Influence of Cane Number and Diameter, Irrigation, and Carbohydrate Reserves on the Fruit Number of Red Raspberries1

Abstract

Fruitfulness of individual red raspberry ( Rubus idaeus L.) canes was increased by reduction of cane number per hill and by increase in cane diameter. Yield per hectare, however, was greatly increased by more canes per hill. Floral primordia bud number was more advanced in the fall on small-diameter canes, but the difference between small- and large-diameter canes disappeared by spring. Berry number and percentage fruit set were greater for large-diameter canes and were related to amount of available carbohydrate per node. Excessive moisture stress in late summer tended to delay carbohydrate build up.