GM Crop Database

Database Product Description

19-51A (DD-Ø1951A-7)
Host Organism
Gossypium hirsutum (Cotton)

Herbicide tolerant, sulfonylurea.

Trait Introduction
Agrobacterium tumefaciens-mediated plant transformation.
Proposed Use

Production for fibre, livestock feed, and human consumption.

Product Developer
DuPont Canada Agricultural Products

Summary of Regulatory Approvals

Country Food Feed Environment Notes
United States 1996 1996 1996

Summary of Introduced Genetic Elements Expand

Code Name Type Promoter, other Terminator Copies Form
als acetolactate synthase HT 2 at 1-2 loci Site-directed mutagenesis

Characteristics of Gossypium hirsutum (Cotton) Expand

Center of Origin Reproduction Toxins Allergenicity

Believed to originate in Meso-America (Peruvian-Ecuadorian-Bolivian region).

Generally self-pollinating, but can be cross-pollinating in the presence of suitable insect pollinators (bees). In the U.S., compatible species include G. hirsutum, G. barbadense, and G. tomentosum.

Gossypol in cottonseed meal.

Cotton is not considered to be allergenic, although there are rare, anecdotal reports of allergic reactions in the literature.

Abstract Collapse

Line 19-51a was developed by recombinant DNA techniques to introduce a sulfonylurea tolerant form of ALS gene, which encodes an acetolactate synthase (ALS) enzyme. The ALS enzyme produced in these transgenic cotton lines is a
resistant form of the similar enzyme present in all plants, bacteria and fungi, and thereby confers resistance or tolerance to sulfonylurea herbicides. The ALS gene used in the cotton line 19-51a is a chimeric gene construct that
combines two different ALS genes that both encode herbicide sensitive versions of ALS (Mazur et al. 1987). Through site directed mutagenesis the tobacco ALS genes were altered to confer resistance to sulfonylurea herbicide. This
recombinant ALS gene designated S4-HrA codes for the resistant from of the ALS enzyme that differs in two amino acids, and confers tolerance to sulfonylurea herbicide in the transgenic cotton line 19-51a. The transgenic cotton line
that is the subject of the petition were developed by a widely used technique called Agro-infection which essentially involves using a plant pathogenic strain of A. tumefaciens, and its disarmed plasmid vector (Hoekema et al.
1983; Ooms et al. 1981; Ooms et al. 1982). The chimeric S4-HrA gene was cloned into A. tumefaciens LBA4404. The S4-HrA gene was transformed into cotton plant cells via a "disarmed" Ti-plasmid vector. The variety of cotton
that was used in developing the line 19-51a is the cultivar Coker 312.

Links to Further Information Expand

This record was last modified on Tuesday, February 24, 2015