Production of Purpureocillium lilacinum and Pochonia chlamydosporia by Submerged Liquid Fermentation and Bioactivity against Tetranychus urticae and Heterodera glycines through Seed Inoculation

Abstract

Pochoniachlamydosporia and Purpureocilliumlilacinum are fungal bioagents used for the sustainable management of plant parasitic nematodes. However, their production through submerged liquid fermentation and their use in seed treatment have been underexplored. Therefore, our goal was to assess the effect of different liquid media on the growth of 40 isolates of P. lilacinum and two of P. chlamydosporia. The most promising isolates tested were assessed for plant growth promotion and the control of the two-spotted spider mite (Tetranychus urticae) and the soybean cyst nematode (Heterodera glycines). Most isolates produced > 108 blastospores mL−1 and some isolates produced more than 104 microsclerotia mL−1. Microsclerotia of selected isolates were used to inoculate common bean (Phaseolus vulgaris L.) seeds in greenhouse trials. All fungal isolates reduced the T. urticae fecundity in inoculated plants through seed treatment, while P. chlamydosporia ESALQ5406 and P. lilacinum ESALQ2593 decreased cyst nematode population. Purpureocillium lilacinum was more frequently detected in soil, whereas P. chlamydosporia colonized all plant parts. Pochonia chlamydosporia ESALQ5406 improved the root development of bean plants. These findings demonstrate the possibility of producing submerged propagules of P. chlamydosporia and P. lilacinum by liquid culture, and greenhouse trials support the applicability of fungal microsclerotia in seed treatment to control P. vulgaris pests.

Toxicity of fungal‐derived volatile organic compounds against root‐knot nematodes

“…In the present study, we found that four pure VOCs induced both direct toxicity and adverse chemotaxis responses to M. incognita J2s, while these effects were compound and dose dependent. That VOCs can induce chemotaxis or repulsive effects in nematodes has been tested in a variety of systems 50–52 . Thus, as we showed that RKNs, such as M. incognita , suffered fitness consequences when in contact with these pure compounds, RKNs might try to avoid EPF via the observed repulsive behavior.…”

“…That VOCs can induce chemotaxis or repulsive effects in nematodes has been tested in a variety of systems. [50][51][52] Thus, as we showed that RKNs, such as M. incognita, suffered fitness consequences when in contact with these pure compounds, RKNs might try to avoid EPF via the observed repulsive behavior. Interestingly, we also found that direct contact with pure VOCs inhibited egg hatching of RKNs, although only at high concentrations (100 mg/L).…”

“…Therefore, in addition to actively killing nematodes, 48 soil fungi, and in particular EPF, could reduce plant‐pathogenic nematode populations indirectly by producing VOCs. Therefore, Talaromyces sp ., Trichoderma sp ., and P. lilacinum isolated in this study could be exploited as biological agents for controlling plant parasitic nematodes, in addition to using these fungi for their insecticidal activity 49,50 …”

Development of a Seed Treatment with Pochonia chlamydosporia for Biocontrol Application

“…In general, drying blastospores is still a challenge [13], especially for large-scale processes and thus for commercially suitable products. In some studies, blastospores were dried in solid materials such as diatomaceous earth [45,46]. The viability of B. bassiana blastospores after air-drying and spray-drying was greater than 80% [45].…”

Pre-treatment with Dazomet enhances the biocontrol efficacy of purpureocillium lilacinum to Meloidogyne incognita

“…Purpureocillium lilacinum (syn. Paecilomyces lilacinus ) is a promising nematophagous fungus which remarkably suppresses various plant nematodes by parasitizing eggs and females, producing cell wall degrading enzymes and nematicidal metabolites [ 18 – 22 ]. However, in seriously infested soil, application of the biocontrol agents sometimes was unsuccessful [ 23 – 25 ].…”