Identification of fungal and bacterial pathogens and control of pathogens using tomato rhizosphere antagonists in Sistan

Beydaghi, M. (2015) Identification of fungal and bacterial pathogens and control of pathogens using tomato rhizosphere antagonists in Sistan. Masters thesis, University of Zabol.

Identification of fungal and bacterial pathogens and.pdf

Download (58kB) | Preview


Tomato with the scientific name of Lycopersicum esculentum Miller belongs to the solanaceae. Tomato, after potato is the world's second economic yield.This research consider and identify fungal and bacterial pathogens of tomato in Sistan region and biological control agents antagonists isolated from the rhizosphere of the plants were completed during the growing season in 2013- 2014. To identification pathogens, several sampling of aerial and underground parts of plants were obtained from tomato fields and greenhouses. Suspected cases were transferred to the laboratory and after washing under gentle stream of water and disinfect superficial, fungal samples were plated on PDA and bacterial samples on NA culture medium. Purified Fungi and bacteria were identified at level species using the valid keys. Then, the pathogenicity test was performed. The species Fusarium solani, Fusarium compactum, Fusarium tucumaniae, Fusarium virguliforme, Fusarium psedoantophilum, Fusarium acuminatum, Fusarium heterosporum, Fusarium semitectum, Fusarium oxysporum, Rhizoctonia solani, Pythium aphanidermatum and Macrophomina phaseolina identified as wilt, plants die, charcoal rot agents and the species namely Alternaria alternate, Alternaria tomaticola, Alternaria dumosa, Alternaria mimicula, Alternaria arborescens, Alternaria tenuissima and Cladosporium cladosporiodes as agents of leaf spot and Xanthomonas campestris and Pseudomonas syringae were identified as bacterial pathogens. The species F. virguliforme, F. compactum and C. cladosporiodes were isolated from tomato for the first time in Iran and F. tucumaniae is the new specie for mycoflora of Iran. Sampling to isolation antagonists from rizospher of infected and safe plants was done. The antagonists isolated are belong to two species Trichoderma harzianum and Trichoderma virens and bacterial isolates belonging to the Bacillus subtilis. To determine the effects of antagonistic agents against fungal and bacterial pathogens dual culture on PDA were used in the laboratory. Two species namely T. harzianum and T. virens and eight isolates of Bacillus which were more effective antagonists were selected to next examinations. The experiments were conducted in a completely randomized design with three replications. Analyzing of variance was performed using SAS software and characteristics were compared using Duncan's test at the 5 percent level. Greenhouse trials results showed that the soil treated with the antagonist fungi T. harzianum and T. virens and two bacterial isolates BS1 and BS2 reduced the severity of pathogenicity caused by pathogens compared with infected witness. In soils treated with antagonistic agents observed a significant increase in plant growth factors without pathogen.

Item Type: Thesis (Masters)
Uncontrolled Keywords: Biocontrol, Inhibition, Fungistatic
Subjects: Q Science > QK Botany
Depositing User: admin admin1 admin2
Date Deposited: 26 Oct 2016 10:24
Last Modified: 26 Oct 2016 10:24

Actions (login required)

View Item View Item