Compost hygienisation

I made a small study on the regulation of compost hygienisation. There is a lot of literature on this topic, but taken together, the results are quite confusing. I present here one example.

One of the diseases considered a persistent problem for composting is clubroot, caused by Plasmodiophora brassicae. In various recommendations about this topic, it seems that the higher the temperature/time profile the better the inactivation is. However, if all information on this is summarized in a figure (see above), then the picture is not so evident. In several cases a low temperature and/or short incubation time also resulted in inactivation (green dots), and in one case even a higher temperature/time profile did not lead to inactivation (red dots). To my opinion this indicates that the mechanisms of inactivation is not covered by the temperature/time profile. Other factors are likely involved, perhaps compost moisture content. Also the method by which researchers determine inactivation conditions may affect the recommendations as explained by Wichuk & al. (2011). The data are based on the review by Wichuk & al., 2011, Compost Sci. Util. 19: 244-266.