The transition from seed to seedling and implications for stress resistance
One of the most important developmental processes in the life-cycle of higher plants is the transition from a seed to a plant and from a generative to a vegetative developmental program. The major hallmark or end-point of the transition from seed to plant is the onset of photosynthesis and the concomitant shift from a heterotrophic to an autotrophic organism. In general, it is advantageous for a species to keep the period of seedling establishment as short as possible since young seedlings are highly sensitive to biotic and abiotic stresses. Seedling death is one of the main causes of yield losses in crops growing under sub-optimal conditions. This implies that the extreme stress tolerance of seeds to e.g. heat and drought is lost upon germination. If the regulatory principles involved in seed to seedling transition are better understood it may become feasible to maintain the seed’s stress tolerance well into the seedling stage.