EN
Carbon source and osmotic pressure are known to be of great importance in cultures in vitro. We compared the effectiveness of sucrose, maltose and mixtures of glucose with fructose in androgenic culture of isolated maize microspores. Also we examined changes in media during culture, focusing on osmotic pressure and sugar composition. The results suggest that osmotic pressure and kind of sugar have a great influence on androgenesis induction but much less influence on the number of macroscopic structures formed. In media containing sucrose the osmotic pressure rises significantly due to sucrose hydrolysis. In other media tested, changes in osmotic pressure are much smaller or not significant. These results suggest that the factors involved in androgenesis induction are different from those responsible for macroscopic structure formation. Changes in sugar composition and osmotic pressure increases in sucrose-based medium might decrease the effectiveness of androgenesis in maize microspore culture.