BACCIO BACCETTI AND THE COMPARATIVE SPERMATOLOGY OF INSECTS

Reconstructing the history of a scientific career is always a difficult task because there is the risk of ignoring events and achievements that may seem of minor importance to us but which to the person in question involved great commitment and dedication. Concerning Baccio Baccetti, however, there is no risk involved if we state that one of his major contributions to science was in the field of com parative spermatology, a topic that brought him to the attention of the international scientific community and rewarded him with honours and glory. During his research work in Florence’s Agricultural Entomology Station in the early 1960s, Baccetti, who already enjoyed the attention and kindness of Antonio Melis, Director of the Research Station, was able to take advantage of the enormous resolving power of transmission electron microscopy in the field of entomo logy. With uncommon farsightedness, Melis understood the innovative contribution of the new methodology and, thinking highly of Baccetti’s abilities and ingenuity, de cided to buy a small electron microscope, sensing that the new technology would lead to the advancement of kno wledge in agricultural entomology. In 1959-1960, there were two electron microscopes in Florence: the small Hitachi HS·6 in the Agricultural Entomology Station in Via Romana and a Siemens Elmiskop in the Institute of Histology of the University’s Faculty of Medicine at Careggi, directed by Prof. Allara. To learn the necessary fundamentals of the new techni que, Baccetti went to the Institute of Anatomy in Milan, directed by Prof. Aurelio Bairati, a famous professor of that city’s University. There he learned the basic techniques for preparation of materials and for interpretation of the results; he also met colleagues with whom he shared his first experiences and early successes in a field of Biology that would soon produce important results. Indeed, electron microscopy provided the opportunity to inve stigate and describe the internal organization of cells and organs, and from this knowledge to understand their functions. In Milan, Baccetti met Bairati’s son, Nanni, with whom he began to collaborate on the structure of germ cells and on the spermatogenesis of Drosophila and the dipteran agricultural pest Dacus (Bactrocera) oleae. I had recently returned from military service and I was asked to illustrate the flagellar complex of this dipteran described by the two Authors (1964), a drawing later published in Redia (Fig. IA). Unfortunately for me, it was not the custom at that time to cite the author of the drawing. These were the first reconstructions of the structure of a spermatozoon, an important basis for the functional interpretation of flagellar movement, first hypothesized by B.A. Afze1ius in 1959 and later confirmed by P. Satir and J. Gibbons (1963-1965). The movement of the sperma tozoon occurs through the interaction of the dynein arms present on subtubule A of each axonemal doublet and subtubule B of the adjacent doublet, with consequent reciprocal sliding of the microtubules involved. Nevertheless, this first approach to spermatology was not immediately followed up because Baccetti preferred to explore different topics, fully exploiting the resolving power of the new methodology. In the 1960s, he worked tirelessly and published important contributions on the fine structure of the myosin filament, on the ultrastructure of the intestine of insects, on the nervous system, on the supporting stroma of some organs, on the collagen fibre, on Malpighian tubules, and on the structure of the eyes of a spider. All these works helped Baccetti make a name for himself internationally. The first results on the structure of sperm cells also gave him the opportunity to describe the effects of sterilization of males of insect agricultural pests by the use of ionizing radiation. He obtained an Inatom contract with which he expanded the small electron microscopy laboratory he had set up in the back of the lecture hall in Via Romana and he hired a technician for the preparation of materials (Paolo Salvatici). In 1964, Baccetti won the competition for a chair of Zoology. He was to move to Padua, but by an agreement with the University of Padua and the consent of Prof. Pietro Omodeo, Professor of Zoology in the University of Siena, Omodeo went to Padua and Baccetti to Siena, as Professor of Biology and Zoology. Baccetti took up his new post in 1966 and the small Hitachi electron microscope went with him, the first electron microscope in the city of the Palio. The new methodology, together with the fervour that drove Baccetti to form a school of young researchers, attracted many followers, some of whom formed the first nucleus of the staff of the renewed Institute of Zoology of the Faculty of Mathematical, Physical and Natural Sciences. I had arrived in Siena the previous year, as assistant along with Paolo Salvatici, and we had been given the task of organizing the laboratories, including that of electron microscopy. The small Hitachi microscope was in constant use in the various lines of research but the instrument allowed only low resolution. Baccetti was keenly aware of this limitation and set out to purchase a new, more appropriate electron microscope. He tried to solve the problem by bringing an old Siemens to Siena from the Milan laboratory, but that choice did not improve the situation. He then bought a new Siemens Elmiskop IA electron microscope. Unexpectedly, Baccetti decided that the new instrument could only be used by himself and his associate Floriana Rosati. This produced a certain discontent and disaffection with research by some of the researchers. For me, they were very difficult months because I wanted to continue my ultrastructural studies but required the new microscope for the analysis of the flagellum of some spermatozoa. Hence, I was forced to use