How host-specific is diamondback moth? A study on performance with brassicaceous and non-brassicaceous species
Diamondback moth，Plutetla xylostella(L.)(Lepidoptera：Plutellidae)is oligophagous on Brassl‘Caceae.but is known to have occasionally switched to also feed upon hosts of other plant families. The spider flower，Cleome hassleriana Chodat(Capparaceae)and garden nasturtium Tropaeolum majus L.(Tropaeolaceae)are taxonomically distinct but chemically related to Brassicaceae by containing glucosinolates.Both of these plant species can occur sympatrically with wild crucifers，and so could potentially harbor P.xylostella populations，perhaps providing bridge hosts until crop plants ale available.But these non-brassicaceous plants have never been reported to be infested with P. xylostella in the region. In this extensive laboratory and greenhouse study，we tested ovipositional preferences of P.xylostella in a freechoice situation using two Brassicaceae viz.conventional canola，Brassica napus L.，flixweed，Descurainia sophia(L.)Webb ex Prantl，and two non-Brassicaceae viz.C. hassleriana and T.majus.No-choice tests were conducted to investigate key life history parameters i.e.，survival，developmental time，herbivory，pupal weight，silk weight，adult weight，forewing wing area，and longevity(without food)for both female and male specimens when reared on all four plant species.Although several P.xylostella developmental parameters were similar on C.hassleriana and T.majus as on more preferred Brassicaceae，non-hosts lacked the ability to compensate as well for P.xylostella herbivory.Host shifting by P.xylostella is evidently a strategy for population survival when preferred hosts are not available，and is a strategy that may predispose new generation offspring for enhanced migratory capability.
Rana M.Sarfraz Lloyd M.Dosdall Andrew B.Keddie
Department of Biological Sciences,University of Alberta,Edmonton,Alberta,Canada T6G 2E9 Department of Agricultural,Food and Nutritional Science,University of Alberta,Edmonton,Alberta,Canad
国际会议
北京
英文
102-111
2006-10-24（万方平台首次上网日期，不代表论文的发表时间）