Chemical Changes in Developing Seeds of `Independence' Nectarine and `Fay Elberta' Peach

To learn why embryos of early ripening stone fruits abort or fail to germinate, the growth and nutrition of developing seeds of `Independence' nectarine and `Fay Elberta' peach (Prunus persica, Batsch.) were compared. Seeds were collected at weekly intervals, beginning 2 months after full bloom until the fruits were ripe. Fruit diameter, seed and embryo lengths, and fresh weights of nucellus and endosperm were recorded. Parts of the seeds were analyzed for soluble carbohydrates, fats, and total N. At the same phonological stages of fruit development, concentrations of these seed fractions were nearly equal for both cultivars. Percentage composition of all fractions varied with time, but increased on a per-seed basis. Sucrose was the major soluble carbohydrate in embryos of both cultivars. Nitrogen content of the embryos, on a percent dry matter basis, gradually decreased from the 12th week after full bloom to harvest.