First Report of Lavender Wilt Caused by Fusarium sporotrichioides in Croatia

In May 2011, samples of lavender plants (Lavandula × intermedia) showing wilt symptoms were collected from two commercial plantings in Slavonia County. Disease was observed on 20 to 30% of the plants. Symptoms of the disease consisted of chlorosis, stunting, wilting, and death. Vascular tissue of stems and roots exhibited brown discoloration. Isolations of the pathogen were made from the discolored tissues on potato dextrose agar (PDA). Colonies were initially white, but with age became red, and red pigments were produced in agar. Microconidia were pear shaped, oval, and fusoid, and ranged from 4.5 to 14.0 × 2.8 to 4.7 μm. Macroconidia were curved, mostly three septate, and ranged from 21.8 to 24.3 × 2.9 to 3.9 μm. Morphology of colonies and conidia matched the description of Fusarium sporotrichioides Sherb. (1). Identity of the fungus was confirmed by examining a portion of the EF1-α gene using the degenerated primers EF1 and EF2 (2). BLAST searches of the obtained sequences showed a 100% homology with s...