Mass-rearing and quality control of olive fruit fly: Replacement of cellulose in larval diet and mating time asynchrony between wild and laboratory flies

Full text; Extensive efforts have been undertaken to replace or reduce the use of cellulose as olive fly larval medium bulk material by cheaper, readily accessible materials. Paper and synthetic 'vettex' gave promising results. Larval diet recycling and use of starter-finisher technology suggested practical re-use of larval diet, and possibility for young larval high-density use of the medium. It has been known that mating activity in laboratory strains spreads over a period of 4-5 h before the scotophase, contrary to wild strains, which exhibit mating activity almost exclusively within 1-0 h before the scotophase. In the field this could lead to mating activity strain separation, in case both sexes of laboratory strain are sterilised and released. In recent experiments it has been found that, although short photophases result in mating activity suppression towards the end of photophase in both strains, the above-described mating-time pattern in the 2 strains is always observed. Furthermore, no matter the L : D regime used with the laboratory strain, a shift to a longer or shorter photophase results in mating activity adaptation within 24h, i.e. the lab strain exhibits mating activity over a longer period before the scotophase as compared with the wild strain. An attempt to select for early-late mating pattern within the lab strain did not lead to success in spite of 6 generations of selection so far. (author)