This book describes the development of genetic resources in amaranths, with a major focus on genomics, reverse, and forward genetics tools and strategies that have been developed for crop improvement. Amaranth is an ancient crop native to the New World. Interest in amaranths is being renewed, due to their adaptability, stress tolerance, and nutritional value. There are about 65 species in the genus, including Amaranthus caudatus L., A. cruentus L., and A. hypochondriacus L., which are primarily grown as protein-rich grains or pseudocereals. The genus also includes major noxious weeds (e.g., A. palmeri). The amaranths are within the Caryophyllales order and thus many species (e.g., A. tricolor) produce red (betacyanin) or yellow (betaxanthin) betalain pigments, which are chemically distinct from the anthocyanins responsible for red pigmentation in other plants. A. hypochondriacus, which shows disomic inheritance (2n = 32; n= 466 Mb), has been sequenced and annotated with 23,059 protein-coding genes. Additional members of the genus are now also been sequenced including weedy amaranths, other grain amaranths, and their putative progenitors.
This book serves the larger community of plant researchers working on the taxonomy, species delimitation, phylogeny, and biogeography of pseudo-cereals, with a special emphasis on amaranths. It also provides extensive information on the nutritive value of underutilized pseudo-cereals, the goal being to broaden the vegetable list. Amaranthus is a cosmopolitan genus of annual or short-lived perennial plants. Most of the species are summer annual weeds and are commonly referred to as pigweed. Only a few are cultivated as vitamin-rich vegetables and ornamentals. The protein-rich seeds of a handful of species, known as grain amaranths, are consumed as pseudo-cereals. Amaranthusmanifests considerable morphological diversity among and even within certain species, and there is no general agreement on the taxonomy or number of species. Currently the genus Amaranthus is believed to include three recognized subgenera and 70 species. Amatanthus is considered to potentially offer an alternative crop in temperate and tropical climate. The classification of amaranths is ambiguous due to the lack of discrete and quantitative species-defining characteristics and the wide range of phenotypic plasticity, as well as introgression and hybridization involving weedy and crop species. It is a known fact that both vegetable and grain amaranths have evolved from their respective weed progenitors. There are more than 180 different weed species that are herbicide-resistant, and amaranths are considered to be leading members of the resistant biotypes. Amaranth species provide ample scope for investigating herbicide resistance mechanisms. Amaranths also show variability in terms of their mating behavior and germplasm, adaptability to different growing conditions, and wide range of variability in sexual systems, from monoecy to dioecy. A solid grasp of these parameters is essential to the future utilization of amaranths as super crops. There are quite a few amaranth research center and germplasm collections all over the world that maintain and evaluate working germplasms. To date, the genetic improvement of amaranths has primarily involved the application of conventional selection methods. But advances in genomics and biotechnology have dramatically enriched the potential to manipulate the amaranth genome, especially improving the amount and availability of nutrients. In conclusion, the book covers all aspects of amaranths, including their food value, significance as vegetables and pseudo-cereals, taxonomy, phylogeny, germplasm variability, breeding behavior and strategies, cultivation practices, and variability in terms of their sexual systems. It offers a valuable resource for all students, researchers and experts working in the field of plant taxonomy and diversity.
The Helix was meant to be a revolution, but even the most pure of intentions can spawn terrible evil, and the revolution of information and innovation they hoped for may not be the one they get.
The impact of global climate change on crop production has emerged as a major research priority during the past decade. Understanding abiotic stress factors such as temperature and drought tolerance and biotic stress tolerance traits such as insect pest and pathogen resistance in combination with high yield in plants is of paramount importance to counter climate change related adverse effects on the productivity of crops. In this multi-authored book, we present synthesis of information for developing strategies to combat plant stress. Our effort here is to present a judicious mixture of basic as well as applied research outlooks so as to interest workers in all areas of plant science. We trust that the information covered in this book would bridge the much-researched area of stress in plants with the much-needed information for evolving climate-ready crop cultivars to ensure food security in the future.
This report is the second in a series of three evaluating underexploited African plant resources that could help broaden and secure Africa's food supply. The volume describes the characteristics of 18 little-known indigenous African vegetables (including tubers and legumes) that have potential as food- and cash-crops but are typically overlooked by scientists and policymakers and in the world at large. The book assesses the potential of each vegetable to help overcome malnutrition, boost food security, foster rural development, and create sustainable landcare in Africa. Each species is described in a separate chapter, based on information gathered from and verified by a pool of experts throughout the world. Volume I describes African grains and Volume III African fruits.
Research on gene drive systems is rapidly advancing. Many proposed applications of gene drive research aim to solve environmental and public health challenges, including the reduction of poverty and the burden of vector-borne diseases, such as malaria and dengue, which disproportionately impact low and middle income countries. However, due to their intrinsic qualities of rapid spread and irreversibility, gene drive systems raise many questions with respect to their safety relative to public and environmental health. Because gene drive systems are designed to alter the environments we share in ways that will be hard to anticipate and impossible to completely roll back, questions about the ethics surrounding use of this research are complex and will require very careful exploration. Gene Drives on the Horizon outlines the state of knowledge relative to the science, ethics, public engagement, and risk assessment as they pertain to research directions of gene drive systems and governance of the research process. This report offers principles for responsible practices of gene drive research and related applications for use by investigators, their institutions, the research funders, and regulators.
The crop plants cater not only to our basic F5 (food, feed, fiber, fuel, and furniture) needs but also provide a number of nutraceuticals with potential nutritional, safety and therapeutic properties. Many crop plants provide an array of minerals, vitamins, and antioxidant-rich bioactive phytochemicals. Increasing incidences of chronic diseases such as cancer, diabetes and HIV, and malnutrition necessitate global attention to health and nutrition security with equal emphasis to food security. This compendium compiles results of researches on biochemical, physiological and genetic mechanisms underlying biosynthesis of the health and nutrition related nutraceuticals. It also explores the precise breeding strategies for augmentation of their content and amelioration of their quality in crop plants under all commodity categories including cereals and millets, oilseeds, pulses, fruits and nuts, and vegetables. The compendium comprise 5 sections dedicated to these 5 commodity groups and presents enumeration on the concepts, strategies, tools and techniques of nutraceutomics. These sections include 50 chapters devoted to even number of major crop plants. These chapters present deliberations on the biochemistry and medicinal properties of the nutracuticals contained; genetic variation in their contents; classical genetics and breeding for their quantitative and qualitative improvement; tissue culture and genetic engineering for augmentation of productivity and quality; and sources of genes underlying their biosynthesis. They also include comprehensive enumeration on genetic mapping of the genes and QTLs controlling the contents and profile of the nutraceuticals and molecular breeding for their further improvement through marker assisted selection and backcross breeding tools. Prospects of post-genomic precise breeding strategies including genome-wide association mapping, genomic selection, allele mining, and genome editing are also discussed. This compendium fills the gap in academia, and research and development wings of the private sector industries interested in an array of subjects including genetics, genomics, tissue culture, genetic engineering, molecular breeding, genomics-assisted breeding, bioinformatics, biochemistry, physiology, pathology, entomology, pharmacognosy, IPR, etc., and will also facilitate understanding of the policy making agencies and people in the socio-economic domain and research sponsoring agencies.
Biotic stresses cause yield loss of 31-42% in crops in addition to 6-20% during post-harvest stage. Understanding interaction of crop plants to the biotic stresses caused by insects, bacteria, fungi, viruses, and oomycetes, etc. is important to develop resistant crop varieties. Knowledge on the advanced genetic and genomic crop improvement strategies including molecular breeding, transgenics, genomics-assisted breeding and the recently emerging genome editing for developing resistant varieties in vegetable crops is imperative for addressing FPNEE (food, health, nutrition. energy and environment) security. Whole genome sequencing of these crops followed by genotyping-by-sequencing have facilitated precise information about the genes conferring resistance useful for gene discovery, allele mining and shuttle breeding which in turn opened up the scope for 'designing' crop genomes with resistance to biotic stresses. The nine chapters each dedicated to a vegetable crop or crop-group in this volume will deliberate on different types of biotic stress agents and their effects on and interaction with crop plants; will enumerate on the available genetic diversity with regard to biotic stress resistance among available cultivars; illuminate on the potential gene pools for utilization in interspecific gene transfer; will brief on the classical genetics of stress resistance and traditional breeding for transferring them to their cultivated counterparts; will enunciate the success stories of genetic engineering for developing biotic stress resistant varieties; will discuss on molecular mapping of genes and QTLs underlying biotic stress resistance and their marker-assisted introgression into elite varieties; will enunciate on different emerging genomics-aided techniques including genomic selection, allele mining, gene discovery and gene pyramiding for developing resistant crop varieties with higher quantity and better quality; and will also elaborate some case studies on genome editing focusing on specific genes for generating disease and insect resistant crops.
Pseudocereals, belonging to the genus Amaranthus, have been cultivated for their grains for 8,000 years or more. The grain was a staple food of the Aztecs and was also considered an integral part of Aztec religious ceremonies. The book primarily focuses on the nutrient properties of amaranth and expresses its viewpoint in considering this crop as a remedy for many nutrient deficiencies and curbing food insecurity. The functional properties of the grain are immense and it is clear that the crop would be a valuable agricultural product around the world.
