• Research in Plant Disease
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• v.9 no.1
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• pp.10-17
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• 2003

The year of 2002 was very unusual in climatic condition. Warm winter weather, high temperature and drought in March and April, little precipitation in June and early and mid-July and, nearly continuous rain-falls from late July to whole period of August accompanied with low temperature and insufficient sunshine in 2002 resulted in unfavorable conditions for plant growth in one way or another, In relation to the unusual weather, in general, diseases associated with low temperature, poor radiation and much rainfall occurred severely in this year, In rice, incidence of bacterial grain rot, and false smut increased sharply, whereas other major diseases including blast occurred mildly due mainly to the reduced application of nitrogen fertilizer, In vegetables, potato and sweet potato, and fruit trees, incidence of diseases was largely dependent on climatic condition of growth period in particular crops. However, diseases favored low temperature and much rainfall, such as Phytophthora disease increased markedly compared to those of normal years, while anthracnose and soft rot tended to decrease significantly.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.292-292
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• 2009

본 연구는 유기종자 안전 생산기술 개발을 위한 효과적인 병해충 제어를 위해 대표적인 찰옥수수 품종인 미백2호와 흑미찰을 대상으로 병?해충 발생양상을 조사하였다. 2008년 유기농 찰옥수수 종자 생산지의 우점 비산포자의 종류 중Alternaria sp., Cladosporium sp., 및 Helminthosoprium sp.,은전 생육기간에 관찰되었다. 또한종자로부터 신초 출현 전후로 종자가 발아하지 않고 부패하거나 유묘의 시들음 증상, 심하면 고사하는 증상과 거세미나방에 의해 지재부가 절단된 전형적인 피해를 관찰할 수 있었고 발병주율은 14~6% 미만이었다. 특히, 포장내 조명나방 발생밀도는 2008년 트랩당 3.5~0.5 마리로 높게 나타났으며, 2009년 트랩당 0.5~6마리로 낮게 나타났다. 또한 피해주율은 2008년은 7.5(미백2호)~21(미흑찰)%였으며, 2009년은 1~46%로 매년 높은 피해주율을 보였으며 수확기까지 지속적으로 증가하였다. 옥수수잎마름병 (Leaf blight)의 발생 양상은 2008년도에 7%(미흑찰)~34%(미백2호)로 높게 나타났으며, 2009년은 6월18일 이후 초발생하여 발병주율이 8월 21일 (59%, 미흑찰)이후 급격히 증가하여 9월 25일이는 미흑찰 (69%)의 발병주율이 미백2호 (56%)보다 높게 나타났다. 옥수수깜부기병(Common Smut)의 발생 양상은 2008년도에 20주 중 2%~15%의 발병주율을 보였으며, 2009년은 초발생 시기가 7월17일로 2008년에 비해 17일 정도 늦추어졌으며 발병주율도 8% 미만 (9월 25일)으로 2008년에 비해 아주 낮게 나타났다. 옥수수깨씨무늬병 (Southern Leaf Spot)의 발생 양상은 2008년 20주 중 초기에 평균 11%(미흑찰)에서 증가하여 9월 19일 조사시에는 두 품종 모두 62%로 높게 나타났다. 2009년은 6월8일 이후 초발생하였으며 9월 25일까지 지속적 발병하여 약 86%의 발병 주율을 보였고 2008년에 비해 24% 이상 발병주율이 높았다.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.629-647
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• 2018

This study was carried out to investigate the economic value of organic rice production using gelatin chitin microorganisms in eco-friendly complex, Gongsan, Naju city. The soil condition of experiment paddy field was Jeonbuk series and silt loam with a slightly poor drainage. Except for the high effective silicate, the chemical characteristics of soils used were included in the optimum range of paddy soils in Korea. In growth, plant length, tiller number, ear number, and ear length were observed to be higher in conventional paddy fields than organic paddy fields. However, number of grain per panicle and grain filling ratio (%) were higher in organic paddy fields than conventional paddy fields. Incidences of diseases and insect pests were slightly higher in the organic paddy fields. Water weevil, sheath blight, rice leaf roller and rice blast were more occurred in organic paddy field. On the other hand, false smut was higher occurred in conventional paddy field. There was a significant negative correlation between rice sheath blight and rice leaf roller, and rice yield. In the milled rice quality, the quality of organically cultivated milled rices was lower by the increase of broken rice than that of conventionally cultivated milled rices. The quality and palatability of rice were higher in organic cultivation with decreasing of protein content. Net income of conventionally and organically cultivated rice was 360,000 won/10a and 610,000 won/10a, respectively. Premium net income of the organically cultivated rice was 68%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.3
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• pp.233-238
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• 2006

This study was conducted to evaluate growth characteristics, yield and feed value of newly bred domestic silage corn hybrids compared to foreign imported corn hybrid. Days to silking were $78{\sim}86$ days and longer than that of P3394 (Control). Kwangpyeongok, Cheonganok, and Cheongsaok were resistant to lodging. Such trait of stay-green of Kwanganok, Kwangpyeongok, Cheonganok, Cheongsaok, and Suwon159 was not different from that of P3394. Duruok, Kwangpyeongok, and Suwon159 were more resistant to Bipolaris maydis (southern corn leaf blight) than P3394. All of the silage corn hybrids were resistant to Exserohilum turcicum (northern corn leaf blight) and Smut. Ear ratios to total dry matter (%) of Cheonganok was similar to P3394. Ear lengths of domestic hybrids were similar or longer than that of P3394. Dry matter yield of domestic hybrids except Suwon19 and Jangdaok were similar to that of P3394. Total digestible nutrient (TDN) yields, Duruok, Kwangpyeongok, Cheonganok, and Cheongsaok were similar to P3394, but Kwanganok, Suwon19, Jangdaok and Suwon159 were lower than P3394. Acid detergent fiber(ADF), Suwon19 was lowest among all hybrids, and all hybrids except Suwon19 had values ranging from 44.7 to 49.0%, similarly with P3394. Neutral detergent fiber (NDF) values of the hybrids were similar to that of P3394, and ranged from 68.1 to 72.8%, except for Duruok which was lowest. Relative feed values (RFV) of Duruok, Kwangpyeongok, Cheonganok, Jangdaok, and Suwon159 had values ranging from 71.0 to 75.7 and were not significantly different from P3394. ADF was significantly negatively correlated with number of days to silking, number of days to maturity, and fresh matter yield, but was significantly positively correlated with resistance to corn borer. RFV showed a significantly positive correlations with no. of days to maturity and fresh matter yield, but significantly negative correlation with resistance to European corn borer. Therefore, indices for evaluation of feed value as well as production were important to select corn hybrids for silage. It is concluded that domestic hybrids tested in this study have high feed value as well as high production similar to those of imported corn hybrid.

• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.93-104
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• 2010

This study was conducted screening of the population densities of fungal pathogens and insect and observed the disease symptoms on the organic sweet corn seed producing field from 2008 to 2009. The dissemination spores, Alternaria sp., Cladosporium sp., Helminthosporium sp., Pyricularia sp., Collectotrichum sp., and Bipolaris sp., were detected and the three fungal spores from the front were observed for whole growth stage. Seed and seedling diseases were shown as the rotted seed and damping-off seedling caused by Penicillium sp. and Rhizoctonia sp.. The larva of Black cutworm cut down the root crown of seedlings. The damaged plants were ranged from 14% to 16%. On the Oriental corn borer, the population densities and the percentage of damaged plants were showed a low difference between two sweet corn varieties. The population densities of Oriental corn borer were scored as from 3.5 to 20.5 in 2008 and from 0.5 to 6 in 2009. Also the percentage of damaged plants were significantly increased until harvesting stage and was recorded from 7.5% to 21% in 2008 and from 1% to 46% in 2009. On the Corn leaf blight, the percentage of diseased plant were scored from 7% to 34% in 2008. The first occurrence of date was after June 18, and the percentage of diseased plant was continuously increased after August 21 and the values of diseased plants was ranged from 56% to 69% in 2009. On common smut, the percentage of diseased plant was recorded from 5% to 15% in 2008, and the first occurrence date were delayed as 17 days (July 17) and were showed less than 8% of diseased plants in 2009. Corn Southern Leaf spot was scored as average 11% at early stage and showed high score as 62% at September 19 in 2008. In 2009, the first occurrence date were advanced about 20 days (after June 8), and continuously increased up to 86% in 2009.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.4
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• pp.287-296
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• 2007

The experimental work was conducted to determine the growth characteristics and yield of whole crop rice (cv. Suwon 468 and cv. Chuchungbeo) and soil properties using various type of livestock manure application on rice paddy land for 3 years ($2003{\sim}3005$). Compared Suwon 468 and Chuchungbeo, Suwon 468 has longer plant height and more DM yield than that of Chuchungbeo. Among livestock manure type, plant height was longer in order of liquid swine manure (LSM) > composted swine manure (CSM) > chemical fertilizer (CF) > composted cattle manure (CCM). Number of branch on Chuchungbeo had more than that of Suwon 468. Among livestock manure type, number of branch had more in order of LSM > CSM > CF > CCM. DM yield of whole crop rice (WCR) was affected by various types of livestock manure application and increased in order CSM > CCM = LSM. DM yield on the effects of application level of LSM was highest in LSM 75% + CF 25%. Plant diseases such as rice blast, damage by insect, smut, sheath blight occurred in LSM and CSM and there was not significantly different among application level of LSM. The nitrogen content of WCR by CSM was the highest of all treatments and the ripened ratio by CSM was in contrary order. Moreover the feed value of WCR was not significantly different among treatments. Soil pH, organic matter and total nitrogen was not different by LSM application whereas phosphorus content increased by LSM application. Cu and Zn content increased by LSM and CSM application and were not different by CCM as compared to control plots.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.641-651
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• 2022

The biodiversity research of barley, a functional food, is proceeding to conserve germplasms and develop new cultivar of barley to improve its functional effects. In this study, with 25,104 barley germplasms in the National Agrobiodiversity Center, South Korea, the biodiversity index of species was much lower (1.17) than the origins (24.73) because of the presence of a biased species, Hordeum vulgare subsp. vulgare, but the species and origin of germplasms were significantly different with regard to genetic traits. In the clustering analysis based on genetic traits, we found that 97% barley germplasms could mostly be distributed between 1~7 clusters out of a total of 15 clusters; 'normal and uzu type', 'lodging', and 'loose smut' were commonly represented in the 1~7 clusters and some clusters showed specific differences in five genetic traits including 'growth habit'. In correlation of each genetic trait, the infection of 'barley yellow mosaic virus' was highly correlated to 'number of grains per spike'. '1000 grain weight' was weakly correlated with seven genetic traits including 'number of grains per spike'. Our analysis for barley's biodiversity can provide a useful guide to the species' phenotypes that need to be collected to conserve biodiversity and to breed new barley varieties.