Cytogenetics of forest tree species

Type :

Presentation

Pages :

9 pages

Format :

.doc

Published date :

11/25/2008

Category :

Political science

Sub category :

Ecology & environment

Oboulo.com selection criteria

$ 18.95 Add to cart

Summary :

Introduction.
1. Plant breeding.
2. Cytogenetic investigations of forest tree species.
3. The main interest in forest tree cytogenetics in the early 1900's.
Cell division and chromosomes.
1. Cell division - nuclear (karyokinesis) and cytoplasmic (cytokinesis) division.
2. Mitosis.
3. Meiosis.
4. The interkinesis stage.
Variation in chromosome numbers.
1. Polyploidy.
2. Eneuploidy.
3. Basic chromosome number.
Slide preparation methodology.
1. Uniform chromosome staining.
2. Karyotype analysis.
3. Banding methods.
Applications of cytogenetics to basic genetic research in forest trees.
Applications of cytogenetics to tree improvement.
Conclusion.

Abstract

The discipline of cytogenetics was ﬁrst deﬁned by Sutton in 1903, as a ﬁeld of investigation which developed from the separate sciences of genetics and cytology. It is concerned with studies on the correlation of genetic and cytological (especially chromosomal) features characterizing a particular genetic system under investigation. With respect to forest trees, cytogenetic studies have generally been limited to chromosome studies, on the number, appearance, and behavior of chromosomes during mitosis and meiosis, chromosomal and karyotypic evolution, and the role of chromosomes in the transmission and recombination of genes. Plant breeding can be traced to the ancient Babylonians, but a clear understanding of genetics has its beginning in the nineteenth century with Mendel's hybridization experiments and their subsequent rediscovery by de Vries, Correns, and von Tschermack in 1900. Cytology required the invention of the microscope, and began when Robert Hook observed cork cells in 1665. Early scientists studied cell structure, organelles, and division. Nageli ﬁrst described chromosomes as visual bodies during cell division in 1844, and Fleming in 1882 described the complete process of mitotic nuclear division. However, it was not until the independent observations of Sutton and Boveri that chromosomes were ﬁrst linked with the emerging ﬁeld of genetics.