Int. J. Bioinformatics and Biological Sci.: v.2 n.1&2, p. 95-109. March and June 2014

characterisation of Plant growth Promoting Endophytic

Bacteria Isolated from Lens culinaris medik with

antagonistic Potential against Fusarium Oxysporum

Swarnita Dixit 1* , R. c. Dubey 1 and P. K. Seth 2

1 Department of Botany and Microbiology, Gurukul Kangri University, Haridwar-249404

Uttarakhand, India.

2 Biotech Park, Sector G, Jankipuram, Kursi Road, Lucknow-226021,

Uttar Pradesh, India.

*Corresponding author: Swarnita Dixit; swarnitadixit@gmail.com

abstract

A total of 152 endophytic bacterial isolates belonging to Rhizobium , Pseudomonas

and Bacillus spp. were isolated from the root nodules of Lens culinaris from seven

different provinces of Uttar Pradesh (India) growing in different soil condition

of varying pH 6.8-7.8. These isolates were characterized morphologically,

physiologically and biochemically, and screened in vitro for their plant growth

promoting traits such as production of indole acetic acid (IAA), ammonia (NH ₃ ),

hydrogen cyanide (HCN), siderophore, phosphate solubilization and antifungal

activity against Fusarium oxysporum . Only 27 endophytic showed positive

results for all plant growth promoting attributes and antagonism against Fusarium

oxysporum. All physio-biochemical characters including carbon utilization were

analyzed by a Jaccard’s coefficient dendrogram, that classified the isolates into the

three major groups viz., RT1, RT9-RT16, RT26 and RT27 isolates in one group,

RT2-RT8, RT17-RT18, RT24 and RT25 isolates in second group, and RT19 - RT23

isolates in third group. On the basis of UPGMA cluster analysis and similarity

with the standard strains these isolates were identified as Rhizobium strains RT1,

RT9-RT16, RT26, RT27, Pseudomonas strains RT2-RT8, RT17-RT18, RT24 and

RT25, and Bacillus strains RT19 - RT23. The strains RT1, RT2 and RT11 showed

synergism among them and also found to possess plant growth promoting and

antagonistic properties.

Keywords: Plant growth promoting rhizobacteria, Endophytic bacteria,

Antagonism, Bacillus , Rhizobium , Pseudomonas , Lens culinaris.

Plants constitute vast and diverse niches for endophytic organisms. Bacterial

endophytes show great diversity not only in term of plant hosts but also in bacterial

phyla (Bacon and Hinton, 2006). They inhabit majority of healthy and symptom-

less plants. The bacterial taxa isolated from the endorhizosphere niches consist of