Occurrence of races of Pyrenophora tritici-repentis (Died.) Drechs., causal agent of tan spot of wheat in Argentina

M.V. MORENO; G.L. SALERNO; W.J. ROGERS; A.E. PERELLÓ

Mar del Plata, Prov. de Buenos Aires

Congreso; VI CLAM. Congreso Latinoamericano de Micología; 2008

Sociedad Latinomaricana de Micología

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;} p.MsoFooter, li.MsoFooter, div.MsoFooter {margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; tab-stops:center 212.6pt right 425.2pt; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;} @page Section1 {size:595.3pt 841.9pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Tan spot is characterized by the development of tan necrosis (Nec) and extensive chlorosis (Cl) on the leaves. Based on these symptoms, fungal isolates have been grouped so far eight races. Isolates of the pathogen were obtained from different regions and cultivars of Argentina. They were tested for their race structure by inoculation on wheat differential set. H0019 was determined as race 1 (Nec in Glenlea-Katepwa and Cl in 6B365). CH007, G0332, O0015 and P027 were grouped in race 2, (Nec in Glenlea-Katepwa). H0012 was determined as race 3, (Cl in 6B365). CH006, G033, G0311 and V0212 were identified as race 4, they did not produce symptoms. H0114 was identified as race 5, (Cl in 6B365-Katepwa). G0315 was determined as race 6, (Cl in Katepwa- 6B662-6B365). G0323, G0334, H001 and P0313 were grouped as race 8, (Nec in Glenlea, NecCl in Katepwa and Cl in 6B365-6B662). This is the first report about the presence of races 2, 3, 4, 5, 6, and 8 in Argentina. More isolates are under genetic and race structure investigation.