Combinatorial Networks Regulating Seed Development and Seed Filling

Seeds offer plants a unique opportunity to suspend their life cycles in a desiccated state. This enables them to endure adverse environmental conditions and then resume growth by using endogenous storage products when more favorable conditions develop. Seed development is pivotal to the reproductive success of flowering plants (Angiosperms). It is initiated by the process of double fertilization that gives rise to the embryo and the endosperm. The embryo develops following fertilization of the haploid egg cell by one of the sperm cells leading to the formation of a diploid zygote. In contrast, the triploid endosperm results from the fertilization of the maternal homodiploid central cell of the ovule by another sperm cell (Weterings & Russell, 2004). The diploid embryo and the triploid endosperm develop concertedly inside the maternal ovule and are protected by a seed coat constituted of maternally derived inner and outer integuments. The seed coat provides an important interface between the embryo and the external environment (Haughn & Chaudhury, 2005). Thus, different genome combinations contribute to seed ontogeny.