(Apis mellifera ligustica S.) During a period extending from March 1971 to March 1972, a queenrearing was achieved each month by means of a simple grafting or larvae. All the young larvae were issued from the same colony of Italian bees (A. m. tigustica S.). The rearing took place in two to four rearing colonies used in sucession. Two days before the queen eclosion, the queen cells were taken out and placed into an incubator, together with some forty bees nearly born, and about ten hive-bees which were fed with candy and pollen, the latter being stored before use at a temperature of -25 °C.On the 23 rd day of their cage-life, the virgin queens vers killed and weighed, the head being weighed separately. Then, the amount of 9-oxodec-2-enoic acid on the one hand and of 9-hydroxydec-2-enoic acid on the other hand was determined through gas chromatography. During the experiment, which covered 13 rearing series, 199 virgin queens were tested. The results were submitted to a statistical analysis.The quantitative analysis revealed the existence of an annual cycle in the two investigated acids and a cycle in the weight of queens. The cycle of the 9-oxodec-2-enoic acid is the clearer and the more stable of the two. It is not dependent on the rearing colony. A first maximum in the production appears in June and a second, of lesser importance, in December. The lowest quantities are obtained in August and September, as well as in March. The cycle of the 9-hydroxydec-2-enoic acid is partially similar to that of the 9-oxodec-2-enoic acid but is delayed as compared to it. Concerning the weight of queens, a maximum was observed in May, one month before that of the 9-oxodec-2-enoic acid. The weights decrease regularly until November and there is no increase before spring.A parallelism was etablished between the annual cycle of the 9-oxodec-2-enoic acid and that of the 10-hydroxydec-2-enoic acid produced by the worker bees which was detected previously (PAIN and ROGER, 1970).The relations between the secretion cycles of the pheromonal substances and different environmental factors (photoperiod, temperature, food resources) are discussed. The part played by the worker bees under this respect is also discussed, the worker bees being studied under variable physiological conditions according to which moment of the year they were selected to act as companions for the queens. Descripteurs : Saison écologique, acide céto-9 décène-2 oïque, acide hydroxy-9 décène-2 oïque, acide hydroxy-10 décène-2 oïque, phéromone de déclenchement, phéromone d'amorçage, Apis m. ligustica, reine insecte, poids. RÉSUMÉ

Le &dquo;'Ce (période de 32,5 jours) a été utilisé pour marquer à la dose de 500 !tCi par litre un sirop de sucre qui a été donné en nourrissement à 7 colonies d'abeilles à raison de 1 litre par semaine entre le 23 mars et le 13 avril 1973. Les ruches utilisées étant du modèle Dadant, les hausses ont été posées le 19 avril au début d'une importante miellée de colza. La radio-activité résiduelle dans ces hausses a été mesurée le 29 mai, à la fin de la miellée. Dans tous les cadres de toutes les ruches expérimentales on a pu mettre en évidence la présence de l 4lCe dans les réserves de miel. Cependant, la radio-activité n'était pas répartie de façon uniforme certains cadres étant plus actifs que d'autres. La radio-activité retrouvée en fin d'expérience dans les hausses variait entre 2,4 et 6,3 1)(> de la radio-activité résiduelle théorique. Elle correspondait au passage de 2,0 à 8,4 grammes de saccharose dans chaque kg de miel récolté. La signification théorique et pratique des remontées de sucre de nourrissement dans les hausses est discutée, notamment en ce qui concerne le risque de pollution du miel par des substances médicamenteuses.