• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.4
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• pp.32-42
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• 2005

To investigate the plants invasion process and dominant species in large-scale cutting slopes, slopes elapsed one year to thirteen years after construction had been selected in five counties. The obtained results are summarized as follows : The species of high appearance frequency were Alnus firma, Arundinella hirta, Miscanthus sinensi var. purpurascens, Erigeron cancdensis, Artemisia princeps var. orientalis, Oenothera odorata, Lactuca raddeana, Lactrca indica var. laciniata, Lespedeza bicolor, Youngia sonchifolia, Populus albaglandulosa, and so on. The biological type of identified vascular plants was $Ch-D_1-R_{5-e}$. In time, plant coverage was increased gradually and average of plant coverage was 1.17% in slopes which elapsed one year, 42.44% after six years, 56.67% after eight years, and 69.17% after ten years. The dominant species in the surveyed slopes were covered with Alnus firma, Artemisia princeps var. orientalis, Erigeron cancdensis, Miscanthus sinensi var. purpurascens, Arundinella hirta, Lactuca raddeana, Oenothera odorata, Boehmeria spicata, Kummerowia striata and Artemisia montana of the 59 species. The conditions of location in large-scale cutting slopes are hard to fix and germinate of seeds, and extend plant roots in the slope soil. Hence, the highly appearance species and dominance species of the area will make plant coverage quick and slope stable.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.467-473
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• 2011

Flavonoid are large group of the polyphenolic compounds which are distinguished by an aromatic or phenolic ring structure and the phenolic compounds are induced by microbial infection, ultraviolet radiation, temperature and chemical stress. They are known for their antioxidant activity, anti-allergic, anti-inflammatory, anti-microbial and anti-cancer activities. In this study, changes in flavonoid content were investigated using heterologous chalcone isomerase (CHI) expression system. Also, phenolic compounds level was measured to examine the relation between flavonoids and phenols contents. Explants of lettuce (Lactuca sativa L.) were transformed with Agrobacterium tumefaciens LBA 4404 strain containing pFLH-CHI (derived from pPZP2Ha3) vector constructed with CHI gene from Brassica rapa. The putative transgenic plants were confirmed by genomic DNA PCR analysis. Also the transcription levels of the gene were analyzed by semi-quantitative RT-PCR with gene specific primers. The total flavonoid contents were increased at $T_0$ and $T_1$ generations over 1.4 and 4.0 fold, respectively. Total phenol contents also increased at $T_1$ generation. These results indicate that CHI gene plays an important role to regulate the accumulation of flavonoids and its component changes.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.09a
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• pp.55-55
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• 2005

• Korean Journal of Medicinal Crop Science
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• v.3 no.2
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• pp.151-155
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• 1995

Chromatographic separation of Laduca raddeana extract afforded a mixture of fatty acyl triterpene, triterpene acetates and primary long chain alcohol. The kind of triterpene moieties in these two triter­penoids was six, i.e., ${\beta}-amyrin,\;{\alpha}-amyrin$, lupeol, pseudotaraxasterol, taraxasterol and germanicol on the basis of chemical and spectroscopic methods. The acyl moieties in the corresponding acyl mixture were characterized as acetates, myristate, palmitate, stearate and arachidate. And a mixture of primary long chain alcohol were composed of teracosanol and hexacosanol.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.151-154
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• 2007

Phytoplasma was identified from leaf lettuce (Lactuca sativa) cultivated in commercial green-house in Korea. Diseased leaf lettuce revealed proliferation of shoots, and yellowing and shrinking of leaves (lettuce proliferation-K). Polymerase chain reaction (PCR) with universal primer pair P1/P6, and aster yellows (AY) specific primer pair R16F1/R1 amplified 1.5kb and 1.1kb length of DNA fragments, respectively. Nucleotide sequences of 16S rRNA gene were determined (Gen Bank accession no EF489024). Phylogenetic analysis of 16S rDNA showed the closest relationship with AY phytoplasma (GenBank accession no. AY389822 and AY389826), indicating that lettuce proliferation-K is a member of AY. Phytoplasma bodies were detected in phloem sieve tubes of diseased lettuce by transmission electron microscopy. The structures had round or pleomorphic shapes with a diameter of 130-300nm. Phylogenetic analysis of 16S rRNA gene, microscopic observation of phytoplasma bodies and symptomatology indicated that lettuce proliferation-K is caused by phytoplasma in the AY group. This is the first report of phytoplasma disease in lettuce in Korea.

• Plant Resources
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• v.7 no.1
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• pp.69-76
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• 2004

Lettuce (Lactuca sativa L.) is known to contain water-soluble substances that are biologically active. Aqueous or methanol extracts and residues from leaves of lettuce plants were assayed to determine their allelopathic effects, and the causative allelochemicals from fractions were quantified by means of HPLC analysis and bioassayed. Extracts from oven-dried leaf samples were more phytotoxic than those from freeze-dried samples. Leaf extracts of 40 g L$^{-1}$ were completely inhibitory on root growth of alfalfa (Medicago sativa L.), while root growths of barley (Hordeum vulgare L.) and soybean (Glycine max L.) were less sensitive. Early seedling growth of both alfalfa and barnyard grass (Echinochloa crus-galli) was significantly reduced by methanol leaf extracts. The major allelopathic substances analyzed by HPLC were coumarin, trans-cinnamic acid, o-coumaric acid, p-coumaric acid and chlorogenic acid. Of them p-coumaric acid was found as the greatest amount (8.9 mg 100 g$^{-1}$ ) in the EtOAc fraction; only coumarin was found in all the fractions. Hexane and EtOAc fractions of L. sativa reduced alfalfa root growth more than did BuOH and water fractions. These results suggest that lettuce had potent herbicidal activity, and that its activity differed depending on type and amount of causative compounds by fraction.

• Journal of Environmental Science International
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• v.33 no.1
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• pp.59-65
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• 2024

The objective of this study were to assess rooftop urban agriculture and analyze the differences in soil, growth, physiology, and productivity to elucidate the effect of companion planting with various plants, including lettuce (Lactuca sativa), rosemary (Salvia rosmarinus), marigold (Tagetes patula), Korean perilla (Perilla frutescens), and garlic chives (Allium senescens). Measurements were taken every other week from May to August 2023, totaling eight measurement. Regarding the characteristics of the soil planted with lettuce and aromatic plants, the combined planting of lettuce and garlic chives created a favorable soil environment for plant growth. Consequently, the best growth was observed when lettuce and garlic chives were companion planted. Companion planting of lettuce and garlic chives appears to be the most efficient concerning growth and physiology. The productivity of companion planting lettuce and aromatic plants also showed high-quality lettuce when lettuces and garlic chives were companion planted. Therefore, companion planting of lettuces and garlic chives in rooftop urban agriculture is suitable for growth, physiology, and productivity.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.18-25
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• 2001

Ethanol extracts from 46 vegetables were tested their insecticidal activities toward five agricultural insect pests and four stored-product insect pests. The efficacy varied with both agricultural insects/stored-product insects and vegetable species used. Potent insecticidal activities, at the concentration of 5,000 ppm, were produced from extracts of Nelumbo nucifera and Ulva lactuca against Myzus persicae, Zea ways and Z. mays (leaf) against Nilaparvata lugens, Citrullus vulgaris (seed) and U. lactuca against Plutella xylostella, N. nucifera, Z. mays, and Z. mays (leaf) against Spodoptera litura, and C. vulgaris (seed), Daucus carota, Helianthus annuus (leaf), H. annuus (flower), Lactuca sativa, and Zingiber officinale against Tetranychus urticae. Potent insecticidal activities at the concentration of 2,500 ppm were exhibited from the extracts of N. nucifera and U. lactuca against M. persicae, Z. mays against N. lugens, C. vulgaris (seed) and U. lactuca against xylostella, N. nucifera and Z. mays against S. litura, and C. vulgaris (seed), H. annuus (flower), and L. santiva against T. urticae. Against four stored-product insect pests at 50 ppm, extracts of C. vulgaris (seed) and Cucurbita moschatla (seed) against Sitophilus oryzae and C. vulgaris (seed), H. annuus (seed), and Z. officinale against Plodia interpunctellfa revealed potent insecticidal activities over 80% mortality. In tests with Callosobruchus chininsis and Lasioderma serricorne, extracts of all vegetables tested exhibited meager and no activity.

• Journal of Life Science
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• v.19 no.2
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• pp.206-212
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• 2009

The bio-active materials were isolated from prickly lettuce (Lactuca serriola) by using several extraction solvents. The contents of general compounds, vitamins, polyphenols and flavonoids of prickly lettuce were analysed. In addition, nitrite scavenging activity, anti-oxidative activity and anti-microbial activity of methanol extracts were measured. The ethylacetate (EtOAc) fraction of methanol extracts of prickly lettuce showed the best on the nitrite scavenging activity, anti-oxidant activity and anti-microbial activity. And also, the contents of polyphenols and flavonoids were the highest among all fractions. The subfraction 2 (EtOAc:MeOH=3:1) of EtOAc fraction showed the strongest anti-oxidative activity among 5 subfractions. The subfraction 2 was identified as ${\rho}$-coumaric acid and caffeic acid by GC-MS. The anti-microbial activity of each solvent fraction from prickly lettuce was measured. The EtOAc fraction showed the strongest anti-microbial activity. Overall, these results may provide the basic data to understand the biological activities of bio-active materials derived from prickly lettuce.

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.270-276
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• 1997

This experiment was conducted to develop a practical method to growth in hydroponics conditions. For this purpose, leaf lettuce (Lactuca sativa L., cv. 'Cheongchima') was cultivated under different temperature and light conditions in experimental fields of Sahmyook university from March, 1991 to May, 1996. The visual quality score(VQS), a quantitative parameter to evaluate harvested leaf lettuce quality. The leaf lettuce cultivated at $25^{\circ}C$ solution temperature showed the highest fresh weight pe, plant (59.7g/plant), but lowest visual quality score (5.2), while leaf lettuce cultivated at 15$^{\circ}C$ solution temperature showed lower fresh weight per plant (25.2g/plant) but highest visual quality score (7.2). In general, growth of leaf lettuce was retarded by low solution temperature, but quality was higher than those of other solution temperature. Different day/night temperature of nutrient solutions 20/2$0^{\circ}C$ and 25/2$0^{\circ}C$ was highest in yield, but leaf type was grow longer, and visual quality are inferior to low temperature. Yield was decreased as 10 and 25% at 60 and 80% shading treatment, respectively. Chlorophyll content was decreased by shading. but plant height and root length were increased of leaf lettuce growth with hydroponics.