Harvest Management Effects on Dinitrogen Fixation and Nitrogen Transfer in Red Clover-Orchardgrass Mixtures

Abstract

The role of harvest management on the N nutrition of perennial forage legume-grass mixtures requires further investigation. Closer examination would provide a better understanding of the roles of defoliation, N 2 fixation, and N-transfer in the management of red clover (Trifolium pratense L.)-orchardgrass (Dactylis glomerata L.) mixtures. Periodic harvesting of shoots of forage legumes removes a primary source of energy for maintaining N 2 fixation. Nodule structure and function and the initiation of new nodules is affected, also. The ability of nodules to remain functional after removal of the vegetative shoots may depend upon a number of factors (e.g., plant species, microsymbiont, nodule morphology, rate of shoot regrowth, nutrient availability, and competition between plant parts for energy) [...]