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 have the effect of accelerating the removal of available N (NH4+, NO3-) through incorporation into the bodies of microorganisms. This reduces plant growth (Jenkinson, 1985), the rate of which depends largely on the presence of available N (Addiscott et al., 1991). However, in theory, if appropriate soil glucose concentrations are maintained, asymbiotic N-2-fixation will occur, supplying extra nitrogen nutrition to plants 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 waste-derived compost) can result in increased grass dry matter yields of over 50% in a glasshouse experiment.