Abstract
Hydrolysis of Vicia faba primary root meristems in 5 NHC1 at 20°C, followed by reaction with the Feulgen reagent, was investigated using microdensitometry. Some differences in response were observed with prophase nuclei fixed in different solutions, but in general this type of hydrolysis leads to a plateau for stainability. After plateau hydrolysis most dye binding is completed within 15 min. For 3:1 alcohol-acetic fixatives, fixation times between 1 day and 13 weeks do not affect plateau stainability but shorter (½ hr) and longer (21 weeks) times give slightly lower values for dye content. Alcohol-acetic fixatives for short periods of time give the least variable results. A comparison of 5 N HCl hydrolysis at 20°C and 30°C shows that at the higher temperature the plateau is brief but not different in dye binding. However, the peak values for 1 N HCl hydrolysis at 60°C are significantly lower by 20%.