Relationships Between Fruit Size and Seed Number and Size in Blackberries

Abstract

Fruit enlargment in higher plants is controlled by complex physiological processes resulting from hormonal activity (2, 11, 12). In these processes, ovule fertilization and subsequent seed development play a leading role. In some "many seeded" fruits, it has been found that seed number is positively correlated with mature fruit size (1, 3, 5, 7, 8, 9). Seed size may also be important in determining fruit size in some species (8) but not in others (9). In the blackberry, large fruit size is important in harvesting and marketability of the fruit and small seeds are preferred in fresh and processed blackberry products. Wide variations in seed size among genetic clones of blackberry (4, 14) and raspberry (13) have been reported. This investigation was conducted to determine the effects of seed number and size on fruit size of the cultivated blackberry.