Compatibility of Synthetic and Natural Pesticides with a Pest Control Agent

Jenn Hoskins
14th June, 2024

Compatibility of Synthetic and Natural Pesticides with a Pest Control Agent

Image Source: Natural Science News, 2024

Key Findings

  • The study by the University of California assessed the compatibility of the predatory mite Phytoseiulus longipes with various pesticides to improve pest control strategies
  • Pyrethroids (cypermethrin, deltamethrin) and organophosphates (dimethoate, chlorpyrifos) were highly harmful to P. longipes, causing significant mortality and long-lasting effects
  • Azadirachtin and Hirsutella thompsonii were slightly harmful to P. longipes adults but became harmless within a few days, making them more suitable for integrated pest management (IPM) programs
The study conducted by researchers at the University of California focuses on the compatibility of the predatory mite Phytoseiulus longipes with various pesticides, aiming to enhance the biological control of Tetranychus evansi, an invasive pest in Africa and other regions[1]. This research is crucial as it explores environmentally friendly pest management strategies, reducing reliance on chemical pesticides. Phytoseiulus longipes has shown promise in controlling T. evansi, but its interaction with commonly used pesticides needed investigation. The study tested the effects of two pyrethroids (cypermethrin and deltamethrin), two organophosphates (dimethoate and chlorpyrifos), one nicotinoid (imidacloprid), two acaricides (propargite and abamectin), two naturally derived pesticides (oxymatrine and azadirachtin), and one entomopathogenic fungal-based formulation (Hirsutella thompsonii) on P. longipes eggs and adults. The results revealed that azadirachtin and H. thompsonii had slightly harmful effects on P. longipes adults. Imidacloprid, propargite, abamectin, and oxymatrine were moderately harmful to both eggs and adults. In contrast, cypermethrin, deltamethrin, dimethoate, and chlorpyrifos were highly harmful to both life stages, with their persistence remaining high even after 31 days of application. These findings align with previous studies on pesticide effects on predatory mites. For instance, research on Tetranychus urticae management highlighted the varying susceptibility of predatory mites to different miticides, emphasizing the need to evaluate each natural enemy individually when developing pest management programs[2]. Similarly, the synergy between matrine and Lecanicillium muscarium in controlling Bemisia tabaci demonstrated the complexity of biochemical interactions between pesticides and natural enemies[3]. The current study's detailed analysis of lethal and sublethal effects provides a comprehensive understanding of how different pesticides impact P. longipes. The researchers used a reduction coefficient (Ex) to classify the toxicity of each pesticide based on IOBC categories. This classification helps in decision-making for integrated pest management (IPM) programs, ensuring that the use of P. longipes is compatible with other pest control measures. Residual persistence bioassays showed that azadirachtin's harmful effects dissipated after four days, while abamectin, oxymatrine, and H. thompsonii became harmless to P. longipes ten days post-spraying. Propargite and imidacloprid were considered harmless after 20 days. These insights are critical for timing pesticide applications to minimize their impact on beneficial predators like P. longipes. In summary, the University of California's study provides valuable information for improving IPM strategies by integrating biological control agents like P. longipes with selective pesticide use. This approach not only enhances the effectiveness of pest management but also promotes environmental sustainability by reducing the reliance on harmful chemical pesticides.

AgricultureBiotechAnimal Science

References

Main Study

1) Compatibility of synthetic and biological pesticides with a biocontrol agent Phytoseiulus longipes (Acari: Phytoseiidae)

Published 13th June, 2024

https://doi.org/10.1007/s10493-024-00926-3

Related Studies

2) Not all predators are equal: miticide non-target effects and differential selectivity.

https://doi.org/10.1002/ps.5754

3) Toxicological and biochemical basis of synergism between the entomopathogenic fungus Lecanicillium muscarium and the insecticide matrine against Bemisia tabaci (Gennadius).

https://doi.org/10.1038/srep46558


Related Articles

An unhandled error has occurred. Reload 🗙