Apomixis is the consequence of a concerted mechanism that harnesses the sexual machinery and coordinates developmental steps in the ovule to produce an asexual (clonal) seed. Altered sexual developments involve widely characterized functional and anatomical changes in meiosis, gametogenesis, and embryo and endosperm formation. The ovules of apomictic plants skip meiosis and form unreduced female gametophytes whose egg cells develop into a parthenogenetic embryo, and the central cells may or may not fuse to a sperm to develop the seed endosperm. Thus, functional apomixis involves at least three components, apomeiosis, parthenogenesis, and endosperm development, modified from sexual reproduction that must be coordinated at the molecular level to progress through the developmental steps and form a clonal seed. Despite recent progress uncovering specific genes related to apomixis-like phenotypes and the formation of clonal seeds, the molecular basis and regulatory network of apomixis is still unknown. This is a central problem underlying the current limitations of apomixis breeding. This book collates twelve publications addressing different topics around the molecular basis of apomixis, illustrating recent discoveries and advances toward understanding the genetic regulation of the trait, discussing the possible origins of apomixis and the remaining challenges for its commercial deployment in plants.

Apomixis is a difficult-to-analyse trait with a complex molecular basis and a substantive effect on the biology of a species. Thus, apomixis is an interesting characteristic for researchers and students working in different fields of plant science and agriculture, and technological advances are enabling and making apomixis studies more common. Apomixis in Angiosperms: Mechanisms, Occurrences, and Biotechnology provides a systematic introduction to the mechanisms and developmental types of apomixis along with an overview of alternative methodologies for identifying apomixis and a detailed reassessment of the occurrences of apomictic species among angiosperm families. Optional methods are illustrated with examples of all types of apomixis and biological levels of analysis, i.e. cells, ovules, seeds and offspring. Data on apomictic species are collected in tables along with information on ploidy, type of apomixis and references. Occurrences of apomixis are briefly discussed in phylogenetic and evolutionary contexts. An outline of the molecular basis of apomixis in plants is presented, together with prospects and challenges that remain for its biotechnological exploitation. This book: Provides a systematic overview of the mechanisms of apomixis, developmental types and methodology for apomixis research. Reassesses apomixis at the species level in angiosperm families. Contains tables summarizing relevant information on apomixis. Analyses occurrences of apomixis in phylogenetic and evolutionary contexts. Outlines the molecular basis and biotechnological perspective of apomixis breeding. This book presents an accessible overview of apomixis research and a curated dataset of apomictic species. It serves as a reference book for students, researchers and citizen scientists interested in apomixis, as well as researchers, business innovators and entrepreneurs pursuing apomixis breeding. It can also be used as a textbook in graduate courses on plant reproduction.

Apomixis in Plants presents a comprehensive review of different aspects of asexual seed formation in plants. This is important in plant research since apomixis could greatly facilitate breeding in important crops. It is also interesting theoretically because it carries problems related to genetic variation and evolution to its extreme. The book features a broad selection of topics, including a historical review of ideas and landmarks in the field; comparisons with other types of asexual reproduction in higher plants and with related phenomena in animals and related plants; a presentation of cytology and embryology of apomicts and the diversified terminology in the field; views on the genetic background of apomixis and environmental effects on its expression; and the interrelation between apomixis and other traits. Additional topics covered include classical and modern theories of sexual versus asexual reproduction; geographical and taxonomical trends in apomicts; ecological implications of apomixis, and a review of future possibilities for using apomixis in plant breeding. Apomixis in Plants is an important reference volume for researchers and students in all areas of botany, ecology, and plant breeding.

Apomixis in Angiosperms: Nucellar and Integumentary Embryony is based on original cytoembryological data and critically reviewed literature on more than 250 species from 57 families of angiosperms. The book covers the complete process of nucellar and integumentary embryo formation and viable seed development within species, families, and among angiosperms in general. Many species (some of which are economically important) characterized by adventive embryony are listed. The book also provides an original simple classification of apomixis and offers a new approach to differentiating embryological structures in cases of apomixis and amphimixis. Apomixis in Angiosperms: Nucellar and Integumentary Embryony will be a useful reference for embryologists, botanists, cytologists, geneticists, and plant breeders. It will also benefit any researcher interested in studying somatic embryo formation in tissue culture.

Plant Development and Evolution, the latest release in the Current Topics in Developmental Biology series, highlights new advances in the field, with this new volume presenting interesting chapters on the Evolution of the plant body plan, Lateral root development and its role in evolutionary adaptation, the Development of the vascular system, the Development of the shoot apical meristem and phyllotaxis, the Evolution of leaf diversity, the Evolution of regulatory networks in land plants, The role of programed cell death in plant development, the Development and evolution of inflorescence architecture, the Molecular regulation of flower development, the Pre-meiotic another development, and much more. - Provides the authority and expertise of leading contributors from an international board of authors - Presents the latest release in the Current Topics in Developmental Biology series - Updated release includes the latest information on Plant Development and Evolution

Apomixis for rice improvement; Transferring apomixis to maize; Transfer of alien chromosome-carrying gene for apomixis to cultived pennisetum; Cytological mechanisms of apospory and diplospory; Genetics of apomixis mechanisms; Embryo and flower development in rice and apomixis in Chinese chive (Allium tuberosum); Modifying embryo sac development and strategies for cloning the apomixis gene from buffelgrass; Molecular markers for apomixis in Pennisetum; Using Arabidopsis in the analysis of megaspore development; Developmental genetics of floral patterning in Arabidopsis thaliana; Isolating apomictic mutnats in Arabidopsis thaliana - prospects adn progess.

The great diversity of land plants (especially angiosperms) is mainly reflected in the diversity of various reproductive organs of plants. However, despite long time intensive investigations, there are still uncertainties and sometimes misunderstandings over the nature and evolution of reproductive organs in land plants. With the new advances made in various fields of botany (especially at molecular level), there is increasing light shed on some aspects of flowers (reproductive organs of angiosperms). In this ebook, we collect 15 papers reporting new understanding on plant reproductive organs. These works range from morphology and anatomy to molecular regulatory networks underlying traditional observations. We understand this single book cannot reach our goal, but we do hope that this book can contribute to or initiate some efforts leading to the final solution of some problems concerning the homology and evolution of reproductive organs in plants.