Abstract
A new technique for the quantitative detection of Chalara elegans and C. thielavioides in soil based on the combination of a soil dilution technique with carrot disc baits was developed. The quantitative Chalara test was validated in replicated experiments using mineral and organic soils in our laboratory. The test allowed detection of a population density of 1 cfu 0.1 gt-1 fresh soil. Efficiency, repeatability and dependability of the test were regarded as acceptable and this was confirmed by an international ring test with 7 participating laboratories. With the quantitative Chalara test, the influence of crop cultures or green manures on the population densities of C. elegans and C. thielavioides in the soil can be assessed.
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Heller, W.E. A new method of quantitative detection of Chalara elegans and C. thielavioides in soils using carrot discs. J Plant Dis Prot 119, 169–173 (2012). https://doi.org/10.1007/BF03356437
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DOI: https://doi.org/10.1007/BF03356437