The minimum distance between two seed production plots to prevent genetic contamination. The contiguity distance depends on the type of crop (about 5 meters for self pollinating crops, 1,500 meters for cross pollinating crops). It also depends on the certification level of the produced seeds: for 'basic' seed, the requirements are more stringent than for 'normal' certified seed.
Synonyms: contiguity constraint
RT: seed contamination risk