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How many genetic options for evolving insecticide resistance in heliothine and spodopteran pests?

Oakeshott JG, Farnsworth CA, East PD, Scott C, Han Y, Wu Y, Russell RJ - Pest Manag. Sci. (2013)

Bottom Line: The widely accepted paradigm for the development of insecticide resistance in field populations of insects is of selection for one or a very few genes of major effect.We discuss possible explanations for this paradox, including the likely embedding of these genes in regulatory cascades and emerging evidence for their arrangement in large clusters of closely related genes.We conclude that there could indeed be an unusually large number of genetic options for evolving resistance in these species.

View Article: PubMed Central - PubMed

Affiliation: CSIRO Ecosystem Sciences, 1700 Canberra ACT 2601, Australia. john.oakeshott@csiro.au

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Isozyme regions associated with organophosphorus (OP), pyrethroid (SP) and Bacillus thuringiensis resistance in Helicoverpa armigera in five studies using comparable electrophoretic methods. The reference isozyme lane shown is from fifth instar larvae of the Australian GR strain and the schematic lanes shown for the five studies are coded black for Chinese and grey for Australian strains. The numbers in the margins refer to relative mobility (Rm) values.
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fig01: Isozyme regions associated with organophosphorus (OP), pyrethroid (SP) and Bacillus thuringiensis resistance in Helicoverpa armigera in five studies using comparable electrophoretic methods. The reference isozyme lane shown is from fifth instar larvae of the Australian GR strain and the schematic lanes shown for the five studies are coded black for Chinese and grey for Australian strains. The numbers in the margins refer to relative mobility (Rm) values.

Mentions: The biochemical work on the esterases has gone a step further because of the facility of separating and staining individual esterase enzymes on native PAGE gels. The esterase isozyme profiles of the leipdopterans under discussion here are found to be considerably more complex than those of the dipteran and hemipteran precedents above. For example, Campbell30 found over 30 distinct isozymes in fourth instar H. armigera larvae alone, with several others also evident in other life stages of this species. Moreover greater staining intensities of several of the isozymes (6–9 in some cases) have been associated with OP or SP resistances in H. armigera,12,31,32H. punctigera,33H. virescens,27S. littoralis,34S. litura35 and S. exigua.36Figure 1 shows that at least four regions of the esterase zymogram, each containing multiple isozymes, have been associated with OP and pyrethroid resistance in H. armigera.12,30,32,37,38


How many genetic options for evolving insecticide resistance in heliothine and spodopteran pests?

Oakeshott JG, Farnsworth CA, East PD, Scott C, Han Y, Wu Y, Russell RJ - Pest Manag. Sci. (2013)

Isozyme regions associated with organophosphorus (OP), pyrethroid (SP) and Bacillus thuringiensis resistance in Helicoverpa armigera in five studies using comparable electrophoretic methods. The reference isozyme lane shown is from fifth instar larvae of the Australian GR strain and the schematic lanes shown for the five studies are coded black for Chinese and grey for Australian strains. The numbers in the margins refer to relative mobility (Rm) values.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3818700&req=5

fig01: Isozyme regions associated with organophosphorus (OP), pyrethroid (SP) and Bacillus thuringiensis resistance in Helicoverpa armigera in five studies using comparable electrophoretic methods. The reference isozyme lane shown is from fifth instar larvae of the Australian GR strain and the schematic lanes shown for the five studies are coded black for Chinese and grey for Australian strains. The numbers in the margins refer to relative mobility (Rm) values.
Mentions: The biochemical work on the esterases has gone a step further because of the facility of separating and staining individual esterase enzymes on native PAGE gels. The esterase isozyme profiles of the leipdopterans under discussion here are found to be considerably more complex than those of the dipteran and hemipteran precedents above. For example, Campbell30 found over 30 distinct isozymes in fourth instar H. armigera larvae alone, with several others also evident in other life stages of this species. Moreover greater staining intensities of several of the isozymes (6–9 in some cases) have been associated with OP or SP resistances in H. armigera,12,31,32H. punctigera,33H. virescens,27S. littoralis,34S. litura35 and S. exigua.36Figure 1 shows that at least four regions of the esterase zymogram, each containing multiple isozymes, have been associated with OP and pyrethroid resistance in H. armigera.12,30,32,37,38

Bottom Line: The widely accepted paradigm for the development of insecticide resistance in field populations of insects is of selection for one or a very few genes of major effect.We discuss possible explanations for this paradox, including the likely embedding of these genes in regulatory cascades and emerging evidence for their arrangement in large clusters of closely related genes.We conclude that there could indeed be an unusually large number of genetic options for evolving resistance in these species.

View Article: PubMed Central - PubMed

Affiliation: CSIRO Ecosystem Sciences, 1700 Canberra ACT 2601, Australia. john.oakeshott@csiro.au

Show MeSH
Related in: MedlinePlus