• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.2
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• pp.65-73
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• 2016

We estimated the averaged maximum incidences of bacterial canker at suitable sites for kiwifruit cultivation in 2020s and 2050s using D-PSA-K model with RCP4.5 and RCP8.5 climate change scenarios. Though there was a little difference between the estimation using RCP4.5 and that using RCP8.5, the estimated maximum disease incidences were more than 75% at all the suitable sites in Korea except for some southern coastal areas and Jeju island under the assumption that there are a plenty of infections to cause the symptoms. We also analyzed the intermediate and final outputs of D-PSA-K model to find out the trends on the change in disease incidence affected by climate change. Whereas increase of damage to kiwifruit canes in a non-frozen environment caused by bacterial canker was estimated at almost all the suitable sites in both the climate change scenarios, rate of necrosis increase caused by the bacterial canker pathogen in a frozen environment during the last overwintering season was predicted to be reduced at almost all the suitable sites in both the climate change scenarios. Directions of change in estimated maximum incidence varied with sites and scenarios. Whereas the maximum disease incidence at 3.14% of suitable sites for kiwifruit cultivation in 2020s under RCP4.5 scenario was estimated to increase by 10% or more in 2050s, the maximum disease incidence at 25.41% of the suitable sites under RCP8.5 scenario was estimated so.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.245-247
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• 1977

Penicillium digitatum SACCARD, P. italicum WEHMER, Botrytis cinerae PERSOON and Sclerotinia sclerotiorum MASSE. were the main storage diseases on the cold injured mandarin at Jeju in 1975. The losses observed through the materials used were $18.3\%$ which consists of $8.1\%$ by diseases and $10.2\%$ by water rot as the result of cold and snow damages at harvest stage in Jeju. The total amount of damages estimated at shipping stage were 915M/T in value of 135 million Won from the rot waste of 675M/T by the end of 1975. Since cold injury is known as the main factor of the fruit rot, shipping and storage process as well as disease control measures are discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.426-435
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• 2020

To determine the damages to waxy corn caused by low temperature weather, we investigated the relationship between the temperature and duration of low temperature treatment and the changes in growth characteristics during the recovery period after the treatments in different growth periods. Growth inhibition started in the low temperature group treated at temperatures below 5℃ for three days. The inhibition ratio (IR) was more than 22% or more in all sample groups. As the treatment duration increased and the Temperature decreased, the growth was more greatly inhibited than that in the control. The IR was the highest at 27% or more in the 2nd leaf stage group treated at below 5℃ for 5 days. The IR was in the order of 2nd leaf stage > 1st leaf stage > coleoptile. The IR during recovery was the highest in the 2nd leaf stage group treated at -3℃ degree for 7 days, nd the values were 82% and 98% for NDVI and Fv/Fm, respectively. Especially, all groups treated at -3℃ showed either no changes or decreases in the growth characteristics. As a result, growth inhibition increased as the temperature decreased, and as the duration of the low temperature increased. The degree of damage was in the order of 2nd leaf stage > 1st leaf stage > coleoptile. All early seedlings stopped growing and withered when exposed to temperatures at or below -3℃ for 3 days or more.

• Food Science and Preservation
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• v.8 no.4
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• pp.351-355
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• 2001

This study was carried out to examine the of quality on the dried Omija according to its package materials and storage plates. The changes of moisture contents, anthocyanin content, molds damage rates, and color values were measured during storage. In the sealing up by the P.E file, the moisture contents of the dried Omija had just a little differences among the storage places, but in the gauze bag remarkably as the storage period goes on, especially in this case, 8 months later since the storage in the cool chamber, the damage rates of the dried Omija by the mold was 9.0%, twice as much as in the indoor bag packaging it was increasand after 10 months, that was lather high in the indoor and warehouse. The anthocyanin content of the dried Omija after the storage of 10 months was the highest at 0.05mm black P.E film package in the cool chamber, which was 55.7 mg/100g, but in the indoor and warehouse 39.7, 45.0mg/100g, respectively. These results show thats the storage conditions had an important effect on the quality of the dried Omija during the long-term storage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.184-187
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• 2004

In case of a semi-forcing culture for vegetable perilla, the following research results on the effect of black polyethylene mulching, the optimum sowing season, and the seedling stand improvement method were drawn. Soil temperature was higher and the emergence was faster in a black polyethylene mulching culture than in a non-mulching culture. However, the mature was late, the main stem were larger, and the seed yield, as well as the leaf yield, was greater in a mulching culture than in a non-mulching culture. Considering growth and chilling injury, the stable sowing season of vegetable perilla was judged to be the early in January. The covering materials for improvement of the seedling stand can be a non-woven fabric and hyaline polyethylene. However, the non-woven fabric seemed to be quite suitable in view of the stability and convenience of control after the emergence of perilla.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.11a
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• pp.163-171
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• 2001

시설 원예작물의 겨울철 온도환경 관리에 대한 연구는 난방비 절약을 위한 저온관리 한계온도 구명(Tanaka 등, 1986), 또는 근권부 온도 조절에 의한 작물의 생산성 증진 연구와 같은 실용적 측면의 연구가 많이 수행된 바 있다(Fujie와 Saidou, 1983). 그러나 시설의 온풍기 고장 또는 정전 등으로 작물이 생육한계 온도이하의 저온상태에서 장시간 경과 되었을 때 나타나는 여러가지의 생리적인 장해나 피해에 대한 연구는 매우 적은 실정이다(Reyes와 Jennings, 1994). (중략)

• The Korea Swine Journal
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• v.29 no.11 s.339
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• pp.184-188
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• 2007

시장 개방의 가속화로 어려움이 한층 가중되고 있는 요즘 한.미 자유무역협정(FTA) 협상 타결에 이어 유럽연합(EU)과의 FTA 협상이 진행 중이다. 이처럼 거센 시장 개방 환경에서 살아남으려면 우리 양돈산업의 경쟁력 향상이 절대적으로 요구된다. 이를 위해서는 철저한 사양관리와 환기관리를 통한 폐사율의 감소와 생산성 향상은 우리 농가들에게 필수적으로 요구되고 있는 항목이다. 저온진입기, 즉 동절기로 진입하는 요즘에는 보온으로 인한 환기불량과 추위로 인한 생체기능이 떨어지기 때문에 전반적인 질병에 대한 저항력이 감소되어 질병 발생 가능성은 어느 계절보다 크다. 양돈농가의 생산성 저하로 인한 경제적 피해를 최소하화기 위해서는 돼지의 호흡기질병 예방을 철저히 하고 농장의 단열과 환기시설 점검을 통한 효율적인 대책에 만전을 기해야 성공적인 양돈을 기대 할 수 있을 것이다. 높은 폐사율을 극복하고 부족한 환기관리와 시설은 꼼꼼한 컨설팅으로 보완하여 생산성 향상에 노력하고 있는 충남 당진 순성농장(대표 박중호)을 찾아가 보았다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.252-261
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• 2003

Although the young spike of barley (Hordeum vulgare L.) or wheat (Triticum aestivum L.) is known as the most susceptible part to spring cold injury, the risk of cold injury is apt to be ignored in most breeding program due to the importance of early maturity. Based on these aspects, the types and inducing time, temperature conditions for induction and effects of cold injury on growth and yield in this study were investigated under greenhouse and field conditions through three years (1997-1999). In natural condition, low temperature around -2.4∼$-10.2^{\circ}C$ caused the death of plant. Several cold injury types such as partial degeneration of spike, partial discoloration of leaf, spike and awn, discoloration of culm and white spike were observed at low temperature around $-3.1^{\circ}C$. Low temperature around -2.4∼$-8.6^{\circ}C$ and 1.3-$7.6^{\circ}C$ caused degeneration and sterility of spike, respectively. Most materials were prepared to the spikelet foundation stage, spikelet differentiation stage, development stage of flower organ, booting stage and heading stage, which were known having risk for cold injury in field condition. Although most of the controlled stages were sensitive to the induced low temperature, booting stage was the most sensitive stage for cold injury. All of growth stages which were treated-heading stage, booting stage, development stage of flower organ, spikelet differentiation stage, spikelet foundation stage-were responded to low temperature treatment but the symptoms revealed were very specific according to the growth stages. Ears of plant in heading stage were discolored to white. Ears of plant in booting stage were degenerated in all or part of one. Plants in spikelet differentiation stage were sterile in all or part of one. When tried to detect the specific differences between normal and cold injured plants in appearance, spike length, distance between spike and flag leaf and the first internode length could be the critical points for occurrence of spike death caused by cold injury. In barley, the elongation of spike was stopped on 3.2cm after occurrence of spike degeneration, 4.7cm after occurrence of partial degeneration of spike, 5.0cm after occurrence of white spike. In wheat, it was stopped on 1.6cm after occurrence of stem death, 3.3cm after occurrence of spike degeneration, 8.3cm after occurrence of partial degeneration of spike, 8.1cm after occurrence of white spike, 7.5cm after partial discoloration of leaf and 9.3cm after partial discoloration of spike. The obtained results from low temperature treatment induced in growth chamber were similar to the field experiment, Beacuse the death of spikes was more when low temperature was treated two times than one times, the temperature should be upgrade to -3$^{\circ}C$ in order to get the same condition with field test.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.98-106
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• 1987

The effect of carbofuran (2, 3-Dihydro-2,2-dimethyl-benzofuran-7-ylmethyl carbamate) on rice growth was evaluated as a direct growth stimulant of rice. For this, several laboratory and field trials conducted from 1981 to 1986 at the Yeongnam Crop Experiment Station. Carbofuran solution affected the germination of rice seed. The growth of seminal roots was adversely affected by the increase of carbofuran concentrations while the length of single root became longer with the concentration increment up to 50 ppm. Carbofuran application (0.18g ai/$m^2$) at the rice nurserybed significantly enhanced the rice growth and recovered from the Low temperature damage. The enhancement effect was more pronounced at the plot that applied carbofuran before rice seeding as soil incorporation than top-dressing. The effect of growth enhancement further extended to transplanted lowland rice. This effect was greater at double cropping area (late of June transplanting) compared to single cropping area (May transplanting). Among important agronomic traits, the increment of panicle number was the most important direct effect for increasing rice grain yield by carbofuran application. Carbofuran application also exhibited the reducing effect against low temperature damage at reductive division stage and at rice heading stage and against submergence damage at booting stage through enhancement of fertile grain ratio, ripening ratio or photosynthetic activity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.1
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• pp.51-58
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• 2014

Freezing hardiness of winter bud and branch of several pear (Pyrus pyrifolia) cultivars according to degree and duration of low temperatures was investigated by sprouting, electrolyte leaching rate and triphenyltetrazolium chloride (TTC). Sprouting rate as infected by degree and duration of low temperature were different between cultivars. The lower temperature, the longer duration, sprouting rate was decreased. Electrolyte leaching rate was showed above 30% at below $-30^{\circ}C$ treatment regardless of cultivars and duration. The lower temperature and the longer duration, Electrolyte leaching rate was increased. Electrolyte leaching rates of Manpungbae, Niitaka and Chuwhangbae at $-30^{\circ}C$ for 9 hours treatment which were observed high sprouting rate, were lower than those of other varieties. Absorbance rates by TTC test at $-21^{\circ}C$ treatment were 66.0 to 96.5% for 6 hours, 49.4 to 91.9% for 9 hours, and 37.3 to 89.4% for 12 hours. Freezing hardiness of pear cultivars at ecodormancy was different according to degree and duration of low temperature treatments.