Abstract: | Summary There is growing interest in the presence of certain naturally-occurring, beneficial microorganisms in agricultural wastes (e.g., processing wastes, composts and anaerobic slurries) that have considerable potential to enhance the growth, health and protection of crops. The numbers of these organisms can be increased through incubation procedures and they can be applied as mixed or pure culture inoculants to soils and plants in waste materials or as sprays and suspensions. The various mechanisms of disease control and plant protection imparted by these beneficial microorganisms may be related to (a) microbe-microbe interactions, (b) plant-microbe interactions, (c) metabolites produced and /or, (d) induced systemic-acquired resistance. Research is needed to elucidate their exact mechanisms or modes-of-action to determine the optimum time, rate and frequency of application for improving plant health and protection. |