Germplasm Ownership: Related Corn Inbreds

Corn (Zea mays L.) germplasm ownership methods are unwieldy and limit progress. Agronomic performance in hybrids better identifies inbreds for distinctness, i.e., independent varieties (IVs) or for dependency, i.e. essentially derived varieties (EDVs) than do molecular methods alone. Our objectives were to assess hybrid agronomic performance of some popular, closely related inbreds on the basis of molecular methods, and to offer thoughts on developing inbreds and on germplasm ownership. Significant agronomic differences were detected between the following: two hybrids in the same genetic group on the basis of 21 isozymic loci; two closely related inbreds (B73 and LH119) with 88.6% (62/70) RFLP (restriction fragment length polymorphism) similarity; and two closely related inbreds (Mo17 and LH51) with 88.2% (60/68) RFLP similarity. We suggest raising dependency standards for patenting inbreds to 90% or more, allowing the right to use and also paying a small royalty for only 5 yr on EDVs to the owner of the IV, and maintaining a research exemption to provide elite inbreds for developing new inbreds and experimental hybrids to all breeders. This will help maintain genetic gain for corn grain yield and serve the common good.