The Role of Hormones in Fruit Set and Development

Abstract

This subject has been reviewed periodically by Nitsch (60) in 1953, Luckwill (53) in 1959, Leopold (47) in 1962, and lastly by Crane (19) in 1964. It has been pointed out repeatedly that the seeds in fruits are rich sources particularly of auxins, but also of gibberellins and cytokinins as well. Various types of evidence would indicate that these hormones emanating from the seeds stimulate growth of the fruit tissues surrounding them and also control fruit abscission. For example, in many fruits marked correlations exist between seed number and ultimate fruit size and also between seed distribution and fruit shape. Fruits that absciss prematurely are usually multi-seeded ones with a lower seed content than normal, or are single or multi-seeded fruits in which the seeds abort.