Abstract

Kumela Regasa Tiki

Kei-apple (Dovyalis caffra L) is an indigenous evergreen spiny or shrub tree of southern Africa. It is currently grown in the arid and semi-arid regions of the world. The tree has a potential benefit as a critical component of the rural-urban landscape in Ethiopia. However, in 2021 leaf spots disease was observed on seedlings from different nurseries sites in Ethiopia. Initial symptoms included a small spot on the seedling leaves that enlarged and coalesced to give rise to larger irregular spots. Samples showing leaf spots were collected and isolated onto Potato Dextrose Agar (PDA) to identify the causal agent. Based on these morphological features, the fungus was identified as Pestaiopisis palmarum. Fungal colonies developed on PDA are copious white aerial mycelium covering the entire Petri dish area after 7 to 10 days, have a smooth edge, and thin mycelium. Conidia shape is fusiform to ellipsoid, mainly straight and septate. To confirm pathogenicity, spraying conidial suspension of the pathogen (105 spores / mL) was used. After 7 days, leaves developed symptoms that were similar to those seen in the field. On leaves sprayed with distilled water which is used as control, no symptoms were seen. Pestaiopisis palmarum was re-isolated from the inoculated and reconfirmed by morphological characteristics. This is the first report of Pestalotiopsis spp causing leaf spot disease of Dovyalis caffra L. in Ethiopia. This information is significant to further study and develop management strategies of seedling loss of Dovyalis caffra L in Ethiopia.