The pathogenicity of entomopathogenic fungus Acremonium hansfordii to two-spotted spider mite, Tetranychus urticae and predatory mite Neoseiulus barkeri

Abstract

The two-spotted spider mite, Tetranychus urticae, is an important mite pest worldwide. It often leads to reduced crop yields or poor marketability of the produce and has already developed resistance to many acaricides. In this study, the pathogenicity of the entomopathogenic fungus (EPF), Acremonium hansfordii, to T. urticae and its side effects on the predatory mite Neoseiulus barkeri were compared. The toxicity of A. hansfordii was evaluated on T. urticae at 1.0×104, 1.0×106, 1.0×108 conidia/mL concentrations and predatory mite N. barkeri at 1.0×108 conidia/mL under experimental conditions at 25±1°C, 75±5% RH and 16L: 8D photoperiod. The effects of EPF on the development of the F0 and F1 generation of predatory mites were also assessed at 1.0×108 conidia/mL concentration. The results showed that the corrected mortality of T. urticae at three tested concentrations were 36.67%, 53.67% and 66.33% within 11d, and the median lethal time were 14.39 d, 9.84d and 7.99d, respectively. The corrected mortality of N. barkeri was only 3.9% after 11d at 1×108 conidia/mL concentration. Some hyphae of A. hansfordii were detected on the surface of treated T. urticae but not on N. barkeri body after 7d. After N. barkeri females were treated with 1.0×108 conidia/mL, the preoviposition period of the F0 generation was prolonged 1.56 times and the other life history parameters have no significant differences; similar patterns were also shown in the F1 generation. A. hansfordii showed strong pathogenicity against T. urticae but did not significantly adversely influence N. barkeri. Therefore, the combination of A. hansfordii and N. barkeri has the potential to be used for the control of T. urticae in the future.

Acremonium capsici and A. guizhouense, two new members of Acremonium (Hypocreales, Sordariomycetes) isolated from the rhizosphere soil of Capsicum annuum

“…Members of the genus Acremonium are geographically widespread and ecologically diverse, and seem to colonize all types of substrates, including endophytes, epiphytes, saprophytes, human and plant pathogens, lichens, insects, or arthropods taxa (Yang et al 2019). In addition, Acremonium species have various functions, such as biological control (Shang et al 2018), enhancing drought tolerance of grasses, and promoting nectar production of beans (Jaber and Vidal 2009), as well as improving plant resistance to plant pathogens (Kasselaki et al 2006). In the present study, all the isolates were obtained from the rhizosphere soils of Capsicum annuum.…”

The influence of Ahy1 strain of Acremonium hansfodii on functional response of Neoseiulus barkeri to Tetranychus urticae

“…In our previous study, we had found that the entomopathogenic fungus A. hansfodii could infect the prey effectively while it had less pathogenicity to the predatory mite (Shang et al 2018), which is considered as a good basis for evaluating the compatibility of the two. In order to compare the efficacies of N. barkeri as biocontrol agents of T. urticae, the consumption rates and functional responses of fungi-infected N. barkeri when feeding on different stages of T. urticae or N. barkeri feeding on different stages of T. urticae infected by the fungi were conducted.…”

“…One promising candidate, the entomopathogenic fungus Acremonium hansfodii , is known to infect at least five insect species and other pests (Song 2006; Song 2007). More importantly, the entomopathogenic fungus (EPF), A. hansfordii , showed strong pathogenicity against T. urticae but did not significantly adversely influence N. barkeri (Shang et al . 2018).…”

“…In our previous study, we had found that the entomopathogenic fungus A. hansfodii could infect the prey effectively while it had less pathogenicity to the predatory mite (Shang et al . 2018), which is considered as a good basis for evaluating the compatibility of the two.…”

Efficacy of soil isolates of entomopathogenic fungi against the bulb mite, Rhizoglyphus robini (Acari: Acaridae)

“…Zare & W. Gams have potential to control some mite species (Chandler et al 2000). Most studies on efficacy of EPFs against mites have targeted ticks (Kaaya et al 1996;Kaaya & Hassan 2000;Fernandes & Bittencourt 2008), spider mites (Chandler et al 2005;Wekesa et al 2005;Shi & Feng 2009;Ullah & Lim 2017;Shang et al 2018;Khoury et al 2020) and eriophyoid mites (Latge et al 1988;McCoy 1996;Van der Geest et al 2000). To our knowledge, only three EPFs species have been tested against R. robini under laboratory or greenhouse conditions: Hirsutella kirchneri (Rostrup) Minter, Brady and Hall (Sztejnberg et al 1997), I. fumosorosea (Zemek et al 2018) and Metarhizium brunneum Petch (Ment et al 2020).…”