Journal of Microbial & Biochemical Technology

Biochemical and molecular characterization of fluorescents Pseudomonas spp.: Study of their potentialities to control Verticillium dahliae Kleb

3^rd World Congress and Expo on Applied Microbiology

November 07-09, 2016 Dubai, UAE

Tihar-Benzina F, Sahir-Halouane F and Oulebsir-Mohand Kaci H

Université de M�??Hamed Bougara, Algeria

Posters & Accepted Abstracts: J Microb Biochem Technol

Abstract:

Our research topic fits into the context of biological control which can be considered as a potential alternative to chemical control. The studies we conducted were designed to isolation and identification and the selection Pseudomonas spp. fluorescent group for their use against this phytopathogenic fungus. The surveys carried out during the 2012-2014 agricultural partner in several groves located in Boumerdes, Bouira and Tizi Ouzou showed the presence of fungal diseases that has vascular Verticillium. Isolated fluorescent Pseudomonas was screened using the antagonism in vitro and in situ test. The five selected isolates significantly reduced the mycelia growth and the formation of microsclerotia of V. dahlaie. The effectiveness of selected strains is then evaluated in pots under green house; the incidence and the severity of Verticillium wilt showed after bacterial inoculation of the roots of tomato plants were significantly reduced compared to the control treatment. The ability of the two best isolates of Pseudomonas PF49 and PP30 to protect tomato against the invasion of the fungus was confirmed, a relative PGPR effect was observed; especially in the last stages of culture. The genetic identification of best Pseudomonas isolates by sequencing the 16S RNA, allowed us to confirm the heterogeneity of our collection. Four main groups were defined the group was related to P. fluorescens, P. Putida, P. azotoformans and P. plecoglossicida. These strains were further characterized for the production of certain secondary metabolites involved in the fight biological against V. dahalie such as siderophores, HCN, phosphatases, the CWDE (Cell Wall Degrading enzymes) and other antimicrobial compounds. The results suggest that a combination of those metabolites could be involved in the inhibition of the formation of microsclerotia. A new strain of Pseudomonas spp. aboriginal PP30 from the tomato rhizosphere has been identified. The selected strains are excellent candidates to control V. dahliae affecting various economically important crops in Algerian agriculture.

Biography :

Email: benzinafarida@yahoo.fr