Primary Dormancy in Tomato. Further Studies with the sitiens Mutant

Abstract

Over the past ten years the non-dormant ABA-deficient sitiens mutant of tomato (Lycopersicon esculentum cv. Moneymaker) has been used to study primary dormancy. Much of the attention has been focussed on the role of endosperm softening, a prerequisite for radicle protrusion, and control of this process by plant hormones. Other studies were directed at water relations of the embryo with regard to embryo expansion and radicle elongation. Only recently studies of a possible role of the seed coat were initiated. A short summary will be given of these results and what they have taught us about the mechanism and control of tomato seed dormancy.