Submitted to: Eastern Native Grass Symposium
Publication Type: Proceedings
Publication Acceptance Date: 5/1/2000
Publication Date: 7/1/2000
Citation: RHODEN, E.G., RITCHIE, J.C., KRIZEK, D.T., FOY, C.D. VEGETATIVE PROPAGATION OF EASTERN GAMAGRASS: EFFECTS OF ROOT PRUNING AND GROWTH MEDIA. EASTERN NATIVE GRASS SYMPOSIUM. 2000. Interpretive Summary: Eastern gamagrass is being promoted for forage and erosion control. The difficulties in establishment from seed make the use of vegetative propagation attractive. Using vegetative propagation in the establishment of eastern gamagrass would be an effective tool in producing large numbers of genetically identical plants. This study showed that vegetative propagation with one, two, three, and four roots on a culm was possible. Jiffy Mix and Turface appear to be excellent growth media to achieve rapid development. Tatum soil, which is very acid and adheres to the culms, had excellent survival rates of plants but slow development. Therefore, methods that combine both media, or development of a medium that gives those qualities, should be explored. The chances of successful survival of propagated material lie in the rapid development of roots on both the propagated culm and the successive tillers. Factors such as the carbohydrate reserves of the transplanted culm, temperature, nutrient status, and moisture will affect the successful survival of the propagated material. Coupled with the rate of vegetative propagated material survival is the need to develop equipment that can easily plant these materials in the field. Without such equipment, large-scale vegetative propagation would not be a successful tool to increase eastern gamagrass acreage.
Technical Abstract: Eastern gamagrass is being investigated for forage and erosion control. Methods of vegetatively propagating this crop are being explored to obtain cloned planting material. A 16-week greenhouse study was conducted at ARS facilities in Beltsville, Maryland, to determine the minimal number of roots and growth media needed for the successful propagation of eastern gamagrass. The treatments consisted of four growth media (Jiffy mix, a composted soil, Tatum soil, and Turface) and severity of root pruning (one, two, three, or four roots remaining on the culm). Plant survival rates ranged from 16.7% in the composted soil to 75.0% for Tatum soil. Tiller number, plant height, and foliage dry weights were greatest for plants grown in Jiffy mix. Foliage dry weights for plants grown in Tatum soil, Turface, composted soil, and Jiffy mix averaged 3.9, 12.3, 23.8, and 34.2 g/plant, respectively. Although eastern gamagrass plants grown in Tatum soil had the highest survival rates, these plants were the shortest, had the lowest plant dry weights, and the fewest number of tillers. After 16 weeks, plants obtained from culms with two or three roots transplanted into Jiffy mix had the overall best appearance of all root pruning/growth media treatments. It is feasible to vegetatively increase eastern gamagrass by transplanting a minimum crown tissue into a porous, well-aerated growth medium.