Volumen 48 (2017): Edición 1 (December 2017)

The paper presents an analysis of problems of arable field weeds discussed by Polish authors in 2853 botanical scientific works published in the years 1870-2015. The research included both widely available publications and scientific works that appeared in Polish in regional and local journals, as well as the brief conference proceeding. The thematic structure of Polish studies on segetal weeds consists of several levels and includes eight main thematic groups and 51 subgroups. The review and multi-subject works were included in the ninth group. Taking into account the number of publications, main thematic groups are ranked as follows: (1) Weed flora and vegetation: structure, distribution and dynamics; (2) Weediness of different crop types, crop fields and fallow lands; (3) Interactions between weeds and the environment; (4) Biology and weed development; (5) Variability, taxonomy and weed diagnostics; (6) Research methodology; (7) Extinction and protection of weeds; (8) Weeds of archaeological localities.

Genetic diversity among 20 Lathyrus sativus L. accessions from Ethiopia was investigated by using Cleaved Amplified Polymorphic Sequence (CAPS) markers. Genetic diversity statistics showed presence of a moderate level of genetic variation in the analysed accessions (P = 69.77%, Hs = 0.278). Analysis of genetic differentiation showed existence of a low level of differentiation between accessions, which accounted for only 7% of the total variation and most of the variation was due to differences among individuals within accessions (93%). Both cluster and principal coordinate analyses revealed minimal grouping of accessions based on geographical origin implying that local varieties of grass pea with different genetic backgrounds were distributed among various administrative regions in Ethiopia. The CAPS markers employed in our study demonstrated the utility of such markers for genetic diversity assessment in grass pea.

In this paper, we present preliminary results from the study on the effect of fruit storage period on seed germination in Solidago ×niederederi and its parental species (S. canadensis and S. virgaurea). We aimed to test the hypothesis that a long fruit storage period (i) reduces the final percentage and speed of seed germination, as well as (ii) increases the number of dead seeds among non-germinated ones. We used fruit samples collected in Kraków, southern Poland, in 2013 and 2016, designating two different fruit storage periods of 3.5 years and 0.5 years, under dry, room temperature conditions. Seeds of all the observed species presented remarkably higher final percentage of germination after the short storage period than after the long one. The seeds subjected to the short fruit storage period achieved significantly higher values of Timson’s index and coefficient of velocity, as well as significantly lower values of the mean germination time than samples subjected to the long fruit storage period. After the long storage period, a significantly higher number of dead seeds among non-germinated seeds was found in S. ×niederederi and S. virgaurea. The performed studies showing that the long fruit storage period led to low contribution of germinated seeds in S. ×niederederi and its parental species suggested that the longtime seed desiccation had a negative impact on final germination. Considering that the hybrid can be potentially cultivated for scientific, medicinal or ornamental purposes, the suggested fruit storage period, under dry, room temperature conditions, should be shorter than three years. However, we realize that the response to long storage may vary in different populations and, therefore, further investigations are needed.

The paper considers current ranges, population dynamics, habitats, threats and conservation measures of Ophioglossaceae of the Ukrainian flora. Only one specimen of Botrychium simplex was discovered in herbarium at the begining of the 19^th century. Taxonomical status of Ophioglossum azoricum in Ukraine needs additional studies. Other species of the family remain rare in Ukraine; there are only two reliable current localities of B. virginianum, and seven of B. matricariifolium. The number of B. multifidum, B. lunaria and Ophioglossum vulgatum localities have been decreasing since 1980 in comparison with the previous period, especially in the lowland part of the country. This tendency is accompanied by a very low stability of well-known populations – only some of them have been occurring from before 1980 up to modern times. Current conservation of Ophioglossaceae species in the protected areas is insufficient; it is necessary to create some new and enlarge some of the existing nature protection areas and include Botrychium simplex and Ophioglossum vulgatum in the Red Data Book of Ukraine.