Comparison of the effects of Fusarium solani filtrates in vitro and in vivo on the morphological characteristics and peroxidase ativity in pea cultivars with different susceptibility (2011)

Intact plants and in vitro cultures of four pea (Pisum sativum) cultivars (Adept, Herold, Komet, Menhir) that vary in their degree of susceptibility/resistance to Fusarium solani were inoculated with this pathogen or treated with its culture filtrates to compare their reaction patterns at the phenotypic, histological and biochemical level. Changes in activity of three peroxidase forms, cytosolic, membrane- and ion-bound, and in peroxidase isozymes were studied in detail. In addition, the length and weight of roots of regenerating plantlets in explant cultures as well as symptom expression in intact plants were assessed. In planta, screening of the four pea cultivars revealed the highest degree of resistance in cv. Adept, and the highest level of susceptibility in cv. Menhir both to F. solani and its metabolites. Regarding in vitro cultures, the microfiltrated filtrates had stronger inhibitive effect than the autoclaved ones. In terms of peroxidase activity, the only significant difference among cultivars was found in its ionic form, for the most resistant cv. Adept versus the most sensitive cv. Menhir. Minor changes in activity of cytosolic peroxidase were noted in planta and in vitro, while the membrane- and ion-bound peroxidase significantly decreased in explants. The aim of our study was to compare reaction of pea plants and explants and to verify whether the application of fungal filtrates is able to mimic the F. solani pathogenesis. Several responses of explants to filtrates were found to be analogous to the plant reaction to pathogen infection both at morphological and physiological levels. These can be utilized in an early in vitro screening for plant tissue resistance to F. solani.

Journal of Plant Pathology (2011), 93 (1), 19–30. ISSN 1439-0434  [Fulltext PDF]