Establishment of Ammophila arenaria (marram grass) from culms, seeds and rhizomes
-
Published source details
van Der Putten W.H. (1990) Establishment of Ammophila arenaria (marram grass) from culms, seeds and rhizomes. Journal of Applied Ecology, 27, 188-199.
Published source details van Der Putten W.H. (1990) Establishment of Ammophila arenaria (marram grass) from culms, seeds and rhizomes. Journal of Applied Ecology, 27, 188-199.
Summary
Because of its natural ability to colonize and stabilize sand dunes, marram grass Ammophila arenaria is often used to control coastal erosion. A laboratory germination experiment was undertaken to assess best seed pre-treatment and germination techniques in order to enhance efficiency of dune stabilization programmes when using marram seed.
Seed collection: On coastal dunes on the island of Voorne, the Netherlands (51.5ºN, 4.05ºE) marram spikes were collected in July 1986, air-dried and threshed to remove the seed.
Experimental design: After 5 months dry storage at 12ºC, batches of 40 seeds (average seed weight 3.6 mg) were placed in Petri dishes on filter paper. The effects of seed pre-treatments, temperature and illumination on germination were examined.
A factorial experiment was undertaken (3 replicates/treatment). Petri dishes with seeds were stored at 4ºC, either moistened with demineralized water ('stratification') or kept dry ('dry cold'), for 0, 2, 3, 5 or 7 weeks. The pre-treated seeds were then exposed to three night/day (16/8 h) temperature regimes: 20/20ºC, 10/20ºC and 20/30ºC. Half of the dishes were wrapped in light-proof bags, whilst the others were open to light during the 8 h period of high temperatures.
In six additional Petri dishes were added 40 seeds (palea and lemma removed). In three dishes, an incision was made in the seed coat without damaging the embryo. Seeds were germinated in light/dark at 8/16 h 20/10ºC.
The dry seeds were moistened immediately before the experiments started, and watered every other day if necessary. Seeds, upon germination, were counted and removed. Moistening and counting of seeds was carried out in green light to protect the seeds of the 'dark' treatment from illumination.
The effect of seed pre-treatment depended on germination temperature. A stratification
period of 5 and 7 weeks increased germination percentage only when the temperature fluctuated daily between 10 and 20ºC. Dry cold storage had no effect on germination. After incision of the seed coat and a germination period of 22 days at 10/20ºC, germination was 94%, compared to 14% in untreated seeds.
All pre-treatments resulted in very low germination percentages at a constant
temperature of 20ºC (c. 18% for 5 weeks stratification pre-treatment; all other pretreatments < 10%). In light and at daily fluctuating temperatures of 20/30ºC,
germination was 80% in 10-15 days, irrespective of pre-treatment of the seed. At a low
daily fluctuating temperature of 10/20ºC, percentage of germination depended on the
effectiveness of pre-treatment of the seed.
Germination in darkness was generally much lower than in light (mostly < 20%). Only those seeds that were stratified for 5 and 7 weeks, and subsequently exposed to fluctuating temperatures of 10 and 20ºC, had a relatively high germination percentage in darkness.
Consclusions: A high rate and percentage of marram seed germination was obtained at fluctuating temperatures in the light. At fluctuating low temperatures, stratification increased germination of seeds. At fluctuating high temperatures, seeds germinated well and stratification gave no improvement. In practice, sowing of marram seed in winter or in early spring will result in a natural stratification.
Note: If using or referring to this published study, please read and quote the original paper, this can be viewed at:
http://links.jstor.org/sici?sici=0021-8901%28199004%2927%3A1%3C188%3AEOAA%28G%3E2.0.CO%3B2-H
Output references
|