Vegetative Growth and Molecular Identification of <i>Fusarium equiseti</i> Isolated from Wilt Disease of <i>Centella asiatica</i> L. in Bangladesh

Abstract

Centella asiatica (L.) is commonly known as Thankuni plant and has ethnobotanical importance in Bangladesh. Present experiment was conceded to investigate the wilt disease of C . asiatica , vegetative growth and molecular characterization of pathogenic fungi. Pathogenic fungus, Fusarium equiseti was identified as a causal agent of wilt disease in C . asiatica . The effect of culture media on the mycelial growth of F. equiseti showed the highest (89.25 mm) on potato dextrose agar (PDA) medium followed by carrot agar (CA) medium and the lowest growth (40.25 mm) was measured in HA medium. The optimal temperature and pH for mycelial growth of F. equiseti were 30&deg;C and 7, respectively. The genetic variation of the selected species of fungi, the internal transcribed spacer (ITS) region was amplified using ITS4 and ITS5 primers an d sequenced. The PCR product of the ITS region of F. equiseti was 535 bp. Phylogenetic tree of thirty-seven strains of Fusarium sp. based on the nucleotide sequences of the ITS region using the neighbor-joining method with 1000 bootstrapping indicated that 98% - 100% identity with MN886590.1 JUF0046 ( F. equiseti ). ITS sequences are generally constant, or show little variation within species, but vary between species in a genus. The ITS region is relatively short and can be easily amplified by PCR using universal single primer pairs. Genetic distance exhibited high level of similarity with identical ITS sequences. To date, no published research articles are found on the molecular identification of F. equiseti , the causal agent of fusarium wilt disease of C . asiatica in Bangladesh .