caa a22 4500 378901958 CHVBK 20180305123520.0 cr unu---uuuuu 161128e20040701xx s 000 0 eng 10.2298/hel0440171p doi (NATIONALLICENCE)gruyter-10.2298/hel0440171p INFECTION COURTS AND LENGTH OF SUSCEPTIBLE PERIOD RELATED TO SUNFLOWER HEAD ROT (Sclerotinia sclerotiorum) RESISTANCE [Elektronische Daten] LUGARES DE INFECCIÓN Y DURACIÓN DEL PERÍODO DE SENSIBILIDAD, RELACIONADO CON LA RESISTENCIA DE LA PODREDUMBRE HÚMEDA DEL CAPÍTULO DE GIRASOL (Sclerotinia sclerotiorum / LIEUX D'INFECTION ET LONGUEUR DE PÉRIODE DE SENSIBILITÉ CONCERNANT LA RÉSISTANCE DE POURRITURE DE CAPITULE DE TOURNESOL (Sclerotinia sclerotiorum) / [M.V. Pedraza, V.R. Pereyra, A.R. Escande] Sunflower head rot (SHR) (Sclerotinia sclerotiorum (Lib.) de Bary) is one of the major diseases affecting this crop worldwide. In spite of reports of different levels of susceptibility among sunflower genotypes, there is no evidence of complete resistance in any commercial hybrid. The aim of this work was to evaluate the number of infection courts and the length of the susceptible period in two genotypes with contrasting but stable SHR susceptibility. Repeated experiments during three years in the field included the sunflower hybrids Paraíso-20, moderately resistant, and Rancul, susceptible. Plants were inoculated with ascospores by spray application. Only one or two infection courts were found in each infected sunflower head and this feature did not distinguish cultivar susceptibility. Differences between cultivars were detected considering the length of the susceptible period based on disease incidence higher than zero (LSP) or higher than 10% (LSP10) in two out of three years. LSP was longer in Rancul (28 days) than in Paraíso-20 (17 days). Also LSP10 was longer in Rancul (22 days) than in Paraíso-20 (9 days). The suitability of these two features as components of partial resistance is discussed This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Helianthus annuus L nationallicence infection courts nationallicence partial resistance nationallicence Sclerotiniasclerotiorum nationallicence sunflower head rot nationallicence susceptible period nationallicence Pedraza M.V. Unidad Integrada Balcarce INTA-Universidad de Mar del Plata, CC 276, Balcarce (7620), Argentina aut Pereyra V.R. Unidad Integrada Balcarce INTA-Universidad de Mar del Plata, CC 276, Balcarce (7620), Argentina aut Escande A.R. Unidad Integrada Balcarce INTA-Universidad de Mar del Plata, CC 276, Balcarce (7620), Argentina aut HELIA De Gruyter 27/40(2004-07-01), 171-182 1018-1806 27:40<171 2004 27 helia https://doi.org/10.2298/hel0440171p text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.2298/hel0440171p text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Pedraza M.V. Unidad Integrada Balcarce INTA-Universidad de Mar del Plata, CC 276, Balcarce (7620), Argentina aut NATIONALLICENCE 700 1- Pereyra V.R. Unidad Integrada Balcarce INTA-Universidad de Mar del Plata, CC 276, Balcarce (7620), Argentina aut NATIONALLICENCE 700 1- Escande A.R. Unidad Integrada Balcarce INTA-Universidad de Mar del Plata, CC 276, Balcarce (7620), Argentina aut NATIONALLICENCE 773 0- HELIA De Gruyter 27/40(2004-07-01), 171-182 1018-1806 27:40<171 2004 27 helia CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter