicola as a pest of tropical plants in Korea is rather unexpected because of their main distribution in Pacific area and South Asia. However, all the available information from morphology, molecule and advices on identification from mealybug specialists indicated this is best matching P. orchidicola. Morphological, molecular and some biological notes on P. orchidicola are provided with some adult and nymphal images, and compared with P. longispinus. A full discussion mainly on identity and distribution of P. orchidicola is given.
Mealybugs (Hemiptera: Pseudococcidae) are major pests of a wide range of crops and ornamental plants worldwide, and represented by 56 species in Korea. Occurrence of, or damage by, the longtailed mealybug, Pseudococcus longispinus Targioni-Tozzetti has not been reported since 2002. However, for the first time in many years, P. longispinus was reported at Phalaenopsis orchids by Kim et al in 2015. Therefore, the present study aimed to investigate the distribution of P. longispinus which is usually found inside a greenhouse or a building where the host plants are. We have collected 129 mealybug samples at 254 sites from Korea. Among these, 27 of P. longispinus and 62 of an unidentified Pseudococcus species were found mainly in ornamental plants such as Heteropanax fragrans, commonly known as happy trees in Korea. Morphological characteristics of the unidentified mealybug were very similar to those of P. longispinus. However, the genetic variability in COI sequence comparison was significantly different between the two species. Further studies are needed to clarify the valid name for this unidentified species, and we are currently working on it.
In Korea, six mealybug species have been reported on pears. This study investigated the occurrence of mealybugs in 19 pear orchards from 2013 to 2014. Two species, Crisicoccus matsumotoi (Siraiwa) (Hemiptera: Pseudococcidae) and Pseudococcus comstocki (Kuwana) were mainly found. The dominant species was C. matsumotoi identified on 73% of infested fruit. Toxicities of 14 registered insecticides (7 single formulations and 7 mixed formulations) commonly used to control P. comstocki were evaluated to C. matsumotoi nymphs and adults at the recommended concentration. As a results, all insecticides exhibited strong insecticidal activity with 100% mortality of both nymphs and adults. These results indicate that the 14 insecticides can be used in control for C. matsumotoi in field.
Methyl bromide(MB) is a fumigant for quarantine and pre-shipment(QPS) that can eradicate target pests within short fumigation periods. However, MB, an ozone-depleting substance, is scheduled to be phased out in the second decade of this century. In contrast to MB alternatives for soil fumigation, there is no ideal alternative fumigant to MB for QPS of perishable commodities. It is important that all target insect pests are killed within a short fumigation time.
The citrus mealybug(Planococcuscitri), a problematicquarantine pest from Korea, was exposed to ethyl formate and phosphine for different times and to different concentrations of EF(0.0∼33.4 mg/L) and PH3(0.25∼1.0 mg/L) in small desiccators. The eggs showed more tolerance than the nymphs and adults. To control the eggs, they were treated with a mixture of EF and PH3 for 2 and 4-hr. The egg stage showed 100% mortality with EF:PH3(25.1:0.25, 16.7:0.5, and 16.7:1.0 mg/L) at 4-hr. Treatment with a mixture of EF and PH3 for 4-hr at 8°C can control all stages of the citrus mealybug.
Methyl bromide (MB), as a fumigant for Quarantine and Pre-Shipment(QPS) could offer eradication of target pests within shorter fumigation period and without phytotoxicity. Therefore, unlike MB alternatives for soil fumigation, there is no ideally MB alternative fumigant for QPS purpose, particularly for perishable commodities. It is critically important that within shorter fumigation time requires killing all target insect pests and without effect of quality and deliver treated fruit and vegetables to the final consumer.
The citrus mealybug(Planococcuscitri), problem quarantine pest, was tested with different exposure times(2 and 4-hours) and concentrations(EF(0-200 g/m3) and PH3(10-50 g/m3)) in small desiccators for mixture tests. On sensitivity test with small desiccator, the egg stage showed 100% mortality with 200/25(EF/PH3) g/m3 and the nymph and adult stage showed 100% mortality with 10/10(EF/PH3) g/m3 on 2h. Also, the egg stage showed 100% mortality with 150/25(EF/PH3) g/m3on 4h.
Though quarantine use of methyl bromide(MB) is currently permitted in Korea, there has been phasing out and considering ban in many countries due to their ozone depletion properties. VapormateTM, a new gas formulation of ethyl formate(EF) with carbon dioxide, and VivakilTM, a new gas formulation of phosphine(PH3) with carbon dioxide, are MB alternative fumigants to methyl bromide(MB). For applying on import commodities, the efficacy of EF and PH3 was evaluated for 2hr fumigation on egg, nymph and adult stage of citrus mealybug(CMB), Planococcus citri, at two different temperatures(8, 13℃). The CT(Concentration X Time) product of EF to be expect 99% mortality to egg, nymph and adult stage of CMB were 108.3, 22.4 32.4 gh/m3 at 8℃ and 83.2, 25.1, 29.8 gh/m3 at 13℃, respectively. The CT product of PH3 gas to be expect 99% mortality to nymph and adult stage of CMB were 6.50, 2.55 gh/m3 at 8℃ and 3.72, 3.64 gh/m3 at 13℃, respectively. However, PH3 gas applied at high CT(4.2 gh/m3) for 2hr fumigation was not enough to obtain CT to egg stage of CMB at both temperature conditions. These efficacy data based on CT will be useful to predict the CT model in scale-up fumigation at diverse practical conditions.
본 시험은 ‘추황배’ 과실에 봉지 종류를 달리 하였을 때 과실품질과 과피흑변 및 가루깍지벌레 발생 변화를 분석하기 위하여 수행되었다.
1. 농가 조사에서 신문지외지/흑색내지로 이중괘대를 한 과실이 13.2%의 과피흑변과가 발생하였고, 신문지외지/롤내지가12.3%, 백색외지/황색내지가 7.2%의 과피흑변발생이 관찰되었다.
2. 투기도와 투습도는 신문지외지/흑색내지가 가장 불량하였고, 백색외지/백색내지가 흡광도, 투기도, 투습도에서 양호한것으로 나타났다.
3. 괘대봉지에 따른 과실품질은 과피의 적색을 나타내는 a값을 제외하고는 별다른 차이가 관찰되지 않았다.
4. 수확 후 과피흑변과와 가루까지벌레 발생률을 조사한 결과, 백색외지/백색내지에서 가장 낮았고, 백색외지/황색내지가다음으로 낮았다. 반면에 백색겉면외지-흑색안면외지/황색내지는 수확후와 저온저장 14일, 21일 후에도 과피흑변과 발생이꾸준히 높게 나타났다.
5. 과피내 폴리페놀함량이 높을수록 과피흑변이 증가하는 것으로 관찰되었다.
최근 들어 하우스재배 감귤을 중심으로 발생이 증가하고 있는 귤애가루깍지벌레에 대해 효율적인 발생예찰과 함께 방제시기를 결정하기 위하여 합성 성페로몬을 이용하여 시기별 발생특성을 조사하였다. 귤애가루깍지벌레의 수컷 성충은 합성 성페로몬뿐만 아니라 색에도 반응하였다. 성페로몬의 농도는 5.0 mg까지 농도가 증가할수록 유인력이 높았다. 귤애가루깍지벌레 수컷 성충은 연 4회 발생되고 있었으며, 월동 후 수컷 성충이 처음 발생되기 시작하는 시기는 4월 중하순이었다. 수컷 성충발생이 가장 많은 시기는 제 1세대 발생기인 7월 상중순이었다. 성페로몬트 랩에 유인된 귤애가루깍지벌레 수컷 성충은 한 세대 내에서 3회의 발생성기가 나타났으며, 이는 귤애가루깍지벌레가 1~3령 약충으로 월동하기 때문인 것으로 추정되었다. 트랩에 유인된 수컷 성충의 밀도와 나무의 가지당 평균밀도와는 높은 정(+)의 상관을 갖고 있었다. 수컷 성충의 최대 유인시기를 이용하여 1령 약충 발생 시기를 추정할 수 있었으며, 그 적산온도는 산란전 기간과 비슷한 350DD이었다.
The legless mealybug, Antonina nakaharai Williams and Miller (Hemiptera: Pseudococcidae) is recorded from bamboos (Poaceae) in Korea. An identification key to adult females of three species of Antonina from the Korean Peninsula is also provided.
The males of cryptic mealybug, Pseudococcus cryptus, were attracted on trap baited with or without a synthetic sex pheromone. The attractiveness of sex pheromone trap was higher than yellow-color sticky trap, but both phenologies were similar. There was a positive relationship between mean density of 2nd nymph to adult cryptic mealybug and the density of the male caught on trap. The density of cryptic mealybug per tree was higher correlated with yellow-color sticky trap than sex pheromone trap. The pattern of cryptic mealybug male occurrence had two to three cohorts in a generation resulted from overwintering stage. The maximum occurring time of 1st to 2nd nymph stage could be estimated from the peak time of trap catch by effective temperature accumulation. The higher and lower threshold temperature was estimated as 10.9 and 32.6℃, respectively and its thermal constant was 360 degree-day. The cryptic mealybug parasitoid, Anagyrus sp., which was first recovered in Jeju in 2009, was well attracted on yellow-color sticky trap. There was a high correlation between the density of Anagyrus sp. and of cryptic mealybug males caught on trap.
Some responses of cryptic mealybug, Pseudococcus cryptus, for a sex pheromone, [(1R,3R)-3-isopropenyl-2,2-dimethylcyclobutyl]methyl 3-methyl-3-butenoate, were studied to develop the applying strategy of sex pheromone trap for efficient monitoring and control-time decision in citrus orchards grown in greenhouse for 2 years (2007-2008). The optimal concentration of a sex pheromone was 1.0㎎ per hexane 100㎕ in a using pheromone lure. There was no significant effect of the attraction of male adults among different colours (white, blue and yellow) of plate-type trap baited with sex pheromone. The more male adults were attracted, as the distance of a pheromone trap form a citrus tree infested with cryptic mealybug was closer. The male adults were caught to sex pheromone trap from middle April to late November, and its peak period was the middle of July. The thermal constant for the next attraction was about 640 degree-days (lower threshold temperature=12℃) after confirmed the first attraction of male adults. The optimum control time for cryptic mealybug after the first attraction of male adults were confirmed was estimated as 450 to 500 degree-days.