Evaluation of the protection range of a defense elicitor obtained from an avirulent strain of Colletotrichum

CHALFOUN NADIA REGINA; SALAZAR SERGIO MIGUEL; LEMME MARÍA CECILIA; CASTAGNARO ATILIO PEDRO; DÍAZ RICCI JUAN CARLOS

Tafí Del Valle, Tucumán. Argentina

Jornada; XXIII Jornadas Científicas de la Asociación de Biología de Tucumán; 2006

Asociación de Biología de Tucumán

The anthracnose caused by fungi of the genera Colletotrichum, is the disease that impact more severely strawberry crop. In Tucumaán the three pathogenic species involved were detected (C. fragariae, C. glocosporioides and C. acutatum). Phytopatological experiments revealed that different strawberry cultivars responded differentially when challenged with a particular pathovar and also that different pathovars affected with different degree of severity a particular cultivar. We have reported earlier that plants treated with sterile supernatant of a liquid culture of an avirulent isolate of C.fragariae (M23) induced a defense response in the cv. Pájaro. We have investigated whether the eliciting activity corresponds to a specific (race specific) or general (non-race specific) elicitor. We have carried out protection experiments with different virulent local isolates of C. acutatum (e.g. M11, MP3 and LCF1-05) and different strawberry cultivars (e.g. cvs Pájaro, Camarosa, Milsei Tudla and Chandler ) using the elicitor fraction coming from the isolate M23 of C. fragariae. Results show that after the treatment with the elicitor, pants of the cvs. Pájaro and Camarosa did not present disease symptoms (DSR=1) 40 dpi, whereas those of cvs Milsei Tudla and Chandler got barely affected (DSR=2) 30 dpi.These outcomes let us conclude that the eliciting activity used corresponds to a general (non-race specific) elicitor.