Induction of Fruit Set in Vitis vinifera L. by a Kinin

Abstract

THE work of Gustafson¹ in 1936 and subsequent experiments by others led to the general conclusion that auxin is the controlling factor in fruit set. Results collected over the past 6 or 7 years show that gibberellins are also concerned with fruit set and development^2,3. It is now accepted that a third major group of plant hormones, the kinins, occur in many fruits^4–6, In 1962 we were the first to demonstrate that an applied kinin caused a large increase in size of fruit. Treated berries of ‘Black Corinth’ grapes became three times as large as the untreated⁷. This communication describes experiments performed in 1963 and 1964 to determine the effect of kinin on fruit set.