The risk that neighboring plants (weeds or cultivated plants) surrounding a seed production field impose risks of cultivar impurities during seed production. For example because of unwanted cross-pollination or mixing of seeds at mechanical seed harvest. The risk is smaller in case of incompatibility or male sterility, and declines sharply with distance. The risk of cultivar impurities declines in the sequence: wind pollinating crop, insect pollinating crop, self-pollinating crop.
Synonym: seed contaminatio
RT: quality seed
RT: contiguity constraint