Association of Alternaria alternata and Cladosporium cladosporioides with leaf spot in Cissus quadrangularis and Ficus sycomorus.
Cissus quadrangularis and Ficus sycomorus are two important wild plants in the Arabian Peninsula and other parts of the world. Leaf spot symptoms were observed on both plants in Oman, 50 km to the north-west of the Capital area, Muscat. Incidence of leaf spot disease in C. quadrangularis and F. sycomorus was 90-100% and 20-40%, respectively. Isolations were established in potato dextrose agar and the isolated fungi were identified based on sequences of the internal transcribed spacer region of the ribosomal DNA (ITS rDNA). Cladosporium cladosporioides and Alternaria alternata were found associated with the two plants. Pathogenicity test showed that A. alternata was pathogenic on C. quadrangularis while C. cladosporioides was pathogenic on F. sycomorus. This is the first report of association of A. alternata with C. quadrangularis and C. cladosporioides with F. sycomorus.