First report of wilt disease caused by Fusarium oxysporum spp on fishtail palm in India

Abstract

The identification and characterization of Fusarium oxysporum sp isolated from vascular tissues of root of Fishtail (Caryota urense) palm from Bastar district of Chhattisgarh state. The fungal species produced hyaline mycelium and produced spores within the host tissues as well as in the culture. Micro conidia were most abundantly produced and observed as small, elliptical or curved unicellular or with 1-2 septa and measured 5-15 × 2-4 um. Macro conidia were produced in small cushion of somatic mycelium measured long, curved septa 3-4 and size 15-25 × 3-5 um. Chlymydospores was also formed in the host as well as in old culture. They developed from any cell of the fungus. The fungal growth on plate was filamentous and whitish in color. The results of molecular analysis revealed that the ∼500 bp rDNA of Fusarium oxysporum sp from fishtail shares 100% sequence identity with that of known Fusarium oxysporum sp isolates. The identified species proved its pathogenicity characterized on aerial part of the plants as symptoms were observed in any one leaf blade of plant dried initially characteristically as yellow to brown colored, drying of leaves started from margin. Infection was also observed below the ground level as brown to dark black colored vessels.