Early phases in in vitro culture of tomato cotyledons: Starch accumulation and protein pattern in relation to the hormonal treatment

Summary Tomato cotyledon explants, cultured in vitro in the presence of sucrose, were subjected to different hormonal treatments to establish whether the induction of different organogenic programmes could be correlated with differences in starch accumulation and protein electrophoretic pattern. The cytohistological changes in explants over the first 15 days of culture were studied by light and electron microscopy. It was found that starch accumulation occurs under all conditions, though varying in duration and amount. Over the first 2 days of culture the protein electrophoretic pattern changes in a similar way under all conditions, while after 7 days changes take place which are probably related to the different developmental programmes induced by the treatments.Abbreviations BOA benzisoxazole-3-acetic acid - 2,4-D 2,4 dichloro-phenoxyacetic acid - DTT dithiothreitol - GA₃ gibberellic acid - HF hormone-free - LM light microscopy - LSB Laemmli sample buffer - PAGE polyacrylamide gel electrophoresis - PMSF phenylmethylsulfonylfluoride - TEM transmission electron microscopy - ZR zeatine riboside