Estimating out-crossing rates in spring wheat cultivars using the contact method

Wheat (Triticum aestivum L.) is a self-pollinated species with outcrossing (OC) rates assumed to be less than 1%. The objective of this study was to evaluate the OC rates for 35 Canadian spring wheat cultivars grown under greenhouse conditions. Recipient cultivars were crossed with Purendo-38, a blue aleurone wheat, using direct spike contact inside glassine bags. Four seeding dates were used in each of two greenhouse experiments (2001 and 2002). Out-crossing rates ranged from 0 to 2.8% (2001) and 0 to 3.5% (2002), with the exception of 'Glenlea' and 'Wildcat'. Only Glenlea (10.6% [20011; 8.6% [2002]) and Wildcat (6.3% [2001]; 4.2% [2002]) displayed consistently elevated levels of OC.