Dna Based Markers In Plants

The double helix architecture of DNA was elucidated in 1953. Twenty years later, in 1973, the discovery of restriction enzymes helped to create recombinant DNA molecules in vitro. The implications of these powerful and novel methods of molecular biology, and their potential in the genetic manipulation and improvement of microbes, plants and animals, became increasingly evident, and led to the birth of modern biotechnology. The first transgenic plants in which a bacterial gene had been stably integrated were produced in 1983, and by 1993 transgenic plants had been produced in all major crop species, including the cereals and the legumes. These remarkable achievements have resulted in the production of crops that are resistant to potent but environmentally safe herbicides, or to viral pathogens and insect pests. In other instances genes have been introduced that delay fruit ripening, or increase starch content, or cause male sterility. Most of these manipulations are based on the introduction of a single gene - generally of bacterial origin - that regulates an important monogenic trait, into the crop of choice. Many of the engineered crops are now under field trials and are expected to be commercially produced within the next few years. The early successes in plant biotechnology led to the realization that further molecular improvement of plants will require a thorough understanding of the molecular basis of plant development, and the identification and character ization of genes that regulate agronomically important multi genic traits.

With the new techniques described in this volume, a new gene can be placed on the linkage map within only a few days. Leading researchers have updated the earlier edition to include the latest versions of DNA-based marker maps for a variety of important crops.

Molecular Markers in Plants surveys an array of technologies used in the molecular analysis of plants. The role molecular markers play in plant improvement has grown significantly as DNA sequencing and high-throughput technologies have matured. This timely review of technologies and techniques will provide readers with a useful resource on the latest molecular technologies. Molecular Markers in Plants not only reviews past achievements, but also catalogs recent advances and looks forward towards the future application of molecular technologies in plant improvement. Opening chapters look at the development of molecular technologies. Subsequent chapters look at a wide range of applications for the use of these advances in fields as diverse as plant breeding, production, biosecurity, and conservation. The final chapters look forward toward future developments in the field. Looking broadly at the field of molecular technologies, Molecular Markers in Plants will be an essential addition to the library of every researcher, institution, and company working in the field of plant improvement.

Until very recently genetic maps of higher plants were based almost entirely on morphological and biochemical traits. These maps are rapidly being replaced and/or supplemented with DNA-based marker maps based on the use of powerful new molecular techniques. The new high precision maps can be developed with comparative ease and rapidity. They have a much higher density of markers, which allows revelation of more and more restricted segments of the genome. One of the many revolutionary aspects of this technology is that linkage between molecular markers and traits of interest often can be detected in a single cross. The ability to hybridize probe after probe to the DNA of the same individuals of a segregating population allows one to pursue the analysis until linkage becomes evident. With morphological and biochemical markers used previously, a separate cross was required to test linkage with each new marker. It was seldom that more than three markers could be tested for linkage with the trait of interest in a single cross because of viability problems. With the new techniques described in this volume, a new gene could be placed on the linkage map within a few days instead of the much longer time required with the previous techniques. In this book, a group of leading researchers provide background information and the latest versions of DNA-based marker maps for a variety of important crops. These maps illustrate the state of the art today. The progress made during the past five years has been truly phenomenal.

Successful release of new and better crop varieties increasingly requires genomics and molecular biology. This volume presents basic information on plant molecular marker techniques from marker location up to gene cloning. The text includes a description of technical approaches in genome analysis such as comparison of marker systems, positional cloning, and array techniques in 19 crop plants.

Overview of molecular technologies. Genebank management. Crop breeding.

The genesis of the volume, Plant Biotechnology and Molecular Markers, has been the occasion of the retirement of Professor Sant Saran Bhojwani from the Department of Botany, University of Delhi. For Professor Bhojwani, retirement only means relinquishing the chair as being a researcher and a teacher which has always been a way of life to him. Professor Bhojwani has been an ardent practitioner of modern plant biology and areas like Plant Biotechnology and Molecular Breeding have been close to his heart. The book contains original as well as review articles contributed by his admirers and associates who are experts in their area of research. While planning this contributory book our endeavour has been to incorporate articles that cover the entire gamut of Plant Biotechnology, and also applications of Molecular Markers. Besides articles on in vitro fertilization and micropropagation, there are articles on forest tree improvement through genetic engineering. Considering the importance of conservation of our precious natural wealth, one article deals with cryopreservation of plant material. Chapter on molecular marker considers DNA indexing as markers of clonal fidelity of in vitro regenerated plants and prevention against bio-piracy. A couple of write-ups also cover stage-specific gene markers, DNA polymorphism and genetic engineering, including raising of stress tolerant plants to sustain productivity and help in reclamation of degraded land.