Salinity and drought are the main factors limiting the germination of seeds and development of lawn grasses. The study, carried out in controlled conditions, explored the effects of salt and drought stress as well as photoperiod on germination and morphological traits of seedlings of perennial ryegrass (Lolium perenne L.) and Kentucky bluegrass (Poa pratensis L.) lawn varieties. Germination capacity and mean germination time of seeds as well as the length and dry mass of shoots and roots of seedlings were determined. The germination of seeds was conducted on three levels of sodium chloride (NaCl) salinity (0, 100 and 200 mM) and four levels of drought stress using polyethylene glycol (PEG) solutions (0, −0.3, −0.6 and -1.2 MPa) in different photoperiod (0, 8 and 12 h of light) and temperature conditions (constant 25°C and variable 30/20°C). The obtained results showed that salinity decreased the germination capacity, the length of seedling shoots and roots, number of roots and dry mass of shoots and increased mean germination time (MGT) of seeds, especially of P. pratensis varieties. Drought stress increased mean germination time and limited germination capacity, shoot and root length and dry mass of L. perenne varieties only under the highest −1.2 MPa level, whereas P. pratensis -even at −0.3 MPa. In the conditions of salinity and simulated drought, germination capacity, shoot and root length and the mass of shoots of L. perenne and P. pratensis seedlings were closely correlated to each other. The results of this study indicate that germination capacity of P. pratensis varieties was modified by light duration. This species proved to be intolerant of lack of light during seed germination, while L. perenne varieties showed tolerance to photoperiod in this stage.

Growing acreage and changing consumer preferences cause increasing interest in the cereal products originating from organic farming. Lack of results of objective test, however, does not allow drawing conclusions about the effects of cultivation in the organic system and comparison to currently preferred conventional system. Field experiment was conducted in organic and conventional fields. Thirty modern cultivars of winter wheat were sown. They were characterized for disease infection including Fusarium head blight, seed sowing value, the amount of DNA of the six species of Fusarium fungi as well as concentration of ergosterol and trichothecenes in grain. The intensity Fusarium head blight was at a similar level in both systems. However, Fusarium colonization of kernels expressed as ergosterol level or DNA concentration was higher for the organic system. It did not reflect in an increased accumulation of trichothecenes in grain, which was similar in both systems, but sowing value of organically produced seeds was lower. Significant differences between analyzed cropping systems and experimental variants were found. The selection of the individual cultivars for organic growing in terms of resistance to diseases and contamination of grain with Fusarium toxins was possible. Effects of organic growing differ significantly from the conventional and grain obtained such way can be recommended to consumers. There are indications for use of particular cultivars bred for conventional agriculture in the case of organic farming, and the growing organic decreases plant stress resulting from intense fertilization and chemical plant protection.

The current conservation status of semi-natural grassland habitats in Poland indicates that actions for their restoration are necessary. Many of the degraded sites require the introduction of diaspores of representative species because other methods of improving their condition are not sufficiently effective. Meanwhile, little is known about the diaspores of native wild-flower species and the biology of their seeds. The aim of the present study was to find an answer to the question of which features of the seed material can guarantee the success of the introduction. The study covered 28 plant species of 4 non-forest natural habitats (codes: 6440, 6410, 6510, 6210) occurring in river valleys. Diaspores were collected in 2015–2017. Morphometric measurements of diaspores were performed, the weight of 1000 diaspores was determined and the germination capacity analysis was carried out in accordance with ISTA Rules. The analysis was made with the division into normal seedlings, abnormal seedlings, dead seeds and fresh ungerminated seeds. Species with similar parameters of seed material were selected using the method of hierarchical clustering and PCA analysis. Three groups of species were distinguished: (1) with good seed germination capacity (above 65%), which, regardless of weather conditions during the generative development, and despite the small size of diaspores, can guarantee successful introductions (Verbascum thapsus, Veronica longifolia, Daucus carota, Plantago lanceolata); (2) species of little suitability for introduction, due to the large proportion (over 50%) of dead seeds (Armeria maritima, Linaria vulgaris, Potentilla erecta, Centaurea stoebe, Sanguisorba officinalis, Cnidium dubium); (3) species with relatively large size of diaspores and low seed germination capacity, due to the high proportion of fresh ungerminated seeds which means dormant seeds (Lathyrus pratensis, Geranium pratense).

Abstract:The estimation of some wild fl owers seed material from the natural-valuable meadow habitats.The restoration of the species composition of the meadow habitats is often linked to the introduction of the typical species' seeds. The effectiveness of that treatment requires getting the acquired detailed knowledge of the germination biology of peculiar species. Eight typical plant species of four non-forest habitats of the river valleys, representing the following types: Cnidion dubii (6440), Molinion (6410), Arrhenatherion (6510) and Festuco-Brometea (6210) were investigated. The diasporas were collected in the years 2014-2015 on the meadows of PLH 140016 protection area near Mniszew (Kozienice county, Mazovian voivodeship). The ability of seeds' germination in the laboratory conditions was studied. It was stated that Cnidion and Molinion meadows' species require pre-chilling to break the seeds' dormancy, while the Arrhenatherion meadows and xerotermophilous swards do not require such treatment. The Allium angulosum, Plantago lanceolata, Achillea millefolium and Eryngium planum were characterized by high vigour and germination capability as well as the low share of dead seeds. The extremely drought in 2015 caused the decreasing in germination capability and increasing in the dead seeds' share. The preliminary studies, presented in this paper, show that Cnidion and Molinion meadows may be most difficult to restore because of the necessity of breaking the seeds' dormancy and higher sensitiveness for the unfavourable weather conditions during the seed ripening stage. The studies have practical significance for the works connected with the floristic diversity' increasing of threatened communities and the restoration of the destroyed meadow habitats.

The principle of the market competitiveness of breeding companies implicates a fast production of new varieties. One way to achieve this goal brings single seed descent (SSD) methodology, which requires kernels collection (18-23 days after pollination) , fast drying amd germination. Seed drying conditions influence the germination. In present work the influence of lightings: Sanyo LED and incandescent lamp vs. dark control during drying were studied. Kernels were harvested 18 and 23 days after pollination of wheat, triticale and barley cultivars grown in the same field experiment in 2015. It was found that: • the germination ability of non-mature kernels depends on all studied factors: lighting during drying, terms of harvesting and the interaction light * term; • non mature kernelsare more sensitive to drying conditions; • lighting during seeds drying can have a positive effect on ability to germination; • for breeding practice it would be better to harvest kernels at 23 DAF and dry them at room conditions under incandescent lamp.