Amyloplasten in Pollen von Betula pubescens

Mikroskopie ◽  
2021 ◽  
Vol 8 (01) ◽  
pp. 20-23
Author(s):  
T. Stebler
Keyword(s):  
Betula Pubescens

Содержание и состав жирных кислот суммарных липидов почек Betula pubescens, B. pendula, B. pendula var. carelica

2019 ◽  
Vol 66 (2) ◽  
pp. 146-150
Author(s):  
И. В. Морозова ◽  
Н. П. Чернобровкина ◽  
М. К. Ильинова ◽  
В. П. Пчёлкин ◽  
В. Д. Цыдендамбаев
Keyword(s):  
Betula Pubescens

Structure of plastids of a variegated Betula pubescens mutant

1972 ◽  
Vol 50 (9) ◽  
pp. 1835-1839 ◽  
Author(s):  
Niina Valanne ◽  
Terho Valanne
Keyword(s):  
Betula Pubescens ◽  
Tubular Structures ◽  
Pigment Analysis ◽  
Mature Leaves ◽  
Amoeboid Form

The patterns of variegation in the leaves of Betula pubescens only become evident in the mature leaves. However, the young plastids are also abnormal and pigment analysis does not suggest that the deformation of the plastids is caused by carotenoid deficiency. In mature leaves the mutant plastids are badly deformed. Among the most typical defects are an amoeboid form and the budding of peripheral reticular parts from the mutant plastids. These budding parts can easily be mistaken for mitochondria, but a closer inspection reveals differences in their tubular structures. These buds should therefore only be considered a special type of abnormal plastid.

Taxonomy of infraspecific variation in Betula pubescens Ehrh., with particular reference to the Scottish Highlands

1984 ◽  
Vol 85 (1-2) ◽  
pp. 13-26 ◽  
Author(s):  
A. S. Gardiner
Keyword(s):  
Multivariate Analysis ◽  
High Frequency ◽  
Betula Pubescens ◽  
Infraspecific Variation ◽  
Scottish Highlands ◽  
Betula Pubescens Ehrh

SynopsisThe variability of the pubescent birch and the probable existence of hybrids between it and two other birches make it a difficult species to classify at an infraspecific level. To some extent, the variation is geographical and to cover its distribution, three subspecies are proposed by the authors of Flora Europaea, sspp. pubescens, carpatica and tortuosa. Two subspecies are recognized in Britain, namely ssp. pubescens and ssp. odorata, but some confusion has arisen through the undetermined relationships between sspp. odorata, carpatica and tortuosa. The rejection of ssp. odorata is proposed as its application, in this case, differs from that intended by J. M. Bechstein, the original authority. An examination of the literature indicates that ssp. tortuosa and ssp. carpatica are probably indistinguishable (a conclusion supported by multivariate analysis) and that the epithet tortuosa can be applied to both taxa. The pubescent birch in the Scottish Highlands may be referred to ssp. tortuosa and, in addition, the high frequency of small-leafed individuals in some populations in the northwest and at higher altitudes, justifies the further distinction of var. microphylla Hartman.

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