Fungal populations on sunflower (Helianthus annuus) anthosphere and their relation to susceptibility or tolerance to Sclerotinia sclerotiorum attack.

RODRIGUEZ, MARIA ALEJANDRA; VENEDIKIAN, NADIA; GODEAS, ALICIA

MYCOPATHOLOGIA

Kluwer Academic Publisher

Lugar: Dordrecht; Año: 2001 vol. 150 p. 143 - 150

0301-486X

Analysis of the fungal flora from different floret parts of various sunflower (Helianthus annuus) varieties showed that there are differences in both fungal species and frequency, depending on whether the sunflower variety is susceptible (SV) or tolerant (TV) to attack of the flower heads by the ascomycete pathogen Sclerotinia sclerotiorum. The sunflower varieties analysed were SV: HA 300 and Z20028 and TV: HA 302, Z AV 8410 and Z 30629. The isolates showed different "in vitro" behavior as control agents. The most common types of interaction with Sclerotinia sclerotiorum were D2 and D2+ (hyphal contact) for isolates from SV and TV, while some of the isolates from TV displayed antibiosis. The microorganisms that colonize TV florets play a part in an indirect mechanism that protect flowers from ascospores germination and pathogen growth.