Published online by Cambridge University Press: 31 May 2012
Although several studies have been conducted on the mating habits of laboratory-reared onion maggots confusion exists as to whether the females mate more than once. In Holland, Ticheler and Noordink (1968) using a radio-tracer technique demonstrated a second mating in the female but later work by Robinson (1977) suggested that mating occurred only once. North American workers using whiteeyed mutants in crosses with red-eyed flies found that the female mates only once (Broersma and Luckman 1968) and earlier data developed in our laboratory support this finding (McEwen et al. 1973). That the female mates only once is suggested also by reports showing that increasing the ratio of males to females does not increase egg production and that the early removal or death of the males does not reduce the number of eggs laid or the percentage of hatch (Missonier and Stengel 1966; Robinson and Zurlini 1979).