Azuki bean beetle (ABB), Callosobruchus chinensis (L.) is a field-to-storage pest of legumes. It is ideal to estimate its field population before it invades the stored legume stuffs. The seasonal occurrence was monitored with rocket traps supplied with synthetic female sex pheromone and with sweep netting during 2015-2016. Harvest damage was evaluated by taking purposive samples of the pods at harvest. Over-wintering stage was identified from the pod samples of left over plants. The results ascertained that October was the peak season of ABB in the azuki bean field. Grain damage and weight loss of the harvested azuki bean were 2.7% and 2.4% respectively, which could be the inoculum for storage loss. The adult emergence only from live pupae collected from pods revealed for its most probable over-wintering stage. In all, this study provides insight into some field ecological parameters of ABB that could be helpful in adopting its management strategies.

The Azuki bean weevil, Callosobruchus chinensis L., is a common insect pest of stored products in the world. Radio-frequencydependent oviposition, development and adult performances of C. chinensis were examined at five radio-frequencies of0 (control), 5, 10, 20, and 30 kHz on azuki bean, cowpea, and mung bean seeds. The effects were studied on two successivegenerations of C. chinensis. The results showed that radio-frequency application have significant effects on the life variablesof C. chinensis. Radio-frequency exposures on three seed species not only impacted on developmental time, adult longevityand adult weight but negative effects were also transmitted to the successive generations. Longer developmental time andthe least adults of C. chinensis were emerged with shorter longevity in case of radio-frequency treatment than untreated.Decreasing the radio-frequency level further reduced the adult longevity and increased time for development of adults.The least adult emergence and short longevity was recorded for 5 kHz treatment. Radio-frequency treatments have alsoaffected on the adult performance such as weight of adult. The life variables of C. chinensis are discussed in terms oftargeting susceptibilities to radio-frequencies in storage as an alternative to chemical treatments.

Callosobruchus chinensis (Coleoptera: Bruchidae) is a cosmopolitan pest of stored grain legumes. This study assessed the effects of short-term exposure to low-temperatures (4, 0, and -4℃) and seven durations of storage (1, 5, 10, 15, 20, 25, and 30 days) on the survival, development, and adult performance of C. chinensis in laboratory. The effects were studied on three life stages (egg, larva [2-3 instar], and pupa) of C. chinensis. The results showed that low-temperature have significant effects on the life variables of C. chinensis. Among the stages, egg and pupa stages were most sensitive to low-temperature. The very low survival rates of eggs and no pupa survived at –4℃ after 10 days storage. Cold exposure at -4℃ not only increased egg and pupa mortality, but the negative effects also transmitted to the larvae and pupa developed from these eggs. Increasing the duration of cold exposure further reduced survival rates. Low-temperature treatments have also affected on the adult performances such as adult weight. However, there were not any negative effects of low-temperatures on the seed germination. The life variables of C. chinensis are discussed in terms of targeting particular susceptibilities to low-temperatures in different storage duration as an alternative to chemical treatments.

To investigate the oviposition preference and development of azuki bean weevil (Callosobruchus chinensis L.), the following six different leguminous seeds were used in this study: red bean (Vigna angularis (Willd.) Ohwi & Ohashi), black soybean (Glycine max (L.) Merr.), soybean (Glycine max (L.) Merr.), seoritae (Glycine max (L.) Merr.), small black bean (Rhynchosia nulubilis) and kidney bean (Phaseolus vulgaris var. humilis Alef.). In the study of oviposition preference, the numbers of eggs per leguminous seed on red bean, black soybean, soybean, seoritae and small black bean were 1.23, 0.61, 0.69, 1.05 and 1.13, respectively. The maximum daily number of eggs was observed at 48 hours and the minimum was at 96 hours. According to each host leguminous seed, developmental time for each host seed was different. The shortest adult emergence time was on red bean (25.27 days). The other five leguminous seeds increased or doubled the adult emergence time. Adult emergence rates feeding on red bean, seoritae, black soybean, soybean, small black bean were 83.33%, 28.23%, 27.87%, 20.44%, and 11.59%, respectively. Emergence rate on red bean was four times higher than the rate on other seeds. The longevity of emerged female adults was almost all longer than that of males. The male adults weighed the lowest of feeding on small black bean. Female adults weighed the lowest of feeding on soybean. Adult weights were the heaviest for both males and females feeding on red bean. As a result, hosts of azuki bean weevil could decrease oviposition rate, emergence rate, adult longevity, and adult weight but increase emergence time. Especially in kidney bean, adult was not completely emerged. No eggs were laid. These results suggest that there might be emergence inhibitors in kidney bean. These imformation might be used to control damages caused by azuki bean weevils.

The azuki bean weevil, Callosobruchus chinensis L., which is one of the notorious stored grain insect pest. Temperature-dependent development of C. chinensis. was examined at six temperatures of 14, 18, 22, 26, 30, and 34℃ on azuki bean and cowpea seeds. The total developmental time (egg to adult) decreased with increasing temperature from 14 to 34℃ on both seeds. However, total developmental time varied from 127.9 and 125.9 days at 14℃ to 19.9 and 20.3 days at 34℃ on azuki bean and cowpea seeds, respectively. The lower temperature thresholds (Tmin) were estimated to be 9.52℃ and 10.36℃, and the thermal constants (K) were 526.31 DD and 454.54 DD, on azuki bean and cowpea using general linear model, respectively, and the lower temperature thresholds and the thermal constants estimated by Ikemoto-Takai linear models were 10.63℃ and 10.79℃, and were 466.18 DD and 436.28 DD, on azuki bean and cowpea, respectively. These findings on thermal requirements and temperature thresholds can be used to predict the occurrence, number of generations and population dynamics of C. chinensis.

팥바구미(Callosobruchus chinensis L.)의 산란 선호성 및 성장조사를 위해 6가지 콩과식물 종자인 팥, 흑태, 백태, 서리태, 서목태, 강낭콩을 선택, 실험을 하였다. 각 종자당 산란수는 팥 1.23개, 흑태 0.61개, 백태 0.69개, 서리태 1.05개, 서목태 1.13개로 나타났으며, 기주식물에 따라 성장시간이 2배 이상 증가하는 것으로 나타났다. 우화율은 팥, 서리태, 흑태, 백태, 서목태( 83.33%, 28.23%, 27.87%, 20.44%, 11.59%), 순으로 나타났으며, 모든 종자에서 팥과 4배 이상의 차이를 보였다. 강낭콩에서 우화는 전혀 없었다. 성충수명은 암컷보다 수컷이 대부분 길었고 암컷의 경우 팥 9.43일, 서리태 8.86일, 흑태 7.88일, 백태 7.17일, 서목태 6.80일로 나타났다. 각 성충의 무게는, 암수모두 팥에서 가장 무겁고, 수컷은 서목태, 암컷은 백태에서 최소무게를 나타냈다. 결과적으로, 팥바구미는 팥 이외의 기주에서는 산란, 우화율, 성충수명, 성충무게 감소가 나타난 반면 우화시기는 증가하였다, 한편 강낭콩은 팥바구미 기주로서는 부적절한 것으로 나타났다.

Six wooden plant essential oils (EOs; Illicium verum, Gaultheria fragrantissima, Bursea delpechiana,Croton anisatum, Cinnamomum cassia and Aniba rosaeodora) and their major compounds (trans-anethole, methyl salicylate, trans-cinnamaldehyde, linalool and linalyl acetate) identified from gas chromatography (GC) and GC-mass spectrometry were tested for adult repellence and pheromone antagonism using Y-tube essay and oviposition deterrent effect using no choice test against adzuki bean beetle (ABB), Callosobruchus chinensis L. EOs of I. verum and C. anisatum as well as their common major compound, trans-anethole were found effective repellents having high degree of pheromone antagonistic and oviposition deterrent activity. Methyl salicylate, the major compound of G. fragrantissima EO (which was only the pheromone antagonist) showed high degree of repellency, oviposition deterrence and pheromone antagonistic effect in higher concentration. From this study, EOs of I. verum and C. anisatum and their common major compound trans-anethole as well as the major compound of G. fragrantissima, methyl salicylate can be screened as eco-friendly management agents against C. chinensis in stored legumes if slow releasing formulations are prepared by future efforts.

Mimosa pudica (미모사), Argemone mexicana (멕시코 가시양귀비) Leucus aspara (꿀풀과 일종), Polygonum hydropiper (여뀌), Blumea lacera (국화과 일종) 등 5종의 식물 헥산추출물들의 팥바구미 성충에 대한 살충, 성충우화억제력 및 녹두 종실피해 방제력이 검증되었다. 그 결과, 밭바구미 성충 살충력은 35-69%이었으며, 녹두에 추출물을 처리한 후 성충우화 방제율은 33-63%, 종실 피해 방제율은 13-49%이었다. 추출물의 농도가 증가할수록 살충력, 성충우화 및 종실피해 방제율 등이 증가하는 것으로 나타났다. 이와 같이 5종의 식물 헥산추출물들은 밭바구미 친환경 방제제로 이용가능성이 있을 것으로 판단된다.

쌀바구미에 적응된 기생봉 Anisopteromalus calandrae를 대체기주인 팥바구미에서 누대 사육하면서 기생천적의 대체기주에 대한 적응과 그의 과정을 조사하였다. A. calandrae기 대체기주에 적응, 안정된 생활사 특성을 보이기까지 2세대가 경과하였다. 성충수명은 단축되어 1세대에서 8.7일을 보였으나 2세대 이후에는 5.7~7.3일의 범위를 나타내었으며 총 산란수는 1세대에서 29.37.7에서 2세대 이후 43.9~68.2의 범위로 증가하였다. 따라서 내적 자연 증가율, 순증가율은 증가하였으며, 개체군 배가 기간은 짧아졌다. 팥바구미에 대한 탐색효율은 적응 전후에 유의한 차이를 보이지 않았으나 탐색효율의 변이계수가 감소하는 현상을 보여 탐색행동이 안정됨을 암시하였다. A. calandrae는 팥바구미에 적응된 이후에도 쌀바구미에 대한 탐색효율이 감소되지는 않았다.