The reproductive biology of glossopterid gymnosperms—A review
نویسندگان
چکیده
We review recent advances on glossopterid reproductive biology and their implications for seed plant phylogeny the ecology of this widespread Permian Gondwanan group. Microsporangiate organs are interpreted to have been arranged in loose compound cones—an organization that evokes comparisons with Ginkgoales, Cordaitales early conifers. The pollen was typically taeniate, bisaccate, primarily adapted wind dispersal. diverse ovuliferous generally incorporated some form marginal flange or wing. In most cases, wing probably protective, wrapping around ovules during development. However, we postulate conspicuous flanges were potentially analogous angiosperm petals, functioning as corolla-like guides attract insect pollinators. arrangement seed-bearing polysperms adnate subtending leaf a fertiliger glossopterids represented another means protecting ovules. highlighting polysperm against attached might increased showiness ovule-bearing part other detachment may aided anemochory by retarding fall through rotation dispersal extant Tilia. microgametophyte is characterized short, weakly branched, haustorial tube, release motile sperm cells. At least seeds express polyembryony. Mature possessed various micropylar modifications entrapment pollen, winged bulbous expansions outer integument aid possibly hydrochory. Vegetative regeneration response damage occurred via epicormic buds development lignotubers.
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ژورنال
عنوان ژورنال: Review of Palaeobotany and Palynology
سال: 2021
ISSN: ['1879-0615', '0034-6667']
DOI: https://doi.org/10.1016/j.revpalbo.2021.104527