• 한국작물학회지
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• 제43권3호
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• pp.172-178
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• 1998

Freezing-resistant plants can survive subzero temperatures by withstanding extracellular ice formation. During cold acclimation, their leaves accumulate antifreeze proteins (AFPs) that are secreted into the apoplast and have the ability to modify the normal growth of ice crystals. Three barley, two wheat and two rye cultivars were grown under two different temperature regimes (20/16$^{\circ}C$ and 5/2$^{\circ}C$, day/night). Apoplastic proteins from winter cereals were separated by SDS-PAGE and detected with antisera to AFPs from winter rye. Apoplastic proteins accumulated to much higher levels in cold-acclimated (CA) leaves compared with nonacclimated (NA) ones in winter cereals. After cold acclimation, the protein concentration of apoplastic extracts increased significantly from 0.088 $mgmL^{-1}$ to 0.448 $mgmL^{-1}$, with about 5-fold increment. Also, the apoplastic protein content per gram leaf fresh weight in CA leaves ranged from 31 $\mu\textrm{g}$ $(gFW)^{-1}$ to 120 $\mu\textrm{g}$ $(gFW)^{-1}$ with an averaged value of 77 $\mu\textrm{g}$ $(gFW)^{-1}$, and coefficients of variation of 54.9%. The CA leaves in Musketeer (a Canadian winter rye cultivar) showed the greatest AFPs and antifreeze activity followed by 'Geurumil' (a Korean winter wheat cultivar), and 'Dongbori l' (Korean facultative barley cultivar). The proteins secreted into the wheat leaf apoplast at CA condition were more numerous than those observed in winter rye, where two $\beta$-1,3-glucanase-like proteins (GLPs), two chitinase-like proteins (CLPs) and two thaumatin-like proteins (TLPs) accumulated during cold acclimation. The proteins in barley leaf apoplast at CA conditions were a little different from those in wheat leaves. The AFPs were various among and within species. More freezing-resistant cultivars had more clear and numerous bands than less freezing-resistant ones. The high determination coefficient ($R^2$ =91 %) between freezing resistance and AFPs per gram leaf fresh weight indicated that the amount of AFPs was highly related to freezing resistance in winter cereal crops.

• BMB Reports
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• 제33권5호
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• pp.385-390
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• 2000

Overwintering plants should survive the various biotic and abiotic stresses that occur during winter. Previous studies indicated that active oxygen species are involved in freezing, dehydration, anoxia and pathogen infections. As the importance of the events that occur in the intercellular compartment became apparent in disease resistance, we examined the nature of intercellular antioxidant enzymes in order to access their possible involvement in the winter hardiness of barley. The levels of intercellular peroxidase, catalase, and SOD activities on the unit protein basis were 394, 18, and 9% of those of cellular activities, respectively. Major intercellular peroxidase isoforms consisted of four neutrals and four basic forms; whereas major cellular isoforms were two basic forms. Out of the two major catalase isoforms a higher molecular weight form was predominantly abundant in both cellular and intercellular compartments. Among the five major cellular SOD isoforms, three were also present in the intercellular compartment. The presence of substantial amounts of intercellular antioxidant enzymes in overwintering barley leaves may suggest the involvement of these enzymes in the tolerance mechanism to the various stresses that occur during winter.

• 한국초지조사료학회지
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• 제43권3호
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• pp.156-161
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• 2023

This study was conducted to determine the appropriate seeding dates by verifying the difference in winter survival and productivity of alfalfa according to fall sowing dates in the central area of South Korea. The experiment was conducted for 2 years (2020 and 2021) at the field in the Department of Animal Resources Development, NIAS located in Cheonan. Sowing dates started from September 18 to November 8 with 10 days of intervals during 2020 and 2021; SO1 (September 18), SO2 (September 28), SO3 (October 8), SO4 (October 18), SO5 (October 28), and SO6 (November 8). After sowing, the winter survival rate was measured in the spring of the following year, and the dry matter yield was measured by harvesting at 10% flowering and harvesting five times a year. SO6 failed to winter survival, and SO5 also had a lower winter survival rate than SO1~4 (p<0.05). The average annual dry matter yield of alfalfa linearly decreased with delaying sowing dates (p<0.05). The feed value did not differ in the same year by delaying the sowing date in the same year. These results suggest that sowing date should be started before October 18 to increase winter survival and productivity of alfalfa in the central area of South Korea.

• Animal cells and systems
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• 제7권2호
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• pp.111-117
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• 2003

Ecological aspects of Cryptocercus kyebangensis life history were investigated via laboratory rearing and field observations. The number of antennal segments and head width were used to classify the first four instars. The results, which combine both the field collection and the laboratory rearing, indicate that eleven instars occur in C. kyebangensis. It supports the proposal on the number of instars of Park and Choe (2003c) based on field collections. A total of 388 nymps from 13 colonies were collected prior to winter to investigate overwintering stages. Of them,4％ (n = 17) were the second instars, 57％ (n = 220) were the third instars, and 39％ (n = 151) were the fourth instars, respectively. Thus, most of them overwinter in the third or fourth instars. The results indicate that young nymphs of C. kyebangensis have to reach at least 3rd or 4th instar to survive low temperature environment of winter. According to seasonal dynamics of populations, C. kyebangensis reaches adulthood in the summer of the fourth or fifth year (4-5 yr span) after their birth.

• 한국시스템다이내믹스연구
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• 제16권2호
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• pp.53-74
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• 2015

Nutria(Myocastor coypus) is one of the most notorious invasive species in many countries. The Nutria's original range was South America like Brazil, Chile and Argentina. But it has been introduced to North America, Europe, Africa, and Asia including Korea, by fur ranchers. Like most invasive and disturbing species, nutria not only destroys habitats but also impacts many native species throughout most of its range with destructive feeding behavior. The purpose of this study is to investigate the dynamics of survival mechanism, population increase and spatial distribution, and eradication effect of Nutria on Nakdong River Area with the systems thinking. The result of this study revealed that Nutria can survive during winter with the behavior that the colder the winter was, the more deeply it burrowed. Further, the study uncovered the dynamics that nutria has survived more and more strongly during the extreme cold winter in almost every region and their population has increased dramatically as a result of the uncontrolled reproduction. Finally, the result showed that the action delay in eradicating Nutria, which was originated from the information delay of perception of nutria's survival and reproduction structure, reinforced the spread of Nutria across the nation.

• 한국초지조사료학회지
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• 제36권4호
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• pp.340-343
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• 2016

The present study investigated the effects of different seeding rates on growth characteristics and seed productivity of the "Kowinearly" cultivar of Italian ryegrass (Lolium multiflorum Lam.) in paddy fields. Sowing Kowinearly in paddy fields under growing rice at the rates of 20, 30, 40, and 50 kg/ha resulted in seed yields of 1.57, 1.92, 2.06, and 2.09 ton/ha, respectively. Seed yield of Kowinearly was the highest at a seeding rate of 50 kg/ha (p<0.05), at which the cultivar was able to survive in winter and the weed ratio was low. Under these conditions, most growth characteristics such as winter survival (85%), weed ratio (10%), stems per square meter (1,006) were superior than those sown at other seeding rates (p<0.05). In addition, it has been reported that the economic efficiency of the 50 kg/ha seeding rate was higher than that of the other seeding rates.

• 농업과학연구
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• 제43권4호
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• pp.560-566
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• 2016

Imports of genetically modified (GM) soybeans (Glycine max) for food or feed consumption in Korea have been increasing. Although the cultivation of GM soybeans has not yet been allowed in Korea, the number of field tests for GM soybeans has also been rising. This study was conducted to investigate whether herbicide tolerant GM soybean can survive and persist in uncultivated environments when they escape from transportation routes or from isolated fields. Seeds of GM and non-GM soybeans and wild soybeans (Glycine soja) were buried in 2 and 15 cm soil depths and their viability was examined after 1, 2, 6, and 10 months. GM and non-GM soybean seeds completely lost their viability within six months of burial, whereas seeds of wild soybean maintained their viability during the study period. Seeds of soybean and wild soybeans that were sown on the soil surface germinated and grew to vegetative cotyledon stage. Seedlings of GM and non-GM soybean did not compete well with weeds, including Cerastium glomeratum, Alopecurus aequalis var. amurensis, Capsella bursa-pastoris, Conyza canadensis, Stellaria aquatica, and Erigeron annuus. Also, GM soybean did not survive through winter. However, wild soybeans competed well with the weeds and became dominant in August. Herbicide tolerant GM soybean is unlikely to persist under uncultivated environments and to become weeds.

• 한국응용곤충학회지
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• 제53권3호
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• pp.287-293
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• 2014

팥나방 (Matsumuraeses phaseoli) (나비목: 잎말이나방과)은 한국에서 팥 (Vigna angularis)과 녹두 (Vigna radiata)의 꽃과 꼬투리를 가해하는 주요 해충의 하나인데, 수원지방에서 이 곤충의 발육 특성과 월동태를 추정할 목적으로 야외 ($37^{\circ}$16'N $126^{\circ}$59'E 35ASL) 조건에서 인공사육을 통해 발육과정이 관찰되었다. 갓 부화한 유충 집단들은 약 14일 간격으로 인공사료를 이용하여 1년 이상 야외에서 사육되었는데, 봄에서 고온인 여름철로 감에 따라 발육기간이 짧아지고, 가을철로 감에 따라 다시 길어지는 경향이었다. 유충 혹은 번데기 발육에서 여름철 하면 현상은 발견되지 않았다. 2008년 10월 8일 사육이 시작된 집단은 번데기 상태로 월동하였는데, 6%의 생존율을 보이며 이듬해 4월말 우화하였다. 10월 23일에 사육이 시작된 집단은 노숙유충태로 월동하였는데, 이듬해 4월말 용화하여, 5월 초중순에 2%의 최종 생존율을 보이며 우화하였다. 한편 실내에서 사육되어 5령까지 발육된 유충들을 11월과 2월 사이에 야외로 옮겨 사육하였을 때, 생존하는 개체들은 발견하지 못하였다. 항온조건 ($25^{\circ}C$, 15L:9D)에서 갓 산란된 알을 11월과 12월 중에 야외로 옮겨 유지하였을 때, 월동하여 부화하는 알은 발견되지 않았다. 또 항온조건에서 갓 우화한 성충들을 11월과 12월 중 야외로 옮겨 사육하였을 때, 모두 사망하였다. 이 결과로 팥나방은 한국의 수원지방에서 10월 중 부화한 유충들이 유충과 번데기로 월동할 수 있는 것으로 추정되었다.

• 한국균학회지
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• 제5권1호
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• pp.33-37
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• 1977

포장(圃場)에서 키다리병(病)에 걸린 줄기와 종자(種子)로 부터 얻은 자낭각이 어느 종류(種類)의 Gibberella에 존재(存在)하며, 수확후(收穫後)에 얻은 자낭각의 생존(生存)여부를 조사(調査)하기 위하여 처리한 결과(結果)는 다음과 같다. 1. 종자소독(種子消毒)을 하지 않은 포장(圃場)에서 키다리병(病)의 이병율(罹病率)은 평균(平均) 12%이었다. 2. 수확전(收穫前)에 얻은 자낭각은 키다리병의 자낭각이 적미병의 자낭각보다 많았으나 종자(種子)나 봄에 채집한 자낭각은 거의 적미병에 있었다. 3. 키다리병에 이병된 벼에서 채종한 종자(種子)에서 키다리병, 적미병, Ophiobolus sp.는 10, 25, 8%로 나타났으며 이병(罹病)된 줄기로부터 얻은 포자(胞子)로 접종(接種)한 종자(種子)에서는 3, 10, 2%로 나타났다. 4. 적미병자낭각을 야외 땅속 실내 집눌속에 놓고 5개월이 지난다음 생존(生存)여부를 조사(調査)한 결과(結果) 야외에 놓은 것만 발아하지 않았다.

• 한국식물병리학회지
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• 제2권1호
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• pp.17-21
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• 1986

현재 벼오갈병의 발생한계지역인 울진에서 바이러스 보독 끝동매미충의 약충이 포장상태에서 월동할 수 없었다. 매개충의 발생소장과 벼오갈병 발병과의 관계를 보면, 매채충은 년 5회, 발병은 년 3회의 최성기를 나타내었고, 월동세대의 성충, 2세대약충 및 3세대의 약충이 주로 바이러스 전염의 요인이 되었다. 상습발병지의 밀양 30호 재배포장에서 재생병에 $22.4\~26.8\%$의 발병주율을 나타냈으며, 월동에 들어갈 약충이 $11\~30$일간 재생이병주를 흡즙한 결과 이듬해의 바이러스 보독월동충율이 $13.0\~18.2\%$나 되었다. 벼오갈병에 감염된 추파 보리는 월동 생존할 수 없어, 감염식물에서의 월동이 불가능하였다.