General requirements

The following genetic standards are applicable for the production of parental lines and hybrids of wheat produced in alternating strips of cytoplasmic male-sterile seed parent and a fertility restorer line. 1. Eligibility requirements for varieties. Standards applicable to wheat varieties apply to the production of pollinator lines. 2. Definition of parental types. a. Maintainer (B-line). A line with normal fertile cytoplasm which is used as a pollinator to increase the seed parent. b. Seed parent (A-line). A cytoplasmic male-sterile line (CMS), which is genetically identical to the maintainer line that when pollinated by a restorer, produces hybrid seed. c. Restorer (R-line). Any male fertile line possessing nuclear restoration genes used as a pollinator in the production of commercial hybrid seed. 3. Eligible seed classes. a. Only the certified class is recognized in the production of commercial hybrid seed. A commercial hybrid is planted for any use except for seed production. To be certified, a commercial hybrid must be produced from foundation class seed stocks. These seed stocks must consist of male steriles, inbred lines, and/or hybrids. b. Only the foundation class is recognized for parental lines.