The German Cockroach Blattella Germanica — a Model for Insect Resistance Research

Introduction. When studying insect resistance, it is important to use standard laboratory cultures sensitive to insecticides. This includes the S-NIID german cockroach culture, which has been bred in the insectary of the Institute of Disinfection for 50 years. During the study, the S-NIID german cockroach (Blattella germanica) demonstrated a response to topical insecticide application consistent with that of known insecticide-sensitive cultures, such as UCR, JWax-S, SUS, and others.

The aim of the work is to description of the process of development of resistance of the German cockroach to pyrethroids from an evolutionary point of view (using the example of the sensitivity of 20 geographically separated populations of the German cockroach to 6 pyrethroids of different structures).

Materials and Methods. The study assessed the resistance of 20 German cockroach populations from various Russian cities to six active ingredients of the pyrethroid group. Statistical analysis was performed using the Finney method.

Results. Data on the resistance of the German cockroach (Blattella germanica) to pyrethroids when applied topically are presented. The study was conducted on samples from populations collected in Moscow, the Moscow and Kaluga regions, Yekaterinburg, Magnitogorsk, and Blagoveshchensk. A mosaic pattern of resistance was identified. Resistance to cypermethrin, the most commonly used insecticide, ranged from 5,4 to > 4000 in Moscow, from 417 to > 4000 in the Moscow region, from> 4000 in the Kaluga region, from 133 to > 833 in Yekaterinburg, and from 73 to 91 in Blagoveshchensk.

Conclusion. Resistant populations of the German cockroach are present in Russian cities from Moscow to Blagoveshchensk, with 95% of these populations characterized as resistant or highly resistant to pyrethroids. Rotation of active ingredients based on their mechanisms of action on insects is recommended.

Limitations of the study. The research aims to study the resistance of the German cockroach to pyrethroids of various structures and is of interest to specialists involved in disinfection activities in the field of disinfestation.

Contributions:
Eremina O.Yu. — study concept and design, data processing;
Olifer V.V. — data collection, introduction to insect culture and breeding.
All co-authors — conducted entomological and toxicological studies, wrote and edited the text, approved the final version of the article, and are responsible for the integrity of all parts of the article.

Funding. This study was not supported by any external sources of funding.

Conflict of interest. The authors declare no apparent or potential conflicts of interest related to the publication of this article.

Received: 30.01.2026 / Accepted: 25.03.2026 / Published: 10.04.2026

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