TRANSGENIC TURFGRASSES A unique tool to advancing the development of new turfgrass varieties. by ARTHUR P. WEBER

URfundamental understanding will kill corn- of the biological sciences stands borer pests that Oready to explode, and the bene- try to eat the fits to be derived loom large. For plant. golfers, biotechnology promises to The derived accelerate the improvement of turfgrass benefits have not species using genetic engineering tech- occurred without niquesY) Genetic Modification (GM), environmental Le. the splicing of genes from one orga- concerns. In the nism to another unrelated organism to wake of these combine traits that would otherwise genetic advances be highly unlikely to occur together, are reports that is a natural succession to the earlier com engineered realization and success of the USGA to carry the Bt Green Section Research Program, a toxin might harm goal of which is to "develop turfgrasses butterflies or with enhanced stress tolerance and other non-target reduced supplemental water require- insects and ments, pesticide use and costs." wildlife. Contro- Among the most desirable charac- versy relating to teristics of such GM turfgrasses would human and be: (2) animal health 1. Ability to survive high and low over the long temperature extremes. term derives from A more modern means of micro engineering turfgrass plants 2. Reduced need for pesticides by concerns that involves the use of a gene gun. Selected DNA is fired into living increasing resistance to disease, insects, plants with genes plant cells using an explosive charge to insert the DNA into the host chromosomes. The cells are regenerated into whole plants, nematode, and weed encroachments. from viral patho- hopefully carrying the new gene. 3. Tolerance of intensive traffic. gens might 4. Reduced requirements for mow- combine with ing, irrigation, and fertilization. other viruses to create new viral strains. and older of the technologies uses the 5. Tolerance of non-potable water. It is thought by some groups that the bacterial species Agrobacterium tuma- 6. Stability of inherited charac- transgenic plants could create new taciens to carry the gene of interest teristics. allergies or exacerbate existing ones, into the host plant. Agrobacterium, a 7. Tolerance of acid, alkaline, or such as the recent claims of increased microorganism that causes plant dis- saline soils. allergic reactions to genetically altered ease (Le., galls) and has been known 8. Tolerance of smog and other soybeans. since the turn of the 20th century, pollutants. Notwithstanding, breakthroughs in possesses its own genetic engineering 9. Increased shade tolerance. genetics have made it possible to system. In nature, the bacterium sends Transgenic biotechnology, although improve crop plants and farm produc- its own genes into the infested host and still in its infancy, has already become tivity in ways conventional breeders inserts them into plant chromosomes. a significant commercial reality. Genes could only dream about. The possibili- Researchers take advantage of this taken from other organisms can be ties are endless. With conventional means of transforming plants by infect- spliced into food plant DNA, e.g. com, breeding, it can take seven or more ing them with laboratory-developed soybeans, and canola. Herbicide toler- years to produce a new plant that may Agrobacterium mutants whose dis- ance to products such as Roundup be only marginally superior to its pre- ease-carrying genes were replaced with (glyphosate) has been conferred using decessors. Genetic modification allows specifically chosen DNA. In effect, the genetic engineering so weeds can be researchers to insert a wide array of bacterium then acts as a microengineer, controlled without harming the crops. new genes into a plant and make doing all the work. Com seed, by carrying a gene derived improvements more efficiently. The second, more modem means of from the bacterium Bacillus thurni- Two main methods prevail for micro engineering uses a gene gun that giensis (Bt) produces the Bt toxin that genetic engineering in plants: The first was developed, in part, to allow for the

MARCH/APRIL 2000 31 Traditional breeding methods can take ten years and beyond to successfully bring a new turfgrass variety to market. Genetic engineering techniques can produce significant improvements beyond a traditional breeding program. transformation of plants that cannot be that control complex responses, and inserted into existing creeping bent- infected with Agrobacterium. In using they will create an opportunity to grass varieties to ascertain if resistance the gene gun, selected DNA, coated assign functional information to genes to various stresses can be improved. onto gold or platinum microparticles, is of otherwise unknown function. This Early results indicate that various genes fired into living plant cells, either cell information will ultimately help con- (e.g., elm chitinase, proteinase inhibi- cultures or embryos, using an explosive ventional plant breeding programs be- tor, glufosinate resistance, and manni- charge. The cells are punctured by the come more efficient in developing new tol dehydrogenase) can be successfully microbullets, and the DNA enters the varieties. inserted into the bentgrass genome. nucleus and then inserts into the host Toward these ends, the USGA Green However, with the exception of the chromosomes. Section Turfgrass and Environmental glufosinate resistance gene, improved The cells, those infected by Agro- Research Program, among other con- stress tolerance has been somewhat bacterium or shot by the biolistic gun, ventional and biotechnological turf- limited. The genes can be found in the are regenerated into whole plants, grass breeding methods, has committed transformed bentgrass plants but do which then carry the new gene or genes $835,000 over the next five years to the not significantly improve disease resis- of interest. These plants are tested, following university studies already tance or increase the amount of man- cloned, and ultimately can provide the underway: nitol to help with drought and salt seed for a new plant variety. "A Multigene-Transfer Strategy to tolerance. One of the new and exciting experi- Improve Disease and Environmental "Hybrid Bermudagrass Improvement mental approaches for discovering the Stress Resistance in Creeping Bent- by Genetic Transformation," North function of genes is DNA microarrays. grass," Michigan State University, Carolina State University, Rongda Qu, From them, extensive databases of Mariam R. Sticklen, Start Date 1998, 3 Start Date 1998, 3 years, total funding quantitative information can be ob- years, total funding $75,000. $75,000. tained about the degree to which genes This study focuses molecular solu- The research is developing a genetic respond to pathogens, pests, drought, tions to the biotic (i.e., pest) problems engineering protocol for hybrid ber- cold, salt, growth regulators, herbi- and abiotic (Le., heat, humidity, etc.) mudagrass varieties. Bermudagrass has cides, and other agricultural chemicals. problems associated in the manage- been more difficult to work with due These gene expression databases will ment of creeping bentgrass turf. A to problems producing viable plant provide novel insights into the genes series of available genes has been embryos, and eventually healthy plants,

32 USGA GREEN SECfION RECORD from tissue culture callus. Once a ing quality playing surfaces by improv- Despite some of the environmental reproducible technique is developed, ing creeping bentgrass through genetic and health concerns, research efforts research efforts will focus on inserting transformation. The work has concen- should be supported to ascertain how genes that confer nematode resistance trated on important bentgrass varieties turfgrass improvement efforts could into the bermudagrass clones. and selections developed for golf use the new genetic engineering tech- "Bermudagrass Cold Hardiness: greens in the Northeast. New bentgrass niques. Propelled by the skillful appli- Characterization of Plants for Freeze cultivars with improved stress tolerance cation of genetic modification tech- Tolerance and Character of Low-Tem- and disease resistance are under devel- niques, the dramatic improvement of perature Induced Genes," Oklahoma opment through a combination of golf course turfgrasses, as part of a State University, Charles M. Taliaferro, molecular and conventional plant comprehensive plant revolution, is now Start Date 1998, 5 years, total funding breeding efforts. The effectiveness of well underway. Ultimately, it will be a $125,000. genetically engineered herbicide resis- combination of new genetic modifica- This research will reduce the risk of tance in creeping bentgrass was tion tools with existing conventional freeze injury to bermudagrass grown in demonstrated in several field tests, and plant improvement techniques that temperate regions. The project is accu- the trait is now incorporated into a new will provide turfgrass varieties with en- rately assessing the freeze tolerance of cultivar. There are 50 new transgenic hanced stress tolerance and. reduced bermudagrass cultivars, isolating genes lines of creeping bentgrass expressing supplemental water requirements, responsible for enhanced freeze toler- one of five potential disease resistance pesticide use, and costs. ance, and enhancing knowledge of the genes. fundamental mechanisms associated "Transformation of Bermudagrass References with cold tolerance. Substantial prog- for Improved Fungal Resistance," (l)Sticklen, M. B., & Kenna, M. P., 1998, ress toward isolating the characterizing Oklahoma State University, Michael P. Turfgrasses Biotechnology, Ann Arbor cold regulated proteins responsible for Anderson, Start Date 1998, 5 years, Press, Chelsea, Michigan. improved freeze tolerance in bermuda- total funding $125,000. (2)Kenna,M. P., & Snow, J. T., 1999, USGA grass was achieved. Measured gene The long-term goal of this project is Turfgrass & Environmental Research activity increases of 75 to 100 percent to improve bermudagrass resistance to Program. in crown and root tissues occurred spring dead spot using gene transfor- after 24 hours of exposure to cold mation. The disease is active in the fall temperatures. and early spring when temperatures are "A Turfgrass Genome Project: Inte- cool and moisture is plentiful. A genetic ARTHUR P. WEBER, a semi-retired gration of Cynodon Chromosomes transformation system was developed chemical and nuclear engineer, has been an active member of the USGA Green with Molecular Maps of Cereals," for a forage-type bermudgrass because Section Committee since 1984. A longtime University of Georgia, Andrew H. it had previously demonstrated superior Green Committee chairman, he was the Paterson, Start Date 1999,5 years, total growth and plant regeneration poten- principal author behind the Old Westbury funding $125,000. tial in tissue culture. Efforts to identify Golf and Country Club (NY) Code of The research project is producing the an anti-fungal protein antagonistic to Environmental Conduct, a leading set of first primary molecular map for the spring dead spot are making progress. principles for golf course maintenance. chromosomes of bermudagrass. This information will be compared with molecular maps of the major cereal crops in order to gain access to the wealth of genetic information pro- duced by scientists around the world. The map will be useful for investigating many aspects of turfgrass population biology and genetics, and provide a molecular conduit for turf improve- ment. Significant progress on charac- terizing DNA from bermudagrass and developing molecular markers was accomplished during the last year. The focus in the future will turn to full- scale genetic mapping and identifying quantitative traitloci (QTLs) of imp or- tant turfgrass characteristics. "Development of Improved Bent- grass Cultivars with Herbicide Resis- tance, Enhanced Disease Resistance, and Abiotic Stress Tolerance through Biotechnology," Rutgers University/ Cook College, Faith Belanger, Start Date 1998, 5 years, total funding $250,000. A gene resistant to the herbicide glyphosate was successfully inserted into the plant This project will help conserve golf on the right. Plants without the inserted gene react with the results on the left when course natural resources while provid- treated with glyphosate.

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