SIGNIFICANCE OF TIMING AND INOCULATION WITH RHIZOSPHERE WHEAT PLANTS LEVEL OF BACTERIA ON

Summary-The importance of time of inoculation and bacterial concentration in the inoculum on the response of wheat plants was evaluated, using eight strains of rhizosphere bacteria. The optima1 bacterial concentration, for all strains, was 105-IO6 colony forming units ml-‘. Plant response was highest when seeds had been inoculated but was less when seedlings were inoculated. Successive inoculations somewhat increased plant response. Early inoculations resulted in an increased colonization of plant roots at later stages of growth. It was concluded that time of inoculation and the concentration of bacteria in the inoculum were of significant importance in plant response to inoculation and they may govern the inconsistency found in inoculation experiments using beneficial bacteria.