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Developmental pathways from isolated protoplasts were investigated with the moss Funaria hygrometrica, the liverwort Anthoceros crispulus, and the fern Anogramma leptophylla. Gametophytic protoplasts regenerated gametophytes. Apospory was obtained with sporophytic protoplasts of the moss and the fern. The archegoniates also grew in interdivisional co-cultures with solanaceous species. 相似文献
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Katie J. Field Jeffrey G. Duckett Duncan D. Cameron Silvia Pressel 《Annals of botany》2015,115(6):915-922
Background and Aims Following the consensus view for unitary origin and conserved function of stomata across over 400 million years of land plant evolution, stomatal abundance has been widely used to reconstruct palaeo-atmospheric environments. However, the responsiveness of stomata in mosses and hornworts, the most basal stomate lineages of extant land plants, has received relatively little attention. This study aimed to redress this imbalance and provide the first direct evidence of bryophyte stomatal responsiveness to atmospheric CO2.Methods A selection of hornwort (Anthoceros punctatus, Phaeoceros laevis) and moss (Polytrichum juniperinum, Mnium hornum, Funaria hygrometrica) sporophytes with contrasting stomatal morphologies were grown under different atmospheric CO2 concentrations ([CO2]) representing both modern (440 p.p.m. CO2) and ancient (1500 p.p.m. CO2) atmospheres. Upon sporophyte maturation, stomata from each bryophyte species were imaged, measured and quantified.Key Results Densities and dimensions were unaffected by changes in [CO2], other than a slight increase in stomatal density in Funaria and abnormalities in Polytrichum stomata under elevated [CO2].Conclusions The changes to stomata in Funaria and Polytrichum are attributed to differential growth of the sporophytes rather than stomata-specific responses. The absence of responses to changes in [CO2] in bryophytes is in line with findings previously reported in other early lineages of vascular plants. These findings strengthen the hypothesis of an incremental acquisition of stomatal regulatory processes through land plant evolution and urge considerable caution in using stomatal densities as proxies for paleo-atmospheric CO2 concentrations. 相似文献
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A cytokinin was isolated from the culture medium of callus cells of the moss hybridFunaria hygrometrica (L.) Sibth xPhyscomitrium piriforme Brid. The purification procedure included ethyl-acetate extraction, silver-salt precipitation, crystallization as picrate, and ion exchange chromatography. The structure of the cytokinin was confirmed as N6–(2-isopentenyl)adenine by means of gas chromatography and mass spectrometry. The concentration of the compound in the culture medium was determined at ca. 10-6 M.Abbreviation 2iP
N6–(2-isopentenyl) adenine 相似文献
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Abstract The relationship between environmental stresses and the genome was investigated by examining the behaviour of repetitive DNA in response to lead or cadmium in two Bryophytes, differing from a physiological and an ecological point of view, namely the aquatic moss L. riparium and the terricolous moss F. hygrometrica. Using different experimental approaches, a direct relationship was shown to exist in these two mosses between the metal-induced stress and repetitive DNA. In fact, in both organisms, metal treatment was accompanied by a selective amplification of some GC-rich repetitive DNA sequences forming peculiar agglomerates inside the nucleus; this amplification is quantitatively proportional to the time of exposure of the plants to the metals and stops upon removal of the metal from the culture medium. Results show that ribosomal DNA sequences are involved in this metal-induced repetitive DNA agglomerate formation, although they are not the only repetitive sequences present within the heterochromatic DNA agglomerates. The plasticity of the genome of the Bryophytes in response to external stimuli, and the fact that repetitive DNA is involved in this plasticity are discussed. 相似文献
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《Journal of bryology》2013,35(2):108-109
AbstractBryophytes usually have anti-feeding properties to defend against microbial and herbivore attack; however, the consumption of Haplocladium microphyllum (Hedw.) Broth. capsules by Agrotis sp. larvae is rather common in Shanghai in the spring. To test whether H. microphyllum is the only moss eaten, and why the gametophytes of H. microphyllum are not eaten, a series of quantitative experiments were carried out to understand the feeding habits of Agrotis larvae on the given moss materials at three growth stages of larval life. The results show that the larvae can feed on the capsules of six moss species to different degrees: Funaria hygrometrica Hedw., H. microphyllum, Physcomitrium sphaericum (C.F.Ludw. ex Schkuhr) Brid., Trematodon longicollis Michx., Ditrichum pallidum (Hedw.) Hampe, and Pogonatum inflexum (Lindb.) Sande Lac. The capsules of the first four species were grazed heavily by the larvae, compared with limited consumption of the latter two (D. pallidum and P. inflexum), which even induced a high mortality rate among the larvae. With the growth of the larval instar, the daily demand for moss capsules by the larvae increases gradually. The lipid content of the capsules may play an important role when the larva selects its feeding target. 相似文献
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