HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (5) Citing Articles via Google Scholar Google Scholar Articles by Springer, T. L. Articles by Aiken, G. E. Search for Related Content PubMed Articles by Springer, T. L. Articles by Aiken, G. E. Agricola Articles by Springer, T. L. Articles by Aiken, G. E. Related Collections Other Forage Crops

FORAGE & GRAZING LANDS

Seed Germination and Dormancy in Eastern Gamagrass

^a USDA-ARS, Southern Plains Range Research Station, 2000 18th Street, Woodward, OK 73801
^b USDA-ARS, Dale Bumpers Small Farms Research Center, 6883 South State Highway 23, Booneville, AR 72927

* Corresponding author (tspringer{at}spa.ars.usda.gov)

Eastern gamagrass [Tripsacum dactyloides (L.) L.] is an important native rangeland species and could be a more widely used perennial pasture grass. Stand establishment, however, is slow, and it can take 3 yr before a full stand is attained. Our objectives were to determine the caryopsis weight distribution, the relationship between caryopsis weight and percentage germination, the role of the cupulate fruit case in seed dormancy, and the force required to open the cupulate fruit case. Caryopses of ‘Iuka’ and ‘Pete’ eastern gamagrass were extracted from the cupulate fruit case by hand, individually weighed, separated into five weight classes, and germinated in a germination chamber. Differences in percentage observed germination and total potential germination at 7 and 14 d were attributed to caryopsis weight (P > 0.05). No caryopsis weight x cultivar interaction occurred, suggesting homogeneity of slopes for cultivars (P > 0.25). An artificial fruit case (band) was fashioned from an extruded plastic tube and a caryopsis placed inside to examine the role of the fruit case in germination. Germination of unbanded caryopses (44.8%) was significantly greater than banded caryopses (6.3%, P 0.01). A lever and fulcrum were used to find the force required to open the fruit case. We concluded that seed dormancy was likely mechanical for these cultivars. Under natural conditions, the integrity of the fruit case must be reduced before germination will proceed normally. Light, alternating temperatures, freezing and thawing, fire, rodents, and soil microorganisms, to name a few, may be involved in the decay of the fruit case.

Abbreviations: RMSE, root mean square error

This article has been cited by other articles:

				L. R. Gibson, E. Z. Aberle, A. D. Knapp, K. J. Moore, and R. Hintz Release of Seed Dormancy in Field Plantings of Eastern Gamagrass Crop Sci., January 31, 2005; 45(2): 494 - 502. [Abstract] [Full Text] [PDF]

				X. Tian, A. D. Knapp, L. R. Gibson, R. Struthers, K. J. Moore, E. C. Brummer, and T. B. Bailey Response of Eastern Gamagrass Seed to Gibberellic Acid Buffered below Its pKa Crop Sci., May 1, 2003; 43(3): 927 - 933. [Abstract] [Full Text] [PDF]