Mycoparasitism studies of Trichoderma harzianum strains against Rhizoctonia solani: evaluation of coiling and hydrolytic enzyme production.
The genus Trichoderma is a potential biocontrol agent against several phytopathogenic fungi. One parameter for its successful use is an efficient coiling process followed by a substantial production of hydrolytic enzymes. The interaction between fifteen isolates of Trichoderma harzianum and the soil-borne plant pathogen, Rhizoctonia solani, was studied by light microscopy and transmission electron microscopy (TEM). Macroscopic observations of fungal growth in dual cultures revealed that growth inhibition of the pathogen occurred soon after contact with the antagonist. All T. harzianum isolates tested exhibited coiling around the hyphae of R. solani. The strains ALL23, ALL40, ALL41, ALL43 and ALL49 did not differ in coiling frequency and gave equal coiling performances. No correlation between coiling frequency and the production of cell wall-degrading chitinases, N-acetyl-beta-D-glucosaminidase and beta-1,3-glucanases, was found.
Almeida
Fausto Bruno dos Reis
FB
Laboratório de Enzimologia, Universidade Federal de Goiás (ICB), 74001-970, Goiânia, GO, Brazil.
Cerqueira
Fernanda Menezes
FM
Silva
Roberto do Nascimento
Rdo N
Ulhoa
Cirano José
CJ
Lima
Adilson Lopes
AL
D001709:Biotechnology / Q000379:methods*; D002473:Cell Wall / Q000378:metabolism; D002688:Chitinases / Q000737:chemistry / Q000378:metabolism; D004798:Enzymes / Q000737:chemistry; D006868:Hydrolysis; D046529:Microscopy, Electron, Transmission; D008954:Models, Biological; D010572:Pest Control, Biological; D010935:Plant Diseases; D010936:Plant Extracts / Q000378:metabolism; D012232:Rhizoctonia / Q000378:metabolism*; D014242:Trichoderma / Q000378:metabolism*
D004798:Enzymes; D010936:Plant Extracts; D002688:Chitinases