Laboratory and field evaluation of an entomopathogenic fungus, Isaria cateniannulata strain 08XS‐1, against Tetranychus urticae (Koch)

Abstract

BACKGROUNDThe two‐spotted mite, Tetranychus urticae Koch, is one of the most serious mite pests of crops throughout the world. Biocontrol of the mite with fungal agents has long been paid much attention because of the development of insecticide resistance and the severe restriction of chemical pesticides. In this study, the efficacy of submerged conidia of the entomopathogenic fungus Isaria cateniannulata strain 08XS‐1 against T. urticae eggs, larvae and female adults was evaluated at different temperatures and humidity in the laboratory and under field conditions.RESULTSThe results showed that a suspension of 2 × 107 submerged conidia mL −1 caused the highest mortalities of mite eggs, larvae and females (100, 100 and 70% respectively) at 100% relative humidity and 25 °C in the laboratory. In the field experiments against the mites, a suspension of 2 × 108 submerged conidia mL −1 achieved significant efficiency – the relative control effects were 88.6, 83.8 and 83%, respectively, in cucumber, eggplant and bean fields after 10 days of treatment.CONCLUSIONThe results suggest that the I. cateniannulata strain 08XS‐1 is a potential fungal agent, with acceptable production cost of conidia, against T. urticae in the field in an area such as southwestern China with higher air humidity. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Laboratory Evaluation of an Entomopathogenic Fungus, Isaria fumosorosea wize pa208 against Two-spotted Spider Mite, Tetranychus cucurbitacearum (SAYED)

“…Mite control programes aim at maintaining two-spotted spider mite at low levels throughout the year, i.e. the populations are allowed to reach an acceptable level before the mites become difficult to control (Zhang, et al 2016). Therefore, the important targets in integrated pest management (IPM) of the mites are the eggs and females.…”

Pathogenic differences of the entomopathogenic fungus Isaria cateniannulata to the spider mite Tetranychus urticae (Trombidiformes: Tetranychidae) and its predator Euseius nicholsi (Mesostigmata: Phytoseiidae)

“…The predatory mite E. nicholsi had also shown potential as a biological control agent of T. urticae (Zheng and Jin 2008 , 2009 ). We previously demonstrated that I. cateniannulata has a high efficiency against T. urticae and negligible effects on E. nicholsi (Zhang et al 2014 , 2016 ).…”

“…in forest ecosystems (Zhang et al 2007a , b ; Li et al 2011 ). In our recent papers, we have discussed the efficacy of I. cateniannulata in controlling T. urticae while having little, if any, detrimental effects on E. nicholsi (Zhang et al 2013 , 2014 , 2016 ).…”

“…Little information is currently available on differences in pathogenicity of I. cateniannulata to T. urticae and E. nicholsi , we initiated a comparative study on the infecting processes and micromorphological behavior of submerged conidia versus aerial conidia of I. cateniannulata on T. urticae and E. nicholsi. As in many other fungal entomopathogens, the submerged and aerial conidia in cultures of I. cateniannulata are the two propagules regularly used on target pests (Zhang et al 2016 ). The primary goal of our investigation was to enhance our understanding of the causes for the differences in pathogenicity of I. cateniannulata conidia to T. urticae and E. nicholsi , and to enrich our knowledge in the complex interactions between the two biological control agents.…”

De novo transcriptome sequencing of Isaria cateniannulata and comparative analysis of gene expression in response to heat and cold stresses

“…Isaria cateniannulata (Z. Q. Liang) Samson & Hywel-Jones [22] (formerly Paecilomyces cateniannulatus [23]) is a highly virulent entomopathogenic fungus belonging to hyphomycetes [23, 24]. It can infect insect pests such as Lepidoptera [23–25], Coleoptera [23], and Hemiptera [23, 26], as well as mites [27] and nematodes [28]. This fungus is one of the dominant entomopathogenic fungi in several ecosystems including pine plantation [29] and tea plantation [30].…”