The Conifers Genomes Variation And Evolution

This book is the first comprehensive volume on conifers detailing their genomes, variations, and evolution. The book begins with general information about conifers such as taxonomy, geography, reproduction, life history, and social and economic importance. Then topics discussed include the full genome sequence, complex traits, phenotypic and genetic variations, landscape genomics, and forest health and conservation. This book also synthesizes the research included to provide a bigger picture and suggest an evolutionary trajectory. As a large plant family, conifers are an important part of economic botany. The group includes the pines, spruces, firs, larches, yews, junipers, cedars, cypresses, and sequoias. Of the phylum Coniferophyta, conifers typically bear cones and evergreen leaves. Recently, there has been much data available in conifer genomics with the publication of several crop and non-crop genome sequences. In addition to their economic importance, conifers are an important habitat for humans and animals, especially in developing parts of the world. The application of genomics for improving the productivity of conifer crops holds great promise to help provide resources for the most needy in the world.

With contributions by internationally reputed researchers in the field, this book presents the implications of the genomic revolution for conifers-promoting a better understanding of the evolution of these organisms as well as new knowledge about the molecular basis of quantitative trait variation. Both of these discoveries play important roles in

Technical advances have accelerated the structural and functional exploration of conifer genomes and opened up new approaches to study their physiology and adaptation to environmental conditions. This thesis focuses on the evolution of conifer genes and explores (i) the genomic factors that have impacted the evolution of gene structure and (ii) the evolution of a large gene family involved in drought tolerance, the dehydrins. The analysis of gene structure was based on white spruce (Picea glauca [Moench] Voss) sequence data from BAC clones, the genome assembly and the gene space obtained from sequence capture. Through comparative analyses, we found that conifers presented more intronic sequence per gene than most flowering plants (angiosperms) and that the average intron length was not directly correlated to genome size. We found that repetitive elements, which are responsible for the very large size of conifer genomes, also affect the evolution of exons and introns. In the second part of the thesis, we undertook the first exhaustive analysis of the dehydrin gene family in conifers. The phylogenetic analyses indicated the occurrence of a series of gene duplications in conifers and a major lineage duplication, which caused the expansion of the dehydrin family in the genus Picea. Conifer dehydrins have an array of modular amino acid structures, and in spruce, these structures are particularly diverse and are associated with different expression patterns in response to dehydration stress. Taken together, our findings suggest that the evolution of gene structure is dynamic in conifers, which contrast with a widely accepted slow rate of chromosome evolution. They further indicate that the expansion and diversification of adaptation-related genes, like the dehydrins in spruce, may confer the phenotypic plasticity to respond to the environmental changes during their long life span.

Global climate change requires the development of programs that consider the active restoration of degraded forests and the use of native trees in afforestation to preserve the natural environment. International commitments like the UN REDD program, the Montréal Process and the Convention on Biological Diversity call for the breeding of species rarely contemplated by large industrial companies. Low-intensity breeding is the most rational strategy for those species: simple but robust, and not dependent on continuously increasing funding, and therefore effective even with a relatively small budget. It commonly focuses on high genetic diversity rather than improving economic traits and adaptability rather than productivity. Controlled crosses with full pedigrees typical of high-intensity breeding are replaced by open pollination. This book presents state-of-the-art breeding strategies from the last two decades for several forest tree species of prime importance in the natural forests of Argentina. They are distributed in the three main forestry ecoregions of the country: the subtropical dry forest (Chaco), the subtropical rain forests (Yungas and Alto Paraná rainforests) and the temperate forests of Patagonia. The book also discusses the genetic patterns of the selected species defined using genetic markers together with the analysis of the variation in quantitative traits. Further, it examines the crucial features of their reproductive biology, such as the mating system and gene flow and describes the current breeding programs. Lastly, it presents the latest developments in genetic resources and their emerging applications, concluding with some reflections and perspectives related to the conditioning imposed by climate change.

In our modern world, it is easy to overlook the natural world all around us. Only major life events, such as birth, injury, disease, and death, remind us that we are still biological organisms. We "interact" with nature in controlled and safe environments, such as zoos, theme parks, or through different forms of media. Television shows, films, and books are nearly always in exotic locations (e.g., the Kalahari Desert, the deep ocean, or Antarctica), but they inadvertently reinforce our separation from nature. Biology happens somewhere else. Author Gary Howard seeks to change that perception. The Biology of Us describes the common but fascinating examples of biology and nature that are hidden in plain sight in our daily lives. It focuses on human biology, but describes animals and plants all around, on, and in us to put human features into an evolutionary context. Many aspects of ourselves and our normal activities are examples of evolution: breathing, eating, standing up, communicating, telling time, and more. This book illustrates evolutionary strategies used successfully by common organisms for hundreds of millions of years. Howard shows that the organisms in our daily lives are not trivial neighbors or even pests but are just as amazing as those in the Serengeti or the Galápagos Islands.

Forest tree improvement has mainly been implemented to enhance the productivity of artificial forests. However, given the drastically changing global environment, improvement of various traits related to environmental adaptability is more essential than ever. This book focuses on genetic information, including trait heritability and the physiological mechanisms thereof, which facilitate tree improvement. Nineteen papers are included, reporting genetic approaches to improving various species, including conifers, broad-leaf trees, and bamboo. All of the papers in this book provide cutting-edge genetic information on tree genetics and suggest research directions for future tree improvement.

This book offers comprehensive information on the genomics of spruces (Picea spp.), naturally abundant conifer tree species that are widely distributed in the Northern Hemisphere. Due to their tremendous ecological and economic importance, the management of forest genetic resources has chiefly focused on conservation and tree improvement. A draft genome sequence of the 20-gigabase Norway spruce genome was published in the journal Nature in 2013. Continuous efforts to improve the spruce genome assembly are underway, but are hindered by the inherent characteristics of conifer genomes: high amounts of repetitive sequences (introns and transposable elements) in the genome and large gene family expansions with regards to abiotic stress, secondary metabolism and spruces' defense responses to pathogens and herbivory. This book presents the latest information on the status of genome assemblies, provides detailed insights into transposable elements and methylation patterns, and highlights the extensive genomic resources available for inferring population genomics and climate adaptation, as well as emerging genomics tools for tree improvement programs. In addition, this volume features whole-genome comparisons among conifer species, and demonstrates how functional genomics can be used to improve gene function annotations. The book closes with an outlook on emerging fields of research in spruce genomics.

The book is written for policy experts, life scientists, government and business leaders, biotechnology writers and social activists. Few decision-makers realize the unprecedented degree to which transgenic technology is now possible for forests on a commercial scale. Only a handful of the 550 living conifer species is used for commodity value and even fewer species are being developed for transgenic plantations. Transgenic field trials started within the last decade but no transgenic pine plantations exist in 2005. But emergence of transgenic forest trees is still so recent that dialogue about the pros and cons is confined to the scientific community. And dialogue must move out into the public domain. The goal of this volume is to provide content for public deliberations about the genetic composition of future forests. Its Section I is composed of provocative and opposing views on the question of transgenic conifer plantations. Sections II and III follow with research advances on relevant conifer genomics and ecology research, respectively. Section IV forecasts rates of technology adoption for different case studies. Finally, Section V compares the status of regulatory oversight of transgenic forest trees between Canada and the United States.