• Title/Summary/Keyword: 노균병

Search Result 52, Processing Time 0.018 seconds

Occurrence and Control of Downy Mildew of Netted Melon in Chonnam Province (전남지역 온실멜론의 노균병 발생 및 방제 실태)

  • 고영진;안미연;서정규
    • Korean Journal Plant Pathology
    • /
    • v.12 no.4
    • /
    • pp.459-462
    • /
    • 1996
  • 예년과는 달리 6월 중순부터 7월 중순까지 낮은 기온과 잦은 강우로 인한 음습한 날씨가 지속되었던 전남지방의 온실멜론에서 노균병이 격발하였다. 올해 전남지역에서 심하게 발생한 노균병의 병징은 다각형의 모무늬 외에도 불규칙한 대형의 부정형 무늬를 형성하였으며, 이러한 급성형 병징들은 주로 개화기 무렵 아랫잎에서부터 나타나기 시작하여 병이 진전됨에 따라 윗쪽으로 진전되었고 병반이 뭉쳐져 잎을 급속하게 고사시켰다. 표본 조사한 12개 농가의 시설 하우스에서 재배되고 있는 온실멜론의 노균병 이병엽율은 1%에서 100%까지 다양하였으며 수확을 전혀 못한 농가도 있었다. 각 농가에서는 노균병의 방제를 위하여 발병초기부터 농가당 최소 3회에서 최고 8회까지 살균제를 살포하는 방제 노력을 기울였으나 정확한 노균병 진단의 실패와 적정 약제 선정의 실패로 혼선을 빚어 방제효과는 높지 않았으며, 농약의 남용과 오용이 병방제에서 심각한 문제점으로 드러났다.

  • PDF

Identification of novel genes for improvement of downy mildew resistance in Zea mays (옥수수의 노균병 저항성 증대를 위한 저항성 유용유전자 발굴)

  • Min, Kyeong Do;Kim, Hyo Chul;Kim, Kyung-Hee;Moon, Jun-Cheol;Lee, Byung-Moo;Kim, Jae Yoon
    • Korean Journal of Environmental Biology
    • /
    • v.37 no.4
    • /
    • pp.493-502
    • /
    • 2019
  • Maize (Zea mays L.) is a C4-plant and one of the three major crops grown worldwide. Because of its high productivity, maize is considered as one of the most important food and feed stocks in the world. Recently, bioethanol from maize was predominantly generated in the USA and Brazil. Infection of maize by several diseases resulted in a huge disaster and prevented maize production. Downy mildew, caused by Peronosclerospora sorghi, is one of the most serious diseases of maize. Despite efforts to develop downy mildew-resistant cultivars or seed treatment with metalaxyl, downy mildew persists as a serious pathogen and is still prevalent in specific geographical locations. Analysis of soils infected with downy mildew and investigation of candidates associated with downy mildew resistance is an attractive method to overcome downy mildew damage in maize. In a previous study, we reported that maize chromosome 6 carries a possible candidate gene for downy mildew resistance. Using bioinformatics tools and RT-PCR analysis, five novel genes including bZIP, OFP transcription factor, and Ppr were identified as candidate genes associated with downy mildew resistance.

Effect of Organic Materials and the Removal of Apical Shoot on Controlling Cucumber Downy Mildew (유기농업자재와 순지르기를 이용한 오이 노균병 방제)

  • Park, Jong-Won;Kim, Yong-Ki;Park, So-Hyang;Hong, Sung-Jun;Shim, Chang-Ki;Kim, Min-Jeong;Park, Jong-Ho;Han, Eun-Jung;So, Hyun-Gyu;Kim, Seok-Cheol
    • Korean Journal of Organic Agriculture
    • /
    • v.24 no.4
    • /
    • pp.919-929
    • /
    • 2016
  • This study investigated the effect of organic materials (Bordeaux, Loess-sulfur) and the removal of apical shoot against downy mildew disease on cucumber cultivated in greenhouse. Five kinds of Bordeaux were made by adjusting mixing ratio of lime and copper sulfate in order to elucidate the optimal combination. The 4-6type Bordeaux was selected as the most effective combination for controlling cucumber downy mildew. Loess-sulfur showed inhibitory activity against cucumber downey mildew, but it was less effective than Bordeaux. It was confirmed that apical shoot cutting could reduce the incidence of cucumber downy mildew disease by 56.3%. When apical shoots of susceptible cucumber variety were cut at different leaf stages, disease incidence by early apical shoot cutting treatment was lower than that of late apical shoot cutting treatment. However in a resistant variety, 'Heukryungsamcheok', disease incidences of all cucumber apical shoot cutting treatments were lower than that of non-cutting treatment, but there was no differences between apical shoot cutting treatments due to low disease incidences. In addition, when organic materials and apical shoot cutting treatment were carried out in parallel, the combined treatments of organic materials and apical shoot cutting showed low disease incidence of cucumber downy mildew compared to untreated control. The lowest disease incidence of cucumber downy mildew was recorded in the combined treatment of 4-6type Bordeaux and apical shoot cutting. This study confirmed that apical shoot cutting can reduce the disease incidence of cucumber downy mildew and the combined treatment of apical shoot cutting and organic materials showed higher suppressive effect against cucumber downy mildew.

Control of Spinach Downy Mildew by Forced Ventilation in Greenhouse Cultivation (강제환기처리에 의한 비닐하우스재배 시금치의 노균병 발생 억제)

  • Park, Seok-Hee;Lee, Joong-Hwan;Woo, Jin-Ha;Choi, Seong-Yong;Park, So-Deuk;Moon, Yong-Sun
    • Korean Journal of Organic Agriculture
    • /
    • v.22 no.1
    • /
    • pp.147-154
    • /
    • 2014
  • Spinach downy mildew caused by Peronospora spinaciae is the main reason of yield reduction in Korea as well as in worldwide. After forced ventilation or horizontal air circulation fans were installed to control growth conditions in green house, the changes of temperature, relative humidity (RH), growth and yield, and occurrence of downy mildew were examined. Althought here was no significant difference of temperature between the treatments, RH as 9.2% lower at nighttime by forced ventilation. In addition, final fresh weight was increased to 17.8g compared to control (10.1g), which as 7.7g enhancement. Downy mildew s tarted to show 20 days after sowing (DAS) and increased to 34.7% at 60 DAS on harvest time in control. In contrast downy mildew was occurred 40 DAS with 0.7% incidence rate and 4% at harvest by forced ventilation. The results indicated that reduction of only 9.2% of RH at nighttime by forced ventilation in greenhouse spinach growth was dramatically thrived over 76.2%. Additionally spinach downy mildew occurred 20 days later with extremely lower incident rate, which meant 88.5% reduction of downy mildew.

Control of downey mildew occurred on cucumber cultivated under plastic film house condition by optimal application of chemical and installation of ventilation fan (환기조절 및 약제적기살포에 의한 비닐하우스재배 오이에 발생하는 노균병 방제)

  • Kim, Yong-Ki;Ryu, Jae-Dang;Ryu, Jae-Gee;Lee, Sang-Yeob;Shim, Hong-Sik
    • The Korean Journal of Pesticide Science
    • /
    • v.7 no.3
    • /
    • pp.223-227
    • /
    • 2003
  • Survey on plant diseases occurring on cucumber cultivated in plastic film house of experimental farm in Suwon was conducted. Through the survey, occurrence of damping-off, downey mildew, powdery mildew and Fusarium wilt was observed. Especially downey mildew caused by Pseudoperonospora cubensis was the most severe foliar disease of cucumber. To control the disease effectively, effects of installation of ventilation fan and optimal spray timing of a chemical, dimethomorph+copper oxychloride WP, were investigated. Two ventilation fans installed at the front and at the back of plastic film house reduced air relative humidity by about 6.4% and downey mildew incidence by 55.7%. Downey mildew incidence on cucumber from untreated chemicals plot in plastic film house installed with ventilation fan was on a equal level with that from treated chemicals plot with three times application of dimethomorph+copper oxychloride WP in plastic film house without ventilation fan. Meanwhile in order to select optimal chemical application time, dimethomorth+copper oxychloride WP was treated three times at 7 days-interval from three days before the disease occurred, right after the disease occurred, and two days after the disease occurred, respectively. The result showed that dimethomorth+copper oxychloride WP applied to cucumber leaves and stems from three days prior to, right after, two days after occurrence of downey mildew reduced downey mildew incidence by 72.9, 61.8, and 23.7%, respectively. The above results showed that regulation of environmental factors like air relative humidity and preventive application of chemicals should be considered to establish control strategy to downey mildew.