The rudimentary embryo: an early angiosperm invention that contributed to their dominance over gymnosperms

Abstract In this review, we explore the origin of rudimentary embryo, its relationship to other kinds plant embryos and role in diversification angiosperms. Rudimentary have a length:width ratio ≤2.0, they organs, including cotyledon(s) primary root. A literature survey failed reveal pre-angiosperms, suggesting that kind embryo is an angiosperm invention. Although proembryos some gymnosperms angiosperms not formed meristems or organs. Thus, are proembryos. During development monocots dicots (all non-monocots), growth pattern epicotyledonary cells differs, resulting differences placement shoot meristem one versus two cotyledons, respectively, but size similar. grow inside seed prior germination, which true for linear-underdeveloped embryos, those gymnosperms. served as starting point great ultimately seeds, angiosperms, still present many families extant The part syndrome changes, increased speed pollen germination tube growth, simplification female gametophyte, endosperm elimination multiple production from each zygote, distinguish We conclude was new developments contributed their success on earth.