• The Korean Journal of Ecology
• /
• 제20권4호
• /
• pp.233-238
• /
• 1997

To evaluate allelopathic effect of volatile chemicals and phytohormones, seed germination and seedling growth test of Lactuca sativa have performed in laboratory experiments. Among used chemicals terpienen-4-ol was the most inhibitory to seed germination of lettuce. ABA and GA inhibited seed germination at $5{\times}10^{-6}M$ concentration but promoted germination at $2.5{\times}10^{-5}M$ and $5{\times}10^{-5}M$. ABA and GA alleviated volatile chemical-induced inhibition of seed germination and seedling elongation of lettuce.

• The Korean Journal of Ecology
• /
• 제21권2호
• /
• pp.151-156
• /
• 1998

the phytotoxic effects of volatile substances emitted from the tomato plant (Lycopersicon esculentum) on receptor plants such as Bidens bipinnata, Plantago asiatica, Lactuca sativa, Eragrositis ferruginea and Achyranthes japonica were investigated. Bolatile substances from the leaves inhibited seedling growth of receptor plants in the laboratory tests. The inhibition response varied with the concentration of compounds. To identify the phytotoxic compounds from tomato plant a GC/MS method was employed. Forth compounds, such as trans-2-hexeal, linalool, phenylacetaldehyde, methlsalicylic acid and tetradecanaic acid were identified from the essential oil of tomato plants. The findings suggest that the tomato plant may have allelopathic potential.

• Mycobiology
• /
• 제33권4호
• /
• pp.243-244
• /
• 2005

Three fungi newly intercepted from importing plants were identified in 2004. They were Ascochyta chrysanthemi on Lactuca sativa from China, A. spinaciicola on Spinacia oleracea from Denmark, and Leptosphaerulina australis on Brassica oleracea var. capitata from China. The characters of these fungi were described and illustrated.

• 한국식물생명공학회:학술대회논문집
• /
• 한국식물생명공학회 2004년도 생명공학 실용화를 위한 비젼
• /
• pp.102-102
• /
• 2004

• 한국식물생명공학회:학술대회논문집
• /
• 한국식물생명공학회 2004년도 춘계학술대회
• /
• pp.58-58
• /
• 2004

• 한국식물생명공학회:학술대회논문집
• /
• 한국식물생명공학회 2006년도 한국육종학회 공동심포지엄 및 학술대회
• /
• pp.32.1-32.1
• /
• 2006

• 한국환경과학회지
• /
• 제20권12호
• /
• pp.1509-1519
• /
• 2011

The protective effect of nitric oxide (NO) on the antioxidant system under paraquat(PQ) stress was investigated in leaves of 8-week-old lettuce (Lactuca sativa L.) plants. PQ stress caused a decrease of leaf growth including leaf length, width and weight. Application of NO donor, sodium nitroprusside (SNP), significantly alleviated PQ stress induced growth suppression. SNP permitted the survival of more green leaf tissue preventing chlorophyll content reduction and of higher quantum yield for photosystem II than in non-treated controls under PQ exposure, suggesting that NO has protective effect on chloroplast membrane in lettuce leaves. Flavonoids and anthocyanin were significantly accumulated in the leaves upon PQ exposure. However, the rapid increase of these compounds was alleviated in the SNP treated leaves. PQ treatment resulted in lipid peroxidation and induced accumulation of hydrogen peroxide ($H_2O_2$) in the leaves, while SNP prevented PQ induced increase in malondialdehyde (MDA) and $H_2O_2$. These results demonstrate that SNP serves as an antioxidant agent able to scavenge $H_2O_2$ to protect plant cells from oxidative damage. The activities of two antioxidant enzymes that scavenge reactive oxygen species, superoxide dismutase (SOD) and catalase (CAT) in lettuce leaves in the presence of NO donor under PQ stress were higher than those under PQ stress alone. Application of 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), a specific NO scavenger, to the lettuce leaves arrested SNP mediated protective effect on leaf growth, photosynthetic pigment and antioxidant systems. However, PTIO had little effect on lettuce leaves under PQ stress compared with that of PQ stress alone. The obtained data suggest that the damage caused by PQ stress is in part due to increased generation of active oxygen by maintaining increased antioxidant enzyme activities and SNP protects plants from oxidative stress. From these results it is suggested that NO might act as a signal in activating active oxygen scavenging system that protects plants from oxidative damage induced by PQ stress and thus confer PQ tolerance.

• 생물환경조절학회지
• /
• 제16권4호
• /
• pp.348-351
• /
• 2007

본 실험은 양액조성 및 단비 처리에 의한 엽채류의 질산염과 비타민 C와 같은 내적품질 변화를 알아보고자 하였다. 2주일간 정상적인 배양액에서 재배한 후 다시 2주일간 서로 다른조건의 양액에서 재배한 청경채, 청치마상추, 로메인상추는 단비처리구를 제외하고는 생육에 큰 차이를 보이지 않았다. 내적 품질로 질산염은 야마자키 상추 1배 양액 처리구에서 가장 높았으며 다음으로 $+NH_4$ 처리구 순서였고 $-NO_3$와 단비 처리구에서 가장 낮았다. 비타민 C 함량은 대체로 질산염과 반대의 결과를 나타내어 청치마, 로메인상추에서는 단비처리구에서 청경채는 $-NO_3$처리구에서 가장 높았다. 이들 질산염과 비타민 C 함량간의 상관계수는 청경채는 -0.614, 로메인상추는 -0.651이었으며 특히 청치마상추는 -0.804를 나타내었다.

• 식물병연구
• /
• 제12권3호
• /
• pp.294-297
• /
• 2006

Leafy lettuce(Lactuca sativa L.) is one of the most important vegetable crops in Korea, cultivated throughout the year in greenhouses. During the autumn of 2005, powdery mildew of lettuce that is a new disease caused by Podosphaera fusca occurred in several plantings grown in plastic houses near Suwon in central Korea. Further survey on commercial fields of the plant in central and southern Korea revealed its widespread occurrence and severe losses. Infections occur on upper part of mature leaves often cause leaf distortions, withering, and reduced vigor and growth. Among 184 greenhouses surveyed 121 were infested by the disease and 52 showed over 10% infection rate. Yields were greatly reduced by the disease reaching only 59% compared to healthy plants. About 60% leaves of infected plant were not marketable and fresh weight of the leaves was 73.6% compared to healthy leaves. Total yield of the greenhouses infested by the disease ranged from $100{\sim}140kg$, while it was 260 kg in a non-infested greenhouse at one time harvest. Since the disease represents a threat to safe cultivation of leafy lettuce in Korea, environmentally-friend control strategies should be urgently developed.

• 식물조직배양학회지
• /
• 제27권6호
• /
• pp.435-439
• /
• 2000

겨울 상추 품종인 청치마 상추의 자엽조직을 ${\gamma}$-TMT유전자가 도입된 A. tumefaciens LBA 4404와 공동배양한 후, 50 mg/L kanamycin, 500 mg/L carbenicillin, 0.1 mg/L NAA, 0.5mg/L BA가 첨가된 MS재분화 배지에 옮겨 약4주 배양하여 재분화된 신초를 얻었다. 재분화된 신초를 50 mg/L kanamycin, 250mg/L carbenicillin이 포함된 MS 기본 배지에 옮겨 발근된 소식물체를 얻었다. 선발된 형질전환 식물체의 genomic DNA에 대한 PCR분석과 Southern분석을 수행하여 애기장대 ${\gamma}$-TMT유전자 특이적 DNA단편이 상추의 genomic DNA내에 삽입되었음을 확인하였다. 선발된 상추 형질전환체 잎의 $\alpha$-tocopherol/${\gamma}$-tocopherol 함량 비율이 대조 식물체에 비하여 약 4배 증가하여 도입된 ${\gamma}$-TMT유전자가 안정적으로 발현함을 나타내었다.