BIOCHEMICAL AND BIOLOGICAL ASPECTS OF HONEY BEE (APIS MELLIFERA L.) LARVAL FOO

Total protein, protein patterns, zymograms and enzymatic activity of honey bee larval food were examined hourly by disc electrophoresis at pH 4.5. Larval weight was correlated to larval age and the relationship expressed in terms of regression equations. Factors that might lead to changes in larval food were studied.;The following conclusions were made. Worker larval weight can be used as an index of larval age. As the age of worker and drone larvae increased their diet became more complex. Royal and worker jelly were similar during the first 76 hours of age. Drone jelly differed from worker jelly by the presence of certain enzymes. Enzymatic activity of honey bee larval food was caste, sex and age dependent. Pollen contributed no detectable proteins or enzymes to the diet. The production of enzymes was partially controlled by the age of nurse bees. A selective mechanism for feeding larvae other than age of nurse bees was indicated. Some enzymes were probably secreted by the larvae. Changes in worker jelly during 74-76 hours of age may be related to caste determination. Worker jelly during the spring had higher amounts of total protein but isozymes and protein patterns similar to those found during the summer and fall. Isozymes in royal jelly were seasonal dependent. Lyophilization of jelly samples caused no significant changes in proteins or in enzymatic activity. A few worker larvae less than three days old were fed a unique yellow colored diet unusually high in pollen grains and total protein but reduced in enzymatic activity. These larvae developed into apparently normal workers. In queenless colonies the diet of worker larvae contained more food, a greater number of pollen grains, higher total protein, different protein and isozyme patterns than queenright colonies. The ratio of nurse bees to larvae affects the amount of diet fed but not the diet composition. In queenless colonies some drone larvae were fed as if they were queen larvae and their cells were converted to queen cells.