Spikelet Number, Its Control and Relation to Yield Per Ear in Wheat

For 12 cultivars of wheat grown under a 21°C day/16°C night temperature regime, spikelet number was closely related to grain number, but not to grain yield per ear as individual grain weights differed considerably between cultivars. However, when spikelet number was varied by day length or vernalization treatment, grain yield per ear was clearly dependent on spikelet number within each cultivar.