Haploids in Crop Improvement II


Book Description

Doubled haploid technology is an important tool for plant breeding. It allows for significant time reduction in the achievement of homozygous breeding lines of value in crop improvement. This volume provides an excellent overview of haploid induction and the application of doubled haploids. The authors emphasize advances made in the understanding of microspore embryogenesis, but treat also advances in gynogenesis and the manipulation of parthenogenetic haploid development. The text contains a thorough discussion of the application of haploidy to the improvement of a number of species from various families, including Brassicaceae, Poaceae, and Solanaceae. The various methods applicable to these species are described in detail. Each chapter contains critical evaluation of the scientific literature and an extensive list of references. This volume is ideally suited for plant breeders, geneticists, and plant cell biologists.




Haploids in Crop Improvement I


Book Description

Haploid plants have the gametophytic number of chromosomes. They are of great importance, especially in studies on the induction of muta tions and also for the production of homozygous plants, they are needed in large numbers. The conventional methods employed by plant breeders for their production are cumbersome, time-consuming, laborious and rather inefficient. Sometimes it may take years to produce a pure line. However, with the introduction of in vitro techniques, especially anther culture for the induction of androgenesis, it has become increasingly evi dent that these methods considerably accelerate the production of haploids for plant breeding programs. During the last decade, in vitro-produced haploids have been incor porated into breeding programs of many agricultural crops, and positive results have been obtained especially with rice, wheat, potato, barley, maize, asparagus, sunflower, brassica, tobacco, etc. Among these, rice and wheat are the best examples in which a number of improved varieties have been released. In wheat, the breeding cycle can be shortened by three or four generations when the pollen haploid breeding method is used instead of conventional cross-breeding. The release of the wheat varieties Jinghua 1 and Florin is a typical example of what can be achieved with other crops. Taking these developments into considera tion, the present volume, Haploids in Crop Improvement I, was compil ed.




Doubled Haploid Production in Crop Plants


Book Description

The production of doubled haploids has become a necessary tool in advanced plant breeding institutes and commercial companies for breeding many crop species. However, the development of new, more efficient and cheaper large scale production protocols has meant that doubled haploids are also recently being applied in less advanced breeding programmes. This Manual was prepared to stimulate the wider use of this technology for speeding and opening up new breeding possibilities for many crops including some woody tree species. Since the construction of genetic maps using molecular markers requires the development of segregating doubled haploid populations in numerous crop species, we hope that this Manual will also help molecular biologists in establishing such mapping populations. For many years, both the Food and Agriculture Organization of the United Nations (FAO) and the International Atomic Energy Agency (IAEA) have supported and coordinated research that focuses on development of more efficient doubled haploid production methods and their applications in breeding of new varieties and basic research through their Plant Breeding and Genetics Section of the Joint F AO/IAEA Division of Nuclear Techniques in Food and Agriculture. The first F AO/IAEA scientific network (Coordinated Research Programme - CRP) dealing with doubled haploids was initiated by the Plant Breeding and Genetics Section in 1986.




Advances in Haploid Production in Higher Plants


Book Description

The importance of haploids is well known to geneticists and plant breeders. The discovery of anther-derived haploid Datura plants in 1964 initiated great excitement in the plant breeding and genetics communities as it offered shortcuts in producing highly desirable homozygous plants. Unfortunately, the expected revolution was slow to materialise due to problems in extending methods to other species, including genotypic dependence, recalcitrance, slow development of tissue culture technologies and a lack of knowledge of the underlying processes. Recent years have witnessed great strides in the research and application of haploids in higher plants. After a lull in activities, drivers for the resurgence have been: (1) development of effective tissue culture protocols, (2) identification of genes c- trolling embryogenesis, and (3) large scale and wide spread commercial up-take in plant breeding and plant biotechnology arenas. The first major international symposium on “Haploids in Higher Plants” took place in Guelph, Canada in 1974. At that time there was much excitement about the potential benefits, but in his opening address Sir Ralph Riley offered the following words of caution: “I believe that it is quite likely that haploid research will contr- ute cultivars to agriculture in several crops in the future. However, the more extreme claims of the enthusiasts for haploid breeding must be treated with proper caution. Plant breeding is subject from time to time to sweeping claims from ent- siastic proponents of new procedures.




Rice Improvement


Book Description

This book is open access under a CC BY 4.0 license. By 2050, human population is expected to reach 9.7 billion. The demand for increased food production needs to be met from ever reducing resources of land, water and other environmental constraints. Rice remains the staple food source for a majority of the global populations, but especially in Asia where ninety percent of rice is grown and consumed. Climate change continues to impose abiotic and biotic stresses that curtail rice quality and yields. Researchers have been challenged to provide innovative solutions to maintain, or even increase, rice production. Amongst them, the ‘green super rice’ breeding strategy has been successful for leading the development and release of multiple abiotic and biotic stress tolerant rice varieties. Recent advances in plant molecular biology and biotechnologies have led to the identification of stress responsive genes and signaling pathways, which open up new paradigms to augment rice productivity. Accordingly, transcription factors, protein kinases and enzymes for generating protective metabolites and proteins all contribute to an intricate network of events that guard and maintain cellular integrity. In addition, various quantitative trait loci associated with elevated stress tolerance have been cloned, resulting in the detection of novel genes for biotic and abiotic stress resistance. Mechanistic understanding of the genetic basis of traits, such as N and P use, is allowing rice researchers to engineer nutrient-efficient rice varieties, which would result in higher yields with lower inputs. Likewise, the research in micronutrients biosynthesis opens doors to genetic engineering of metabolic pathways to enhance micronutrients production. With third generation sequencing techniques on the horizon, exciting progress can be expected to vastly improve molecular markers for gene-trait associations forecast with increasing accuracy. This book emphasizes on the areas of rice science that attempt to overcome the foremost limitations in rice production. Our intention is to highlight research advances in the fields of physiology, molecular breeding and genetics, with a special focus on increasing productivity, improving biotic and abiotic stress tolerance and nutritional quality of rice.




In Vitro Haploid Production in Higher Plants


Book Description

The 18 chapters making up In Vitro Haploid Production in Higher Plants are divided into two sections. Section 1 (eight chapters) covers historical and fundamental aspects of haploidy in crop improvement. Section 2 deals with methods of haploid production, including anther culture, micropore culture, ovary culture, pollination with irradiated pollen, in vitro pollination, and special culture techniques, including polyhaploid production in the Triticeae by sexual hybridization, the influence of ethylene and gelling agents on anther culture, conditional lethal markers, and methods of chromosome doubling.




In Vitro Haploid Production in Higher Plants


Book Description

Since the beginning of agricultural production, there has been a continuous effort to grow more and better quality food to feed ever increasing popula tions. Both improved cultural practices and improved crop plants have al lowed us to divert more human resources to non-agricultural activities while still increasing agricultural production. Malthusian population predictions continue to alarm agricultural researchers, especially plant breeders, to seek new technologies that will continue to allow us to produce more and better food by fewer people on less land. Both improvement of existing cultivars and development of new high-yielding cultivars are common goals for breeders of all crops. In vitro haploid production is among the new technologies that show great promise toward the goal of increasing crop yields by making similar germplasm available for many crops that was used to implement one of the greatest plant breeding success stories of this century, i. e. , the development of hybrid maize by crosses of inbred lines. One of the main applications of anther culture has been to produce diploid homozygous pure lines in a single generation, thus saving many generations of backcrossing to reach homozygosity by traditional means or in crops where self-pollination is not possible. Because doubled haploids are equivalent to inbred lines, their value has been appreciated by plant breeders for decades. The search for natural haploids and methods to induce them has been ongoing since the beginning of the 20th century.




Androgenesis and Haploid Plants


Book Description

Jointly published with INRA, Paris. The use of haploid plants is of increasing importance in plant biology and plant breeding. This book illustrates how the advances in plant molecular and cell biology provide an exciting means for the analysis of androgenesis in terms of pollen development and the initiation of embryogenesis. It provides both an appraisal of techniques and their practical application, and is the most up-to-date source of information about the biology of gametophytes.




Somatic Hybridization in Crop Improvement II


Book Description

Somatic hybrids through the fusion of plant protoplasts have widened the genetic variability of cultivated plants. As "Somatic Hybridization in Crop Improvement I", published in 1994, this volume describes how this discipline can contribute to the improvement of crops. It comprises 24 chapters dealing with interspecific and intergeneric somatic hybridization and cybridization. It is divided into four sections: I. Cereals: Barley, rice, and wheat. II. Vegetables and Fruits: Arabidopsis, Asparagus, Brassica, chicory, Citrus, Cucumis, Diospyros, Ipomoea, and various Solanaceous species, e.g., tomato, potato, and eggplant. III. Medicinal and Aromatic Plants: Atropa, Dianthus, Nicotiana, and Senecio. IV. Legumes/Pasture Crops: Alfalfa. This book is tailored to the needs of advanced students, teachers and researchers in the fields of plant breeding, genetic engineering, and plant tissue culture.




Somaclonal Variation in Crop Improvement II


Book Description

In continuation of Somaclonal Variation and Crop Improvement I (1990), this volume is comprised of twenty-four chapters dealing with somaclonal variants showing resistance to salt/drought, herbicides, viruses, Alternaria, Fusarium, Glomerella, Verticillium, Phytophthora, fall armyworm, etc. in a number of plants of economic importance. It is divided into two sections: Section I. Somaclonal Variation in Agricultural Crops: wheat, rice, maize, sorghum, potato, tomato, Lotus, Stylosanthes, banana, strawberry, citrus, colt cherry. Section II. Somaclonal Variation in Medicinal and Aromatic Plants: Atropa, Carthamus, Hypericum, Lavatera, Nicotiana, Primula, Rauwolfia, Scilla, and Zinnia. This book will be of great assistance to research workers, teachers, and advanced students of plant pathology, tissue culture, pharmacy, horticulture, and especially plant breeding.