Spider Mites: Genetic Models to Inform Herbivore and Chelicerate Biology

Area of Science:

• * Arthropod biology and evolutionary genetics.
• * Genomics and comparative genomics of Acari (mites and ticks).

Background:

• * Spider mites (Tetranychidae) are significant agricultural pests and powerful genetic models.
• * They are crucial for understanding chelicerate biology, pesticide resistance, and host plant adaptation.
• * Previous genomic studies of *Tetranychus urticae* revealed gene family expansions and horizontally acquired genes.

Purpose of the Study:

• * To review spider mite biology and experimental tractability.
• * To highlight recent genome-enabled findings in spider mite research.
• * To showcase the potential of spider mites for understanding Acari and chelicerate biology, adaptation, and evolution.

Main Methods:

• * Comparative genomics across Tetranychidae species with varying host plant ranges.
• * Quantitative genetic methods to identify loci underlying adaptive traits.
• * Functional studies utilizing RNAi and gene editing.

Main Results:

• * Genome sequencing of *Tetranychus urticae* identified gene expansions and horizontally acquired genes associated with broad host plant adaptation.
• * Comparative genomics is revealing links between gene content and host plant breadth in different Tetranychidae species.
• * Advanced genetic techniques enable the study of adaptive traits and their underlying genetic architecture.

Conclusions:

• * Spider mites offer a tractable system for investigating fundamental biological questions.
• * Genome-enabled research is advancing our understanding of adaptation, evolution, and pesticide resistance.
• * Spider mites hold significant potential for informing broader fields of arthropod biology and evolutionary genetics.