Effect of Azospirillum spp. inoculation on root development and uptake in wheat (Triticum aestivum cv. Miriam) in hydroponic systems

Abstract

Wheat (Triticum aestivum cv. Miriam) was grown in petri dishes and in vermiculite-filled pots. Inoculation with a mixture of Azospirillum brasilense strains Cd, Sp 7, and Cd-1, a local strain, significantly enhanced above noninoculatcd controls the root length and branching. In a hydroponic system containing [Formula: see text], the surface area of roots and the uptake of [Formula: see text] from the mineral solution during plant growth were increased by inoculation. However, no significant changes were obtained in the [Formula: see text] uptake – root surface area ratio. Heading and flowering occurred earlier in the inoculated plants as compared with the noninoculated plants. Total shoot and root weights, plant height, the number of fertile tillers, and grain yield were significantly increased by inoculation. The inoculated roots did not show any nitrogen fixation activity. It was concluded that under these experimental conditions, the benefits obtained in wheat inoculated with Azospirillum are mainly derived from an enhancement of root development and the amount of [Formula: see text] taken up by the roots.