INVESTIGADORES
DIAZ RICCI Juan Carlos
artículos
Título:
Induction of a defense response in strawberry mediated by an avirulent strain of Colletotrichum
Autor/es:
SALAZAR, SERGIO MIGUEL; CASTAGNARO, ATILIO PEDRO; ARIAS, MARTA EUGENIA; CHALFOUN, NADIA REGINA; TONELLO, URSULA; DIAZ RICCI, JUAN CARLOS
Revista:
EUROPEAN JOURNAL OF PLANT PATHOLOGY
Editorial:
European Journal of Plant Pathology
Referencias:
Lugar: Dordrecht, The Netherland; Año: 2007 vol. 117 p. 109 - 122
ISSN:
0929-1873
Resumen:
In the strawberry crop area of Tucumán (north-west Argentina) the three species of  Colletotrichum causing the anthracnose disease (e.g. C. acutatum, C. fragariae and C. gloeosporioides) were detected. Among all isolates characterized, one of them identified as C. actutatum (M11) and another as C. fragariae (F7) were selected due to their conspicuous interaction with the strawberry cultivar Pájaro. Whereas the isolate M11 produced a strong compatible interaction in the cv. Pájaro with clear disease symptoms (DSR= 5.0), the isolate F7 brought about a typical incompatible interaction (DSR= 1.0). When plants of the cv. Pájaro were inoculated with F7 prior to the inoculation with M11, the former avirulent strain prevented the growth of the latter virulent pathogen. Experimental evidence indicated that the time elapsed between the first inoculation with avirulent pathogen and the second inoculation with the virulent one was crucial to inhibit the growth the latter. The growth of F7 on the plant without provoking damage and the fact that there was no in vitro antagonistic effect between the pathogens, suggested that the avirulent strain triggers on the plant a defensive response against M11. The defense response was further confirmed by the detection of an early oxidative burst occurring within four hours after the first inoculation and by the observation of anatomical changes associated to defense mechanisms that lasted 50 days after the inoculation with F7. Results obtained support the hypothesis that the plant resistance against the virulent strain M11 is elicited by one or more diffusible(s) compound(s) produced by the avirulent strain F7.