Variation Within Pure Lines of Wild Oats (Avena fatua) in Relation to Degree of Primary Dormancy

Abstract

The germination of caryopses on water or GA3solutions was used to characterize the degree of primary dormancy present in the seed progeny of 10 genetically pure lines of wild oats (Avena fatuaL. # AVEFA). These 10 lines represented a range of types from lines exhibiting no dormancy to those with a high degree of dormancy. Repeated propagation of these pure lines under constant environmental conditions identified several genetically inherited characters that were associated with the inherited differences in degree of primary dormancy. Correlation of the seed development period, number of primary caryopses produced, and caryopsis moisture content to the degree of primary dormancy shows: a) Lines characterized by low degrees of primary dormancy were, in general, those that had a short seed development time and produced few heavy seed low in percent water; and b) lines characterized by high degrees of primary dormancy were, in general, those that had a long seed development time and produced many light seed high in percent water. The adaptive advantage of the coupling of physiological and morphological characters with degree of dormancy is discussed and the possibility that some characters are determined by others is indicated.