Gibberellin influence on the morphogenesis of the moss Bryum argenteum Hedw. in in vitro conditions

The moss Bryum argenteum Hedw. was treated with gibberellins as well as some inhibitors of gibberellin biosynthesis in order to investigate their influence on B. argenteum morphogenesis. Generally, gibberellins have not been chemically identified in bryophytes, while other groups of classical phytohormones (auxins, cytokinins, abscisic acid and ethylene) have been chemically identified in these plants. The in vitro culture of the moss Bryum argenteum was established from sterilized spores. The apical shoots of untreated gametophytes grown in vitro were used to investigate the influence of different substances on secondary protonema and on the growth and multiplication of the gametophytes. B. argenteum reacts differently to the growth regulators applied. Both gibberellins applied in vitro (GA3 and GA7) have a positive effect on B. argenteum morphogenesis. Shoot multiplication was negatively affected by three tested growth retardants (ancymidol, BX-112 and chlorocholine chloride), while these substances did not have such strong effects on the moss protonema development.Projekat ministarstva br. 143031 i 14301

In vitro culture and apogamy: Alternative pathway in the life cycle of the moss Amblystegium serpens (Amblystegiaceae)

In vitro culture of the moss Amblystegium serpens (Amblystegiaceae) was established on hormone-free Murashige and Skoog (MS) medium that contained a half amount of MS micro- and macro- mineral salts and vitamins, 100 mg/l myoinositol, 30 g/l sucrose, and 0.70% (w/v) agar. Spores were germinated and primary protonema developed on the above medium at 16 h day/8 h night 25±2ºC, 60-70% air humidity, and irradiance of 47 μmol/m2s. Three months after development of primary protonema, seven sporophytes appeared directly from primary protonema without generation alternation. The phenomenon of apogamous sporophyte formation is very rare, both in nature and under in vitro conditions. This is the first report of apogamy induced by Amblystegium serpens

Development of the moss Pogonatum urnigerum (Hedw.) P. Beauv. under in vitro culture conditions

Pogonatum urnigerum (Polytrichaceae) in vitro culture was established from spores collected in nature. Both protonema and gametophore stages of gametophyte development were obtained. Also, a stable callus culture was established using hormone-free nutrient medium. The best nutrient medium for development was half-strength Murashige-Skoog medium supplemented with 1.5% sucrose. Auxin treatment enabled some gametophores to develop, but prolonged treatment induced early senescence. Tissues grown on cytokinin did not produce any gametophytes and did not survive prolonged treatment.Sterilna kultura mahovine Pogonatum urnigerum (Polytrichaceae) uspostavljena je iz spora sakupljenih u prirodi. Gajenjem na hranljivoj podlozi bez biljnih hormona iz spora su se razvile protoneme i gametofiti. Uspostavljena je i stabilna kultura kalusa. Ustanovljeno je da je za gajenje ove vrste najbolja hranljiva podloga koja sadrži smanjenu koncentraciju soli i vitamina po Murashige-Skoog-u i 1.5% saharozu. Tretman auksinom nije pospešio razviće gametofita, dok je produženi tretman doveo do postepenog odumiranja protoneme. Tkiva gajena na podlozi koja je sadržala citokinine uopšte nisu produkovala gametofite i nisu preživela produženi tretman ovim hormonom. Ovaj rad predstavlja prvu studiju razvića vrste Pogonatum urnigerum u in vitro kulturi.nul

Bryophytes and heavy metals: a review

Bryophytes, a group of terrestrial plants widely used in biomonitoring, are reviewed for their relation to heavy metals. In the present article, we summarized the knowledge on heavy metals pollution and accumulation effects on bryophytes. Mechanisms of tolerance and resistance are given as well

Effect of ABA treatment on activities of antioxidative enzymes in selected bryophyte species

The effect of the signal molecule and stress phytohormone abscisic acid (ABA) on activities of antioxidant enzymes was tested in three bryophyte species, viz., the liverwort Marchantia polymorpha and the phylogenetically unrelated mosses Physcomitrella patens and Atrichum undulatum. Production of reactive oxygen species increases in plants exposed to both abiotic and biotic stress. Antioxidant enzymes are very effective and usually represent the plant's first line of defence against the cytotoxic effects of these reactive oxygen species. The activities of enzymes of the antioxidative system (POX, CAT, SOD) in the tested bryophyte species are shown to be increased by treatment with lower concentrations of exogenous ABA. Higher concentrations of exogenous ABA did not significantly influence activities of the tested antioxidative enzymes. The obtained results point to possible involvement of ABA as a signal molecule in the first line of defence against stress in all three bryophyte species.Botanica Serbica (2017), 41(1): 11-1

New records and noteworthy data of plants, algae and fungi in SE Europe and adjacent regions, 12

This paper presents new records and noteworthy data on the following taxa in SE Europe and adjacent regions: red algae Hildenbrandia rivularis, saprotrophic fungus Cryptomarasmius corbariensis, lichenised fungi Lecanora stenotropa, Micarea misella and Sticta sylvatica, liverworts Fossombronia caespitiformis and Peltolepis quadrata, mosses Dicranoweisia cirrata and Fissidens exilis, horsetail Equisetum × moorei, gymnosperm Juniperus virginiana, monocots Galanthus reginae-olgae subsp. vernalis and Spiranthes spiralis and dicots Linaria pelisseriana, Parthenocissus quinquefolia, Pilosella rhodopea and Taraxacum erythrospermum are given within SE Europe and adjacent regions

New records and noteworthy data of plants, algae and fungi in SE Europe and adjacent regions, 11

This paper presents new records and noteworthy data on the following taxa in SE Europe and adjacent regions: red algae Sheathia confusa, parasitic fungus Anthracoidea caryophylleae, mycorrhizal fugus Hydnellum caeruleum, bryoparasitic fungus Octospora erzbergeri, liverwort Cephaloziella baumgartneri, mosses Hamatocaulis vernicosus, Streblotrichum convolutum var. commutatum and Ulota crispula, monocots Ophrys bertolonii subsp. bertolonii, Ophrys scolopax subsp. cornuta and Spiranthes spiralis and dicots Androsace hedraeantha, Hieracium mrazii, Ramonda nathaliae and Triglochin palustris are given within SE Europe and adjacent region