THE MANIPULATION OF ARTHROPOD REPRODUCTION BY WOLBACHIA ENDOSYMBIONTS

Wolbachia are intracellular bacteria that manipulate the reproduction of their arthropod hosts. The nature of the manipulation varies with W olbachia strain, arthropod taxa, and arthropod genetic system. Nonreci procal and reciprocal reproductive incompatibilities, sex ratio biases , and induction of thelytoky are some of the results of Wolbachia symb iosis. The Wolbachia present in the predatory mite Metaseiulus occiden talis are genetically similar to those found in insects, and are corre lated with nonreciprocal incompatibility in crosses between infected m ales and uninfected females. The incompatibility phenotype includes re duced numbers of eggs, shriveled eggs, and a male-biased sex ratio of the few resulting progeny, which may be related to the parahaploid gen etic system of this phytoseiid mite.