TY  - PRO
AU  - Di Zinno,T.
AU  - Duveiller,E.|Dubin,H.J.|Reeves,J.|McNab,A.
AU  - Longree,H.
AU  - Maraite,H.
ED  - Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT), Mexico DF (Mexico)
TI  - Diversity of Pyrenophora tritici-repentis isolates from warm wheat growing areas:  Pathogenicity, toxin production, and RAPD analysis
SN  - 970-648-001-3
U1  - 633.1194 
PY  - 1998///
CY  - Mexico, DF (Mexico)
PB  - CIMMYT|UCL|BADC
KW  - Inoculation methods
KW  - Pathogens
KW  - Plant diseases
KW  - AGROVOC
KW  - Pyrenophora
KW  - Toxins
KW  - Triticum
KW  - CIMMYT
N2  - The diversity of Pyrenophora tritici-repentis isolates collected from warm wheat growing areas around the world was studied. Four cultivars (Ciano, Hartog, Vicam, and BH1146) at the three-leaf stage were inoculated with a conidial suspension under controlled conditions. Vicam appeared resistant to all P. tritici-repentis isolates, while Ciano, BH1146, and Hartog showed varying susceptibility levels. Interactions were observed between cultivars and isolates, especially between Hartog and Ciano and the most aggressive isolates. Using a single conidium inoculation method on detached leaves, all P. tritici- repentis isolates failed to produce symptoms on Vicam, whereas tan necrosis was induced by some isolates on Ciano, Hartog, and BH1146. Strains and cultivars were differentiated by induction and expression of necrosis, respectively. Strains that induced lesions were observed to produce necrosis-inducing toxins on all susceptible cultivars; however, ND/VG9144//KAL/BB/3/YA was the exception. It failed to develop symptoms when infiltrated by the toxin, even though it is susceptible to tan spot under both field and controlled conditions. Preliminary results from random amplified polymorphic DNA (RAPD) analyses indicated the presence of polymorphism between strains, but no correlation could be established between these differences and geographic origin, pathogenicity, and toxin production
ER  -