Abstract
The spider mite Tetranychus pueraricola is widely distributed throughout Japan and it is common on kudzu vine but not on crops. Because this species has the second highest rm-value among tetranychid mites studied so far, there is a real possibility that T. pueraricola will get out of hand after invasion of agricultural crops. To better evaluate its potential severity as a pest, we examined the host range of five populations collected from kudzu vine. On leaf discs juvenile survival to adulthood was assessed, as well as egg production of young females over a period of five days. Out of 23 potential host plant species in 12 families tested, 70% or more larvae attained maturity and 15 or more eggs were subsequently laid by mites of all five populations on nine plantspecies (soybean, lima bean, kidney bean, kudzu vine, cowpea, spinach, apricot, rose and mulberry), whereas no or few larvae attained maturity on another four species (cucumber, tomato, chrysanthemum and Satsuma mandarin). On watermelon, strawberry and eggplant four of the five populations performed well. These results indicate that T. pueraricola has a broad potential host plant range, just like other polyphagous spider mite species, which are all serious pests. Its broad host range plus the second highest rm-value among Tetranychus species, suggest that this species has the potential to become a serious pest on agricultural crops.
