SEASONAL AND DIURNAL VARIATION IN LEAF SESQUITERPENES OF GREENHOUSE-GROW SAPLINGS OF HYMENAEA AND COPAIFERA Phosphate Solubilization by Rhizobia Isolated from Woody Legume Plants in Hainan Island A STUDY ON NATURAL RESOURCES OF NODULATING TREE LEGUMES AND STRAINS OF RHIZOBIA Responses of Tree Legumes to Rhizobial Reinoculation A Preliminary Study on Nodulation and Nitrogen Fixation of Several Tree Legumes RECENT ADVANCES IN SYMBIOTIC NITROGEN FIXATION OF TREE LEGUMES