ABSTRACT
This chapter reports on results which, using new genetic stocks and material grown in 1985, describe the location of germination alpha-amylases within the ear and their appearance within grains during maturation. The eventual elucidation of the underlying physiological mechanism may indicate directed genetic breeding strategies to reduce weather damage losses from the source. The chapter implicates gibberellins in the expression of the syndrome and leads to speculate that the gibberellins involved are not the l-beta-hydroxylated compounds normally found in developing wheat grains but gametophytic factor (Ga) released from the maturing embryo. As there is no evidence that GA is produced during late grain development and it was not detected in grains of tall lines harvested 43 days post anthesis in material used to obtain the information. The abscisic acid results are included to demonstrate that the GA-insensitivity is not caused via effects on the inhibitor.
