Evaluation of Natural and Factitious Food Sources for Pronematus ubiquitus on Tomato Plants

Abstract

<i>Pronematus ubiquitus</i> (McGregor) is a small iolinid mite that is capable of establishing on tomato plants. Once established, this mite has been shown to control both tomato russet mite, <i>Aculops lycopersici</i> (Tryon) (Acari: Eriophyidae), and tomato powdery mildew (<i>Oidium neolycopersici</i> L. Kiss). In the present study, we explored the effects of a number of alternative food sources on the oviposition rate in the laboratory. First, we assessed the reproduction on food sources that <i>P. ubiquitus</i> can encounter on a tomato crop: tomato pollen and powdery mildew, along with tomato leaf and <i>Typha angustifolia</i> L. In a second laboratory experiment, we evaluated the oviposition rate on two prey mites: the astigmatid <i>Carpoglyphus lactis</i> L. (Acari: Carpoglyphidae) and the tarsonemid <i>Tarsonemus fusarii</i> Cooreman (Acari: Tarsonemidae). Powdery mildew and <i>C. lactis</i> did not support reproduction, whereas tomato pollen and <i>T. fusarii</i> did promote egg laying. However, <i>T. angustifolia</i> pollen resulted in a higher oviposition in both experiments. In a greenhouse trial on individual caged tomato plants, we evaluated the impact of pollen supplementation frequency on the establishment of <i>P. ubiquitus</i>. Here, a pollen addition frequency of every other week was required to allow populations of <i>P. ubiquitus</i> to establish.