FIRST REPORT OF CURVULARIA LUNATA CAUSING LEAF SPOTS ON LOQUAT FROM PAKISTAN

The loquat (Eriobotrya japonica Lindl.) is achieving significant value in Pakistan. During the year 2014-2015, reddish brown circular spots were observed on leaves; these spots increased in size and coalesced to form oblong lesions. Samples were cut into small pieces (3 mm2), surface sterilized with sodium hypochlorite and transferred on Malt Extract Agar (MEA). These samples were incubated at 24±2°C and dark brown colonies with large stroma were observed. Septate condiophores were unbranched or simple and geniculate with dark brown scar. Brown conidia were straight to pyriform with 3-4 cells (large and curved center cell), ranging in size from 6.9 to 20.99 μm and produced apically in a sympodial manner. Morphological characterization was similar to Curvularia lunata (Ellis, 1971). PCR was used for amplification of rDNA region (White et al., 1990) and sequences of PAK34 and PAK35 was submitted to GenBank under accession Nos. KT280007 and KT280008. Both isolates were exhibiting 99% genetic homology with previously reported C. lunata isolates (KM246260, KM246262). Spore suspension (1 × 106 spore/ml) was sprayed on healthy loquat seedlings, kept in glasshouse at 30°C and plants developed lesions similar to those observed on naturally infected plants. Isolation was performed from inoculated loquat plants and morphological characterizations were similar to naturally isolated pathogens. Curvularia leaf spot diseases caused by C. lunata have been previously found on small evergreen tree. To our knowledge, this is the first report worldwide of C. lunata causing leaf spots on loquat.