VARIABILITY OF Phomopsis POPULATIONS IN SUNFLOWER (Helianthus annuus L.) / VARIABILIDAD DE LAS POBLACIONES DE Phomopsis EN EL GIRASOL (Helianthus annuus L.) / VARIABILITÉ DES POPULATIONS DE Phomopsis CHEZ LE TOURNESOL (Helianthus annuus L.)

Abstract

SUMMARY Various reports state that the sunflower disease, primarily caused by Diaporthe/Phomopsis helianthi Munt.-Cvet. et al., has a wide geographic distribution in Europe, USA, Argentina and Australia. Various Phomopsis isolates obtained during this investigation of the sunflower disease differed in conidial type (α, β, α and β). Phomopsis helianthi was the only isolate producing exclusively β-conidia and perithecia on debris (Diaporthe helianthi). The other Phomopsis isolates were saprobes on sunflower plants.