Combined Effect of Phosphate-Solubilizing Microorganisms, Rhizobium and Enterobacter on Root Nodulation and Physiology of Soybean (Glycine max L.)

摘要

Although phosphate-solubilizing microorganisms play a positive role in plant growth, their role in plant growth and root nodulation in combination with Rhizobium and Enterobacter has not been fully elucidated. Furthermore, only information exists regarding the effect of inoculation at successive stages of nodulation. The present study aimed to monitor the changes in the production of Indole acetic acid (IAA) and Gibberellin (GA(3)) in the roots of soybean during and after nodulation (25 DAS and 40 DAS) and in the rhizosphere soil following inoculation with two different strains of phosphate-solubilizing microorganisms (PSM I, strain CA 18 and PSM II, strain 54RB), Enterobacter strain A and BradyRhizobium Japonicum strain Tal 377. The effects of inoculation on the available NO-3, K, and P content of soil were studied at harvest. Beneficial effects of inoculation with Rhizobium, Enterobacter, and PSM I and II were obtained in all growth parameters of soybean. Co-inoculation resulted in maximum increase in IAA and GA content, plant biomass, root nodulation, number, weight and length of pods as compared with control (non-inoculated) and single-inoculation plants. The soil of the inoculated plants also showed higher IAA and GA content overC1 [Yasmeen, Samina; Bano, Asghari] Quaid I Azam Univ, Dept Plant Sci, Phytohormone Lab, Islamabad, Pakistan.RP Bano, A (reprint author), Quaid I Azam Univ, Dept Plant Sci, Islamabad, Pakistan.EM asgharibano@yahoo.comNR 48