We understand that organisms which are called ‘pathogens’ can be present in the soil, on the leaf surface, and even inside the plant without causing disease, without being virulent.

We know that there are a number of factors which can trigger virulence. The factors can be related to microbiome diversity, nutritional integrity or climactic stress. We can pool these factors together and term them ‘environment’.

This is the basis for the quote “Environment determines genetic expression”, in regards to potentially virulent organisms.

The question we should be asking is “What is the environment required for this specific organism to become pathogenic?”.

The question Olivier Husson has been asking is “What is the model that universally describes when plants and soil are the corect environment for organisms to become pathogenic?”

I am excited to introduce you to the MUST READ paper that answers this question. There is more valuable information contained in this paper than I can properly introduce in short post. Please read it. You will be delighted.

This paper is a longer read at 57 pages. Print it, spend some time with it. You will be glad you did.