A CYTOLOGICAL STUDY OF ASCOCYBE

1961 ◽  
Vol 39 (7) ◽  
pp. 1605-1607 ◽  
Author(s):  
Charles M. Wilson
Keyword(s):  
Life Cycle ◽  
Chromosome Number ◽  
Cytological Study ◽  
Nuclear Behavior

The nuclear behavior in the life cycle of Ascocybe grovesii is described. The chromosome number is given as six from counts made of chromosomes in the meiotic divisions in the asci. The ascophores are described as diploid, and as a consequence there is no fusion of nuclei in the asci.

NUCLEAR PHENOMENA IN THE LIFE CYCLE OF GANODERMA LUCIDUM (LEYSS. EX FR.) KARST.

1959 ◽  
Vol 37 (1) ◽  
pp. 59-64 ◽  
Author(s):  
Anjali Sarkar
Keyword(s):  
Life Cycle ◽  
Chromosome Number ◽  
Ganoderma Lucidum ◽  
West Bengal ◽  
The Other ◽  
Multinucleate Cells ◽  
Nuclear Behavior

Nuclear behavior in the life cycle of Ganoderma lucidum (Leyss. ex Fr.) Karst., a common polypore in West Bengal, India, has been studied. Each young basidium is binucleate and the nuclei soon fuse to form a syncaryon which undergoes three successive divisions, of which the first is reductional, to produce eight daughter nuclei. Four nuclei pass into the four spores, one into each, and the other four, remaining within the basidium, finally degenerate. Thus at first each basidiospore contains one nucleus which may or may not divide further. On germination, the spores give rise to primary mycelia with uninucleate or multinucleate cells. Secondary mycelia, formed by the union of two compatible primary mycelia, have nodose-septate hyphae in which most of the cells are dikaryotic although cells with more than two nuclei are not uncommon.The chromosome number, counted from metaphasic plates, has been found to be 10 = 2n.

The cytology and development of Preussia flanaganii sp. nov.

1970 ◽  
Vol 48 (1) ◽  
pp. 163-166 ◽  
Author(s):  
Brendan V. Boylan
Keyword(s):  
Life Cycle ◽  
Chromosome Number ◽  
Hyphal Fusion ◽  
Nuclear Cycle ◽  
Fusion Site

The life cycle of Preussia flanaganii Boylan sp. nov. is demonstrated. The ascocarp develops as a result of hyphal fusion and the subsequent proliferation of pseudoparenchyma at the fusion site. The ascocarp is uniloculate or multiloculate and non-ostiolate. The fungus has no known asexual phase and is homothallic. The nuclear cycle in the asci follows a pattern similar to that found in other Euascomycetes. The chromosome number is about 14.

Nuclear behavior and clarification of the spore stages of Uromyces koae

1981 ◽  
Vol 59 (5) ◽  
pp. 939-946 ◽  
Author(s):  
Donald E. Gardner
Keyword(s):  
Life Cycle ◽  
Meiotic Division ◽  
Germ Tube ◽  
Nuclear Staining ◽  
Diploid Nucleus ◽  
Spore Type ◽  
Acacia Koa ◽  
Nuclear Behavior ◽  
Germ Tubes

Recent observations showed that Uromyces koae Arthur in Stevens teliospores did not produce typical basidia or basidio-spores. The present study reveals that teliospores produced long germ tubes that are differentiated into wide proximal and narrow distal portions separated by a vesiclelike swelling. One or two extensive branches, each morphologically resembling the main tube, developed from individual germ tube cells. Nuclear staining revealed a single, presumably diploid nucleus in mature teliospores. One or more probable mitotic divisions in the main germ tube provided a diploid nucleus for each branch and for the main tube itself. Meiotic division of each nucleus produced a series of four smaller nuclei in the narrow portion of each branch and the main tube. The germ tubes may be modified basidia and serve as infectious hyphae in place of basidiospores.A formerly undescribed spore type associated with the teliospores is recognized as uredinial. This investigation shows that the life cycle of U. koae probably consists of four distinct stages, each on Acacia koa: the spermatial associated with the aecial on hypertrophied shoots, and the uredinial and telial together in discrete leaf pustules.

The biosystematics of the genus Lotus (Leguminosae) in Canada. II. Numerical chemotaxonomy

1968 ◽  
Vol 46 (5) ◽  
pp. 585-589 ◽  
Author(s):  
William F. Grant ◽  
Ilse I. Zandstra
Keyword(s):  
Chromosome Number ◽  
Thin Layer ◽  
Native Species ◽  
Cytological Study ◽  
Diploid Species ◽  
Basic Chromosome Number ◽  
Chromatographic Study ◽  
Chemical Identification ◽  
Basic Chromosome ◽  
Fluorescent Compounds

A thin-layer chromatographic study of fluorescent compounds present in native (L. denticulatus, L. formosissimus, L. micranthus, L. pinnatus, L. purshianus) and introduced (L. corniculatus, L. krylovii, L.pedunculatus, L. tenuis) Canadian species of Lotus has been carried out and relationships of the species have been determined on the basis of the coefficients of association of these compounds. Chemical identification of the compounds was not attempted, but test reagents indicated a number to be phenolics. The analysis supported the general taxonomic relationships of the species based on a morphological and cytological study. Of the native species, L. pinnatus and L. formosissimus were the most closely related, with a coefficient of association of 83.33. Lotus denticulatus, the only native species with a chromosome number of n = 6, in general showed lower coefficients of association with the n = 7 species. Of the introduced species, all of which belong to the L. corniculatus group with a basic chromosome number of 6, L. krylovii and L. tenuis had the highest coefficient of association, 75.86. Based on their coefficients of association, both of these diploid species were more closely related to the tetraploid L. corniculatus than to the diploid L. pedunculatus.

COCCIDIOIDES IMMITIS: CYTOLOGICAL STUDY ON THE FORMATION OF THE ARTHROSPORES

1969 ◽  
Vol 11 (1) ◽  
pp. 43-53 ◽  
Author(s):  
Kyung Joo Kwon-Ciiung
Keyword(s):  
Chromosome Number ◽  
Nuclear Division ◽  
Cytological Study ◽  
Ring Stage ◽  
Coccidioides Immitis ◽  
Active Growth ◽  
Spindle Apparatus ◽  
Relationship Of ◽  
The Relationship

Somatic nuclear division and the manner of arthrospore formation in saprophytic phase of Coccidioides immitis have been studied. Two distinct nuclear cycles, one occurring during the active growth in young hyphae and another occurring in old thin hyphae or during arthrospore formation, were observed. The first cycle consisted of several stages starting from round resting nuclei → ring stage → V stage → and filaments which divide longitudinally. The two daughter nuclear filaments reorganize into round nuclei. The second cycle is more simple than the first. The round resting nuclei become elongated and constricted at the middle, dividing vertically. The chromosome number appears to be 3. The metaphase plares or spindle apparatus were not seen.The fertile hyphae develop septa not basipetally but synchronously. Alternate cells, after being thus delimited, increase in size and in thickness of wall becoming spores while the intervening cells gradually lose cytoplasm. The nuclei remain, without cytoplasm, in the intervening cells until the adjacent spores are completely matured. The spores are released by fragmentation of the walls of the sterile segments. The relationship of C. immitis to the members of Gymnoascaceae has been discussed.

A new chromosome number in Arctostaphylos uva-ursi

1981 ◽  
Vol 59 (2) ◽  
pp. 272-273 ◽  
Author(s):  
Thomas J. Rosatti
Keyword(s):  
New York ◽  
Chromosome Number ◽  
Cytological Study ◽  
Long Island ◽  
Physiological Tolerance

Populations resembling Arctostaphylos uva-ursi (L.) Spreng. var. coactilis Fernald and MacBride growing on Long Island, New York, U.S.A., provided material for cytological study which resulted in the discovery of a new chromosome number for the species, 2n = 78. These plants differ from the most common expression of this variety in having more linear leaves, a condition that may be associated with a physiological tolerance for relatively high levels of salt in the substratum.

Ultrastructural aspects of sporogenesis in the apogamous fern Dryopteris borreri

1983 ◽  
Vol 63 (1) ◽  
pp. 125-134
Author(s):  
E. Sheffield ◽  
S. Laird ◽  
P.R. Bell
Keyword(s):  
Life Cycle ◽  
Cell Division ◽  
Chromosome Number ◽  
Plant Cell ◽  
Major Part ◽  
The Novel ◽  
Wall Ingrowths ◽  
Plant Cell Division ◽  
Discrete Band ◽  
Meiosis I

The events that accompany sporogenesis in the apogamous fern Dryopteris borreri parallel those seen in sexually reproducing ferns. Organelles dedifferentiate and redifferentiate, and form a discrete band across the equator of dyads; nuclear vacuoles and lipid spherosomes appear during prophase, and the major part of the ribosome population is removed and subsequently replaced during meiosis. Similar events have been found to occur during sporogenesis in mosses, gymnosperms and angiosperms, and therefore characteristic of the meiotic transition from sporophyte to gametophyte, even in the absence of a transition from diplophase to haplophase. The novel aspects of meiosis in D. borreri are largely those connected with the restitution event that precedes meiosis I and serves to maintain the sporophytic chromosome number throughout the life cycle of this fern. Pre-meiotic cells are regularly found to be cleaved by annular wall ingrowths, which traverse the cytoplasm but not the nuclei. The significance of these ingrowths in relation to theories concerning apogamy and plant cell division are discussed.

Sign in / Sign up

Export Citation Format

Share Document