Species composition of trichoderma communities in Hungarian soils used for vegetable cultivation

Abstract

Species of the genus Trichoderma are commonly found free-living fungi in soil and rootecosystems.
It is known that the rhizosphere of agricultural soils is an ideal source of
beneficial Trichoderma strains with biocontrol potential, as some of the strains showed
excellent antagonistic abilities against plant pathogenic fungi. Others are able to improve
plant growth, root in particular, promoting drought resistance in some crops.
Biodiversity of Trichoderma isolates from the rizosphere of different vegetables (pepper,
tomato, carrot, salad, spinach, pumpkin, cabbage, kohlrabi, parsley, celery, potato and
bean) in garden soil samples collected at different locations in Hungary (Szeged-Sziksóstó,
Balástya, Hódmezővásárhely, Szentes, Veszprém, Ózd) was comparatively examined
during this study. Trichoderma strains were isolated directly from the chopped roots of the
examined vegetables on dichloran - Rose Bengal medium. DNA isolation and PCR
amplification of the internal transcribed spacer (ITS1-5.8S rDNA-ITS2) region have been
used for the identification of the isolates and for the investigation of their biodiversity.
Trichoderma isolates were identified based on their ITS sequences with the aid of the
barcoding program TrichOKEY 2.0 available online at the home page of the International
Subcommission on Trichoderma and Hypocrea Taxonomy (www.isth.info).
Among the detected isolates, species known as promising biocontrol agents (T. harzianum,
T. virens, T. atroviride, T. asperellum) could be identified. Data about the biodiversity of
the genus Trichoderma in vegetable rhizosphere and surveying the in vitro antagonistic
abilities of the isolated Trichoderma strains may reveal potential biocontrol agents against
plant pathogenic fungi.
The project is co-financed by the European Union through the Hungary-Serbia IPA Crossborder
Co-operation Programme (PHANETRI, HUSRB/1002/214/068).