Louisiana Administrative Code › Title 7 - AGRICULTURE AND ANIMALS › Part XIII - Seeds › Chapter 7 - Certification of Specific Crops/Varieties › Subchapter B - Grain and Row Crop Seeds › Section XIII-755 - Sweet Potato Certification Standards (Virus and Non Virus-Tested)

Current through Register Vol. 50, No. 6, June 20, 2024
A. The standards
				  for certification of virus-tested and non virus-tested sweet potatoes are the
				  general seed certification standards for roots, plants and cuttings as adopted
				  in Subchapter B of this Part and the following specific standards.
B. The following definitions apply to this
				  Section only.
Certified G0 Plant
-a plant grown in a
					 greenhouse and which has been produced by a certified greenhouse grower from a
					 foundation plant.
Daughter Plant
-a plant produced by
					 cuttings from a mother plant.
Foundation Plant
-a plant that has been
					 produced by the LAES from a virus-tested nuclear stock plant recognized by LDAF
					 if the plant is grown in a greenhouse under strict isolation in a screen cage
					 in which only plants that are virus-tested are grown.
Mericlone
-plants clonally propagated from
					 a single meristem tip. For example,
mericlone
B-63 includes
					 all plants descended from the sixty-third meristemtip culture derived from the
					 variety Beauregard.
Micropropagated
-plant multiplication in
					 vitro. The process includes many steps; stock plant care, explant selection and
					 sterilization, media manipulation to obtain proliferation, rooting,
					 acclimation, and growing on. Sweet potato is most commonly micropropagated in
					 tissue culture by aseptic transfer of stem segments containing 1-3 nodes to
					 sterile tissue culture medium.
Mini-Roots
-storage roots produced on
					 plants grown in certified G0 greenhouses that may be used to establish
					 certified G2 field plantings.
Mother Plant
-a plant obtained from
					 LAES.
Nuclear Stock Plant
-plant that is derived
					 from Source Seed and which has been micropropagated, virus-tested, is
					 apparently free of other pests, and has been evaluated in field test for
					 trueness to variety.
Source Seed
-material entering the LAES
					 seed program obtained by methods acceptable to LDAF.
Symptomatic Plant
-a plant that shows an
					 indication or symptom of a disease, mutation, pest, virus, or other problem
					 that may affect sweet potato production.
Vine Cutting
-a section of a vine,
					 preferably 10-12 inches in length, capable of being transplanted.
Virus-Tested
-a plant that has been
					 previously tested for the presence of viruses by grafting a sweet potato shoot
					 to the Brazilian morning glory (
Ipomoea setosa
) on at least
					 three separate occasions and by at least one negative assay by the DNA and PCR
					 assay for sweet potato geminiviruses using the Li et al. method (Li, R., Salih,
					 S., and Hurtt, S. 2004. Detection of geminiviruses in sweet potato by
					 polymerase chain reaction. Plant Dis. 88:1347-1351).
C. Plant Generations
1. Mother plants may be cut repeatedly for no
				  more than five months and the cuttings propagated to produce daughter
				  plants.
2. Daughter plants may be
				  cut repeatedly for no more than five months and the cuttings propagated to
				  produce additional daughter plants. All daughter plants shall be designated as
				  certified G0 and may be used to establish certified Gl field
				  plantings.
3. All plants, vine
				  cuttings and roots produced from mini-roots shall be designated as certified
				  G2.
4. Certified G1 (field
				  generation 1) plantings will be established from certified G0 plants. Vine
				  cuttings may be taken repeatedly from this original G1 planting, to establish a
				  second G1 planting. Vine cuttings may be taken repeatedly from the second G1
				  planting to establish a third G1 planting. No additional plantings may be
				  established from this third G1 planting. All vine cuttings and roots produced
				  during this first year of field production shall be designated as certified
				  G1.
5. Certified G2 (field
				  generation 2) plantings will be established from certified G1 stocks. Vine
				  cuttings may be taken repeatedly from this original G2 planting, to establish a
				  second G2 planting. Vine cuttings may be taken repeatedly from the second G2
				  planting, to establish a third G2 planting. No additional plantings may be
				  established from this third G2 planting. All vine cuttings and roots produced
				  during this second year of field production shall be designated as certified
				  G2.
6. Certified G3 (field
				  generation 3) plantings will be established from certified G2 stocks. Vine
				  cuttings may be taken repeatedly from this original G3 planting, to establish a
				  second G3 planting. Vine cuttings may be taken repeatedly from the second G3
				  planting to establish a third G3 planting. No additional plantings may be
				  established from this third G3 planting. All vine cuttings and roots produced
				  during this third year of field production shall be designated as certified
				  G3.