Proteolytic activities in X Haynaldoticum sardoum seeds of different ages
1988
Galleschi, L. | Spano, C. | Bedini, G. | Floris, C. | Saviozzi, F. | Capocchi, A.
Carboxypeptidase, aminopeptidase and proteinase activities were measured in endosperms from dry and germinating x Haynaldoticum sardoum naturally aged seeds. Carboxypeptidase activity, present in dry seeds, decreased slightly during germination and remained nearly unchanged during the storage period. Aminopeptidase activity increased during germination in younger seeds, but decreased in non-viable seeds. Proteinase activity was absent in dry seeds, increased during germination in younger seeds and disappeared in the older ones. Proteinase activity was not recovered in old endosperms following transplantation of young embryos, and was recovered only to a very small extent in young endosperms following transplantation of old embryos. Young endosperms onto which young embryos had been transplanted gave maximum recovery of enzyme activity, although this was lower than in young intact seeds. These results suggest that the reduced or delayed availability of nutrients to the embryo axis is not the only factor causing the failure of seeds to germinate, the ageing process being a progressive phenomenon affecting both embryo and endosperm.
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