• 제목/요약/키워드: late leaf spot

검색결과 34건 처리시간 0.022초

Gray Leaf Spot in Peppers Caused by Stemphylium solani and S. lycopersici

  • Kim, Byung-Soo;Yu, Seung-Hun;Cho, Hyun-Jung;Hwang, Hee-Suk
    • The Plant Pathology Journal
    • /
    • 제20권2호
    • /
    • pp.85-91
    • /
    • 2004
  • A disease causing severe leaf spots in pepper plants has been observed in northern Gyeongbuk and Gangwon provinces in Korea since 1994. The current study diagnosed the disease as gray leaf spot caused by Stemphylium solani Weber and S. lycopersici (Enjoji) Yamamoto, both of which are pathogenic in pepper and tomato plants. Although the disease has been found in almost all areas where peppers are grown, it is more severe in mountain terrains where the nights are cool. Both species of pathogenic fungi were found to sporu-late profusely on V-8 juice agar in plastic or Pyrex glass Petri dishes, although not in domestically-produced glass Petri dishes, when cultured at $20^{\circ}C$ under irradi-ation from a daylight fluorescent lamp with a 12-hour light and dark alternation. The domestically-produced glass Petri dishes, which are made of window glass, were found to block near ultraviolet wavelengths, around and below 300 nm, which explained why the fungi did not sporulate. However, sporulation decreased at above $25^{\circ}C$ and most isolates failed to sporulate above $27^{\circ}C$. The worst level of disease was obtained when the inoculated plants were incubated with a $15^{\circ}C$ night and $20^{\circ}C$ day temperature regime relative to 4 night/day temperature combinations (15/20, 20/25, 25/30, and 30/35$^{\circ}C$).

벼 깨씨무늬병 발생의 환경요인 분석 (Environmental Factor Analysis of Helminthosporium-Leaf-Spot-Disease Occurrence in Rice)

  • 원종건;서영진;최장수;김승한;김종수;윤재탁
    • 한국작물학회지
    • /
    • 제51권3호
    • /
    • pp.199-203
    • /
    • 2006
  • 벼 깨씨무늬병 발병 원인을 구명하기 위하여 경북지역 상습발생지 토양을 대상으로 토양특성, 식물체의 양분함량 및 이병정도에 따른 벼 수량감소 정도를 조사하고 깨씨무늬병 발생에 영향을 주는 인자를 분석한 결과는 다음과 같다. 1. 발병포장의 토양유형은 양분보유력이 낮은 사질습답 50%, 사질답이 28.3%로 전체 78.3%였고, 배수불량 토양이 67.4%를 차지하였다. 2. 병 발생이 심한 영남내륙산간 및 동해안 중, 남부지역에서 강수량이 많았고, 평균기온, 최고기온, 최저기온 및 습도와 깨씨무늬병 발병과는 관계는 부의 상관이 있었고, 강수량과는 정의 상관이 없었다. 3. 발병포장의 토양 화학성은 경북지역 논토양의 화학성에 비해 유기물, 치환성양이온, 유효규산 함량이 매우 낮은 편이며, 특히 정상지에 비해 유효규산, 아연함량이 유의하게 낮았다. 4. 이병주의 양분함량은 정상주에 비해 질소, 규산의 함량이 매우 낮았다. 5. 피해가 심한 벼는 정상 벼에 비해 간장 및 수장이 짧았고, 등숙비율은 27.9% 감소되었으며, 쌀 수량은 약 37% 정도 감수되었다. 6. 벼 깨씨무늬병 발병에 따른 미질 특성은 피해가 심할 수록 쇄미 및 심복백미의 증가로 완전미율이 11.5% 정도 더 떨어졌으며, 단백질 함량은 현저히 높아져 식미치는 피해가 높을수록 현저히 저하되었다. 7. 따라서 깨씨무늬병 발생은 양분보유력이 낮고 양분의 용탈이 심하며 유효규산 함량이 낮은 사질토양에서 주로 발생되며 생육후기 양분결핍에 의해 주로 발생되는 것으로 사료되었다.

Effect of Plant Population Densities on the Severity of tate Leaf Spot and Rust of Groundnut

  • Pande, S.;Rao, J.Narayana
    • The Plant Pathology Journal
    • /
    • 제18권5호
    • /
    • pp.271-278
    • /
    • 2002
  • The effect of five plant population densities [5 (D$_1$), 10 (D$_2$), 20 (D$_3$), 30 (D$_4$), and 40 (D$_{5}$) plants/m$^2$] of four groundnut cultivars [ICGV 86699, ICG (FDRS) 10, ICGS 11 and TMV 2] and fungicide application (Kavach, chlorothalonil) to manage late leaf spot (LLS) and rust were studied in a field experiment during the 1995 and 1996 rainy seasons. LLS and rust severities were low in fungicide sprayed plots in all the cultivars irrespective of plant densities. Severities of LLS and rust, and percentage defoliation caused by LLS were significantly more in higher plant densities (D$_4$, D$_{5}$) than in lower plant densities (D$_1$, D$_2$, D$_3$) in fungicide sprayed and unsprayed plots in all the cultivars. All the cultivars gave significantly higher haulm and pod yields in fungicide sprayed plots than in unsprayed plots. Haulm and pod yields were significantly higher in higher plant densities than in lower plant densities. A combination of higher plant densities (D$_4$, D$_{5}$) and fungicide protection against LLS and rust gave maximum yield.yield.

Incidences of Leaf Spots and Blights on Kiwifruit in Korea

  • Jeong, In-Ho;Lim, Myoung-Taek;Kim, Gyung-Hee;Han, Tae-Woong;Kim, Hong-Chul;Kim, Min-Ji;Park, Hyun-Su;Shin, Soon-Ho;Hur, Jae-Seoun;Shin, Jong-Sup;Koh, Young-Jin
    • The Plant Pathology Journal
    • /
    • 제24권2호
    • /
    • pp.125-130
    • /
    • 2008
  • Various kinds of leaf spots and blights were found in kiwifruit (Actinidia deliciosa) orchards on 2006 in Korea. Disease incidences were quite variable between open-field and rain-proof shelter. Rate of diseased leaves was recorded as about 70% at open-field orchards in late season but use of rain-proof vinyl shelters alleviated the disease incidences by 20%. Angular leaf spots appeared at early infection stage on June and several other symptoms were also recognized as the disease developed afterward. On September, brown leaf blights were the most frequent, followed by grayish brown ring spots, silvering gray leaf blights, zonate leaf blights, dark brown ring spots and angular leaf spots at open-field orchards. Four fungal species were frequently isolated from the disease symptoms. Phomopsis sp. was the most predominant fungus associated with the leaf spot and blight symptoms on kiwifruit, followed by Glomerella cingulata, Alternaria alternata and Pestalo-tiopsis sp. Phomopsis sp. was commonly isolated from angular leaf spots, silvering gray leaf blights, and zonate brown leaf blights. G. cingulata, A. alternata and Pestalotiopsis sp. were isolated from grayish brown ring spots (anthracnose), brown ring spots and zonate dark brown leaf blights. Typical symptoms appeared on the wounded and unwounded leaves, which were inoculated by each of Phomopsis sp., G. cingulata, and Pestalotiopsis sp., but A. alternata caused symptoms only on the wounded leaves.

Epidemiology and Control of Strawberry Bacterial Angular Leaf Spot Disease Caused by Xanthomonas fragariae

  • Kim, Da-Ran;Gang, Gun-hye;Jeon, Chang-Wook;Kang, Nam Jun;Lee, Sang-woo;Kwak, Youn-Sig
    • The Plant Pathology Journal
    • /
    • 제32권4호
    • /
    • pp.290-299
    • /
    • 2016
  • Strawberry bacterial angular leaf spot (ALS) disease, caused by Xanthomonas fragariae has become increasingly problematic in the strawberry agro-industry. ALS causes small angular water-soaked lesions to develop on the abaxial leaf surface. Studies reported optimum temperature conditions for X. fragariae are $20^{\circ}C$ and the pathogen suffers mortality above $32^{\circ}C$. However, at the nursery stage, disease symptoms have been observed under high temperature conditions. In the present study, results showed X. fragariae transmission was via infected maternal plants, precipitation, and sprinkler irrigation systems. Systemic infections were detected using X. fragariae specific primers 245A/B and 295A/B, where 300-bp and 615-bp were respectively amplified. During the nursery stage (from May to August), the pathogen was PCR detected only in maternal plants, but not in soil or irrigation water through the nursery stage. During the cultivation period, from September to March, the pathogen was detected in maternal plants, progeny, and soil, but not in water. Additionally, un-infected plants, when planted with infected plants were positive for X. fragariae via PCR at the late cultivation stage. Chemical control for X. fragariae with oxolinic acid showed 87% control effects against the disease during the nursery period, in contrast to validamycin-A, which exhibited increased efficacy against the disease during the cultivation stage (control effect 95%). To our knowledge, this is the first epidemiological study of X. fragariae in Korean strawberry fields.

추낙답(秋落畓) 토양(土壤)에서 생육(生育)한 수도(水滔)에 대(對)한 규회석(珪灰石)의 효과 (The Effect of Wollastonite on Rice Plant Grown on an Akiochi Soil)

  • 박영대;김영섭
    • 한국토양비료학회지
    • /
    • 제1권1호
    • /
    • pp.61-71
    • /
    • 1968
  • 1. 추낙답토양(秋落畓土壤)에 생육(生育)한 수도(水稻)는 엽(葉)이 아래로 늘어지나 규산물질(珪酸物質)(규산가리(珪酸加里), 규산질비료(珪酸質肥料) 및 규회석(珪灰石))의 시용(施用)으로 수도(水稻)의 엽(葉)은 현저해 직립(直立)되었다. 2. 정조중(精租重)은 규산물질(珪酸物質)의 시용(施用)으로 증가(增加)하며 규회석(珪灰石)의 비효는 규산질비료(珪酸質肥料)보다 못하지 않았다. 3. 규회석(珪灰石)의 비효는 기비(基肥)로 시용(施用)하는 것이 좋으며 질소(窒素)의 증시효과는 규회석(珪灰石)의 증시(增施)에 의(依)하여 현저하다. 4. 수도(水稻)의 규산함량(珪酸含量)은 규산물질(珪酸物質)의 시용(施用)으로 증가(增加)하며 규산물질중(珪酸物質中)에서도 규회석(珪灰石)의 시용(施用)이 수도(水稻)의 규산함량(珪酸含量)을 가장 많이 증가(增加)시켰다. 수도(水稻)의 규산함량(珪酸含量)은 규회석(珪灰石)을 기비(基肥)로 시용(施用)하는 것이 증가(增加)하며 또 규회석(珪灰石)의 시용량(施用量)의 증가(增加)에 따라 증가(增加)하였다. 한편 수도(水稻)의 철(鐵) 및 질소함량(窒素含量)은 규산물질(珪酸物質)의 시용(施用)으로 감소(減少)되었다. 5. 규산물질(珪酸物質)의 시용(施用)은 엽도열병(葉稻熱病), 수수도열병(穗首稻熱病) 및 호마엽고병(胡麻葉枯病)의 발병(發病)을 저하(低下)시키며 규산물질중(珪酸物質中)에서도 규회석(珪灰石)의 효과가 가장 좋았다. 6. 엽도열병(葉稻熱病)의 이병율(罹病率)은 질소(窒素)의 증시(增施)에 비례(比例)하여 증가(增加)하나 규회석(珪灰石)의 시용(施用)으로 현저히 경감(輕減)되며 이 현상(現象)은 만식재배시(晩植栽培時)에 더 현저하다. 7. 호마엽고병(胡麻葉枯病)의 이병율(罹病率)도 규회석(珪灰石)의 시용량(施用量)이 증가(增加)함에 따라 현저히 경감(輕減)하였다.

  • PDF

Evaluation of Growth and Yield on Italian Ryegrass in Reclaimed Land

  • Yun-Ho Lee;Hyeon-Soo Jang;Jeong-Won Kim;Bo-kyeong Kim;Deauk-Kim;Jong-Tak Youn
    • 한국작물학회:학술대회논문집
    • /
    • 한국작물학회 2022년도 추계학술대회
    • /
    • pp.102-102
    • /
    • 2022
  • More than 74% of forage crops in Korea are cultivated in winter rice fields. Italian ryegrass (IRG) can be said to be a representative forage crop, but over 70% of its seeds are dependent on imports. In addition, there are concerns that the stable supply of research fees may be disrupted due to the effects of climate change, war, and other factors. Therefore, it is necessary to secure a large production area for stable supply. Korea's reclaimed land area is 135,000 ha and its agricultural area is 112,000 ha. Therefore, this study attempted to apply IRG to the domestic IRG seed industry through stable cultivation techniques on reclaimed land. In this study, IRG 'Kowiearly' varsity was cultivated in late October 2020 and early October 2021 in the Saemangeum reclaimed land. The seeding methods were conventional drill sowing seeding, new technology spot seedling (30 × 18 cm) and new technology drill sowing seeding. The amount of sowing was conventional drill sowing seeding 2.0(kg/10a), new technology spot seedling 1.5(kg/10a), and new technology drill sowing seeding 1.5(kg/10a). Fertilizer application amount is conventional drill sowing seeding(N-P2O5-K2O) 9.0-12-12(kg/10a), and new technology spot seedling and drill sowing seeding were(N-P2O5-K2O) 4.5-12-12(kg/10a) respectively. Fertilizer was applied accordingly. After that, in February, the conventional drill sowing seeding, new technology drill sowing seeding and spot seedling applied 4.0 and 2.2(kg/10a) of nitrogen supplement fertilizer, respectively. Before wintering, plant length was higher in 2022 than in 2021, but leaf number was higher in 2021. Heading time was April 30, 2021 and April 25, 2022. In heading time, plant length was 74 cm in 2021 and 67 cm in 2022, lower than in 2021. On the other hand, There was no difference in the number of panicle and the number of seeds in the 2021 harvester in all treatment plots, and, thus seed yield was no differ. However, the drill sowing seeding and spot seedling of the new technology were somewhat higher than the conventional drill sowing seeding. On the other hand, seed yield was decreased in all treatment plots compared to 2022 because of raifall deficiency in 2021.

  • PDF

1999-2008년도 벼 주요 병해 발생 개황 (Survey of Major Disease Incidence of Rice in Korea during 1999-2008)

  • 이용환;나동수;예완해;최효원;명인식;이세원;이영훈;한성숙;심홍식
    • 식물병연구
    • /
    • 제16권2호
    • /
    • pp.183-190
    • /
    • 2010
  • 1999년부터 2008년까지 우리나라에서 발생하는 벼의 주요 병해에 대한 발생상황을 조사하였다. 잎도열병은 2000년에 0.85%의 병반면적률을 보인 이후 2008년에는 0.02%로 지속적으로 감소한 반면에 이삭도열병의 경우에는 출수기부터 호숙기까지 그 해의 기상조건에 따라 불규칙적으로 발생하였다. 잎집무늬마름병은 2001년에 10.2%의 병반고율로 가장 적었고 2007년에 21.4%로 가장 많이 발생하였는데 8월 중순에서 하순 사이의 일조시간과 병반고율 사이에 상관계수가 $-.0.88^*$로 부의상관을 나타내었다. 깨씨무늬병은 충북, 경북, 경남 지방에서는 2001년에 발생이 심한 이후에 급격히 그 정도가 감소한 반면에 충남, 전북, 전남 지방에서는 2005년 이후로 발생이 증가하였다. 이삭누룩병은 2000년에 전국적으로 7.59%의 발병수율을 보인 후에 급격히 감소하였는데 출수기인 8월 하순의 강우량과 상관계수 $0.94^{**}$로 고도의 정의 상관을 나타냈다. 흰잎마름병은 전남, 전북, 경남, 충남의 상습지에서 2003년 이후로 심하게 발생하였다.

파를 가해하는 파굴파리의 충태별 피해 양상 및 행동 (Injury Aspects of the Stone Leek Leafminer, Liriomyza chinensis Kato (Diptera: Agromyzidae) on Welsh Onion)

  • 최인후;김정화;김길하;김철우
    • 한국응용곤충학회지
    • /
    • 제42권4호
    • /
    • pp.335-343
    • /
    • 2003
  • 파굴파리의 파 잎의 가해 습성을 조사한 결과 암컷성충은 잎의 외부에서 즙액을 섭취하고 엽육에 산란함으로서 피해를 주었다. 피해 잎은 직경 0.48mm의 백색 원형의 흡즙흔이 수십 개씩 점선을 형성하였고, 산란흔은 0.1${\times}$0.14mm 장타원형이고 1개 또는 수 개씩 V자형으로 무리를 지어 산란하였다 집단사육에서 성충의 흡즙은 우화당일에 시작하여 4-5일째에 가장 왕성하였고, 산란은 우화 2일부터 6일째까지 일별 산란수가 비슷하였다. 또한 흡즙과 산란은 밤보다는 낮에 더 활발하였다. 유충은 엽육에 갱도를 뚫고 엽의 위아래로 섭식하다가 밀도가 높고 발육이 진전되면 잎 끝쪽에서부터 아래쪽으로 이동하면서 잎을 고사시켰다. 유충 1마리의 식해량은 72.1$\textrm{mm}^2$이었다. 노숙유충이 잎에서 탈출하는 시간은 오전 5-7시이었고, 번데기는 토양깊이 5cm, 파측면 10 cm근처에서 대부분 용화하였다. 월동태는 번데기로 지표에서 토양깊이 10cm 이내에서 서식하였으며, 5월상순부터 6월하순까지 약 2개월 사이에 우화하였다. 성충은 잔존된 파, 묘상, 이식된 포장, 밭뚝 등으로 이동하여 생존하였다.

1992년도 경북북부지역의 담배병해 발생상황 (Disease Severity of Tobacco Plants Surveyed in the Northern Kyeongbuk Province in 1992)

  • 이영근
    • 한국연초학회지
    • /
    • 제15권1호
    • /
    • pp.15-25
    • /
    • 1993
  • The severities of major tobacco diseases had been surveyed throughout northern Kyeongbuk, a major flue-cured tobacco growing district in Korea, in relation to the actual control method used by the farmers in 1992. At seedling stage, anthracnose caused by Colletotrichum nicotianae was major disease of the plant due to poor damage of the temporary transplanting pots. Mosaic caused by tobacco mosaic virus(TMV) was very severe in certain of greenhouses. Although viral disease caused by TMV, cucumber mosaic virus(CMV) and by potato virus Y(PVY) were severe in fields, but mosaic by TMV was major of the diseases. Potato virus Y was found later than that in Honam district. The late occurrence of the disease might be caused the difference between cultivating method of potato plants in northern Kyeongbuk and that in Honam district. In fields suffered from hail disaster, the damage of tobacco plants by angular leaf spot was severe. Most of tobacco growers had wrong information about the practical methods not only of milk treatment for the protection of the plants from TMV, but also of fungicide applications for the control of other major diseases. It suggested that education on the methods to the farmers must be very important for control of the diseases.

  • PDF