Frequency of Outcrossing and Isolation Distance in Faba Beans (Vicia faba L.)

Faba beans (Vicia faba L.) constitute a partially outcrossing species requiring an isolation distance to maintain genetic purity when more than one variety is grown in field conditions. This information crucial for seed growers and bean breeders. A study was conducted at the University of Sydney’s Plant Breeding Institute, Narrabri, over two years examine extent natural using creamy white flower characteristic as morphological marker, which controlled by single recessive gene. The white-flowered genotype (IX225c) paired rows 150 m length four directions from central 480 m2 plot normal flowered PBA Warda. beehive placed flowering time pollination allowed. At maturity, samples were taken designated intervals along each axis 100 seeds sample glasshouse/birdcage 4–5 leaf stage proportion plants displaying stipule spot pigmentation (normal color spotted are linked) used determine percentage outcrossing. Maximum 2.28% occurred where both genotypes side (0 m) degree decreased increased. 6 distance, less 1%; however, on occasion, it increased 1% beyond m, indicating volatile unpredictable nature bee flights. Distance had major effect but direction its interaction no effect. results suggest that limit below 0.5%, between plots different cultivars would be required. It also indicated Australian mostly self-fertile relatively narrow will ensure self-fertilization production breeding programs.