tailieunhanh - Molecular characterization of potent biocontrol isolates of Trichoderma asperellum and Pseudomonas fluorescens from tomato rhizosphere

The potent native bioagents isolated from tomato rhizosphere have high antagonistic potential against Phytophthora infestans. Molecular characterization of fungal isolates (T-11 and T-14) was performed by using Internal Transcribed Spacer (ITS) region of 18S rRNA sequence. The sequence analyses of two isolates (MK928414 and MK928417), showed 100% similarity with Trichoderma asperellum during BLAST analysis. The phylogeny tree constructed by using sequence analysis showed the formation of cluster along with T. asperellum and both the isolates were identified as T. asperellum. The rhizospheric potential bacterial isolates (Pf-2 and Pf-3) were isolated and characterized at molecular level. Bacterial isolates were identified as Pseudomonas fluorescens by using 16S-23S rRNA intervening sequence specific ITS1 and ITS2 primers. The sequence analyses of two isolates showed similarity with P. fluorescens during BLAST analysis and received the NCBI GenBank accession number of MN783298 and MN783297 for Pf-2 and Pf-3 isolates respectively. These isolates were further confirmed by phenotypic characteristics. It is inferred from the present study, that taxonomical knowledge on bioagents is important for accurate identification and molecular characterization of potential biocontrol species. This is to undeniably avoid potential risk of introducing an unknown bacterial and fungal species into the rhizosphere of a given ecosystem. | Molecular characterization of potent biocontrol isolates of Trichoderma asperellum and Pseudomonas fluorescens from tomato rhizosphere