Download or read book Meiosis in Certain Interspecific Hybrids in Crepis and Its Bearing on Taxonomic Relationship Classic Reprint written by Ernest Brown Babcock and published by Forgotten Books. This book was released on 2017-11-07 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Meiosis in Certain Interspecific Hybrids in Crepis and Its Bearing on Taxonomic Relationship Most crepis species are excellent subjects for cytological research be cause of their generally large and morphologically distinct chromo somes. The genus includes three subgenera, in each of which numerous representative species have been studied with reference to comparative morphology, geographic distribution, and chromosome relations (bab cock and Cameron, 1934; Babcock, Cytogenetic studies on several hybrids between species in the same subgenus and in difierent subgenera have exhibited phenomena that throw light on problems of taxonomy, phylogeny, and evolution (babcock and N avashin, The present investigation was undertaken with the hope of contributing further evi dence on some of these problems. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
Download or read book Meiosis in Certain Interspecific Hybrids in Crepis and Its Bearing on Taxonomic Relationship written by Ernest Brown Babcock and published by . This book was released on 1936 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Meiosis in Certain Interspecific Hybrids in Crepis and Its Bearing on Taxonomic Relationship P6 12 written by E B (Ernest Brown) 1877-1 Babcock and published by Hassell Street Press. This book was released on 2021-09-10 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. To ensure a quality reading experience, this work has been proofread and republished using a format that seamlessly blends the original graphical elements with text in an easy-to-read typeface. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Download or read book Meiosis in Two Species and Three Hybrids of Crepis and Its Bearing on Taxonomic Relationship Classic Reprint written by Ernest Brown Babcock and published by Forgotten Books. This book was released on 2017-10-27 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Meiosis in Two Species and Three Hybrids of Crepis and Its Bearing on Taxonomic Relationship The buds are put in the Carnoy fixative and, as for Crepis, the tips of the involucral scales are removed in order to facilitate pene tration of the fixative between the florets. The buds remain in the first fixative from three to ten minutes, when they are changed into Navashin's formalin-chromic-acetic acid. Carnoy's fluid seems to prepare the way through the tissue for the second fixative, but in the Short time of application it does not dehydrate or collapse the tissue. Kihara (1924) describes a combination carnoy-flemming's fluid which is based on the same principle as the combination here described. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
Download or read book Meiosis in Two Species and Three Hybrids of Crepis and Its Bearing on Taxonomic Relationship written by Ernest Brown Babcock and published by . This book was released on 1929 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Meiosis in Two Species and Three Hybrids of Crepis and Its Bearing on Taxonomic Relationship written by Ernest B. Babcock and published by . This book was released on 1919 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Meiosis in Two Species and Three Hybrids of Crepis and Its Bearing on Taxonomic Relationship P2 15 written by E B (Ernest Brown) 1877-1 Babcock and published by Hassell Street Press. This book was released on 2021-09-10 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. To ensure a quality reading experience, this work has been proofread and republished using a format that seamlessly blends the original graphical elements with text in an easy-to-read typeface. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Download or read book Meiosis in Two Species and Three Hybrids of Crepis and Its Bearing on Taxonomic Relationship by E B Babcock and J Clauser written by E. B. Babcock and published by . This book was released on 1929 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Meiosis in Certain Interspecific Hybrids in Crefis a Nol Its Beorino in Toxo Nomic Relationship written by E.B. Bobcock and published by . This book was released on with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Distant Hybridization of Crop Plants written by G. Kalloo and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wild taxa are invaluable sources of resistance to diseases, insects/ pests, nematodes, temperature extremes, salinity and alkalinity stresses, and also of nutritional quality; adaptation; genetic diversity and new species. Utilization of wild relatives of a crop depends largely upon its crossability relations with cultivated varieties. Sev eral wild species are not crossable with the commercial cultivars due to various isolation barriers. Furthermore, in a few cases, hybridiza tion is possible only in one direction and reciprocal crosses are not successful, thus depriving the utilization of desired cytoplasm of many species. However, techniques have been developed to over come many barriers and hybrid plants are produced. New crop species have been developed by overcoming the F 1 sterility and producing amphidiploids and such crops are commercially being grown in the field. The segregation pattern ofF 1 hybrids produced by distant hybridization in segregating generations are different from the intervarietal hybrids. In former cases, generally, unidirectional segregation takes place in early generations and accordingly, selec tion procedures are adopted. In most of the cases, backcross or modified backcross methods have been followed to utilize wild species, and thus numerous types of resistance and other economical attributes have been transferred in the recurrent parents. Protoplast fusion has been amply demonstrated in a number of cases where sexual hybridization was not possible and, as a result, hybrids have been produced.
Download or read book Cytogenetics written by J. Schulz-Schaeffer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 1961 the author has taught a course in Cytogenetics at Montana State University. Undergraduate and graduate stu dents of Biology, Chemistry, Microbiology, Animal and Range Science, Plant and Soil Science, Plant Pathology and Veterinary Science are enrolled. Therefore, the subject matter has been pre sented in an integrated way to correlate it with these diverse disciplines. This book has been prepared as a text for this course. The most recent Cytogenetics text was published in 1972, and rapidly developing research in this field makes a new one urgently needed. This book includes many aspects of Cytogenetics and related fields and is written for the college student as well as for the researcher. It is recommended that the student should have taken preparatory courses in Principles of Genetics and Cytol ogy. The content is more than is usually taught during one quar ter of an academic year, thus allowing an instructor to choose what he or she would like to present to a class. This approach also allows the researcher to obtain a broad exposure to this field of biology. References are generously supplied to stimulate orig inal reading on the subject and to give access to valuable sources. The detailed index is intended to be of special assistance to researchers.
Download or read book Genetic control of self incompatibility and reproductive development in flowering plants written by Elizabeth G. Williams and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 545 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plant reproductive biology has undergone a revolution during the past five years, with the cloning, sequencing and localization of the genes important in reproduction. These advantages in plant molecular biology have led to exciting applications in plant biotechnology, including the genetic engineering of male sterility and other reproductive processes. This book presents an interesting and contemporary account of these new developments from the scientists in whose laboratories they have been made. The chapters focus on two areas: the molecular biology of self-incompatibility, which is the system of self-recognition controlled by the S-gene and related genes; and the cellular and molecular biology of pollen development and genetic dissection of male sterility. Some chapters feature Arabidopsis, with its unique genetic system. Reproduction is vital for seed production in crop plants, and this book presents new approaches to manipulate plant breeding systems for the 21st century.
Download or read book The Meiotic System written by Bernard John and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction When the study of heredity and variation first came to be treated as a scientific subject-and this, one must remember, was only just over a hundred years ago-there was an unfortunate separation between the disciplines of cytology and experimental breeding. This separation was based partly on a lack of understanding and partly on a lack of the desire to understand. Even WILLIAM BATESON, the first apostle of mendelism in England, had a blind spot for cytology and for many years dogmatically refused to believe that MENDEL'S determinants were transmitted and distributed by the chromosomes. This separation between cytology and experimental breeding is one which persists, in a measure, even today, simply because there are two quite different, though complementary, techniques available for the study of heredity and variation. On the one hand, one can study directly the structure and behaviour of the actual vehicles which transmit the genetic determinants from one generation to the next. This is the method employed by those who study genetics through a microscope. The alternative method is that used by the experimental breeder who, in default of being able to watch the hereditary factors segregate from each other directly, is obliged to examine the constitution of the germ cells indirectly by sampling, and usually at random, the products of a controlled mating.
Download or read book Pollination Mechanisms Reproduction and Plant Breeding written by R. Frankel and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: view than its own proper males should fecundate each blossom." ANDREW KNIGHT Philosophical Transactions, 1799 Pollination mechanisms and reproduction have a decisive bearing upon rational procedures in plant breeding and crop production. This book intends to furnish' under one cover an integrated botanical, genetical and breeding-methodologi cal treatment of the reproductive biology of spermatophytes mainly angiosperms; it is based on an advanced topical course in plant breeding taught at the Hebrew University of Jerusa lem. We have tried to present a coverage which is concise, but as comprehensive as possible, of the pollination mechanism and modes of reproduction of higher plants, and to illustrate topics, whenever practicable, by examples from cultivated plants. Nevertheless, some relevant publications may have escaped our attention or may not be mentioned because of various limitations. The book is organized into three parts. The first part starts with an evaluation of the significance of the different pollination mechanisms for plant breeding and crop produc tion, describes modes of reproduction in higher plants and discusses ecology and dynamics of pollination. The second part is devoted to crops propagated by self pollination and describes specific breeding procedures for such crops. The third part details sexual reproduction in higher plants and handles three mechanisms involved in the prevention of self pollination and their utilization in plant breeding: sex expres sion, incompatibility, and male sterility.
Download or read book Molecular Plant Taxonomy written by Pascale Besse and published by Humana. This book was released on 2014-01-11 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plant taxonomy is an ancient discipline facing new challenges with the current availability of a vast array of molecular approaches which allow reliable genealogy-based classifications. Although the primary focus of plant taxonomy is on the delimitation of species, molecular approaches also provide a better understanding of evolutionary processes, a particularly important issue for some taxonomic complex groups. Molecular Plant Taxonomy: Methods and Protocols describes laboratory protocols based on the use of nucleic acids and chromosomes for plant taxonomy, as well as guidelines for phylogenetic analysis of molecular data. Experts in the field also contribute review and application chapters that will encourage the reader to develop an integrative taxonomy approach, combining nucleic acid and cytogenetic data together with other crucial information (taxonomy, morphology, anatomy, ecology, reproductive biology, biogeography, paleobotany), which will help not only to best circumvent species delimitation but also to resolve the evolutionary processes in play. Written in the successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and easily accessible, Molecular Plant Taxonomy: Methods and Protocols seeks to provide conceptual as well as technical guidelines to plant taxonomists and geneticists.
Download or read book Biotechnology and Ecology of Pollen written by David L. Mulcahy and published by Springer. This book was released on 2011-11-11 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Recognition of the Forgotten Generation D. L. MULCAHyl Pollen was long believed to serve primarily a single function, that of delivering male gametes to the egge A secondary and generally overlooked value of pollen is that it serves to block the transmission of many defective alleles and gene combinations into the next generation. This latter function comes about simply because pollen tubes carrying defective haploid genotypes frequently fail to complete growth through the entire length of the style. However, the beneficial consequences of this pollen selection are diluted by the fact that the same deleterious genotypes are often transmitted through the egg at strictly mendelian frequencies (Khush, 1973). Gene expression in the pollen might thus at least appear to be a phenomenon of trivial consequence. Indeed, Heslop-Harrison (1979) rightly termed the gametophytic portion of the angiosperm life cycle, the "forgotten generation." This neglect, however, came about despite subtle but constant indications that pollen is the site of intense gene activity and selection. For example, Mok and Peloquin (1975) demonstrated that relatively heterozygous diploid pollen shows heterotic characteristics whereas relatively homozygous diploid pOllen does not. This was proof positive that genes are expressed (that is, transcribed and translated) in the pollen. 1 Department of Botany, University of Massachusetts Amherst, MA 01003, USA viii However, the implications for pollen biology of even this recent and well known study were not widely recognized.
Download or read book Chromosomes Today written by N. Henriquez-Gil and published by Springer Science & Business Media. This book was released on 1996-12-31 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chromosomes Today Volume 12 records the plenary proceedings of the 12th triennial International Chromosone Conference, presenting an overview of the current concerns in the developing studies of animal, plant and human cytogenetics. As well as giving an accurate historical record of the achievements in chromosome studies, this important series points the way forword, emphasizing the areas in which new developments will take place. Volume 12 explores the complete integration of molecular biology and cytogenetics, evaluating the concensus of the world's cytogeneticists concerning the nature and activities of the chromosome.It reinforces our view of the chromosome as the genetic organelle whose structure, behaviour and modification underlie our modern concept ofeukaryote genetics.
