Length of cold stratification period affects germination in green alder (Alnus viridis(Chaix) DC. subsp.crispa(Aiton) Turrill) seed collected from northwestern Alberta

Abstract

Alnus viridis (Chaix) DC. subsp. crispa (Aiton) Turrill (Betulaceae), commonly known as green alder or mountain alder, is a boreal shrub used to revegetate disturbed lands because of its ability to persist and flourish in adverse conditions. Cold stratification, as a seed pretreatment, has been effective in breaking the embryo dormancy of green alder seed; however, the recommended duration of cold stratification varies from 0 to 60 d. To determine the optimum time for seed collection and the impact of duration of cold stratification, seed was collected from 3 locations in 2013. One location was chosen for collection of seed over 3 consecutive mo. Seed was subjected to 4 cold stratification treatments at +4 °C (39.2 °F), and we included a non-treated control. Mean germination time was significantly lower with cold-stratified seed than with the non-stratified seed. Green alder seed showed more rapid and uniform germination when cold stratified for 2 wk or 6 wk as compared to 12 wk of stratification or non-stratified. Germination rate of green alder seed was similar over a 3-mo collection period from late summer to fall.

Carbon Nanoparticles Functionalized with Carboxylic Acid Improved the Germination and Seedling Vigor in Upland Boreal Forest Species

“…Buffaloberry has a hard seed coat (physical dormancy), which impedes germination [9,10], as the seed coats are impermeable to water and other nutrients, ultimately preventing the germination of viable seeds [39,68,69]. On the other hand, green alder is inhibited by embryo dormancy [12,70], which is a second category dormancy (morphophysiological dormancy). This dormancy results in low seed germination and stand establishment [70].…”

“…Concomitant with the low seed germination in these species, due to dormancy issues, the germinated seedlings can also have low vigor or growth rates [12]. The seedling vigor index (SVI) can be measured through seedling vigor test [73][74][75] and it is very important to have seedlings with enhanced vigor, or SVI.…”

“…The observation that CNPs enhanced the seedling vigor index indicates that these seeds have enhanced capacity to be able to germinate, get establish, and survive under a range of challenging or stressful environmental conditions. This means that CNPs have the potential to enhance the vigor of native boreal forest seeds during propagation to facilitate plant growth under varied environments and may have applications in boreal forest restoration or reclamation programs [7,8,12].…”

“…These are large (3-12 m tall) shrubs of the genus Alnus. The seeds of green alder are small, 1-2 mm long, light brown, with a narrow encircling wing, and has embryo dormancy [12].…”

“…Cold stratification, incubation with gibberellic acid (hormone priming) and seed coat scarification has been shown to be successful in enhancing the germination rate of rosemary seeds having hard seed coat, embryo, and physiological seed dormancy [12,[37][38][39][40]. This could be a useful approach to apply to seeds such as buffaloberry, which also has multiple seed dormancies.…”