• Journal of Environmental Science International
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• v.20 no.12
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• pp.1509-1519
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• 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.

• Food Science and Preservation
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• v.14 no.6
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• pp.716-721
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• 2007

This study was conducted to obtain the basic data on the development of resources of wild edible greens, and the industrialization of the marketing of fresh wild vegetables. We have also investigated the distributing factors at five-day traditional markets (Taebaek, Hongcheon and Hoengseong) in Gangwon district, and in Jeonnam district (Naju, Damyang and Jangseong), in May and June 2007. At each market, there were 34 to 49 diverse shops selling fresh wild vegetables except at Naju, where there were 22 shops. Between 27 to 29 kinds of fresh wild vegetable were on sale at the traditional markets in Gangwon district, and 15 to 19 kinds were on sale along with many horticultural plants in Jeonnam district. Fresh wild vegetables including Aster scaber, Petasites japonicus, Pteridium aquilinum var. latussculum, Malva verticillata, leaves of Perilla frutescens, Lactuca sativa, leaves of Capsicum annuum, and Oenanthe javanica were on sale in the markets in both districts. Those selling fresh wild vegetables were typically over 51 years of age (88%), and among these over 66.4% were over 61 years old. Less than 6 kinds of fresh wild vegetable accounted for over 72.1% of the vegetables sold. Edible wild greens were mainly packed in vinyl bags (over 77%).

• Korean Journal of Environmental Agriculture
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• v.25 no.2
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• pp.180-189
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• 2006

This survey was done to investigate the pesticide residues on agricultural products on the markets in Incheon area from 2003 to 2005. A total of 10,431 samples was analyzed the residues by GC. The violation rates of the samples over maximum residue limits (MRLs) of pesticide residues established by Korean Food and Drug Administration (KFDA) in the survey of 2003, 2004 and 2005 were 1.3%, 0.9%, and 1.2%, respectively. The rate from the samples of 2005 surveyed in general wholesale markets was 3.1%, whereas that from agricultural wholesale market was 0.93%. Of the total violated samples, more than 70% of the rates were recorded from the samples of Gyeonggi-do and Incheon area in 2003 and 2004. However, the rates from Gyeonggi-do and Incheon in 2005 were remarkably reduced to 25.6% and 23.3%, respectively. Most commonly encountered agricultural commodity over MRLs was crown daisy. Positively detected pesticides were 12, 17 and 32 in the survey of 2003, 2004 and 2005, respectively. The pesticides detected yearly over MRLs during three years were chlorothalonil, chlorpyrifos, diazinon, endosulfan, procymidone. Decreasing tendency in detected and violated rates of the residues was observed in chlorpyrifos and diazinon, while increasing tendency in detected rates was recorded in chlorothalonil, endosulfan, procymidone.

• Korean Journal of Organic Agriculture
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• v.15 no.1
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• pp.109-121
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• 2007

For developing standard method for diease, pest and weed control in environmental friendly 'Ssam' vegetable cultivation, this study was carried out to investigating agriculture material use in organic agriculture and no pesticide cultivation for lettuce, kale, leafy perilla and korean cabbage. The 28.6% of investigated farmer carried out seed sterilization by seed selection with salt solution and soaking in chitosan that not validated. For raising seedling periods, the 55.6% of farmer did not use environmental-friendly agriculture material for, diease control and the 50% of farmer used one time for. pest control. Therefore, the control of disease and pest could be achieved with one or two times use of environmental-friendly agriculture material. Seed sterilization was carried out by soil solar sterilization, one time per year in 71.4% of farmer. Weed was controled by black PE film for weed germination of furrow in many farmer, by man-power weeding for weed of ridge in 85% of farmer and by machine weeding and mulching in some farmer. During cultivation period, the major pest were Aphis gossypii in lettuce, Plutella xylostella in kale, Plutella xylostella and Phyllotreta striolata (Fabricius) in korean cabbage and Pyrausta panopealis (Walke) in feat perilla. The many farmers used environ-mental-friendly agriculture material for control of pest over 10 times for spring season, and more used sold materials in market than home-made materials. In result, it needs to develop standardized method and validate cultivation methods for control of disease and pest, and seed sterilization treatment environmental-friendly 'Ssam' vegetable.

• Journal of Mushroom
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• v.16 no.1
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• pp.31-38
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• 2018

This study investigated the synergistic effect of single inoculation and co-inoculation of phosphate-solubilizing bacteria (PSB) Pantoea rodasil LH-1and Burkholderia stabilis HS-7. Phosphate-solubilizing abilities of these strains were assessed by measuring phosphorus content in culture media that were singly inoculated or co-inoculated with these strains for 7 days. The co-inoculation of P. rodasil LH-1and B. stabilis HS-7 was found to release the highest content of soluble phosphorus ($783.41{\mu}g\;mL^{-1}$) into the medium, followed by single inoculation of B. stabilis HS-7B ($743.90{\mu}g\;mL^{-1}$) and P. rodasil LH-1 ($736.59{\mu}g\;mL^{-1}$). The highest pH reduction, organic acid production, and glucose consumption were also observed in the medium inoculated with both the strains, compared with that in the medium inoculated with the strain alone. Results of a plant growth promotion bioassay showed 7.7% and 15.5% higher leaf and root growth, respectively, in romaine lettuce co-inoculated with P. rodasil LH-1and B. stabilis HS-7 than those inoculated with the strain alone. However, no significant difference was observed between single inoculation and co-inoculation of these strains with respect to phosphorus release and plant growth. Although the results of the present study did remarkdly not show the synergistic effect of phosphate solubilization by co-inoculation of the PSB strains examined, these results indicate that treatment with PSB exerts a beneficial effect on crop growth.

• Journal of Food Hygiene and Safety
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• v.29 no.1
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• pp.1-5
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• 2014

Many community gardens in large cities worldwide grow vegetables; however, no information regarding the levels of sanitary indicator bacteria and prevalence of foodborne pathogens in vegetables grown in urban community gardens is available. To evaluate the microbiological quality of vegetables from urban community gardens in Korea, 530 samples (nine types of vegetable, including Chinese cabbage, lettuce, radish leaves, spinach, mustard leaves, crown daisy, leek, Korean cabbage, and chicory) were collected at 11 urban community gardens in Seoul, Korea from September through October 2012. The levels of total aerobic bacteria, Escherichia coli, total coliforms, Salmonella spp. Listeria monocytogenes, and E. coli O157:H7 were evaluated quantitatively and/or qualitatively. The mean numbers of total aerobic bacteria and coliforms were 6.3 log CFU/g (range 3.8-8.1 log CFU/g) and 4.3 log CFU/g (range 2.1-6.4 log CFU/g), respectively. Total coliforms were detected on 67% of whole vegetables. Chicory showed the highest number of total aerobic bacteria and coliforms, whereas the lowest number of coliforms was detected on leeks. E. coli was detected on 2.3% of whole vegetables, including lettuce, radish leaves, mustard leaves, and chicory; however, foodborne pathogenic bacteria were not detected on any of the vegetable samples using this highly sensitive and validated procedure. Based on these findings, the presence of coliforms and E. coli demonstrates that opportunity for improvement of microbiological safety exists throughout the produce production chain, although no major foodborne pathogens were present in vegetables grown in urban community gardens.

• Research in Plant Disease
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• v.19 no.4
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• pp.294-299
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• 2013

To select resistant vegetables against two species of root-knot nematodes, M. incognita and M. arenaria, 39 vegetables belongs to 7 families, 13 genera, 25 species were screened in greenhouse pot test. Susceptible vegetables to both nematodes were amarath and leaf beet in Amaranthaceae, Malabar spinach in Basellaceae, Moroheiya in Tiliaceae, and Water-convolvulus in Convolvulaceae, Pak-choi in Brassica campestris var. chinensis, Tah tasai in B. campestris var. narinosa, B. campestris var. chinensis x narinosa, Leaf mustard, Mustard green in B. juncea, Kyona in B. juncea var. laciniate, Choy sum in B. rapa subsp. arachinenesis, Kairan in B. oleracea var. alboglabra, Arugula in Eruca sativa, Garland chrysanthemum in Chrysanthemum coronarium, Endive in Cichorium endivia, Artichoke in Cynara cardunculus var. scolymus, Lettuce in Lactuca sativa. Resistant to M. arenaria but susceptible to M. incognita were B. oleracea cv. Matjjang kale, B. oleracea var. gongyloides cv. Jeok kohlrabi, and C. intybus cv. Radicchio. Resistant vegetables to both nematodes were C. intybus cv. Sugar loaf, Grumoro, Radichio treviso, B. oleracea cv. Manchu collard, Super matjjang, B. oleracea italica, B. oleracea var. botrytis italiana, and Perilla in Lamiaceae. Vegetables resistant to both species of root-knot nematodes could be used as high-valued rotation crops in greenhouses where root-knot nematodes are problem.

• Journal of Life Science
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• v.24 no.12
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• pp.1308-1315
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• 2014

Biological control using the plant growth-promoting Rhizobacterium (PGPR) has received significant attention in recent years. PGPR has been linked with promoting growth in economically important crops, such as potatoes, tomatoes, and rice. Bacillus mojavensis KJS-3 (Moja-3), isolated from food waste, possesses antifungal properties against Aspergillus terreus, A. fumagatus, A. flavus, and Fusarium redolense, and it may have potential in the development of products for industrial applications. The main purpose of this study was to determine the effects of spraying the PGPR Bacillus mojavensis KJS-3 on the growth of altari radish (leaf number, leaf length, leaf weight, root length, and rhizome length, adjacent portion diameter, and weight) and lettuce (leaf number, length, width, and weight). Three different concentrations of the foliar spray treatment of B. mojavensis KJS-3 were applied to the altari radish and lettuce: the recommended standard concentration of $1{\times}10^9cfu/g$, half the standard concentration of $0.5{\times}10^9cfu/g$, and double the standard concentration of $2{\times}10^9cfu/g$). The B. mojavensis strain foliar spray treatment increased the growth of the leaves and roots of the altari radish and increased the growth of the lettuce leaves. For both plants, the recommended concentration of B. mojavensis KJS-3 produced better growth than half the standard concentration, and the growth was similar with the double dose. This study demonstrates positive effects of Moja-3, suggesting it may be a potential new bio-fertilizer for improving the growth of altari radish and lettuce.

• Journal of Bio-Environment Control
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• v.1 no.2
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• pp.123-134
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• 1992

In order to verify the usability of the greenhouse for aquaculture with nutrient culture synchronously and to obtain the fundamental data fir the establishment of efficient farming technology, the characteristics of microclimate and the growth of leafy vegetables were examined. Tilapia averaged 428.6 g grew to 784 g(1.83 times) for 147 days from May 29 to Oct. 21 and fingerlings averaged 12.9 g grew by 1.37 times for 61 days from Sep. 13 to Nov. 12. The growth of vegetables such as water dropwort, leaf lettuce, Chinese cabbage, and Welsh onion in the greenhouse was better for aquaculture with nutrient culture than for nutrient culture only. Between above two greenhouses, pH and EC of nutrient solution was same but the temperature different by about 2$^{\circ}C$. Average day temperature, relative humidity, and $CO_2$ concentration were higher by 2.9$^{\circ}C$, 6%, and 200 ppm in the greenhouse for aquaculture with nutrient culture, respectively. Net assimilation rate of vegetables in the greenhouse was a little higher for aquaculture with nutrient culture than for nutrient culture only. Therefore, provided aquaculture and nutrient culture are carried out in the same greenhouse, the saving effect of heating cost as well as the additional promotive effects of vegetable and tilapia growth can be obtained.

• Journal of Life Science
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• v.21 no.3
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• pp.368-374
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• 2011

The relationship between MDHA reductase activity and ascorbate, dehydroascorbate, and hydrogen peroxide content was evaluated, and this experiment was conducted to determine the change of MDHA reductase activity and the level of steady-state mRNA abundance of MDHA reductase in lettuce leaves subjected to low temperature stress. MDHA reductase activity of chloroplastic and cytosolic fraction in lettuce leaves subjected to $4^{\circ}C$ for 24 hr increased, followed by a steady decrease during the duration of recovery to $20^{\circ}C$ for 48 hr. The content of ascorbate slowly increased during low temperature treatment, followed by a rapid increase during the duration of recovery to $20^{\circ}C$ for 48 hr, while dehydroascorbate content rapidly decreased. The relationship between MDHA reductase activity of chloroplastic and cytosolic fraction in lettuce leaves subjected to $4^{\circ}C$ and ascorbate content correlated positively ($R^2$=0.9240, 0.9108, respectively), but MDHA reductase activity of chloroplastic and cytosolic fraction and dehydroascorbate were reversely correlated ($R^2$=0.8638, 0.8980, respectively). Hydrogen peroxide content and MDHA reductase activity of chloroplastic and cytosolic fraction in lettuce leaves subjected to $4^{\circ}C$ correlated positively ($R^2$=0.9443, 0.9647, respectively). Northern blot analysis showed that the level of mRNA transcript of MDHA reductase was similar to total activity of MDHA reductase, and also that the level of mRNA of MDHA reductase after recovery to $20^{\circ}C$ for 24 hr decreased.