Abstract
Tobacco leaf discs inoculated with a standardized suspension of endoconidia ofThielaviopsis basicola (Berk. & Br.) Ferr. were floated on tap water and on different concentrations of benomyl suspension. Lesion rating was 0.5, 0.25 and trace on 0.5-, 1- and 5-ppm benomyl concentration, respectively, as compared with 4.0 for the check. No lesions were formed on 10- and 50-ppm concentrations. Benomyl protected tobacco leaf discs systemically against lesion formation when applied before the penetration of the germ tubes. It also suppressed the development of mycelium on the necrotic spots.
The bearing of these results on the relation between leaf and root necrosis, is discussed.
Samenvatting
Schijfjes tabaksblad dreven op leidingwater met verschillende concentraties benomylsuspensie. De bladeren waren geïnoculeerd met een gestandaardiseerde endoconidiënsuspensie vanThielaviopsis basicola. De verhouding van de lesies in de schijfjes op water met resp. 0.5, 1 en 5 ppm benomyl was 0.5, 0.25 en zeer weinig, vergeleken met 4.0 bij de controle. Er werden geen lesies gevormd op een benomylconcentratie van 10 en 50 ppm. Benomyl beschermde de schijfjes tabaksblad systemisch tegen lesievorming, als het vóór het binnendringen van de kiembuizen werd toegediend. Het onderdrukte ook de myceliumontwikkeling op de necrotische plekken.
De betekenis van deze resultaten voor de relatie tussen blad- en wortelnecrose wordt besproken.
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References
Clemons, G. P. & Sisler, B. F., 1969. Formation of a fungitoxic derivative from Benlate. Phytopathology 59: 705–705.
Fokkema, N. J., 1968. The influence of pollen on the development ofCladosporium herbarium in the phyllosphere of rye. Neth. J. Pl. Path. 74: 159–165.
Gayed, S. K., 1969. The relation between tobacco leaf and root necrosis induced byThielaviopsis basicola and its bearing on the nature of tobacco resistance to black root rot. Phytopathology 59: 1596–1600.
Hecht, E. I. & Bateman, B. F., 1964. Non-specific acquired resistance of pathogens resulting from localized infections byThielaviopsis basicola or viruses in tobacco leaves. Phytopathology 54: 523–530.
Szirmai, J., 1940. Untersuchungen und Beobachtungen an “necrotic virus” im Zusammenhang mit dem Pilz Thielavia basicola Zopf. Phytopath. Z. 12: 219–227.
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Contribution 53, Delhi Research Station.
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Gayed, S.K. The effect of benomyl on tobacco leaf necrosis induced by Thielaviopsis basicola. Netherlands Journal of Plant Pathology 76, 125–128 (1970). https://doi.org/10.1007/BF01974317
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DOI: https://doi.org/10.1007/BF01974317