Development of chlamydospores in Alternaria alternata

Abstract

During the study of a leaf spot disease of sunflower (Helianthus annuus) caused by Alternaria alternata, the fungus was found to produce chlamydospores in hyphal cells of mycelium submerged in agar cultures. Chlamydospores, formed in intercalary or terminal chains within 5 months at 4 C, were globose to ellipsoid, dictyosporous, smooth or verrucose, pale brown, and averaged 14.3 × 11.5 μm. Conidia produced in cultures at 4 C were finally converted to chlamydospores as well.

Key Words:

• Alternaria alternata
• chlamydospores
• sunflower