Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


апомиксис

Diagnostics of Seed Reproduction Mode in Some Species Calamagrostis Adans. from Flora of Peninsula Kamchatska

The mode of seed reproduction in four species Calamagrostis of peninsula Kamchatka (Russia) flora has been examined (C. langsdorffii (Link) Trin., C. lapponica Wahl., C. neglecta (Ehrh.) Gaertn., C. sesquiflora Trin.). In C. lapponica and C. neglecta studied plants are characterized by highly degree of pollen sterility (61,2 and 24,8% respectively) and significant variation of pollen grains size (CV = 17,4 and 18,7%), which is typical for apomictic forms.

Evolutionary role of apomixis: S. S. Khokhlov’s hypothesis in the light of modern data

In 1949 S. S. Khokhlov (one of the founders of the Russian scientifi c school on the problem of apomixes) proved the original conception of the progressive evolutionary role of apomixis. He contended that the basic direction of the reproductive system evolution in angiosperms is a gradual failure of sex reproduction and transition to apomixis. This hypothesis was heavily criticized and called a “scientist’s fantasy”. In the second half of the 20th century the discovery of recombination repair led to a reassessment of the role of meiosis in the evolution.

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