Effects of Nutritional Factors on Chemical and Soil Microbiostasis

Microorganisms including fungi, actinomycetes, and bacteria remain quiescent or decrease in number when they are introduced into natural soil. Such microbiostasis is a general phenomenon of natural soil. Tables list the nutritional factors that are capable of decreasing or increasing soil microbiostasis, and also the microorganisms tested. Those nutrients shown to be ineffective are also included. The majority of reports concerning the effects of nutritional factors on inhibition of microorganisms dealt with the inactivation of antimicrobial agents, and only a few cases of enhancement of antimicrobial activity of chemicals by nutrients were documented. The effects of nutritional factors on fungistasis was most extensively studied among the three types of soil microbiostasis, followed by bacteriostasis and antinostasis. Agar, sulfur-containing amino acids, vitamins, and mineral salts which are very effective in inactivating considerable numbers of antimicrobial agents are, in general, ineffective in annulment of soil microbiostasis. These differences suggest that soil microbiostasis is not due to chemical inhibition