Development and reproduction of Rhizoglyphus robini Claparéde (Astigmata: Acaridae), an emerging pest in Indonesia, on six host plants

The bulb mite, Rhizoglyphus robini Claparède, is an important pest of plants with bulbs, corms or tubers. The mite is ubiquitously found infesting subterranean organs of crops in fields, greenhouses, and storage facilities. Although the mite is of economic and biosecurity importance, the information about its biology is still obscure. In this current study, the development and reproduction of R. robini on carrot, taro corm, ginger rhizome, shallot bulb, garlic clove, and onion bulb were studied under laboratory conditions. The intrinsic rate of increase (r_m) of the mite was estimated by an equation relating the mite reproduction rate to its pre-reproductive time. The results showed that the development, fecundity, and r_m of the mite were significantly affected by the host plant variability. The mite development lasted for 9.80 to 12.56 days, the fecundity was 45.05 to 242.00 eggs per female, and the r_m was 0.210 to 0.271. The higher r_m values of R. robini on carrot, shallot, garlic, and onion alarms the potential of the mite to become a new threat to those commodities. The biological information of R. robini obtained in this study can be applied to evaluate the differential susceptibility of the tested host plants.