APPLICATION OF GLUCOSE AT LOW CONCENTRATIONS TO GRASS SWARDS IN WASTE-DERIVED COMPOST CAN SIGNIFICANTLY INCREASE LONG-TERM YIELDS

Carbohydrates have a range of effects on soil, dependent the frequency and concentration of the application. Small quantities of glucose hav e the effect of accelerating the removal of available N (NH4+, NO3-) t hrough incorporation into the bodies of microorganisms. This reduces p lant growth (Jenkinson, 1985), the rate of which depends largely on th e presence of available N (Addiscott et al., 1991). However, in theory , if appropriate soil glucose concentrations are maintained, asymbioti c N-2-fixation will occur, supplying extra nitrogen nutrition to plant s over an extended period. Here, it is demonstrated that the use of 0. 028M glucose and an appropriate source of N-2-fixing bacteria (green w aste-derived compost) can result in increased grass dry matter yields of over 50% in a glasshouse experiment.