• Weed & Turfgrass Science
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• 제5권4호
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• pp.203-212
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• 2016

농약의 오남용을 방지하고 안전한 농산물을 생산하기 위한 일환으로 농약 등록 후에 농가에서 사용되는 농약 사용실태 및 작물별 단위면적당 농약사용량을 조사하였다(2012-2015). 약해피해에 대한 조사에서는 과채류가 14%로 가장 높았고, 벼, 과수류, 엽채소류는 각각 11%, 11%, 8%순으로 나타났다. 농약안전사용 수칙 준수 여부에 관한 7개 항목 중 농약사용량 준수 등 6개 항목은 대부분 잘 지키고 있었으나, 보호구 착용의 비율은 상대적으로 낮았다. 단위면적당 농약사용량($kg\;a.i.\;ha^{-1}$)조사결과는 엽채소류 6종(1.65), 과채류 6종(4.93), 과수류 6종(10.98), 벼(3.16) 순이었으며, 선행 조사 보다 사용량은 대체로 감소하는 경향이었다. 이는 성분함량이 높은 농약보다 고 효율화된 농약개발과 함께 사용량도 감소하고 있기 때문이라고 판단된다. 수도용 제초제는 Butachlor 등 43종의 농약 성분이 사용되었으며 단위면적당 1.3 kg이 사용되었는데, 벼에 사용된 농약 중 제초제는 44%에 달하였다. 설포닐우레아(SU)계통 농약 사용은 9종으로서 2015년 단위면적당 사용량($kg\;a.i.\;ha^{-1}$)은 2015년 조사시점에는 2011년 11월에 새롭게 등록된 Metazosulfuron 0.0113을 포함하여 0.0407로 2007년보다는 20% 낮고 2011에 비해서는 31% 높은 증가율을 보였으며, 살균제 및 살충제의 사용량 감소와는 달리 제초제 사용량은 현재와 같이 지속될 것으로 판단되었다.

• 한국버섯학회지
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• 제14권3호
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• pp.119-126
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• 2016

표고버섯 원목재배시 고온피해를 경감시키기 위하여 임가실증지 5개소를 선정하였고, 기존 1중(비닐+차광)재배사의 내부 지붕에 2중으로 차광망을 추가 설치(개선형)하였다. 기존 재배사와 개선형 재배사 형태에 따른 내부 온습도, 균사 만연도 및 버섯 생산성을 조사하였다. 조사결과 시설 내부 최고온도는 개선형 재배사가 기존 1중 재배사 보다 평균 약 $3{\sim}5^{\circ}C$정도 낮았으나, 평균습도는 그와 달리 기존 1중 재배사와 개선형 재배사간에 큰 차이는 없었다. 특히 기존형과 개선형 재배사 모두 임내 재배장보다 평균습도가 10% 정도 낮아 건조한 불량환경이 유지되어 버섯 품질과 생산성 향상을 위해서는 지속적인 수분관리가 중요함을 알 수 있었다. 버섯목 표면, 내부의 균사 만연도를 비교한 결과 개선형 재배사가 가장 우수하였고, 임내재배사, 기존 1중 재배사가 순으로 저조하였다. 버섯 생산성을 비교한 결과 기존 1중 재배사에 비하여 117~204% 증수 효과가 있었으며, 재배사 동고 높이가 낮을수록 개선효과는 극대화 되었다. 따라서 시험결과를 토대로 고온피해 경감을 위한 원목재배사 모델 5종을 제시하였다.

• 한국응용곤충학회지
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• 제43권3호
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• pp.189-194
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• 2004

1998년부터 2000년까지 3년간 경북사과주산지 사과원과 묘목원을 대상으로 잎말이나방류 종을 조사하였으며, 1992년부터 2001년까지 10년간 5-6개 시군의 관행사과원과 폐원에서 잎말이 나방 발생동향과 피해정도를 조사하였다. 사과원에 발생하는 잎말이나방으로는 애모무늬잎말이나방 (Adoxophyes orana), 사과무늬 잎말이나방(Archips breviplicanus), 매실애기 잎말이나방(Rhopobota unipunctana), 사과잎말이나방(Choristoneura longicellana), 복숭아잎말이나방(Acleris fimbriana), 감나무잎말이나방(Ptycholoma lecheana circumclusna), 한국잎말이나방(Archips subrufanus) 등 총 7종이 조사되었다. 이중 애모무늬잎말이나방이 매년 단연 우점종이었으며, 사과무늬잎말이나방과 매실애기잎말이나방은 특정 해에만 1-2 농가에서 다발생하였다. 1980년대 우점종은 사과무늬잎이나방과 매실애기잎말이나방이였으나, 1990년대말 우점종 변화가 이루어진 것으로 조사되었다. 10년간 관행사과원의 잎말이나방 피해정도를 조사한 결과, 평균 피해과율은 $0.67\%$였다. 과실 피해는 3세대 유충에 의해 8-10월에 집중적으로 이루어졌다.

• Journal of Biosystems Engineering
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• 제40권4호
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• pp.409-416
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• 2015

Purpose: This study evaluates a new banana bulk packaging method under the real transport conditions of Sri Lanka. Methods: A field evaluation of optimized 8-mm thick Styrofoam sheets used as the cushioning material was applied. A trial transport was conducted from Thambuttegama to Colombo using a medium-sized open truck, with banana leaves as the control material. Data were recorded at the farmer, transporter, retailer, and consumer stages of the supply chain. Mechanical damage, physiological loss in weight, fruit firmness, total soluble solids, ripeness index, visual quality ratings, and the physical damage index of the bananas were measured at each stage. A cost-benefit analysis was also conducted for both packaging methods. Results: The 8-mm styrofoam sheets significantly reduced (p < 0.05) the mechanical damage from 26.3% to 12.9% compared to the conventional method for long-distance transport, and the physiological loss in weight showed a decrease of 2.88%. The loss of firmness of the fruits followed a simmilar pattern for both methods until reaching the retailer, but at the consumer was significantly higher (p < 0.05) for the control. However, the physical damage index at the retail stage for the control showed symptoms of physical injury, whereas the bananas transported using the cushioning materials exhibited only minor symptoms. Further, the visual quality of the fruits after transport from the farmer to the consumer was preserved, which is one of the main factors affecting consumer preference and retail price. The proposed method increases the profit margin by 51.2% for Embul bananas owing to the reduced postharvest losses. Conclusion: The 8-mm thick Styrofoam sheets reduced the physical damage to the bananas, with the quality parameters maintained at the prefered level. Moreover, profits may be increased.

• International Journal of Industrial Entomology and Biomaterials
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• 제33권2호
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• pp.41-49
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• 2016

We bred a mulberry cultivar named Shimgang, through local adaptability test, which is under registration as a new cultivar for fruit production. Local adaptability test had been carried out at four local places(Suwon, Chuncheon, Buan and Jinju) for five years from 2011. This variety 'Shimgang' belongs to Morus Microphylla Buckl. selected from seedlings imported from USA. Shimgang was resistant to popcorn disease and high yielding variety in fruit productivity by 111% compared to control cultivar 'Shimheung(Morus alba L.)' for three years. Although fruits of 'Shimgang' was smaller in size and lower in sugar content of mulberry fruits, it showed stronger resistance than that of 'Shimheung'. It is adaptable to every where except the places where cold and late frost damage happen frequently.

• 한국포장학회지
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• 제21권2호
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• pp.67-71
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• 2015

Shock and vibration inputs are transmitted from the transporting vehicle through the packaging to the fruit during the parcel delivery service. The vibration causes sustained bouncing of fruits against each other and the container wall. The steady state vibration input may cause serous fruit injury, and the damage is particularly severe if the fruits are bounced at its resonance frequency. The determination of the resonance frequencies of the fruits and vegetables may help the packaging designer to determine the proper packaging system providing adequate protection for the fruits, and to understand the complex interaction between the components of the fruits when they relate to expected transportation vibration inputs. To analyze the vibration properties of the apples for optimum packaging design during transportation for parcel delivery service, random vibration tests were carried out. In the random vibration test, the resonance frequency and PSD of the apples in packaging system for parcel delivery service in the test were in the range of 13 to 99 Hz and $0.0143{\sim}0.0923G^2/Hz$.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.137-143
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• 2009

Pre-dispersal seed predation by a granivorous bird, the masked grosbeak (Eophona personata, Fringillidae), was investigated in two bird-dispersed trees, Celtis sinensis and Aphananthe aspera (Ulmaceae). The objectives of this study were to 1) measure direct damage of predation by grosbeaks on plant crops, 2) reveal the temporal pattern of predation within each tree species and its causal factors, and 3) test whether foraging grosbeaks hinder foraging of frugivorous birds, thereby indirectly impacting the reproduction of both tree species. A substantial amount of fruit and seed crop was consumed by grosbeaks (24.3% in Celtis; 55.5% in Aphananthe), and only 17.7% (Celtis) and 16.7% (Aphananthe) were removed by frugivorous birds. At the study site, the grosbeak population size fluctuated greatly during the fruiting seasons of both plant species. As for Celtis, predated seed density also fluctuated temporally, and the local population size of grosbeaks was responsible for predated seed density. In Aphananthe, predation was not fully explained by grosbeak populations or plant phenology, but its peak coincided with that of grosbeak population. These results suggest that predispersal seed predation by granivorous birds can have large negative impacts on the bird-dispersed plants. Changes in local population size of granivorous birds can influence predatation and can affect reproductive success of the bird-dispersed plants available to the birds.

• 한국토양비료학회지
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• 제51권1호
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• pp.28-34
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• 2018

Yuzu (Citrus junos) gummosis disease, caused by Phytophthora nicotianae, was first reported in 1997. As known in citrus, Phytophthora is the most fastidious soil-borne pathogen to control. In order to minimize its damage to Citrus spp., integrated pest management (IPM) approach, including fungicide chemicals and resistant cultivars, is necessary. Therefore, in this study we tried to evaluate tolerance of yuzu cultivars and its related species against yuzu Phytophthora. Trifoliate orange was evaluated as a susceptible host to yuzu Phytophthora by both mycelial growth onto extract media and immature fruit inoculation. However, in zoospores spray-inoculation on 2-year-old cuttings tree, trifoliate orange appeared to have a resistant property as showing less than 6% diseased leaf rate. Among yuzu cultivars only 'Namhae No. 1' appeared resistant property against both P. nicotianae and P. citrophthora. The 'Namhae No. 1' showed 5.7% and 10.6% diseased leaf ratio by P. nicotianae and P. citrophthora, respectively. Clearly, in order to reduce damages caused by two yuzu Phytophthora, we suggest that growers may utilize a trifoliate orange as a rootstock and 'Namhae No. 1' as a scion for fruit production.

• 한국식물병리학회지
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• 제10권3호
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• pp.169-174
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• 1994

A new unidentified pear leaf spot disease presumed to first occur in the late 1970's has recently become prevalent over the pear growing areas, and caused the greatest problem for pear production in Korea. The disease began to develop on pear leaves at mid- to late May, peaked at mid- to late une, but stopped further development until September in cool climate. Leaf lesions are 0.9∼2.5 mm in diam., oval or irregular to rectangular in shape, first appeared reddish purple, later changed to dark brown, and to whitish grey in the late season. Lesions were limited to appear only on the mature, hardened leaves, initially from leaf margin or near the leaf veins, and later scattered over the leaf surface. Individual lesions usually did not enlarge, but often coalesced each other, commonly causing shot holes and eventual early falling. The disease was most severe on the major pear cultivars Niitaka and Okusankichi ranged with 4 to 100% infections in trees, depending on the orchards, but not on the cultivar Chojuro. Damages from the disease included lower fruit weight, and higher acid and less sugar content in fruits, resulting in lowering the overall fruit quality. Etiology of the disease including identification of the causal organism is in a separate paper.

• 로봇학회논문지
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• 제15권2호
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• pp.107-114
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• 2020

In robotic harvesting, a gripper to manipulate the fruits needs to be attached to the robot system. We proposed a flexible robot gripper that can actively respond to the shape of an object such as fruits in the previous work. However, we found that there is a possibility of not being reliably gripped when the object slides during contact with a finger. In this paper, the improved gripper design is proposed to fundamentally solve the problems of the previous gripper. The position of the finger and the maximum closed position are changed, and the design improvement is performed to increase the grip stability by changing the installation angle of the link portion of the finger. Based on the improved design, a modified gripper is fabricated by 3-D printing, and then gripping experiments are performed on spherical object and fruit model object. It is shown that the gripper can stably grip the objects without excessive bending of the finger link of the gripper. The contact pressure between the finger and the surface of the object is measured, and it is verified that it is a sufficiently small pressure that does not cause damage to the fruit. Therefore, the proposed gripper is expected to be successfully applied in harvesting.