Acta Botanica Croatica, Vol. 49 No. 1, 1990.
Original scientific paper
Seasonal Changes in the Chloroplasts of Cherry-Laurel Leaves
Jasmina Muraja
; Hrvatska
Nikola Ljubešić
; Hrvatska
Mercedes Wrischer
; Hrvatska
Abstract
Changes in fine structure and pigment content of chlo- roplasts in the leaves of cherry-laurel (Prunus laurocerasus L.) were studied during late autumn, winter and spring. The leaves, which grew up in autumn, could not finish their development and remained light-green in winter. Their chloroplasts were juvenile. Only the areas around the nectaries at the base of the leaves were dark-green. In these areas the chloroplasts had a well-developed thy- lakoid system, similar to that in fully grown leaves. In early spring the young leaves continued their differentiation; they became dark-green and developed normal chloroplasts. The differences in coloration of leaf laminas now disappeared. Such differences were again detectable in young leaves newly formed in spring. The reasons for the faster rate of development of the chloroplasts around the nectaries are discussed, and the high content of carbohydrates in the regions around the nectaries appears to be the most probable explanation.
Keywords
Hrčak ID:
159555
URI
Publication date:
31.12.1990.
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