EFFECT OF DIFFERENT SOURCES OF N-2 ON THE STRUCTURE OF MIMOSA-CAESALPINIAEFOLIA ROOT-NODULES

Mimosa caesalpiniaefolia is an N-2-fixing tree that grows quickly and is a multipurpose tree. In the nursery, the plant needs the maximizati on of growth. High levels of combined N-2 inhibit nodulation in many l egumes. Nodules or some species of trees grow slowly in comparison wit h grain legumes, and a small amount of N-2 can stimulate nodulation sh ortly after germination. The effect of different sources of N-2 on nod ule structure and plant growth was studied. Applied nitrate drasticall y affects the nodule structure. and reduces nodule number and plant gr owth. Plant growth parameters were clearly superior in the presence of NH4+ and it had no deleterious effect on nodule structure. (C) 1997 E lsevier Science Ltd.