Int.J.Curr.Microbiol.App.Sci (2016) 5(8): 59-70 59 Original Research Article http://dx.doi.org/10.20546/ijcmas.2016.508.007 Plant Growth Promoting Endophytic Bacteria from Zyzypus mauritiana Mayuri C. Rathod 1 and D.A. Dhale 2 * 1 Department of Biotechnology, Veer Narmad South Gujarat University, Surat- 395007, (Gujarat) India 2 PG-Department of Botany, SSVPS’s, L.K.Dr.P.R.Ghogrey Science College, Dhule-424005, (Maharashtra) India *Corresponding author ABSTRACT Introduction Bacterial endophytes were first discovered in Germany in 1903 (Freeman, 1903; Tan and Zou, 2001). Endophytic bacteria can be defined as those bacteria that colonize the internal tissue of the plant showing no external sign of infection or negative effect on their host (Holliday, 1989; Schulz & Boyle, 2006), and of the nearly 3,00,000 plant species that exist on the earth, each individual plant is host to one or more endophytes (Strobel et al., 2004). Only a few of these plants have ever been completely studied relative to their endophytic biology. The first report of presence of bacteria resident within the tissues of healthy plants was reported in 1926 (Hallman et al., 1997). Perotti recognized endophytic growth as a particular stage in the life of bacteria, described as an advanced stage of infection and as having a close relationship with mutualistic symbiosis. Perotti (1926) was the first to describe the occurrence of non pathogenic flora in root tissues. Since then, endophytes have been defined as microorganisms that could be isolated from surface-sterilized plant organs. Since there have been numerous reports on endophytic International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 5 Number 8 (2016) pp. 59-70 Journal homepage: http://www.ijcmas.com Plant growth-promoting bacteria are bacteria that can enhance plant growth and protect plants from disease and abiotic stresses through a wide variety of mechanisms; those that establish close associations with plants, such as the endophytes, could be more successful in plant growth promotion. Bacteria on roots and in the rhizosphere benefit from root exudates, but some bacteria and fungi are capable of entering the plant as endophytes that do not cause harm and could establish a mutualistic association. This study was conducted with a view to isolate bacteria associated with the roots and leaves of Zyzypus muritiana and to assess their functional potentialities in relation to plant growth promoting activities. Eighteen bacterial isolates were obtained from surface sterilized healthy roots and leaves of the plant. The isolates were tested for morphological and biochemical characteristics. The results of in vitro assays showed that all isolates can produce IAA, solubilize rock phosphate. These isolates having abilities for IAA production and phosphate solubilization were tested as bioinoculant to Z. muritiana roots. Keywords Endophytic bacteria, Bioinoculant, Rhizosphere, Zyzypus Muritiana. Accepted: 06 July 2016 Available Online: 10 August 2016 Article Info