S. Mahunka szerk.: Folia Entomologica Hungarica 46/2. (Budapest, 1985)
quickly in a development of resistance to these chemicals. (Resistance can be parried only if 5 to 10 % of cattle are sprayed but those are treated in very short intervals.) On the basis of our studies two reasonable strategies for the pest management of Musca autumnalis are outlined below (see for more in Table 4). Table 4. Possibilities of control derived from the bionomics of populations of Musca autumnalis regular spraying of the places of overwintering (Oct-Apr.) 1st preoviposition period is long application of traps with pheromones (? development of "overwintering trap") slow-release devices, or, spraying a part of cattle with diptericids (maybe other part with repellents) pheromone trapping of overwintered specimens on pasture spraying of cattle with chemosterilants spraying of the places where the imagos spend the night change of pasture by evening mechanical spreading of cattle droppings (e.g. harrows) application of larvicids of species-specific nature on/in the cattle droppings 1) It seems a more perspective strategy to concentrate efforts on the improvement of repellents for spraying as control measures (see e.g. MINÁR and LAMATOVÂ, 1980).|lt has repeatedly been proved that in Hungary the larvae which play the most important role in the rapid decomposition of cattle droppings on the pastures in summer, are those of Musca autumnalis . As regards the dominance in the number of individuals in the larval populations, the dominance of Musca autumnalis is 7 to 25 % but owing to the big individual mass of larvae, they embody more than a half of the whole mass of dipteran larvae in most cases (e.g. a dominance of 10.03 %) Aranyosgadány, see PAPP, 1971) which can be regarded as an average value, is equal of a mas s-dominance of 56 . 74 %); their mass-dominance may exceed even 80 %. The imagos can - without sucking tears and blood - subsist on pasture flowers, on fresh cattle dung and urine, respectively on saliva, at most the females lay less eggs and their ovarlal cycles are prolonged. 2) We must study with carefully planned and executed trials, what happens, if the populations of Musca autumnalis are selectively exterminated in pastures (the most effective treatments are likely those, which are aimed at killing off the imagos returning from the overwintering places to pastures in the spring, see Table 4, or, chemosterilizing these imagos by one of the compounds of chemosterilizing effect (MELLAERT et al., 1983 a, b)).[ln this kind of a series of trials with contributions of microbiologists, coleopterologists, acarologists and dipterists, the dipterists would study, whether the larval populations of obligate coprophagous species - listed in the present paper - are able to take over the role of the larval populations of Musca autumnalis , at least partly so. A sequence of ideas can be as follows:
