A resveratrol synthase (RS) gene was isolated from peanut (Arachis hypogaea, L. cv. Jinpoong) plants. This gene was placed under the control of the cauliflower mosaic virus 35S promoter (CaMV35S) and introduced into two Korean varieties of potato (Solanum tuberosum L. cvs. Jasim and Jowon) plants by Agrobacterium-mediated gene transfer. Putative transformants were screened by PCR with primers designed from CaMV 35S promoter, NOS terminator and RS gene. Most of selected transgenic potato plants showed the amplification of expected fragments by PCR of genomic DNA with gene-specific primers, while they were absent in untransformed control plants. Expression of the resveratrol synthase gene was also examined by northern blot analysis. The transformants showed a band which was lacking in the control plant, confirming that the introduced gene is transcribed into mRNA in the transformants. The strength of the band, which reflected the level of mRNA expression, differed among the individual transformants. Among the transformants obtained, the highest trans-resveratrol content in the transgenic young leaves of purple-fleshed "Jashim" was 2.11 μgg-1 fresh weight and that in the microtubers in vitro of purple fleshed "Jashim" was 8.31 μgg-1 fresh weight. This amount of resveratrol may have a positive biological effect on human health.

감자 분무경산 소괴경을 심지양액 재배하여 기본식물을 생산할 때, 심지의 배치방법에 따른 씨감자의 생산성 조사하고, 심지를 수평으로 배치할 때 알맞은 심지수를 구명하고자 상자(51×31×20cm , 0.16m2 )당 심지 6개를 수직으로 배치하는 처리와 2~10 개의 심지를 수평으로 배치하는 처리를 두었다. 괴경수는 심지 6개를 수직으로 배치하는 것에 비하여 수평으로 배치함으로 증가하였고 평균괴경중은 감소되어, 괴경수량은 심지 6개의 배치방법에 의하여 영향을 받지 않았다. 상위급씨감자로 사용될 수 있는 5 g 이상의 괴경수는 심지수가 2개에서 6개로 증가됨에 따라 2.8개/주에서 8.0개/주로 증가되었으나, 심지수 6 이상에서는 더 증가되지 않았다. 평균괴경중은 심지수 8개까지 심지수가 많을수록 무거웠으나 심지수 10개에서는 더 이상 무거워지지 않았다. 5 g 이상의 괴경수량은 심지수가 2개에서 6개로 증가됨에 따라 1.81 kg/m2 에서 9.72 kg/m2 으로 크게 증가되었다가, 8개 이상에서는 심지수 증가에 따라 완만히 증가되어 심지 10개 처리구에서는 12.9 kg/m2 이었다. 씨감자 수량과 심지비용, 배지충진 작업의 편리성을 고려할 때 상자당 심지 8개(50.6개/m2 )를 상자의 밑면에 눕혀 수평으로 배치하는 것이 유리할 것으로 판단된다.

Quality changes in fresh-cut potatoes during storage at after treatment with low-temperature blanching and antibrowning agents were studied. Fresh-cut potatoes were treated by dipping for 1.5 min in a browning inhibitor solution containing 0.5% (w/v) ascorbic acid, 0.5% (w/v) citric acid, 0.5% (w/v) sodium chloride, 0.1% (w/v) trehalose, and 0.005% (w/v) biotin, at , with subsequent cooling for 1.5 min and storage at . The browning properties of fresh-cut potatoes were examined by measurement of polyphenol oxidase (PPO) activity and total phenolic content. Changes in quality attributes over a 14-day period were assessed in terms of titratable acidity, pH, water-soluble solid level, and gas analysis at . During storage, PPO activity increased, with the lowest activity seen after about 7 days of storage. Treatment with antibrowning solution at increased visual sensory attributes during storage. Low-temperature blanching in distilled water more effectively inhibited browning compared with exposure to browning inhibitor solution, as assessed after 7 days of storage. Fresh-cut potatoes respired aerobically after different treatments during storage at .

Osmotic stress is one of major limiting factors in crop production. In particular, seasonal drought often causes the secondary disease in the field, resulting in severe reduction in both quality and productivity. Recent efforts have revealed that many genes encoding protein kinases play important roles in osmotic stress signal transduction pathways. Previously, the AtSIK (Arabidopsis thaliana Stress Inducible Kinase) mutants have shown to enhance tolerance to abiotic stresses, accompanying with higher expression of abiotic stress-related genes than did the wild-type plants. In this study, we have transformed potato (cv. Taedong Valley) with the AtSIK expression cassette. Both PCR and RT-PCR using AtSIK-specific primers showed stable integration and expression of the AtSIK gene in individual transgenic lines, respectively. Foliar application of herbicide (Basta®) at commercial application rate (0.3% (v/v)) revealed another evidence of stable gene introduction of T-DNA which includes the bar gene for herbicide resistance. Overexpression of the AtSIK gene under dual CaMV35S promoter increased sensitivity to salt stress (300 mM NaCl), which was demonstrated by the reduction rate of chlorophyll contents in leaves of transgenic potato lines. These results suggest that possible increase of osmotic tolerance in potato plants may be achieved by antisense expression of AtSIK gene.

Ascorbic acid is a great antioxidant and helps protect the body against pollutants. GDP-mannose pyrophosphorylase (GMPase) is a key enzyme in manufacturing GDP-mannose, a glycosyl donor for ascorbate and cell wall biosynthesis as well as for protein glycosylation. In this study, we described molecular cloning of a full-length cDNA from Potato (Solanum tuberosum L. cv. Jasim), using tuber. The cDNA isolated encoded a GDP-mannose pyrophosphrylase. The nucleotide sequence of pGMPC showed about 95%, 89% and 80% homology with S. tuberosum (AF022716), N. tabacum (AB066279) and A. thaliana (AF076484) cDNAs clone known as GMPase, respectively. We detected the expression of GMPase using RT-PCR. The highest expression of GMPase was found in stems, and the largest amount of ascorbic acid was also presented in stems. In contrast, the leaf showed minimal level of GMPase transcript and ascorbic acid content. We propose that GMPase expression patterns were similar to the changes of ascorbic acid content in the leaves treated with diverse stresses.

저온관련 유전자인 H28 유전자를 갖고 있는 Agrobacterium MP90균주를 Desiree와 Atlantie 감자 품종의 잎절편과 공동배양한 후 약 6-8주 후에 항생제가 첨가된 선발배지에서 multiple shoots를 얻을수 있었다. 선발된 형질전환체를 대상으로 PCR 방법을 이용한 NPT II 유전자와 H28를 확인한 결과 내한성유전자가 식물체의 genome에 안정적으로 삽입되었음을 확인하였고 northern blot 확인에 의하여 내한성 유전자가 발현됨을 확인하였다.

칼슘시비량(施肥量)이 가공용 대서품종(大西品種)의 내부갈색반점발생(內部褐色斑點發生)에 미치는 영향은 다음과 같다. 칼슘시비구가 무처리구(無處理區)에 비해 내부갈색반점(內部褐色斑點) 발생율(發生率)이 상당히 감소 되었으나 칼슘시비구간에는 시비량이 증가할수록 발생율이 감소하는 경향이나 유의성은 없었다 .칼슘시비에 따른 생육상을 보면 발아율(發芽率), 초장(草長), 경수(莖數)등에서는 차이가 없었으나 生草重(生草重)에서는 Ca (200kg/ha)구에서 가장 높게 나타났다. 한편 중심공동율(中心空洞率) 발생율(發生率)은 4처리 모두 16%이상 높은 발생율을 보였으나 칼슘의 영향을 거의 받지 않는것으로 나타났다. 따라서 내부갈색반점(內部褐色斑點) 발생(發生)은 괴경내에의 칼슘결핍과 관계가 있는 것으로 판단되어 대서품종 재배시 칼슘시비를 해야 발생율을 줄일 수 있을 것으로 판단되었다.