title: A malathion resistance gene associated with increased life span of the rusty grain beetle, Cryptolestes ferrugineus (Coleoptera: Cucujidae).
abstract: The life span of the rusty grain beetle, Cryptolestes ferrugineus, was determined at 30 degrees C, 75% relative humidity (RH) for virgin and mated adults of a malathion-resistant strain (BC6RR), a malathion-susceptible strain (SS), the F1 progeny of a cross between resistant females and susceptible males (RS), and an outbred strain (GV). The BC6RR strain was derived from the SS strain by incorporating the malathion resistance gene into the susceptible genome with six backcrosses and recovery of heterozygous resistant F1 adults between crosses. The mean life span of virgin, malathion-resistant adults (BC6RR and RS) was 37 weeks; the mean life span of virgin, susceptible adults (SS and GV) was 32 weeks. Resistant virgin adults lived significantly longer (15-16%) than susceptible virgin adults, and mated resistant adults lived significantly longer (3-20%) than mated susceptible adults (p < .05). Since C. ferrugineus has a relatively long reproductive period and females with the longest life spans produce the most offspring, life span can be considered an important component of fitness in this insect. The malathion resistance gene did not reduce fitness, and this gene or genes closely linked to it may be responsible for increasing life span in C. ferrugineus.
authors: Agriculture Canada, Research Station, Winnipeg, Manitoba.
authors: N D
authors: ND
authors: White
authors: R J
authors: RJ
authors: Bell
mesh_terms: D000818:Animals; D001517:Coleoptera / Q000187:drug effects / Q000235:genetics*; D005260:Female; D017344:Genes, Insect; D007305:Insecticide Resistance / Q000235:genetics; D008136:Longevity / Q000235:genetics*; D008294:Malathion / Q000494:pharmacology*; D008297:Male
chemical_list: D008294:Malathion