EurekaMag.com logo
+ Translate

Target moisture content prechill overcomes the dormancy of temperate conifer seeds


, : Target moisture content prechill overcomes the dormancy of temperate conifer seeds. New forests 8(4): 309-321

Temperate conifer seeds are often considered to be shallowly dormant because a dormancy breakage treatment such as incubation of moist seeds at 4 degrees C (prechilling) for 3-6 weeks improves germination. However, longer prechill durations can induce germination during the cold phase. Since the delicate radicles of prematurely germinated seeds are easily damaged and killed during sowing, potential benefits of extended prechilling are unknown. Described here for the first time is a target moisture content (TMC) prechill. In this dormancy breakage method the seeds are chilled at moisture contents high enough for removal of dormancy but low enough to produce surface dry, free flowing seeds that do not germinate during chilling. The method is a simple, effective and practical way to restrict the amount of water available to seeds from the start of a prechill treatment. The TMC prechill was applied to three conifer species, Douglas fir (Pseudotsuga menziesii (Mirbel) Franco), Lodgepole pine (Pinus contorta Douglas), and Sitka spruce (Picea sitchensis (Bongard) Carriere). All three species benefited from the TMC prechill. Extending the prechill period progressively improved germination by widening the range of temperatures over which germination occurred, raising germination capacity at most temperatures and increasing germination rate at all temperatures. The optimum prechill period combining high germination capacity and low mean germination time was 36 weeks for Douglas fir, from 36 to 76 weeks for Lodgepole pine and 36 or 76 weeks for Sitka spruce depending on incubation temperature. None of the seeds of any of the species germinated during the TMC prechill of up to 76 weeks at 4 degrees C.

Order PDF Full Text

Close
Close

Click here to order any other PDF Full Text


Accession: 002549423

DOI: 10.1007/bf00036731

Download PDF Full Text: Target moisture content prechill overcomes the dormancy of temperate conifer seeds


Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:
Close
Close

Related references

Gosling, P.G.; Samuel, Y.; Peace, A., 2003: The effect of moisture content and prechill duration on dormancy breakage of Douglas fir seeds Franco. Seeds of Douglas fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) were initially germinated at six constant temperatures (10-35degreeC), following 0-48 weeks incubation under moist conditions at 4degreeC, i.e. prechill or stratification....

Gosling, P.G.; Samuel, Y.; Peace, A., 2003: The effect of moisture content and prechill duration on dormancy breakage of Douglas fir seeds (Pseudotsuga menziesii var. menziesii Franco). Seeds of Douglas fir (Pseudotsuga menziesii var. menziesii) were initially germinated at six constant temperatures (10-35 degrees C), following 0-48 weeks incubation under moist conditions at 40 degrees C, i.e. prechill or stratification. The best...

Gosling P.G.; Rigg P., 1990: The effect of moisture content and prechill duration on the efficiency of dormancy breakage in sitka spruce picea sitchensis seed. Seeds of Sitka spruce were initially germinated over a range of constant temperatures (10.degree. C-40.degree. C) with and without a three week pretreatment at 4.degree. C on moist filter paper. Ten degrees centigrade was chosen as the optimum tem...

Bartels, H., 1956: The moisture content of conifer seeds.. The moisture content of seeds of Spruce, Pine and Larch in equilibrium with the atmosphere was tested at 10 degrees C., and at relative humidities of 3-97%. Adsorption tests at 4, 25 and 40 degrees were also carried out. The results show that rela...

Mohamed, A.H.; Ejeta, G.; Butler, L.G.; Housley, T.L., 1998: Moisture content and dormancy in Striga asiatica seeds. Freshly harvested Striga asiatica L. seeds will germinate in response to a stimulant only after the passage of time, an after-ripening period, and exposure to moisture at a suitable temperature, a conditioning period. To investigate the role of se...

Carrillo, S.-A.T.lavera, A., I., 1983: Moisture content in conifer seeds and its relation to the percentage of seed germination. Publicacion especial Instituto Nacional de Investigaciones Forestales: (40,pt2) 35-42

Poulsen, Karen Margrethe, 1996: Prolonged cold, moist pretreatment of conifer seeds at controlled moisture content. Cold pretreatment of imbibed seed (stratification) and seed kept at controlled moisture contents for 3-14 weeks was tested for commercial seedlots of Abies nordmanniana, Abies procera, Pseudotsuga menziesii and Picea sitchensis in order to give re...

Gradi, A., 1963: The moisture content of cones and of seeds, a crucial factor in the treatment and storage of conifer seed.. A general discussion of the relation of m.c. of cones to date of collection and seed extraction, and m.c. of seeds in relation to storage conditions. Gives tabulated data on m.c., temperature, and possible duration of storage for a number of conif...

Yasue, T., 1973: Effect of moisture content of seeds and soaking in water on breaking dormancy in indica rice. Dormancy breaking in air-dry rice seeds was promoted by high-temperature treatment, e.g. 30 deg C for 15 days, but the effect of high temperature on dormancy breaking decreased in soaked seeds with a moisture content of 20-30%. Excess drying of se...

Schutz, W., 1997: Primary dormancy and annual dormancy cycles in seeds of six temperate wetland sedges. The effects of dry after-ripening and burial in the soil on seed germination of six temperate wetland Carex spp. (C. canescens, C. cespitosa, C. elongata, C. paniculata, C. pseudocyperus and C. remota) were investigated. Freshly matured seeds, see...