Ips acuminatus (Coleoptera: Curculionidae) is one of the potential pests of various species of pines. To investigate the effects of thinning on I. acuminatus and Stigmatium pilosellum (Coleoptera: Cleridae), known as a natural enemy of bark beetles, were examined in Korean pine (Pinus koraiensis) forest in Chuncheon, South Korea in 2014. Three study site were selected - two sites (western slope and southern slope) that thinning was conducted in early spring 2014 and a site without thinning within 5 years. I. acuminatus and S. pilosellum were collected every week or fortnightly using the 12-unit Lindgren multi-funnel traps with pheromone lure (Ipsdienol +50/-50 40mg, Ipsenol +50/-50 40mg) from May to early October. The densities of I. acuminatus, the dominant species of bark beetles, were maximum 8.4 ± 0.9 and 1.4 ± 0.4 individuals/trap/day at thinning site and non-thinning site, respectively. In case of S. pilosellum, the dominant species of Cleridae, its densities were 17.7 ± 2.4 and 2.6 ± 0.8 individuals/trap/day at thinning site and non-thinning site, respectively. I. acuminatus showed first emergence peak on June and second emergence peak on September, but S. pilosellum showed only one time emergence peak on June – the density of S. pilosellum increased along with the density of I. acuminatus (r = 0.66, p = 0.0365). Our results shows that thinning in Korean pine forest increases the densities of I. acuminatus and S. pilosellum, reflecting increase in their food resources available.

The effects of a newly developed flower thinning formulation (FTF) on the vitality of the honey bee Apis mellifera were examined by measuring the activities of various digestive enzymes in adult worker bees. First, direct spraying of the FTF solution did not cause any behavioral changes or lethal effects for the honey bees based on 24 h observation. Second, oral ingestion of a sugar solution containing the FTF did not produce any significant change in the activities of amylase, proteinases, lipase, or acetylcholine esterase (AChE) in the worker bees 6 h or 24 h after treatment. Meanwhile, a commercial formulation containing sulfur compounds showed slightly reduced activities for several digestive enzymes and AChE, although no behavioral disturbance. Thus, the results of the present study suggest that the FTF is not toxic for honey bees, in terms of contact and ingestion. Therefore, this newly developed FTF can be used for flower thinning without any detrimental effects on pollinating insects.

The effects of thinning on community diversity of wood-boring beetles were examined in Japanese Larch (Larix kaempferi) forest in In-je, South Korea in 2013. Three study sites were selected and thinning in the plots was conducted in 2010, spring 2012, and autumn 2012, respectively. Wood-boring beetles were collected every week using the 12-unit Lindgren multi-funnel traps with pheromone lure (Ipsdienol +50/-50 40mg, Ipsenol +50/-50 40mg) from mid-April to early November. Total 5 families (Cerambycidae, Curculionidae, Dryophthoridae, Scolytidae, Platypodidae), 62 species, and 26,638 individuals were collected. Diversity indices were 2.08, 2.02 and 0.76, and evenness indices were 0.55, 0.49 and 0.19 in 2010, spring 2012 and autumn 2012 thinning area, respectively. Among wood-boring beetles, the number of species of bark and ambrosia beetles were accounted for 44.4, 41.9 and 46.3% in 2010, spring 2012 and autumn 2012 thinning area, respectively. The number of individuals of bark and ambrosia beetles were accounted for 86.9, 82.2 and 98.4% in 2010, spring 2012 and autumn 2012 thinning area, respectively. Our results showed that the density of wood-boring beetles was the highest in the most recent thinning area, suggesting that thinning timing can influenced on the abundance of bark and ambrosia beetles. Among them, Ips subelongatus, I. acuminatus, and I. sexdentatus are species that mainly attack Japanese Larch. Ips subelongatus emerged faster than others and was the most dominant species.

본 연구는 하이부쉬 블루베리(Vaccinium corymbosum) 'Jersey' 품종을 이용하여 적방 1/3, 적방 1/3 +적화 1/2, 적방 2/3 및 적방 2/3 + 적화 1/2처리 후 무처리 과실의 수확량과 과실 품질을 조사하여 적방 적화 정도에 따른 수량과 과실 크기, 가용성당함량, 산함량, 과실 경도를 분석하였다. 적방 적화 처리는 과립중, 종경 및 횡경에 유의한 과립 비대효과를 가져왔다. 과실 수확량은 무처리와 적방 1/3 처리구에서 가장 높았으며, 그 이외의 처리에서는 과립비대는 이루어졌으나 수확량의 감소가 발생하였다. 무처리와 적방 1/3 처리의 경우 전체 수확량은 비슷하였으나, 적방 1/3 처리구에서는 상품성이 큰 대립의 과실이 차지하는 비율이 무처리에 비해서 큰 것으로 조사되었다. 가용성당함량은 적방과 적화 처리에 따라 수량이 감소한 적방 2/3, 적방 2/3 + 적화 1/2 처리구에서 유의하게 증가하였으나, 산함량과 경도에는 영향을 미치지 않았다. 적방 적화에 따른 영향은 과립 비대와 수량에 유의한 차이를 주었으나 과실품질에는 크게 영향을 미치지 않는 것으로 조사되었다.

Thinning treatment has a huge effect on understory and litter structures in forest ecosystem, and the resulting changes may impact some arthropod groups such as plant-feeders and detritivores. This study was carried out to find a change in arthropod abundance and their structures in relation to the thinning activity in a Pinus koraiensis plantation in Chuncheon, Korea, where thinning was conducted twice: in 1998-2000 (old-thinning) and 2007 (new-thinning). Arthropods were collected using pitfall traps in 2006 and 2008. Effects of old-thinning on change of abundance and community structure of arthropod were significant, but the effects of new-thinning were not significant. The most significant thinning effect was found in detritivores, followed by plant feeders, but the effect was hardly significant in predators. Among detritivores the changes in abundance was diverse. The abundance of orthopteran plant-feeder increased, but Curculionidae declined after thinning. There was not different in abundance of total arthropods between thinned and unthinned areas because the difference may have cancelled each other out by increased or decreased abundance of taxa. Community structures of arthropods were most greatly affected by years, followed by the old-thinning, but the new-thinning did not affect community structures.

Background: The cultivation of ginseng (Panax ginseng C. A. Meyer) in greenhouses could reduce the use of pesticides and result in higher yield; however, construction costs are problematic. The adaptation of direct-sowing culture in greenhouses could reduce the cost of ginseng production. Methods and Results: To improve seedling establishment in direct-sowing culture, effects of sowing density (SD), number of seeds sown per hole (SN), and thinning (TH) treatment on the root yield were investigated after 3 years of seeding. The emergence rate was significantly influenced by SD, but not by SN or TH. Damping-off and rusty roots increased with an increase in SN with diminishing effects of SN on seedling establishment. Root weight and diameter were affected by SD, SN, and TH, however, there were no statistical significances. The total number of roots harvested per unit area increased with increasing SD and SN, and the weight of roots was affected by SD, but not by SN or TH. Conclusions: Multi-seed sowing per hole and/or thinning might not be an efficient method for the direct-sowing culture of ginseng. The SD for direct seeding culture in greenhouses should be approximately 33 - 42 seeds/㎡ for an optimum yield of 3-year-old ginseng.

송이다듬기는 포도의 품질을 높이기 위해 송이의 크기를 조절하고 송이모양을 변형시키는 유용한 재배방법이다. 포도 'MBA' 품종의 송이다듬기에 따른 과실 및 포도주의 품질 특성을 확인하기 위해 송이줄기의 곁가지를 제거하였는데, 상위지경부터 4, 5, 6지경을 남기고 절단 한 뒤 관행처리 대조구와 비교하여 수확기에 과방 및 와인의 품질을 조사하였다. 포도송이의 품질은 지경수가 작을수록 당도가 증가하고 총산이 감소하는 양상을 나타내었다. 포도주의 양조