Diversity and screening for antimicrobial activity of endophytic fungi from Alstonia scholaris

Endophytic fungi of three tissues (petiole, bark and leaf) of Alstonia scholaris were assessed. A total number of 1,152 endophytic fungi were isolated from 1,002 different plant segments of seven different localities of Paschim Medinipur, West Bengal, India. The isolated fungi belong to nineteen genera, including four unidentified fungi and yeast. Colletotrichum sp. (20.39%) and Sordaria sp. (29.68%) were most commonly isolated from this plant. Hyalopus sp., Fusarium sp. and Curvularia sp. were also isolated. The colonization frequency of endophytic fungi is much higher in leaves (44.66%) in comparison to petioles (32.16%) and barks (23.17%). The study provided evidence for tissue specificity of endophytic fungi. The endophytic fungal species diversity was higher in plant segments collected from Gopegarh and Khoirullahchak, while diversity was the lowest in Rice mill area. Screenings of antimicrobial activity of these isolated endophytic fungi were done. Eight endophytic fungi showed antimicrobial activity. Among them Curvularia sp., Aspergillus sp. and one unidentified fungus showed maximum activity against test pathogens.