Behaviour of Streptomycetes in Soil

SUMMARY Most of the conidia from eight different streptomycetes did not germinate in natural soil under conditions apparently suitable for their germination. When germinated in nutrient solution and then added to soil, they grew for a limited period, sporulated and then the vegetative hyphae disappeared, leaving behind only spores. Streptomycete conidia produced naturally in garden soil decreased in number by about a half after 12 days. Nevertheless, the conidia are the main means of survival and it appears that streptomycetes exist in soil mainly as spores. Mycelia also existed, but in the main were restricted to micro-sites where nutrient was available.