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Embryonic development represents an important reproductive phase of sexually reproducing plant species. The fusion of egg and sperm produces the plant zygote, a totipotent cell that, through cell division and cell identity specification in early embryogenesis, establishes the major cell lineages and tissues of the adult plant. The subsequent morphogenesis phase produces the full-sized embryo, while the late embryogenesis maturation process prepares the seed for dormancy and subsequent germination, ensuring continuation of the plant life cycle. In this review on embryogenesis, we compare the model eudicot Arabidopsis thaliana with monocot crops, focusing on genome activation, paternal and maternal regulation of early zygote development, and key organizers of patterning, such as auxin and WOX transcription factors. While the early stages of embryo development are apparently conserved among plant species, embryo maturation programs have diversified between eudicots and monocots. This diversification in crop species reflects the likely effects of domestication on seed quality traits that are determined during embryo maturation, and also assures seed germination in different environmental conditions. This review describes the most important features of embryonic development in plants, and the scope and applications of genomics in plant embryo studies., During plant embryogenesis, developmentally specified patterning and morphogenesis define embryonic programs. In recent years, significant advances have been made using Arabidopsis that revealed important insights into these key biological programs. This review presents recent progress in transcriptomic and genomic studies of embryo development in Arabidopsis, dicot, and monocot crop species and discusses findings implications to prospects in crop seeds. more...

Embryogenesis in flowering plants has fascinated biologists since at least the 19th century. Embryos of almost all flowering plants share common characteristics, including an asymmetric first division of the zygote, and multiple rounds of cell divisions that generate the major tissue types of the adult plant, usually within a few days of fertilization. This review focuses on early embryogenesis, including fertilization, the contributions of maternal and paternal genomes to the zygote and early embryo, cell fate decisions that create the apical and basal lineages, establishment of the shoot and root meristems, and formation of the other major tissue types in the adult plant. Because most genetic and molecular research on embryogenesis in plants has been conducted on the model species Arabidopsis thaliana, we highlight work on this species as well as research with Zea mays (maize) and Oryza sativa (rice). more...