dc.description.abstract | The utilization of acid mineral soil often faces the problem of Al toxicity and low available P. The efforts to improve root function and neutralize the effect of high available Al are becoming important for increasing the growth of legumes, particularly as the cover crops at the plantation on acid soil. This research was aimed to find the effect of VA mycorrhyza inoculation, rhizobium, and humic acid on the growth and nutrient content offour different legume species. It was a three factor factorial experiment arranged in a completely randomized design with three replications. The first factor was four legume species: Calopogonium mucunoides, Calopogonium ceurelieum. Centrosema puhescens and Pueraria javanica; the second factor was four different inoculants: none (MaJ, MVA (MJ, rhizohium (Mz), MVA+rhizohium (MJJ; the thirdfactor was two rates of humic acid application: without (HaJ and with humic acid (HJ. The results proved the positive effect of those three factors on the growth of shoot and roots. The responses of root growth on microorganism inoculations and humic acid were different among the legume cover crop species. The role of humic acid was significantly better if there was a synergism between MVA and rhizobium. | id |