title: Identification of potential marker genes for Trichoderma harzianum strains with high antagonistic potential against Rhizoctonia solani by a rapid subtraction hybridization approach.
abstract: A rapid subtraction hybridization approach was used to isolate genes differentially expressed during mycelial contact between Trichoderma harzianum (Hypocrea lixii) and Rhizoctonia solani, and could serve as marker genes for selection of superior biocontrol strains. Putatively positive clones were evaluated by transcription analysis during mycelial contact with R. solani versus growth on glucose, and for their differential transcription between two strains with either strong or poor biocontrol capability before, at, and after contact with R. solani. Besides four clones, which had similarity to putative but as yet uncharacterized proteins, they comprised ribosomal proteins, proteins involved in transcriptional switch and regulation, amino acid and energy catabolism, multidrug resistance, and degradation of proteins and glucans. Transcription of three clones was evaluated in five T. harzianum strains under confrontation conditions with R. solani. Two clones-acetyl-xylane esterase AXE1 and endoglucanase Cel61b-showed significant upregulation during in vivo confrontation of a T. harzianum strain that successively demonstrated a very high antagonistic capability towards R. solani, while expression was progressively lower in a series of T. harzianum strains with intermediate to poor antagonistic activity. These clones are promising candidates for use as markers in the screening of improved T. harzianum biocontrol strains.
authors.affiliation: Department of Plant Protection, Center for Biotechnology Development and Biodiversity Research, University of Sassari, Via E. De Nicola 9, 07100, Sassari, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Scherm
authors.forename: Monika
authors.initials: M
authors.lastname: Schmoll
authors.forename: Virgilio
authors.initials: V
authors.lastname: Balmas
authors.forename: Christian P
authors.initials: CP
authors.lastname: Kubicek
authors.forename: Quirico
authors.initials: Q
authors.lastname: Migheli
mesh_terms: D005800:Genes, Fungal; D005819:Genetic Markers; D003368:Gossypium / Q000235:genetics / Q000382:microbiology; D025282:Mycelium / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D012232:Rhizoctonia / Q000254:growth & development* / Q000472:pathogenicity; D014242:Trichoderma / Q000502:physiology*
chemical_list: D005819:Genetic Markers