Enhancement of symbiotic growth and yield of vegetable soybean by co-inoculation with Azospirillum and Bradyrhizobium - Shamsuddin, Zulkifli; Rahman, Md. Motior; Wan Othman, Wan Mohamad; Puteh, Adam; Mohd Saud, Halimi; Wong, Kai Choo; Mahmood, Marziah