To investigate the effect of some biological and chemical fertilizers on the root physiological and growth indexes and also Sorghum grain yield, this study was carried out in randomized complete block design with three replicates. The treatments of the study included (1) arbuscular mycorrhizal fungus Glomus mosseaeþvermicompost, (2) mycorrhiza fungusþNitroxin, (3) mycorrhiza fungusþ Rhizobium sp., (4) mycorrhiza fungusþNPK chemical fertilizer (40-40-20), (5) mycorrhiza fungus, and (6) control treatment. The highest root colonization rate and specific root length were observed in the co-inoculation with mycorrhizaþNitroxin treatment. The other root growth parameters were observed at the mycorrhizaþvermicompost treatment. Also the highest rate of Sorghum physiological growth indexes root such as root area index and net assimilation rate were belonged to the coinoculation of mycorrhizaþNitroxin treatment. The highest root growth rate and root relative growth rate were obtained in the mycorrhizaþvermicompost treatment. So it can be concluded that biological fertilizers can be used as an appropriate alternative for chemical fertilizers in sustainable agriculture system.

Keywords