摘要:

The female gametophyte ofTaxuswas excised at the mature seed stage and was successfully grownin vitrowithout the embryo. The gametophyte tissue, which had large lipid reserves when placed into culture, showed cell dedifferentiation. In about 6% of cultures, unorganized, crumbly outgrowths were produced. After 2 months, a slow-growing, undifferentiated tissue was isolated. It contained some isolated tracheids, and, in most cells, a rough photosynthetic apparatus was apparent. [Journal translation]

ISSN:0008-4026    

DOI:10.1139/b82-203

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

The study of the growth and metabolism of young plants grown in the presence of salt enables their classification according to their increasing sensitiveness to NaCl:Suaeda maritima(L.) Dum. var.macrocarpaMoq.,Atriplex hortensisL. andPhaseolus vulgarisL. The influence of salinity on the evolution of soluble leaf proteins was compared in the three plants grown on culturing solutions more or less rich in salt. Examination of electrophoregrams emphasizes the qualitative stability of the protein macromolecules. The protenome of the obligate halophyteSuaeda maritimavar.macrocarpais characterised by its richness in high molecular weight proteins. WithAtriplex hortensis, a salt-resistant plant, accumulating Na+in its aerial organs, the salt induces a progressive increase of the synthesis of a high molecular weight proteinaceous fraction. In contrast,Phaseolus vulgaris, a plant very sensitive to NaCl, does not transport Na+into the tissues analyzed. In this species the salt does not induce a detectable change in the soluble proteins. The increased synthesis or the preservation of the high molecular weight proteins in the resistant or halophilic plants could reflect an adaptation mechanism to hypersaline conditions.

ISSN:0008-4026    

DOI:10.1139/b82-204

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

Hymenostylium recurvirostrumvar.insigne(Dix.) Bartr. is reported new to the New World from British Columbia.Hymenostylium recurvirostrumvar.cylindricum(Bartr.) Zander is a new combination. A key to the varieties ofH. recurvirostrumis given.Barbula amplexifolia(Mitt.) Jaeg. is reported new to British Columbia.

ISSN:0008-4026    

DOI:10.1139/b82-205

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

Roots of western hemlock (Tsuga heterophylla) seedlings 1–5+ years old that had established naturally on logs in three states of decay or on mineral soil were compared for numbers and kinds of ectomycorrhizae. Mycobionts colonizing root systems includedCenococcum geophilumFr.,Piloderma croceum(Bres.) Erikss. & Hjorts., and four unidentified fungi distinguished by color and morphology. About half the seedlings surviving the first growing season (2–7 months) were nonmycorrhizal. Nonmycorrhizal seedlings were most frequent on the least decayed logs. However, mycotrophy appeared to be advantageous to hemlock; 1st-year mycorrhizal seedlings had shoots 60% longer and roots 47% longer than 1st-year nonmycorrhizal seedlings. All 2nd-year and older seedlings were mycorrhizal. The ability of western hemlock to survive the first growing season without mycorrhizae may contribute to its success in colonizing decaying logs, which may contain microsites devoid of effective ectomycorrhizal inocula.

ISSN:0008-4026    

DOI:10.1139/b82-206

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

Gametophytes of two populations ofAnemia mexicanaKlotzsch exhibited antheridiogen activity. All gametophytes grown as monospore cultures produced organized meristems and only archegonia, although spore size and days from sowing until germination, meristem organization, and archegonia formation varied. In multispore cultures, gametophytes were either antheridiate or archegoniate, indicating that gametophyte interactions are necessary for antheridia formation. When old media extracts from multispore cultures ofA. mexicanagametophytes were incorporated into new media, precocious antheridia were formed byA. mexicanaandLygodium japonicumbut not byA. phyllitidis, Pteridium aquilinum, orCeratopteris thalictroides. Few antheridia were initiated byA. mexicanagametophytes under red light, suggesting that antheridiogen could not completely overcome a block to antheridium formation. Spores ofA. mexicana, A. phyllitidis, andL. japonicum, but notP. aquilinumandC. thalictroides, germinated in the dark in response to old media extracts incorporated into the basal medium. Thus, antheridiogen activity ofA. mexicanais limited to schizaeaceous species of ferns.

ISSN:0008-4026    

DOI:10.1139/b82-207

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

A study was conducted to determine whether recurrent treatment of wild oat populations with triallate results in increased tolerance of this herbicide. Among several parameters of seedling growth investigated, percentage emergence, seedling survival, and length of the first leaf were found to be most useful in assessing response to this compound. The results revealed a substantial within-population variability for tolerance. Evidence is presented that recurrent herbicide treatment of wild oat populations by the methods commonly used in the control of this weed species in western Canada results in increased tolerance of triallate.

ISSN:0008-4026    

DOI:10.1139/b82-208

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

Spartina alternifloradecomposition was monitored in the high and low salt marsh in litter bags (2-mm mesh). The detritus formed in this process was analyzed at various times for ash-free dry weight (AFDW) (combustion at 550 °C), total carbon (wet combustion to CO2), and total nitrogen (Kjeldahl digestion). A mathematical component model predicting the change of these parameters was developed to explain these data.The first-order decay equationXt = X0 e−ktwas used to explain AFDW and carbon changes. Thekvalues ranged from 0.004 to 0.02 per day for data from the high and low marsh, respectively, for New Jersey. Nitrogen fluxes are described by four functions. Three of these are decay functions which theoretically model (1) loss of soluble nitrogen, (2) loss of recalcitrant nitrogenous plant material, and (3) loss of microbial nitrogen. The fourth is a logistic function which describes the microbial incorportaion of nitrogen into the detritus. Nitrogen and C/N ratio values calculated with these equations simulated values obtained from field data.

ISSN:0008-4026    

DOI:10.1139/b82-209

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

Three anthocyanin polymorphisms inMimulus guttatusDC. have been described and analysed genetically. These involved leaf blotches, calyx dots, and general deposition of anthocyanin. In the case of leaf blotches two plants with sharply contrasting leaf blotches were analysed and it was shown that the blotch phenotype in each is due to the same gene, probably the dominant gene identified in a previous study, here calledL. (The difference between the plants must be ascribed to other complex genetic modifiers.) The presence or absence of calyx dots was shown to be due to a pair of alleles,C(presence) andc(absence). The presence or absence of general anthocyanin deposition in the stems petioles and calyces is controlled by the allelesA(presence) anda(absence). Whereas the expression ofLis less in warm conditions, the expression ofAis enhanced by exposure to the sun.

ISSN:0008-4026    

DOI:10.1139/b82-210

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

Changes in the starch and protein reserves ofAraucaria araucana(Mol.) Koch embryo and megagametophyte tissue during the first 90 h after the start of imbibition have been measured by colorimetric and by chromatographic methods. The starch content (about 30%) of the embryo decreases rapidly until radicle protrusion–germination (40 h) and remains relatively constant (at about 9%) after that. Starch content of the megagametophyte decreases slowly throughout the 90 h. Amylase activity and soluble carbohydrate content of the embryo peak rapidly at 20 h, decline rapidly until germination, and increase slowly thereafter. Total amylase activity of the megagametophyte does not change markedly. Total soluble-protein content of the embryo decreases during the first 20 h and increases thereafter. The embryo protein bodies also disappear during the first 20 h. The hypocotyl enlarges to a bulbous shape and may serve as a secondary protected reserve.

ISSN:0008-4026    

DOI:10.1139/b82-211

出版商:NRC Research Press    

年代:1982

数据来源: NRC

摘要:

Na+–K+and Na+–Ca2+interactions are measured by mineral analysis of germinating plantlets of radish (Raphanus sativusL.) in nutritive solutions enriched in these three elements. With high concentrations of CaCl2, more than 2.5 mM, the absorption of sodium is stimulated especially when there is a high percentage of this element in the external solution. On the other hand, KCl brings about a decrease in the sodium content in the hypocotyl, cotyledons and root; no one organ is affected. Only the uptake of sodium is modified not its transport, which is always proportional to the quantity absorbed. The absorption of calcium and potassium does not evolve in proportion to their external amounts, and the inhibition of accumulation of these elements by sodium is not dependent on the concentration of NaCl. The uptake of calcium is more inhibited than that of potassium which varies with the quantities of KCl and NaCl in the germination medium. Thus, potassium inhibits the uptake of sodium more than sodium inhibits that of potassium. However, whereas the absorption of sodium is only slightly modified by calcium, the absorption of calcium depends highly on the concentration of sodium.

ISSN:0008-4026    

DOI:10.1139/b82-212

出版商:NRC Research Press    

年代:1982

数据来源: NRC