(Simpson and Ogorzaly 1995, Taliaferro 1995). Consequently, strategies have been sought to improve the performance of this plant under a variety of environmental stresses (Cisar et al. 2000).
Cynodon dactylon is also considered one of the world’s worst weeds (Holm et al. 1977), especially in the tropics and subtropics but also in warmer parts of temperate zones. It is an especially important weed of sugarcane, cotton, and corn. It is a troublesome weed in some parts of the United States; for example, in the West it has been described as “posing a serious threat to crop production and turf management” (Ball et al. 2000). The species is wind pollinated and reproduces by seed but more frequently by vegetative spread of plant parts (stolons and rhizomes).
Since 1999 APHIS has received and acknowledged the eligibility of five notifications from Rutgers University for New Jersey field tests of salt- and drought-tolerant bermudagrass. One of the notifications (99-308-10n) is discussed here.
The notification application names the transformed organism as a bermudagrass hybrid, Cynodon dactylon × C. transvaalensis. The application also describes the mode of transformation (in this case, particle bombardment). The added genes also are detailed. The gene inserted to confer possible drought and salt tolerance was betaine aldehyde dehydrogenase from Atriplex hortensis, a plant species that shows considerable drought and salt tolerance. The promoter for that gene was maize ubiquitin. The terminator was nopaline synthase polyadenylation sequence from Agrobacterium tumefaciens. The plants also are transgenic for a selectable marker, hygromycin B phosphotransferase from the bacterium Streptomyces hygroscopicus with a rice actin promoter and a 35s polyadenylation sequence from cauliflower mosaic virus (CaMV) for a terminator. The specific planned introduction was a field test at Rutgers University Horticulture Farm II. The applicant certified that the regulated article “will be introduced in accordance with the eligibility criteria and performance standards set forth in 7 CFR 340.3.”
Because the primary concern for the notification process is containment, adherence to performance standards is important. And because the transformed organism is closely related to an important weed and contains transgenes that might confer an advantage to that weed, that containment is not just an academic exercise. Indeed, the applicant took containment very seriously when reporting his containment procedures to APHIS in a letter dated March 26, 2001. The transformed organism is the variety “TifEagle” (Hanna and Elsner 1999), used primarily as a turfgrass for putting greens in golf courses. The variety is a triploid bermudagrass that is both male and female sterile. Thus, dispersal by pollen and seed does not occur. The field test involved a comparison of the performance