• 한국작물학회지
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• 제37권3호
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• pp.288-298
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• 1992

Since the major important factors limiting plant growth and crop productivity are environmental stresses, of which low temperature is the most serious. It has been well known that many physiological processes are alterant in response to the environmental stress. With regard to the relationship between plant hormones and the regulation of chilling tolerance in rice seedlings, the major physiological roles of plant hormones: abscisic acid, ethylene and polyamines are evaluated and discussed in this paper. Rice seedlings were grown in culture solution to examine the effect of such plant hormones on physiological characters related to chilling tolerance and also to compare the different responses among tested cultivars. Intact seedlings about 14 day-old were chilled at conditions of 5$^{\circ}C$ and 80% relative humidity for various period. Cis-(＋)-ABA content was measured by the indirect ELISA technique. Polyamine content and ethylene production in leaves were determined by means of HPLC and GC respectively. Chilling damage of seedlings was evaluated by electrolyte leakage, TTC viability assay or servival test. Our experiment results described here demonstrated the physiological functions of ABA, ethylene, and polyamines related to the regulation of chilling tolerance in rice seedlings. Levels of cis-(＋)-ABA in leaves or xylem sap of rice seedlings increased rapidly in response to 5$^{\circ}C$ treatment. The tolerant cultivars had significant higher level of endogenous ABA than the sensitive ones. The ($\pm$)-ABA pretreatment for 48 h increased the chilling tolerance of the sensitive indica cultivar. One possible function of abscisic acid is the adjustment of plants to avoid chilling-induced water stress. Accumulation of proline and other compatible solutes is assumed to be another factor in the prevention of chilling injuies by abscisic acid. In addition, the expression of ABA-responsive gene is reported in some plants and may be involving in the acclimation to low temperature. Ethylene and its immediate precusor, 1-amincyclopropane-1-carboxylic acid(ACC) increased significantly after 5$^{\circ}C$ treatment. The activity of ACC synthase which converts S-adenosylmethionine (SAM) to ACC enhanced earlier than the increase of ethylene and ACC. Low temperature increased ACC synthase activity, whereas prolonged chilling treatment damaged the conversion of ACC to ethylene. It was shown that application of Ethphon was beneficial to recovering from chilling injury in rice seedlings. However, the physiological functions of chilling-induced ethylene are still unclear. Polyamines are thought to be a potential plant hormone and may be involving in the regulation of chilling response. Results indicated that chilling treatment induced a remarkable increase of polyamines, especially putrescine content in rice seedlings. The relative higher putrescine content was found in chilling-tolerant cultivar and the maximal level of enhanced putrescine in shoot of chilling cultivar(TNG. 67) was about 8 folds of controls at two days after chilling. The accumulation of polyamines may protect membrane structure or buffer ionic imbalance from chilling damage. Stress physiology is a rapidly expanding field. Plant growth regulators that improve tolerance to low temperature may affect stress protein production. The molecular or gene approaches will help us to elucidate the functions of plant hormones related to the regulation of chilling tolerance in plants in the near future.

• 생물환경조절학회지
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• 제15권4호
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• pp.390-395
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• 2006

토마토 유묘의 생육에 미치는 glycine betaine의 엽면처리 효과를 분석한 결과, 초장이나 건물중 등의 생육이 대조구인 증류수 처리에 비해 촉진되는 경향을 보였으며 25mM glycine betaine 처리가 가장 좋았다. 저온스트레스 하에서 삼투조절 역할을 하는 가용성 당과 proline의 축적량이 증류수 처리에 비해 glycine betaine처리에서 낮은 경향을 보여 외부에서 엽면 처리한 glycine betaine이 삼투조절 역할을 한 것으로 판단되었으며 이러한 결과는 수용성 단백질과 유리 아미노산의 축적 양상에서도 잘 반영되었다. 이상의 결과로 보아 glycine betaine의 엽면 처리는 저온기 시설 토마토 재배 시 야간 저온장해를 극복할 수 있는 방법으로서 이용 가능성이 있을 것으로 사료된다.

• 한국작물학회지
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• 제42권4호
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• pp.384-391
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• 1997

산형과 약용작물인 시호의 재배에서 나타나는 문제점의 하나는 발아 불량에 의한 입묘 실패라할 수 있다. 따라서 파종 전 종자에 손쉽게 처리할 수 있는 방법을 모색하여 입묘율을 증진할 수 있는가에 대한 정보를 얻고자 재래시호와 최근에 육성된 장수시호를 공시하여 치상 전의 $GA_3$ 처리 [0(물), 0.01, 0.1mM (농도) : 2, 4, 8일 (기간)] 또는 저온처리기간 (0, 4, 8주)에 가하여지는 광질처리 (적색광, 백색광, 암)가 발아율에 미치는 영향을 조사하였던 바 그 결과를 요약하면 다음과 같다. 1. 요인별 평균 발아율은 공시품종, GA$_3$ 침지기간 또는 광질처리에 의하여 영향을 받는 것으로 분석되었던 반면, 물과 $GA_3$ 처리 또는 $GA_3$ 처리농도간에는 차이가 없었다. 2. 물로 침지하면서 광질처리를 가할 경우 평균발아율은 장수시호보다 재래시호에서 높았고, 2~4일간 침지하거나 침지과정 중 적색광을 처리할 경우 발아가 향상ㆍ촉진되는 경향을 보였다. 3. 공시품종별 발아율에서 재래시호는 광질처리간에 차이가 없었으나, 2일간 물로 침지하면서 광질처리를 가할 경우 발아율이 가장 높았던 반면, 장수시호는 4일간 침지하면서 적색광을 가할 경우 가장 높았다. 4. 치상 전 저온처리를 가하지 않는 상태에서 광질처리를 할 경우 발아율이 가장 높았으며 발아과정에서는 암상태보다는 백색광에서 발아율이 향상되었다. 5. 저온처리를 가하지 않은 경우 평균 발아율은 광질처리간 차이가 없고, 장수시호보다는 재래시호에서 높다고 할지라도 장수시호는 2일간 물에 침지시킨 후 발아과정에서 빛이 있어야 발아율이 향상될 것으로 보인다.

• 생명과학회지
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• 제12권6호
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• pp.694-699
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• 2002

본 연구는 파종전 종자처리에 의해 박 종자의 발아율을 최대한 향상시킬 수 있는 방법을 강구하고자 종피연화, 세척, 저온 및 건조 중 적색광 처리가 발아에 미치는 영향을 조사하였으며 그 결과를 요약하면 다음과 같다. 1) 종피연화는 염기성인 KOH 또는 NaOH로 처리하는 것보다 산성인 acetone과 acetonitrile 10% 용액에 1시간 처리하였을 때 발아율이 증가되고 발아가 촉진되는 것으로 나타났다. 2) Acetone으로 종피연화 시킨 종자는 이후에 행하여지는 저온처리의 영향을 적게 받는 반면, KOH로 종피연화 시킨 종자는 저온처리가 행해지지 않을 경우 발아가 현저히 억제되었다. 3) 종피연화 후 흐르는 수돗물로 1시간 세척시킨 종자의 발아율은 세척하지 않은 것보다 높았다. 4) 종피연화, 세척 및 저온처리를 경과가 이루어진 종자는 건조과정에서 암처리보다는 적색광을 처리하였을 경우 발아율이 높았다.

• Journal of Microbiology and Biotechnology
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• 제32권5호
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• pp.582-593
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• 2022

Among abiotic stresses in plants, drought and chilling stresses reduce the supply of moisture to plant tissues, inhibit photosynthesis, and severely reduce plant growth and yield. Thus, the application of water stress-tolerant agents can be a useful strategy to maintain plant growth under abiotic stresses. This study assessed the effect of exogenous bio-based 2,3-butanediol (BDO) application on drought and chilling response in tomato and turfgrass, and expression levels of several plant signaling pathway-related gene transcripts. Bio-based 2,3-BDOs were formulated to levo-2,3-BDO 0.9% soluble concentrate (levo 0.9% SL) and meso-2,3-BDO 9% SL (meso 9% SL). Under drought and chilling stress conditions, the application of levo 0.9% SL in creeping bentgrass and meso 9% SL in tomato plants significantly reduced the deleterious effects of abiotic stresses. Interestingly, pretreatment with levo-2,3-BDO in creeping bentgrass and meso-2,3-BDO in tomato plants enhanced JA and SA signaling pathway-related gene transcript expression levels in different ways. In addition, all tomato plants treated with acibenzolar-S-methyl (as a positive control) withered completely under chilling stress, whereas 2,3-BDO-treated tomato plants exhibited excellent cold tolerance. According to our findings, bio-based 2,3-BDO isomers as sustainable water stress-tolerant agents, levo- and meso-2,3-BDOs, could enhance tolerance to drought and/or chilling stresses in various plants through somewhat different molecular activities without any side effects.

• 한국식품영양과학회지
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• 제27권2호
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• pp.207-213
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• 1998

These experiments were carried out to investigate the effects of electrical stimulation(ES) and delayed chilling (DC) on the quality characteristics of Hanwoo beef. The left half carcass was treated with ES(550V, 90sec)within postmortem 30min. The electrical stimulated half carcass was subjected to chilling at 16$^{\circ}C$ for 24hr, and then stored at 2$\pm$2$^{\circ}C$ for 15days (ESDC). The right half carcass was stored at 2$\pm$2$^{\circ}C$ for 15 days (NES). ESDC showed a rapid pH fall and tended to reach to pH5.54 at postmortem 2 hrs. But, there was no consistent effect of electrical stimulation and delayed chilling on meat color, cooking loss and water holding capacity. Myofibril fragmentation index was higher than that of NES during storage. ESDC showed lower shear force value and strength consistently than NES. SDS-PAGE band patterns of myofibrils showed the rapid breakdown of troponin T and troponin I band in ESDC, compared with NES, and revealed the specific band below myosin light chain-2 pattern in ESDC.

• Asian-Australasian Journal of Animal Sciences
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• 제20권2호
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• pp.257-262
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• 2007

The current study was conducted to investigate the optimum stunning voltage and chilling regime with emphasis on reduction in pale, soft and exudative (PSE) pork. The experiments were conducted at seven Korean major pig abattoirs using a total of 91,082 industrial population. Frequencies of PSE meat was found to be significantly (p<0.05) increased as stunning voltage was elevated from 220-240 (13.14%), 250-280 (29.32%) to 430 volts (36.74%). Chilling methods after slaughter, either with cold water showing or rapid chilling reduced PSE meat by 22% compared to a classic chiller-based slow chilling regime. The current study also revealed that chiller temperature during the first 90 minutes had a significant (p<0.001) effect on PSE incidences. Pigs chilled between -5 to $7^{\circ}C$ resulted in the lowest PSE meat (17.8%), followed by higher than $7^{\circ}C$ (21.3%) and lower than $-5^{\circ}C$ (37.5%). The current data implies that low voltage stunning method (eg., 220-240 volts), followed by rapid chilling regime, maintaining chiller temperature between approximately -5 to $7^{\circ}C$ could reduce PSE incidences.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.71-80
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• 2005

Effects of low temperature ($8^{\circ}C$) on the hydraulic conductivity of young roots of a chilling-sensitive (cucumber; Cucumis sativus L.) and a chilling-resistant (figleaf gourd; Cucurbita ficifolia Bouche) crop have been measured at the levels of whole root systems (root hydraulic conductivity, $Lp_r$) and of individual cortical cells (cell hydraulic conductivity, Lp). In figleaf gourd, there was a reduction only in hydrostatic $Lp_r$ but not in osmotic $Lp_r$ suggesting that the activity of water channels was not much affected by low root temperature (LRT)treatment in this species. Changes in cell Lp in response to chilling and recovery were similar asroot level, although they were more intense at the root level. Roots of figleaf gourd recovered better from LRT treatment than those of cucumber. In figleaf gourd, recovery (both at the root and cell level) often resulted in Lp and $Lp_r$ values which were even bigger than the original, i.e. there was an overshoot in hydraulic conductivity. These effects were larger forosmotic (representing the cell-to-cell passage of water) than for hydrostatic $Lp_r$. After a short term (1 d) exposure to $8\;^{\circ}C$ followed by 1 d at $20\;^{\circ}C$, hydrostatic $Lp_r$ of cucumber nearly recovered and that of figleaf gourd still remained higher due to the overshoot. On the contrary, osmotic $Lp_r$ and cell Lp in both species remained high by a factor of 3 as compared to the control, possibly due to an increased activity of water channels. After pre-conditioning of roots at LRT, increased hydraulic conductivitywas completely inhibited by $HgCl_2$ at both the root and cell levels. Different from figleaf gourd, recovery from chilling was not complete in cucumber after longer exposure to LRT. It is concluded that at LRT, both changes in the activity of aquaporins and alterations of root anatomy determine the water uptake in both species. To better understand the aquaporin function in plants under various stress conditions, we examined the transgenic Arabidopsisand tobacco plants that constitutively overexpress ArabidopsisPIP1;4 or PIP2;5 under various abiotic stress conditions. No significant differences in growth rates were found between the transgenic and wild-type plants under favorable growth conditions. By contrast, overexpression of PIP1;4 or PIP2;5 had a negative effect on seed germination and seedling growth under drought stress, whereas it had a positive effect under cold stress and no effect under salt stress. Measurement of water transport by cell pressure probe revealed that these observed phenotypes under different stress conditions were closely correlated with the ability of water transport by each aquaporin in the transgenic plants. Together, our results demonstrate that PIP-type aquaporins play roles in seed germination, seedling growth, and stress response of Arabidopsis and tobacco plants under various stress conditions, and emphasize the importance of a single aquaporin-mediated water transport in these cellular processes.

• 원예과학기술지
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• 제29권2호
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• pp.87-94
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• 2011

본 연구에서는 관상가치가 높은 5종의 자생나리에 있어서 조직배양을 통해 획득한 소인경의 휴면타파 및 비대를 위한 저온 및 온탕처리 효과를 구명하기 위해 실시되었다. 솔나리(L. cernuum), 섬말나리(L. hansonii), 민섬말나리(L. hansonii for. mutatum), 중나리(L. leichtlinii), 하늘말나리(L. tsingtauense)의 소인경을 $4^{\circ}C$에서 0, 4, 8주 저온처리하거나 $35^{\circ}C$의 증류수 또는 $100mg{\cdot}L^{-1}$의 $GA_3$와 $GA_{4+7}$ 용액으로 2시간 온탕처리를 하였는데, 저온과 온탕처리는 처리의 선후를 달리하면서 순차적으로 처리한 후 $20^{\circ}C$의 유리온실에서 맹아 및 비대 양상을 조사하였다. 자생나리 5종 모두 기내 소인경은 모두 휴면에 돌입하여 저온 또는 온탕처리 없이는 맹아하지 않았다. 휴면타파를 위한 온탕처리에는 5종 모두 $GA_{4+7}$이 55-96%까지 맹아를 유도한 반면, 증류수나 $GA_3$ 용액은 거의 효과가 없었다. 솔나리와 중나리는 4주간의 저온처리만으로도 50-70%의 맹아를 유도한 반면, 섬말나리, 민섬말나리의 맹아에는 8주간의 저온처리가 필요했다. 온탕과 저온의 연속처리는 맹아 유도에 상승효과를 주었는데, 솔나리와 섬말나리에서 $GA_{4+7}$ 온탕처리 후 4주 저온처리한 것이 역순의 처리보다 맹아를 35-45% 촉진시켰으며, 맹아소요일수도 3-9일까지 앞당겼다. 구근의 비대는 맹아가 촉진된 처리구에서 증가된 경향이었다. 신초는 솔나리에서만 출현하였는데, $GA_{4+7}$ 온탕처리와 저온처리에서 효과적이었으며, 특히 $GA_{4+7}$ 온탕처리 후 저온 8주 처리에서 신초 출현률이 가장 높게 나타났다. 이상의 결과를 종합할 때, 맹아 및 인경비대를 위해 가장 효과적인 휴면타파법은 섬말나리, 민섬말나리와 중나리의 경우에는 $GA_{4+7}$온탕처리 후 4주 저온처리였고, 솔나리와 하늘말나리에서는 $GA_{4+7}$ 온탕처리 후 8주 저온처리구였다.

• 한국식품위생안전성학회지
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• 제3권1호
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• pp.27-36
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• 1988

사람과 동물에 장염을 일으키는 원인균으로서 식품위생학적으로 새로이 문제시 되고 있는 Campylobacter jujuni의 독장에서의 오염원과 오염경로 등을 조사하기 위하여 닭의 분변, 냉각전·후의 계육, 냉각수 , 내장적출용칼을 실험대상으로 하여, 본 균을 분리 동정하고 , 분리균의 생물형, 혈청형등을 조사한 바 다음과 같은 결과를 얻었다. 1. 각 도계공정별로 분리한 82주의 Campylobacter jujuni 는 닭의 분변으로부터 34.4%, 냉각후 계육 55.0% 냉각수 60.0%, 내장적출용칼로부터 45.0%의 불리율을 나타내었다. 2. 분리한 Campylobacter jujuni 균주의 생물형은 biotype I이 78.1%, biotype II가 21.9%이었으며, biotype III와 IV에 속하는 균주는 없었다. 3. 분리균 82주의 Campylobacter jujuni에 대한 혈청형 검사에서 biotype I에속하는 것은 모두 혈청형이 KIO 37 이었으며, biotype II에 속하는 균주의 혈청형은 동정할 수 없었다.