Phytotoxic potential of endophytic fungi from leaves of Serjania lethalis on wheat (Triticum aestivum L.) and weeds (Euphorbia heterophylla and Megathyrsus maximus)

We evaluated the phytotoxicity of two endophytic fungi Alternaria sp. and Diaporthe sp. from leaves of Serjania lethalis on wheat (Triticum aestivum L.) and weeds (Euphorbia heterophylla and Megathyrsus maximus). The mycelial and culture medium extracts of the two fungal species were obtained by extraction of the mycelium with ethanol and the culture medium with ethyl acetate, respectively. The phytotoxicity of extracts of each fungus was tested on the growth of wheat coleoptiles (Triticum aestivum L.). The ethyl acetate extract of the culture filtrate of Alternaria sp. and the ethanolic extract of Diaporthe sp. mycelia were most active. Hence they were further studied, to determine their effects on seed germination and seedling growth of Euphorbia heterophylla L. (wild poinsettia) and Megathyrsus maximus (colony grass). The results showed that the culture extract of Alternaria sp. was phytotoxic to the germination and growth of E. heterophylla seedlings. While the mycelial extracts of Diaporthe sp. decreased the seed germination of M. maximus and the growth of E. heterophylla seedlings roots.