Testing biocontrol potential of an indigenous predator against an invasive pest in New Zealand: Buchananiella whitei (Hemiptera: Anthocoridae) and the tomato red spider mite Tetranychus evansi (Acari: Tetranychidae)

The tomato red spider mite, Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) is an invasive pest that causes severe damage to solanaceous crops and has proven difficult to control using conventional acaricides or predatory mites. The minute pirate bug, Buchananiella whitei Reuter (Hemiptera: Anthocoridae), is a common but poorly studied anthocorid predator native to Australasia. This study investigated the development, survival, and reproduction (oviposition) of B. whitei when feeding on T. evansi under laboratory conditions, with Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as a control diet. Results showed that B. whitei successfully completed development and achieved high survival (83%) on T. evansi, with developmental durations not significantly different from those developed on E. kuehniella eggs. Predation capacity increased with age of instar. We also documented for the first time that B. whitei exhibits a variable number of immature instars (five or six) during development, even under controlled environmental conditions. In our oviposition experiment, adult females fed on T. evansi produced a significantly higher number of eggs (4.2 ± 1.0 per male-female pair) in 7 days. These findings provide the first evidence that B. whitei can develop and reproduce on T. evansi, suggesting its potential as a biological control agent against this invasive mite. Further work should assess its performance under greenhouse and field conditions, and its integration with other natural enemies within pest management programmes.