As regular readers of this blog will know, I have more than a passing interest in soil micro-organisms and, sometimes, there is a bit of research elsewhere that implies a similar link between bacteria and a particular condition or disease, and of some further understanding of how things work. There has been report in Nature Microbiology recently that certain gut bacteria (Dialister and Coprococcus) are present in lower numbers in people who experience depression and that there is growing evidence that there is a link between the lack of these bacteria, inflammation and the mood disorder, i.e. these bacteria are good guys.
Similarly in soils, while we have known that the presence of particular bacteria can cause disease, we are only just beginning to learn about soil bacteria which will depress crop disease risk and enhance growth. For example, we know that when a crop is sprayed with selective herbicide, that some species of mycorrhizae (soil fungi), under the right circumstances, can take water and nutrients from the weakened weeds and transfer them into the crop roots/ The right circumstances? Well, at least part of that looks like high organic matter in the soil.
Bill Butterworth, Land Research Ltd. 15 March 19.