Dependence of Sitona lepidus (Coleoptera: Curculionidae) larvae on abundance of white clover Rhizobium nodules.

نویسنده

  • P J Gerard
چکیده

Sitona lepidus Gyllenhal (Coleoptera: Curculionidae) was first recognized in New Zealand pastures in the Waikato in March 1996 (Barratt et al., 1996). In Europe and North America, the species is considered to be a significant pest of clovers (Barratt et al., 1996 and references therein). However, white clover Trifolium repens L. (Fabaceae) is the key to profitability in New Zealand‘s pastoral industries, and the rate of spread and severity of clover damage experienced by farmers indicated that S. lepidus may become amongst the most serious pasture pest species in New Zealand. The only other Sitona species present in New Zealand is Sitona discoideus Gyllenhal (Barratt et al., 1996), a pest of lucerne, Medicago sativa L. (Fabaceae). All instars of this species damage root nodules (Allen, 1971) and the high degree of density-dependent mortality seen in Canterbury pastures is considered to arise amongst the neonate larvae during their establishment in the root nodules (Goldson et al., 1988). Observations by the author of S. lepidus larvae feeding on roots in glass-fronted display cases indicated that first instar larvae of this species fed on the fine roots of clover as well as root nodules. This paper reports the results of two experiments investigating the relationships between larval survival and development and the presence and abundance of root nodules.

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عنوان ژورنال:
  • Bulletin of entomological research

دوره 91 2  شماره 

صفحات  -

تاریخ انتشار 2001