(a) Corn.
  (1) Hybrid corn is seed to be planted for any use except seed. It may be any one of the following:
    (A) a single cross, i.e., a first generation of cross between two inbred lines;
    (B) a double cross, i.e., the first generation of a cross between two single crosses;
    (C) a three way cross, i.e., the first generation of a cross between a single cross and an inbred line; or
    (D) a top cross, i.e., the first generation of a cross between an inbred line and an open pollinated variety, or the first generation of a cross between a single cross and an open pollinated variety.
  (2) To be eligible for certification, a foundation single cross used to produce double, three-way, or top crosses, must be produced from approved inbred lines whose source assures their identity.
  (3) Inbred lines.
    (A) For an inbred line, to be eligible for certification, it must be from an identifiable source and it must be approved by the certifying agency.
    (B) An inbred line used as a pollinator in a foundation single cross isolation may be certified, provided all the seed parents in the isolated field are inspected for certification and meet all field requirements for certification.
    (C) The following classes of seed are recognized.
      (i) Only the class "certified" is recognized in hybrid corn.
      (ii) Hybrid corn must be produced from foundation seed that has been field inspected.
      (iii) A foundation single cross shall consist of the first generation hybrid between two inbred lines to be used in the production of double, three-way or top crosses. A fertility restoring line may be substituted for its nonrestoring counterpart.
      (iv) An inbred line must be relatively true- breeding strain of corn resulting from at least five successive generations of controlled self-fertilization or a back crossing to a recurrent parent with selection or its equivalent.
    (D) When a specific genetic factor(s) is added to an inbred line, the line must have been back-crossed to its recurrent parent at least five generations. The line must be homozygous for the specific genetic factor(s) except for the pollen restoration factor(s).
    (E) For a recovered pollen restorer inbred line, selection must be relative to a specific cytoplasmic male sterile source.
    (F) Proof of the genetic nature of a recovered line will be supplied by the originator.
(b) Sorghum.
  (1) Male sterile seed stock.
    (A) A male sterile seed stock is one to be planted for use as a seed parent in the production of hybrid sorghum seed.
    (B) The pollinator for the production of a male sterile seed stock must originate from seed stocks which are designated specifically for the use as a pollinator of the male sterile seed stock and must not be more than two generations removed from stocks in which plants were individually checked for their ability to maintain high sterility.
    (C) Male sterile seed stock must represent a parent of a specific combination that has been approved by the State Seed and Plant Board.
    (D) The name under which any male-sterile seed stock shall be certified shall be the same as the designation given by the originator or originating agency.
    (E) The entire acreage in an isolated seed production plot or in a given seed production field must be eligible and must be inspected.
  (2) Pollinator lines (B & R).
    (A) A pollinator line is one to be planted for use as a pollen parent in the production of male sterile seed stocks or hybrid sorghum seed.
    (B) B Lines are defined as maintainer pollinator lines for use in the production of male sterile seed stocks.
    (C) R Lines are defined as restorer pollinator lines used in the production of commercial hybrids.
    (D) A pollinator line, to be eligible for certification, must be from a source such that its identity may be assured. A pollinator line must represent a parent of a specific combination that has been approved by the State Seed and Plant Board.
    (E) The name under which any pollinator line shall be certified shall be the same as the designation given by the originator or the originating agency.
    (F) The parental stock for the production of a pollinator line must originate from seed stocks which are designated specifically for use as a pollinator.
    (G) The entire acreage in an isolated seed production plot or in a given seed production field must be eligible and must be inspected.
  (3) Hybrid (commercial).
    (A) A certified hybrid sorghum (commercial) is one to be planted for any use except seed.
    (B) Hybrid sorghum (commercial) planting seed, to be certified, must be produced from foundation seed stocks approved by the State Seed and Plant Board, meeting the requirements of the specific standards for male sterile seed stock and the specific standards for pollinator lines (B & R) except for hybrid sorghum (commercial), approved by the State Seed and Plant Board as a "closed pedigree," in which case the male sterile and pollinator line (B & R) will be inspected on the basis of a complete breeder plant description using the tolerances set forth in this standard at the time the hybrid sorghum (commercial) seed is being produced.
    (C) The name under which any hybrid sorghum (commercial) is certified, shall be the same as the designation given by the originator or the originating agency and must represent a specific combination that has been approved by the State Seed and Plant Board.
    (D) The pollinator for the production of a hybrid sorghum (commercial) must originate from seed stock which is designated specifically for use as a pollinator of the hybrid.
    (E) The entire acreage in an isolated seed production field must be eligible and must be inspected.
(c) Hybrid sunflower.
  (1) The class "foundation" shall be recognized for the female seed parent and male pollinating parent used for the production of commercial hybrids.
  (2) A commercial hybrid is one to be planted for any use except seed production. Only the class "certified" is recognized in hybrid sunflower.
  (3) A commercial hybrid to be certified must be produced from foundation seed stock approved by the certifying agency.
  (4) A female seed parent and male pollinating parent is one to be planted for use in the production of hybrid sunflower seed.
  (5) The name under which any seed parent, male pollinating parent or commercial hybrid is certified, shall be the same as the designation given by the originator or originating agency.
  (6) The entire acreage in any isolated seed production plot or in a given seed production field must be eligible and must be inspected.
  (7) Pollen rows must be identified by stakes at each end.

Source Note: The provisions of this §10.18 adopted to be effective September 2, 1996, 21 TexReg 7955.