Screening of wild Helianthus for novel resistance sources.

MILADINOVIC; D., DEDIC;B., CANTAMUTTO M., POVERENE M, IMEROVSKI I., DIMITRIJEVIC; A., JOCIC; S.

Alnarp

Conferencia; EUCARPIA Meeting 2013; 2013

Swedish University of Agricultural Sciences

Broomrape (Orobanche cumana Wallr.) is the most serious constrain for sunfl ower (Helianthus annuus L.) production in Southern and Eastern Europe. In these areas it causes considerable yield losses and reduces sunfl ower seed quality. Genetic resistance had proved to be the most effi cient method for suppressing severe broomrape attacks in the fi eld, however selection pressure resulted in occurrence of new, and more aggressive races of the parasite. Broomrape is absent in the centre of origin of the genus Helianthus and in the sunfl ower crop areas of Latin America. In Argentina, one of the fi ve main producer countries, the parasite is also absent in the exotic populations of H. annuus and H. petiolaris naturally developed in the sunfl ower crop area (Cantamutto et al. 2010). Both natural and broad genetic resistance in Argentina sunfl owers could be potentially responsible for broomrape absence in Argentina (Miladinovic et al. 2012). In order to check this hypothesis and find potential novel resistance sources we have screened wild H. annuus (N=4) and H. petiolaris accessions (N=4)from Argentina for their resistance to broomrape, as described by Terzic et al. (2010). The ANOVA showed high signifi cant differences between species. The tested accessions of H. annuus were susceptible and had 4.3 ± 3.3 broomrape tassels per plant. All the accessions of H. petiolaris tested were resistant to broomrape as no broomrape tassels were observed. Similar results were obtained by Terzic et al. (2010) who tested H. petiolaris accessions from the USA. This wild Helianthus species could be a valuable source of broomrape resistance genes that could be incorporated into cultivated sunfl ower by interspecific crossing.