The development of larval resistance to a nucleopolyhedrovirus is not accompanied by an increased virulence in the virus

Citation
Ml. Milks et Jh. Myers, The development of larval resistance to a nucleopolyhedrovirus is not accompanied by an increased virulence in the virus, EVOL ECOL, 14(7), 2000, pp. 645-664
Citations number
65
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Environment/Ecology
Journal title
EVOLUTIONARY ECOLOGY
ISSN journal
0269-7653 → ACNP
Volume
14
Issue
7
Year of publication
2000
Pages
645 - 664
Database
ISI
SICI code
0269-7653(2000)14:7<645:TDOLRT>2.0.ZU;2-6
Abstract
Two laboratory experiments were conducted to examine the possible coevoluti on of cabbage loopers (Trichoplusia ni) and their S nucleopolyhedrovirus (T nSNPV). At the conclusion of Experiments 1 and 2, T. ni had respectively ev olved 4.4 x and 22 x resistance to TnSNPV. The higher level of resistance a chieved in Experiment 2 could be due to marginally stronger selection, poss ibly greater genetic variability in larval resistance to TnSNPV, or both. H owever, the evolution of resistance was not accompanied by an increased vir ulence of TnSNPV or a change in the restriction profile of the viral DNA wh en digested with BamHI, EcoRI, HindIII, PstI, SalI, SstI or XhoI. Little ge netic variability for virulence in the initial TnSNPV stocks, low mutation rates and possibly weak selection on the virus are some factors that may ha ve constrained the evolution of TnSNPV. We discuss our results in light of the geographic mosaic theory of coevolution and their implications for the use of TnSNPV as a biological control agent against T. ni.