Changes in tissue polyploidization during development of worker, queen, haploid and diploid drone honeybees

Cytophotometric measurements were made of DNA content in nuclei stained by the Feulgen method and direct measurements of length and width of nuclei were also made. There was an enormous increase of polyploidization in larvae 4 days old, from an average of 110 n in workers through 112 n and 200 n in haploid and diploid drones to 320 n in queens. Mean DNA content in nuclei of haploid drone, diploid drone, worker and queen larvae were in the ratios 1.0 : 1.7 : 1.1 : 3.1. Since diploids began with twice as much DNA as haploids, polyploidization was about twice as fast in haploid drone larvae as in worker ones and only a little slower in diploid drone larvae than in haploids. A drastic decrease of polyploidization was found in early pupae from 5 n in haploid drones and workers to 8 n in diploid drones and queens. Some increase of average polyploidization was found in imagines, from 7 n in haploid drones through 8 n in diploid drones and workers to 10 n in queens. Relative polyploidization in imagines as determined by both DNA content and volume of cell nuclei may be presented in the following succession: workers, 1.0; haploid drones, 1.0; diploid drones, 1.2; queens, 1,5. Since diploids began with twice as many chromosomes as haploid drones, the relative rate of polyploidization up to the imago may be presented in the following sequence: workers, 1.0; diploid drones, 1.2; queens, 1.5; haploid drones, 2·0. Diploid drones showed sexualities ranging from intersex to female.