Co-Authors:
Sivan, J., Israel Institute for Biological Research, Nes Ziyyona, Israel
Barkai-Golan, R., Div. of Fruit and Vegetable Storage, ARO, The Volcani Center, Bet Dagan, Israel
Abstract:
Maneb was the most efficient chemical in inhibiting germination of Stemphylium botryosum f. lactucae spores in vitro. At 0.1 ppm it inhibited germination of all spores in the original population. Growth on PDA was markedly inhibited by 100 ppm daconil or maneb, with ca. 90-95% spore mortality. The inhibitory effects of chemicals at sublethal doses on the rate of colony growth resulted both in retarded radial growth and in prolonged incubation period in culture. Maneb at 100 ppm and daconil at 104 ppm had an inhibitory effect on inoculated leaf discs only when applied immediately after inoculation, whereas sodium dimethyldithiocarbamate (SDMC) inhibited fungal development at 104 ppm both immediately after inoculation and 24 h later. SDMC kept the tissue very fresh during the experimental period. Fungal development in inoculated lettuce heads was prevented by 103 ppm maneb or SDMC when applied before inoculation, but not when applied 24 h after inoculation, although in in vitro tests germinating spores were more sensitive to maneb than non-germinating ones. © 1976, Springer Science + Business Media B.V.. All rights reserved.