• Title/Summary/Keyword: powdery mildews

Search Result 24, Processing Time 0.019 seconds

Anamorphic Morphology in Three Oriental Species of Microsphaera (흰가루병균(病菌) Microsphaera속(屬)에서 동양(東洋) 3종(種)의 무성세대(無性世代) 형태(形態))

  • Shin, Hyeon-Dong
    • The Korean Journal of Mycology
    • /
    • v.21 no.2
    • /
    • pp.120-126
    • /
    • 1993
  • Morphological characteristics in the anamorphic states were described in three species of powdery mildew fungi, Microsphaera akebiae, M. picrasmae and M. schizandrae, which were parasitic on Akebia quinata, Picrasma quassioides, and Schizandra chinensis, respectively. All species were flexuous in foot-cells of conidiophores, producing conidia singly on conidiophores, devoid of fibrosin bodies in conidia, and producing germ tubes on the end of conidia.

  • PDF

Taxonomy of the Golovinomyces cynoglossi Complex (Erysiphales, Ascomycota) Disentangled by Phylogenetic Analyses and Reassessments of Morphological Traits

  • Braun, Uwe;Bradshaw, Michael;Zhao, Ting-Ting;Cho, Sung-Eun;Shin, Hyeon-Dong
    • Mycobiology
    • /
    • v.46 no.3
    • /
    • pp.192-204
    • /
    • 2018
  • The name Golovinomyces cynoglossi s. lat. is traditionally applied to a complex of morphologically similar powdery mildews on hosts of the plant family Boraginaceae. The current species-level taxonomy within this complex is ambiguous due to the lack of phylogenetic examinations. The present study applied phylogenetic methods to clarify the taxonomy of G. cynoglossi s. lat. Phylogenetic analysis of rDNA ITS sequences retrieved from Asian, European and North American specimens revealed that G. cynoglossi s. lat. collections from different hosts involved several species in five clearly separated lineages. Clade I consists primarily of Golovinomyces cynoglossi s. str. on Cynoglossum. Clade III consists of Golovinomyces sequences retrieved from the host genera Symphytum and Pulmonaria. The taxa within clade III are now assigned to G. asperifoliorum comb. nov. Clade V encompasses G. cynoglossi s. lat. on the host genera Bothriospermum, Buglossoides, Echium, Myosotis, and Trigonotis. The taxa within clade V are now assigned to G. asperifolii comb. nov. The species concerned in this study were lecto- and epitypified to stabilize their nomenclature.

Control of Powdery Mildew by Foliar Application of a Suspension of Cheonggukjang (청국장 현탁액 오이 엽면처리에 의한 흰가루병 방제효과)

  • Kim, Min-Jeong;Shim, Chang-Ki;Kim, Yong-Ki;Hong, Sung-Jun;Park, Jong-Ho;Han, Eun-Jung;Jee, Hyeong-Jin;Kwon, Jin-Hyeuk;Kim, Seuk-Chul
    • Research in Plant Disease
    • /
    • v.21 no.2
    • /
    • pp.58-66
    • /
    • 2015
  • This study was conducted to evaluate control efficacy of a fermented food 'Cheonggukjang' against cucumber powdery mildew caused by Sphaerotheca fuliginea in greenhouse. Sterilized Daepung beans were inoculated with the rice straw as natural inoculum and then incubated for 72 hrs at $42^{\circ}C$ in the household cheonggkjang maker. After 72 hrs of cheonggukjang fermentation, white zymogens were grown on the surface of a sterile Daepung beans. The pH of the 72 hrs fermented soybean was not significantly changed and electrical conductivity was found to increase by about 2 times than before fermentation. The population density of soybean zymogen showed a peak of growth at 60 hrs after fermentation and the concentration of zymogen was $8.2{\times}10^7cfu/ml$. Soybean zymogen form of the colony was divided into three kinds of bacteria and a white and a large colony (WL) was predominant bacteria among those up to 60 hrs of fermentation. To control the cucumber powdery mildew, diluted solutions of cheonggukjang was applied from 6.0% to 30.0% on cucumber leaves and they showed injury symptoms on cucumber leaves in more than 15% of them. However, more than 6.0% diluted cheonggukjang solutions showed more than 77.8% control effect of cucumber powdery mildew at 15 days after treatment. The fermented bacteria of Chenggukjang were well established in the cucumber leaf area at 15 days after treatment. The antifungal activity of 10% diluted cheonggukjang solutions was excellent for four species of plant fungal pathogens, Colletotrichum gloeosporioides, Sclerotinia cepivorum, Rhizoctonia sloani and Phytophthora capsici in the dual culture test. Results indicated that foliar application of Cheonggukjang solution could be used for the control of powdery mildews occurring on organically cultivated cucumber.

Effect of Waterlogging during Fruit Enlargement on the Quality and Yield of Oriental Melon (Cucumis melo L. var. Makuwa Mak.) (과실비대기 담수처리가 참회의 품질 및 수량에 미치는 영향)

  • 신용섭;연일권;최진국;최성국;최부술
    • Journal of Bio-Environment Control
    • /
    • v.9 no.3
    • /
    • pp.141-145
    • /
    • 2000
  • This experiment was carried out to investigate the influence of flooding on the quality and yield of an oriental melon. Waterlogging for four periods, 0(not flooded), 5, 10 or 15h, were applied to 30cm depth from the soil surface. The soluble solids content of fruit flesh measured at 7 days after waterlogging was 12.6 Brix in not-flooded plot, but it decreased by 4.7-5.6 Brix in plots flooded 5, 10 or 15h, respectively. Difference in fruit hardness between the no-flooded and 5h-flooded plots was not observed, while a significant decrease in fruit hardness was observed in 10 or 15 h-flooded plots at 7 days after waterlogging. Decrease in fruit hardness in all plots except control plot was observed at 13 days after waterlogging. The percent decayed fruits at 7 days after waterlogging was not observed, but at 13 days after waterlogging it gradually increased as duration of flooding increased. The incidence of downy or powdery mildews increased is significantly in plots flooded for 5, 10 or 15h as compared to the not-flooded control. However, population of cotton caterpillar decreased in the flooded plots. Marketable fruits yield per 10a was 616.2kg in no-flooded plot, but it decreased by 33%, 45% and 66%, respectively, in plots flooded for 5, 10 or 15h. The waterlogging during fruit enlargement stage significantly deteriorated fruit quality and decreased marketable fruit yield.

  • PDF