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Studies on the bryophyte flora of the Southern Ocean islands and in the Antarctic are briefly reviewed and the current state of knowledge of the moss flora of Îles Kerguelen is discussed. Macrocoma tenue (Hook. & Grev.) Vitt is recorded from the Îles Kerguelen archipelago and this constitutes the first record of the genus Macrocoma (Müll. Hal.) Grout from the Subantarctic. The local plants of the species are characterized and illustrated and their ecology is discussed. Global distribution of M. tenue is reviewed and mapped. It is suggested that the type subspecies of M. tenue is a Gondwanan relictual taxon, which could have evolved on this supercontinent prior to its break-up and, subsequently, it reached Îles Kerguelen where it survived during the Pleistocene glacial epoch.

The title compound, C14H15NO5, was obtained from the reaction of acetanilide with dimethyl acetylenedicarboxylate in the presence of potassium carbonate. The C=C double bond adopts an E configuration and the geometry around the amide N atom is almost planar rather than pyramidal (mean deviation of 0.0032 Å from the C3N plane). The packing of the molecules in the crystal structure is stabilized by intermolecular C—H...O hydrogen bonds.

Studies on the bryophyte flora of the Southern Ocean islands and in the Antarctic are briefly reviewed and the current state of knowledge of the moss flora of Îles Kerguelen is discussed. Macrocoma tenue (Hook. & Grev.) Vitt is recorded from the Îles Kerguelen archipelago and this constitutes the first record of the genus Macrocoma (Müll. Hal.) Grout from the Subantarctic. The local plants of the species are characterized and illustrated and their ecology is discussed. Global distribution of M. tenue is reviewed and mapped. It is suggested that the type subspecies of M. tenue is a Gondwanan relictual taxon, which could have evolved on this supercontinent prior to its break-up and, subsequently, it reached Îles Kerguelen where it survived during the Pleistocene glacial epoch. [ABSTRACT FROM AUTHOR]

Using 76 presence-only data, altitude, percent tree cover and 11 bioclimatic variables, we modeled the geographical distribution of Macromitrium japonicum in China with an aid of a maximum entropy algorithm modeling program (MaxEnt). We found habitats suitable for M. japonicum in the major mountains in southeastern, southern, and southwestern China, and also in the Changbai Mountains, Taihang Mountains, Yanshan Mountains, Tainwan and Hainan Island. With increasing percent of tree cover, mean temperatures in the driest quarter, the warmest quarter and the coldest quarter, and with decreasing annual temperature range and mean diurnal temperature range, habitat suitability for M. japonicum increases. The MaxEnt model also indicated that areas with precipitation of the wettest month being 300 mm, and precipitation of the warmest quarter being 500-600 mm are favourable for M. japonicum. It also favours lower altitudes (0-1000 m a.s.l.), while with increasing altitude (from 1000 to 6000 m a.s.l.), habitat suitability decreases. Habitat suitability for M. japonicum firstly increases rapidly with increasing precipitation in the driest month and the coldest quarter at lower altitudes, and then slightly increases after the factors exceed a certain threshold value. [ABSTRACT FROM AUTHOR]

Three species of Macromitrium (Bryopsida, Orthotrichaceae), namely M. blumei Nees ex Schwagr., M. cuspidatum Hampe, and M. turgidum Dixon are reported for the first time from China (Hainan and Tibet). Studies of their types and morphological similar species suggest that M. turgidum Dixon var. laeve Dixon is conspecific with M. turgidum Dixon. A key to 27 Chinese species of Macromitrium with their distribution range is presented. For Chinese Macromitrium, east Asiatic element, element endemic to China, and tropical Asian element account for 37.04%, 33.33% and 22.22%, respectively. 62.96% species of Chinese Macromitrium have a tropical distribution pattern. China has a close relationship with Japan and tropical Asia in the flora of Macromitirum. [ABSTRACT FROM AUTHOR]

DNA C-values might be one of important indices in the evaluation of angiospermous invasiveness. To test this viewpoint, we compared DNA 1C-values and basic genome sizes in 3,676 angiosperms. The results suggest that: (1) the two nuclear values vary greatly among different groups, e.g., significantly higher in herbs than in trees, in monocots than in dicots, in perennials than in non-perennials; (2) the two nuclear values both have significant effects on plant invasiveness, especially in herbs, dicots, monocots, perennials, non-perennials, diploids, polyploids, Compositae, and Poaceae, while not significant in trees and Fabaceae. Similar to weeds, the two values in crops are low, which suggests that crops may commonly hold higher invasive potential; (3) to evaluate the invasiveness of a given species, the information about ploidy level is necessary, and for polyploids, basic genome sizes are more reliable. For the results suggest that the selection favors polyploids in weeds at least partly because of the downsizing of basic genome size along with polyploidization. [ABSTRACT FROM AUTHOR]

In China, fireweed ( Crassocephalum crepioides) is listed as an invasive plant that is also cultivated as a vegetable. To gain a clearer understanding of its invasiveness and rapid spread, we evaluated its seed dispersal ability, and the influences of light, temperature, pH, NaCl stress, moisture content, and storage periods on its seed germination. Its seed dispersal ability is limited. The seed germination of fireweed is inhibited by darkness, temperatures <10°C or >35°C, and a NaCl solution with a concentration >0.15 mol L−1. The optimal conditions under which nearly all the seeds could germinate are light, with temperatures from 20 to 30°C, and a neutral soil with 40% moisture content. The seeds of fireweed have no apparent dormancy and retain a high viability after room storage for 10 months. Fireweed only has a moderate invasive capacity and its wide distribution in China possibly correlates with its cultivation. [ABSTRACT FROM AUTHOR]

Macromitrium cavaleriei Cardot & Thér. in Thér. is a little known Chinese moss of the family Orthotrichaceae. The species, which, forms dense mats with creeping stems, varies much in its branch leaf shape and in the laminal cell papillosity of the branch and perichaetial leaves. In the present paper, Macromitrium cavaleriei is re-evaluated taxonomically, including the new synonymizations of M. gebaueri Broth., M. sinense E. B. Bartram, M. syntrichophyllum Thér. & P. de la Varde, and M. syntrichophyllum var. longisetum Thér. & Reimers from China. The synonymizations extend the distribution of M. cavaleriei from Guizhou to 15 provinces and one municipality, mainly in the area to the South of the Yangtze River, Southwest China, and Taiwan. Additionally, M. cavaleriei is reported as new to the moss flora of Japan. [ABSTRACT FROM AUTHOR]

The terrestrial mosses Hypnum hamulosum and Brachythecium brotheri, which could live in water under experimental conditions, were treated with Cd2+ at 0, 20, 50, 100, 150, and 200 mg·L-1, and Cr3+ at 0, 10, 20, 30, 50, and 100 mg·L-1. The Cd2+ and Cr3+ contents in H. hamulosum and B. brotheri were measured by ICP-AES after they had been submerged in the treatment solution for 7, 14, 21, and 28 days. The results showed: (1) Both moss species have a high ability in absorb Cd and Cr. (2) With the increase of Cd2+ (or Cr3+) concentration in the culture solution, the Cd (or Cr) contents both in H. hamulosum and B. brotheri increased linearly (3) With the extension of the treatment time, their Cd and Cr content increased logarithmically. (4) Hyphnum hamulosum and B. brotheri differ in their ability to absorb Cd2+ and Cr3+; the former has a higher ability to absorb Cd2+, but lower ability to absorb Cr3+ than the latter. [ABSTRACT FROM AUTHOR]