Genetics of endosulfan resistance in Hypothenemus hampei (Coleoptera: Scolytidae): implications for mode of sex determination.
1995
Brun L.O. | Suckling D.M. | Roush R.T. | Gaudichon V. | Preisler H. | Robertson J.L.
The genetics of endosulfan resistance in Hypothenemus hampei (Ferrari) was studied through classical crosses to determine the degree of dominance and number of genes involved. After adult beetles were sprayed, mortality was recorded at 6 h and 7 d. Tests of the males from reciprocal F1 crosses indicated that resistance is sex-linked or that paternal chromosomes are inactive in the sons. Responses of F1 females after 6 h indicated degrees of dominance of -0.38 +/- 0.03 and -0.25 +/- 0.03 for RR X S and SS X R crosses, respectively. In contrast, dominance after 7 d was -0.17 +/- 0.02 and -0.02 +/- 0.02, apparently indicating a trend toward codominance over time. Responses of backcrosses of the F1 generation to both parental lines and of F2 progeny were inconsistent with results predieted when assuming simple Mendelian inheritance. These results illustrate the practical weaknesses of backcrosses in estimating the number of genes that control resistance in situations where bioassays are inconsistent or where discrimination between genotypes is poor.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by Wolters Kluwer