우리나라에서 흰등멸구는 매년 해외로부터 비래, 정착한 후 2~3세대를 경과하며 벼의 생육 및 품질 저하에 영향을 미치는 벼의 중요 해충 중 하나이며, 비래해충의 경우 비래 후 세대에 따른 변화 양상을 정확하게 예측하는 것은 방제시기와 방제수단을 결정하는데 중요하다. 공시충은 2018년 사육실에서(25±2 ℃, 60±5% RH, L:D=16:8) 누대사육하여 사용하였다. 흰등멸구가 국내에 비래 후 3세대까지 세대증식하면서 피해를 주는 것으로 가정하여 1세대와 3세대 간의 발육과 산란 등을 조사하였으며 얻어진 결과를 토대로 생명표를 작성하였다. 약충기간은 1세대와 3세대에서 각각 14.5일, 13.6일, 암컷 성충기간은 각각 17.2일, 11.8일로 나타났으며, 우화율은 98.3%, 85.0%로 조사되었 다. 산란기간은 각각 6.8일, 6.0일이었으며 산란수는 47.5마리, 122.6마리로 세대가 늘어나면서 증가하는 것으로 나타났다. 생명표 분석 결과, 순증가율, 내적자연증가율이 각각 5배, 1.7배 증가한 것으로 나타났다.

Ostrinia scapulalis (Lepidoptera: Crambidae) overwinters as a final instar larva. In order to elucidate phenology of the insect, we studied several factors related to its overwintering. Neonate larvae from early August to early October entered overwintering through outdoor rearing. Pupation and adult emergence were observed during the periods from May to June, next year, and from May to July, respectively. Heat addition by 25oC to overwintering larvae induced shorter prepupal periods with progressing season. Supercooling points of overwintering larvae during the period from October to April were below -20oC, and those temperatures were significantly lower than those of a laboratory colony. It was estimated that higher content of glycerol in hemolymph is responsible for cold-hardiness as a cryoprotectant during overwintering.

The Asian corn borer, Ostrinia furnacalis (Lepidoptera: Crambidae), produces final instar larvae of overwintering stage in response to decreasing day-length and temperature, and then those larvae pupate after about 6-8 month. In this study, we investigated a few properties related to cold hardiness during overwintering of the insect. Overwintering larvae collected in December could survive at least for 16 days at -20oC, while all larvae of a laboratory colony, which was reared at 25oC, 15L/9D, died within 2 hours. Supercooling points of overwintering larvae were below -20oC, and the temperatures were significantly lower than those (ca. -10oC) of the laboratory colony. It was estimated that higher content of hemolymph glycerol is responsible for cold-hardiness as a cryoprotectant during overwintering of O. furnacalis.

Polyphenol profiles, physicochemical properties, antioxidant activities, and inhibitory effect of adipocyte differentiation of Houttuynia cordata fermented with Lactobacillus brevis B84 were evaluated. Six polyphenols were characterized for this plant by using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and the results were compared with total phenolic content by a spectrophotometric method. The total amount of the identified polyphenols was lower than that determined by the spectrophotometric method. However, the fermentation process influenced polyphenol composition such as content of vanillic acid and caffeic acid. The phytochemical profiles were evaluated by high-performance liquid chromatography with UV and electrospray ionization mass spectrometry detection (HPLC-DAD-ESI-MSn). Total sugar and reducing sugar contents decreased after fermentation. Antioxidant activities such as DPPH, ABTS, and superoxide anion radical scavenging and reducing power were evaluated to compare the beneficial effect after fermentation. Fermented H. cordata increased the lipolytic effect in 3T3-L1 adipocytes. Overall, the results indicate that the fermentation of H. cordata with L. brevis B84 produces changes of phenolic compounds, antioxidant activity, and lipolytic effect.

The physical and chemical properties of corrugated cardboard-based media were evaluated to assess their suitability as substrates for plants. Samples were collected periodically from the same study area over 5 months to determine any seasonal variabilities. In addition to the corrugated cardboard-based media, the rural soil of the study area was used as the control. The corrugated cardboard-based media showed adequate levels of moisture content and bulk density and correspondingly high porosity values when compared with the rural soil. All corrugated cardboard-based media showed adequate levels of electrical conductivity, organic matter, and correspondingly high cation exchange capacity values when compared with the rural soil in all seasons. The C/N ratio of the corrugated cardboard-based media was similar to the optimal values of 15-20. However, the pH values of the corrugated cardboard-based media were lower than the optimum value(pH 4) for plant growth and rural soil. The moisture content value which cycle bobs up and down according to sampling date, and this means that the moisture content is affected by seasonal changes in the components entering the study area. The corrugated cardboard-based media appear to be acceptable for growing plants(Lotus corniculatus var. japonicus). Finally, the use of this media permits better vegetation establishment than the use of rural soil. Our results prove that corrugated cardboard-based media can exhibit higher plant cover over a long period(September-November) as opposed to rural soil. Our study demonstrates the effectiveness of corrugated cardboard-based media for plant growth, and we recommend that future studies should focus on potential materials relevant to revegetation and management.

누에는 약제, 면직, 식용, 동물 사료 등에 활용도가 높아 동아시아에서 오랫동안 사육되어 왔다. 뽕잎을 먹고 자란 누에가 사료를 먹고 자란 누에보다 생장주기가 일정하고 더 건강하게 생장한다는 것은 잘 알려진 사실이다. 또한 최근의 연구에 따르면 동물 장내 미생물이 동물의 면역과 생장에 큰 역할을 한다고 알려졌다. 이러한 사실로부터 뽕잎에 존재하는 미지의 미생물이 누에 생장과 면역에 관여할 수 있다는 가설을 세우고 이를 확인하기 위한 연구를 수행하였다. 뽕잎 내생균을 분리하기 위해 뽕잎을 5mm 크기로 잘라 표면살균 후, 배지에 치상하여 자라나오는 세균을 분리하여 동정하였다. 흥미로운 점은 100개 이상의 뽕잎 절편으로부터 동일한 세균이 검출되었으며 계통학적 분석을 통해 동정한 결과, Pseudomonas syringae pv. syringae(Pss)로 확인되었다. 또한, 뽕잎을 섭식한 누에의 장 속과 분변에서 이 균의 존재를 확인하였다. 누에에 병을 일으키는 곤충병원성 곰팡이에 대한 Pss의 항진균 효과를 확인하기 위해 곤충병원성 곰팡이인 Beauveria bassiana, Cordyceps militaris와 식물병원성 곰팡이 Botrytis cinerea, Fusarium graminearum을 대상으로 대치배양을 통해 균사 생장 억제 정도를 확인하였다. 그 결과, 식물병원성 곰팡이의 생장 억제효과는 관찰되지 않았으나 곤충병원성 곰팡이의 생장이 50% 이상 감소되었다. 특히, 다량의 포자를 생성하여 곤충에 치명적인 병을 야기하는 B. bassiana의 균사 생장이 C. militaris에 비해 더 크게 감소하였을 뿐 아니라 Pss의 배양 추출물을 처리하였을 때 B. bassiana의 포자 발아가 지연되었다. 앞으로 누에 장 속에 안착한 Pss가 곤충병원성 곰팡이에 대한 면역력과 누에 생장에 미치는 영향을 확인해 볼 계획이며 이를 통해 건강하고 안정적인 누에 사육에 활용될 수 있는 미생물 제제를 만들고자 한다.

Japanese pine sawyer beetle, Monochamus alternatus Hope (Coleoptera: Cerambycidae) is considered as a serious pest in pine trees. To develop an eco-friendly strategy to manage this forest insect, we collected entomopathogenic fungi from Korean soil and assessed their virulence against the adults of the insect in laboratory conditions. As a result, two isolates with conidial suspension (1.0×107conidia/ml), showed 87% and 90% mortality 12 days after fungal treatment, respectively. We assessed the potential of the fungi-derived destruxin and protease as additives to the fungal isolates, and they showed insecticidal activity via feeding and spraying treatments. Finally, we produced fungal conidia in massive solid cultures and formulated wettable powders, and now studying optimal conditions of oil-based formulation with two isolates. Based on these results, we are evaluating the control efficacy of the fungal agents against M. alternatus in field conditions.

The objectives of this study was to evaluate the degradability and digestibility of crude protein (CP), rumen undegradable protein (RUP), and individual amino acids (AA) on six by-product feedstuffs (BPF) (rice bran, RB; wheat bran, WB; corn gluten feed, CGF; tofu residue, TR; spent mushroom substrate from Pleurotus ostreatus, SMSP; brewers grain, BG) as ruminants feed. Three Hanwoo steers (40 months old, 520 ± 20.20 kg of body weight) fitted with a permanent rumen cannula and T-shaped duodenal cannula were used to examine of the BPF using in situ nylon bag and mobile bag technique. The bran CGF (19.2%) and food-processing residue BG (19.7%) had the highest CP contents than other feeds. The RUP value of bran RB (39.7%) and food-processing residues SMSP (81.1%) were higher than other feeds. The intestinal digestion of CP was higher in bran RB (44.2%) and food-processing residues BG (40.5%) than other feeds. In addition, intestinal digestion of Met was higher in bran RB (55.7%) and food-processing residues BG (44.0%) than other feeds. Overall, these results suggest that RB and BG might be useful as main raw ingredients in feed for ruminants. Our results can be used as baseline data for ruminant ration formulation.