Acta Botanica Croatica, Vol. 43 No. 1, 1984.
Original scientific paper
The Activity of some Enzymes of Lipid Metabolism in Silver Fir Seeds (Abies alba Mill.) during Germination
Maja Kovač
; Hrvatska
Mercedes Wrischer
; Hrvatska
Abstract
The activity of some enzymes of lipid metabolism in silver fir seeds (Abies alba Mill.) varied in different ways in the embryo and the endosperm during germination. The activity was followed in the seeds from the Mašun region, which did not germinate at room temperature, and in the well germinated seeds from the Papuk region.
Lipase activity was measured at pH 8.5 (alkaline lipase) and at pH 5.5 (acid lipase). Mature seeds of both proveniences showed acid and alkaline lipase activity. As the activity of alkaline lipase in the endosperm did not change in any appreciable way before and during visible germination, we concluded that the alkaline lipase activity is not a limiting factor in germination. The activity of acid lipase and catalase increased somewhat after the penetration of the radicle in the well germinated seeds, while the activity of isocitrate lyase increased greatly. On the other hand, the activity of all enzymes assayed showed a constant decrease in the endosperm of the seeds from the Mašun region.
Acid and alkaline lipase and catalase were active before visible germination. Their activities were almost undetectable after radicle emergence while the activity of the nongerminated seeds from the Mašun region stayed constant (acid lipase, catalase) or showed a slow decrease (alkaline lipase). The embryo showed no isocitrate lyase activity.
The presence of microbodies was also examined in the electron microscope. Glyoxysomes were found alredy in the endosperm of mature seeds. Their number increased with germination. Microbodies were also present in the embryo before and during visible germination. It is suggested that the organelles under consideration do not function like glyoxysomes as there was no isocitrate lyase present in embryos. We conclude that in the embryo the lipids are not metabolised via the glyoxylate cycle as is true for the endosperm.
Keywords
enzimi; lipidni metabolizam; sjemenke jele; klijanje
Hrčak ID:
158911
URI
Publication date:
31.12.1984.
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