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  • Author: Waldemar Żukowski x
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Professor Adam Zając — a sketch on His scientific output on the 70th birthday

Seed germination in sedges: a short review

Five patterns of seed germination in the sedges of the genus Carex are presented, based on the literature data and the results of the authors' own research. They include the pattern of C. acutiformis, C. arenaria, C. remota, C. flava and C. communis. These patterns were constructed on the basis of seed specific requirements for development, such as stratification, temperature, dormancy and time of germination. Majority of sedges follow the pattern of C. acutiformis or C. remota. In both cases, stratification and either high or low temperature are essential for seed germination. Seeds that start to germinate early (C. remota pattern) are characterized by the absence of the distinct peaks of germination, as opposed to the C. acutiformis pattern with the germination peak in March. Our long-term investigations, conducted on the group of individuals in controlled conditions, revealed significant differences in seed size and the ability of seeds to germinate depending on the age of mother plants. We postulate that mother plant age is a new factor that should be considered in the construction of seed germination patterns.

Abstract

The list of alien vascular plant species only temporarily occurring in Wielkopolska refers to the previously published list of native and permanently established plants. Together, these two lists document the vascular flora of this region at the beginning of the 21st century. The current list, like the previous one, is a result of critical analysis of both contemporary and historical data, collected since the beginning of the 19th century. All information accessible in herbarium collections, publications and unpublished materials was used. A critical analysis was conducted at the taxonomic, nomenclatural, chorological and habitat levels, based on the verification of negative information not supported by sufficient arguments. The list is presented in an alphabetical order. Information on each species includes: family affinity, life form, geographic and historic status. In cases particularly disputable, the standard characteristic of a species was supplemented with an additional commentary.