Isolation and identification of Esteya vermicola and its potential for controlling pinewood nematode

Abstract

AbstractPine wilt disease is a devastating forest disease worldwide caused by the pinewood nematode (PWN; Bursaphelenchus xylophilus). Esteya vermicola is widely recognized as a promising bio‐control agent effective against PWN. During a survey of associated microorganisms of Pinus yunnanensis in Southwest China, a novel isolate of E. vermicola was obtained. This isolate produced two types of conidia. One type of conidia was hyaline, unicellular, bacilloid, and non‐adhesive. The second type of conidia is solitary, hyaline, unicellular asymmetric elliptic or lunate, concave inward, ending slightly apiculate, adhesive on the concave surface, and contained an ovoid endospore‐like structure. Only the lunate conidia showed infection activity against PWN. This novel isolate produced a high proportion of infective lunate conidia and exhibited high adhesion and infection activity against PWN by adhering to the nematode within 48 h and killing 74.5% of the tested PWN individuals within 4 days. Given that the isolate was obtained from P. yunnanensis, it may be well adapted to the endogenous environment of pine trees. The isolate shows potential as a bio‐control agent against a plant‐parasitic nematode in the field.