Effectiveness of simultaneous application of indigenous rhizobium and arbuscular mycorrhiza on root rot disease and yield of red bean (Phaseolus vulgaris L.) in Lorestan Province

Fusarium root rot of common beans is an important economic disease in Iran. It is broadly suggested that farmers use ecofriendly methods of plant disease management, compatible with the sustainable agriculture to minimize the application of pesticides in the fields. The current study was conducted to investigate the effectiveness of native rhizobium, mycorrhiza and chemical treatment. The experiment was carried out in a randomized complete block design in a field experiment at Sarab Changaie Research Station in 2017 with Ofogh red-bean cultivar. The trial treatments exerted as follow, superior native rhizobium isolate Rhizobium etli b.v. phaseoli (CCSM_B011401)(R), Rhizophagus irregularis(M2), Rhizophagus irregularis + Funneliformis mosseae (M1+M2), R. irregularis + F. mosseae + R. etli b.v. phaseoli (R+M1+M2), R. irregularis + R. etli b.v. phaseoli (R+M2), fungicide treatment and control.Rhizobium powder was applied as seed treatment and mycorrhiza was added directly in seedbed during the sowing of seeds. The best result was achieved from co-inoculation of arbuscular mycorrhiza fungi and indigenous rhizobium, which showed a significant increase of the number of seeds per pod, 100 seeds weight, grain yield and biomass yield as 34, 24.9, 51.6 and 38 percent compared to control. In addition, the co-inoculation treatment reduced the incidence of bean root rot disease up to 89%. Results indicated that the synergism of indigenous rhizobia and arbuscular mycorrhiza could be useful for managing of common bean root rot disease, reducing the use of pesticides and producing the crop in a sustainable and optimized manner.