The systemic action of dimethyldithilocarbamates on cucumber scab caused byCladosporium cucumerinum and the conversion of these compounds by plants

Abstract

covered with filter paper. The condensation-water evaporated from the filter paper by those parts which projected fi'om the glass box. After two days the strips showed a light red colour caused by growth of the fungus except on the spots which contained a fungitoxic compound. When necessary for quantitative purposes the inhibition zones were measured by a planimeter. e. Paper-spot bioassaySap to be tested for fungitoxicity was added to one spot of a strip of WHAT-MAN 3MM paper. The diameter of the spot was about 0.5 cm. The spot was dried in an air-current at 30~ The paper, placed on a metal frame, was sprayed with a conidial suspension of G. cingulata and incubated as described under d. The areas of the inhibition zones were measured by a planimeter. f. Dimethyldithiocarbamates

Studies on the fate in plants of ethylenebisdithiocarbamate fungicides and their decomposition products

“…Dialkyldithiocarbamates have been shown to form an alanine derivative and a /3-glucoside in plant tissue (Dekhuijzen, 1964;Kasiander et at. 1961Kasiander et at.…”

“…Before chromatography proteins were partly removed from the sap by adding an equal volume of 96% ethanol; the supernatant liquid was used. Bioassays of chromatograms were performed according to Dekhuijzen (1961Dekhuijzen ( , 1964 using thin-layer plates (Merck DC-Fertigplatten or DC-Alufolien) instead of paper. Conidia of Cladosporium cucu merinum were used instead of Glomerella cingulata.…”

“…However, fungicides have received comparatively little attention. Although the fate of dialkyldithiocarbamate fungicides (I) in plant material has been elucidated to a large extent (Dekhuijzen, 1961(Dekhuijzen, , 1964Kaslander, Kaars Sijpesteijn & van der Kerk, 1961Kaslander, 1966), there is little information about substances formed (ETU) Tomizawa (1960), working with isotopically labelled zinc ethylenebisdithiocarbamate (zineb, 11, X = $Zn), found two new labelled compounds in extracts of cucumber plants after root application. They presented chromatographic evidence that one of these compounds was ethylenethiourea (ETU,111).…”

Residue Reviews / Rückstands-Berichte

“…Compounds of pesticidal sprays may act in a similar complex manner since growth activities are known both of pesticidal compounds (ÄBERG 1960, JÖNSSON 1961, PLUIJGERS and VAN DER KERK 1961,DEKHUYZEN 1964 and of other components of the formulated product (CROSBY and VLITOS 1961, JANSEN 1961, STOWE 1961.…”

Polyphenols and natural resistance of apple leaves against Venturia inaequalis

“…The fungitoxicity of samples withdrawn from incubation mixtures of phloridzin and apple leaf enzyme, or homogenates of apple leaves, was estimated in two ways. The samples were chromatographed and the chromatograms bioassayed with various test fungi according to the method of Dekhuijzen (1964) fungi kept their viability after having been present during enzymatic oxidation of phloridzin. However, when conidia first had been germinating for 18 h and then were added to incubation mixtures of phloridzin and apple leaf enzyme, they were sensitive to oxidized phloridzin.…”