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The purpose of this study was to evaluate microbial contamination of melons in Korea. A total of 123 samples including melon fruits, leaves, seeds, soils, and irrigation water were collected from farms and markets to detect total aerobic bacteria, coliform, Escherichia coli, and pathogenic bacteria such as Bacillus cereus, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus. Samples were collected from Iksan and Nonsan farms to monitor bacterial levels on pre-market melons. The total aerobic and coliform bacteria on melon cultivation were between 0.43 and 6.65 log CFU g -1 , and 0.67 and 2.91 log CFU g -1 , respectively. Bacillus cereus, a fecal coliform, was detected in soils and melon leaves from Iksan farm at 2.95, 0.73 log CFU g -1 , respectively, and in soils from Nonsan farm at 3.16 log CFU g -1 . Market melon samples were collected to assay bacterial load on melon being sold to consumers. The contamination levels of total aerobic bacteria in agricultural markets, big-box retailers, and traditional markets were 4.82, 3.94, 3.99 log CFU g -1 , respectively. The numbers of coliform in melon on the markets ranged from 0.09 to 0.49 log CFU g-1. Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus were not detected in any samples. The count of total aerobic bacteria on melon seeds ranged from 0.33 to 3.34 log CFU g -1 . This study found that irrigation water, soil, manure and various farm work activities including post-harvest processes were latent sources of microbial contamination. These results suggest that hygienic management and monitoring of soil, water, and agricultural material should be performed to reduce microbial contamination in melon production.

Gray mold caused by Botrytis cinerea was found on a carrot seedling in a greenhouse and a field at Daegwallryeong, Gangwon Province in [2007][2008][2009]. Symptoms included irregular, brown, blight, or chlorotic halo on leaves and petioles of the carrots. Fungal conidia were globose to subglobose or ellipsoid, hyaline or pale brown, nonseptate, one celled, 7.2-18.2 × 4.5-11 µm (12.1 × 8.3 µm) in size, and were formed on botryose heads. B. cinerea colonies were hyaline on PDA, and then turned gray and later changed dark gray or brown when spores appeared. The fungal growth stopped at 35 o C, temperature range for proper growth was 15-25 o C on MEA and PDA. Carrots inoculated with 1 × 10 5 ml conidial suspension were incubated in a moist chamber at 25 ± 1 o C for pathogenicity testing. Symptoms included irregular, brown, water-soaked rot on carrot roots and irregular, pale brown or dark brown, water-soaked rot on leaves. Symptoms were similar to the original symptoms under natural conditions. The pathogen was reisolated from diseased leaves, sliced roots, and whole roots after inoculation. As a result, this is the first report of carrot gray mold caused by B. cinerea in Korea.

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This study was surveyed that water physiochemical characteristics and phytoplankton incidence of main stream and Lake Doam near to Daegwallyeong agricultural area. Based on above results, it was conducted to get information overall water characteristics in south Han upstream river. COD value of Lake Doam was 6.1 mg L -1 and T-P (Total phosphorous) from there was 0.26 mg L -1 which was higher than the value of grade Ⅵ based on lake water living environment standard. Suspended solid was an average of 9.77 NTU which was higher than value of lake living standard. Concentration of phytoplankton was over 2.0×10 3 Cell mL -1 from July to September. It was considered that cyanobacteria were occurred due to massive influx of nutrient material by high temperature and rainfall during this season. Compare to Ontario's sediment quality guidelines, T-N and T-P was middle value between LEL and SEL in Lake Doam. This value means that contamination in water is serious. Therefore, it is considered that systematic management was needed to reduce and block contamination source.