Isolation and characterisation of Aspergillus awamori BS05, a root-knot-nematode-trapping fungus

Abstract

Nematode-trapping fungi are important biocontrol agents against parasitic nematodes through adhesive or mechanical hyphal traps. Aspergillus awamori, a root-knot-nematode-trapping fungus from tomato rhizosphere soil, was identified based on morphology and molecular characteristics of internal transcribed spacer DNA sequence. Conidial heads were white to black brown, loosely globose, and 72–127 μm in diameter. Conidiophores usually arose from the foot cell of basal mycelium, straight, and 960–1730 × 10.2–13.4 μm, hyaline to pale brown, not constricted below the vesicles; vesicles hemispherical to elongate, 43–56 μm in diameter, black brown, fertile over the upper half to two-thirds. Aspergilla were biseriate, and metulae were variable, 12–26 × 3.8–4.7 μm; phialides were 8.2–9.4 × 2.5–3 μm. Conidia were globose or subglobose, 3.6–4.8 μm in diameter, rough, grey brown and parallel in chains. A. awamori BS05 showed 44.9% control efficacy against Meloidogyne incogtina in pot experiments which suggests it as a potential biocontrol agent against Meloidogyne. This is the first report on A. awamori as nematode-trapping fungus.

Keywords:

• nematode-trapping fungi
• Aspergillus awamori
• Meloidogyne incogtina
• biocontrol

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 31260423].