XVI International Botanical Congess

The effect of P and N in nodulation and growth parameters of Discaria americana seedlings was studied. Pots containing rizosphere-soil from a population of Discaria americana was pretreated in pots during 13 weeks with 3 levels of P (0.5mM,10mM and 100 mM) . Five seedlings of D. americana were transplanted to each pot and drenched during 8 month with nutritive solution without and with nitrogen (0.09 mM NH4NO3). Number of nodules, dry weight of nodules and plants, and height of plants were recorded. P caused a significant increase in plant growth parameters and results suggest that 50 mM provide the highest perfomance. Regarding N, no significant differences were observed.