Nanopriming has been shown to significantly improve seed germination and seedling vigor in several agricultural crops. However, this approach has not been applied to native upland boreal forest species with complex seed dormancy to improve propagation. Herein, we demonstrate the effectiveness of carbon nanoparticles functionalized with carboxylic acids in resolving seed dormancy and improved the propagation of two native upland boreal forest species. Seed priming with carbon nanoparticles functionalized with carboxylic acids followed by stratification were observed to be the most effective in improving germination to 90% in green alder (Alnus viridis L.) compared to 60% in the control. Conversely, a combination of carbon nanoparticles (CNPs), especially multiwall carbon nanoparticles functionalized with carboxylic acid (MWCNT–COOH), cold stratification, mechanical scarification and hormonal priming (gibberellic acid) was effective for buffaloberry seeds (Shepherdia canadensis L.). Both concentrations (20 µg and 40 µg) of MWCNT–COOH had a higher percent germination (90%) compared to all other treatments. Furthermore, we observed the improvement in germination, seedling vigor and resolution of both embryo and seed coat dormancy in upland boreal forest species appears to be associated with the remodeling of C18:3 enriched fatty acids in the following seed membrane lipid molecular species: PC18:1/18:3, PG16:1/18:3, PE18:3/18:2, and digalactosyldiacylglycerol (DGDG18:3/18:3). These findings suggest that nanopriming may be a useful approach to resolve seed dormancy issues and improve the seed germination in non-resource upland boreal forest species ideally suited for forest reclamation following resource mining.

Species composition estimated from forest resource inventory (FRI) was validated using field data collected in 136 stands in Nipissing Forest (Ontario, Canada). FRI-and field-based species composition matched in 54% and 56% of cases using stand count and area coverage, respectively. Possible causes of discrepancy between FRI-and field-based species composition are discussed. Low level of agreement between FRI and field data indicated a need for more extensive studies on FRI validation prior to its use for forest management planning.Key words: forest resource inventory, FRI, forest unit, photo-interpretation, timber cruise RÉSUMÉ La composition en espèces estimée à partir de l'inventaire des ressources forestières (IRF) a été validée au moyen des données de terrain recueillies dans 136 peuplements de la forêt de Nipissing (Ontario, Canada). L'IRF et la composition en espèces sur le terrain ont concordé pour 54% et 56% des cas en utilisant respectivement un décompte des peuplements et le recouvrement en superficie. Les causes probables de différence entre l'IRF et la composition en espèces sur le terrain font l'objet de discussion. Le faible taux de concordance entre l'IRF et les données du terrain indiquent la nécessité d'avoir des études plus exhaustives de la validité de l'IRF avant son utilisation à des fins d'aménagement forestier. IntroductionThe main source of information for forest management planning in Ontario is the Forest Resource Inventory (FRI). In general, a forest resource inventory may be defined as a survey of an area to provide information on the present extent, composition, structure and location of the forest (Gillis and Leckie 1993). In Ontario, the FRI is conducted on a cycle of approximately 20 years. The primary data sources for FRI production are aerial photographs taken at 1:20 000 for northern Ontario and 1:10 000 for southern Ontario. These photographs are used to delineate forest stands and assess other stand attributes through interpretation of photos calibrated with timber cruise plots established subjectively in For personal use only.

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.

No abstract

Application of the nanopriming technique to alleviate seed dormancy has shown promising results in various agricultural crop species. However, there is a dearth of knowledge regarding its potential use in native peatland boreal forest species to alleviate seed dormancy and improve their propagation or vigor for forest reclamation activities. Herein, we demonstrate the use of nanopriming with carbon nanotubes (CNT) to alleviate seed dormancy, improved seed germination, and seedling vigor in two boreal peatland species. Bog birch (Betula pumila L.) and Labrador tea (Rhododendron groenlandicum L.) seeds with embryo or seed coat dormancy were nanoprimed with either 20 or 40 µg/mL CNT, cold stratified at 2–4 °C for 15 days, and allowed to germinate at room temperature. The emerged seedlings’ lipidome was assessed to decipher the role of lipid metabolism in alleviating seed dormancy. We observed significant (p < 0.05) improvement in seedling germination and seedling vigor in seeds primed with multiwalled carbon nanotubes functionalized with carboxylic acids. Phosphatidylcholine (PC 18:1/18:3), phosphatidylglycerol (PG 16:1/18:3), and lysophosphatidylcholine (LPC 18:3) molecular species (C18:3 enriched) were observed to be highly correlated with the increased seed germination percentages and the enhanced seedling vigor. Mechanistically, it appears that carbon nanoprimed seeds following stratification are effective in mediating seed dormancy by remodeling the seed membrane lipids (C18:3 enriched PC, PG, and LPC) in both peatland boreal forest species. The study results demonstrate that nanopriming may provide a solution to resolve seed dormancy issues by enhancing seed germination, propagation, and seedling vigor in non-resource boreal forest species ideally suited for forest reclamation following anthropogenic disturbances.

No abstract

Boreal forests across Canada and other geographic areas globally have vast networks or densities of seismic lines, pipelines, access roads, utility corridors, and multipurpose trails collectively termed “linear disturbances” or “linear features.” Additionally, large areas of disturbances attributed to resource harvesting represent a major anthropogenic impact on the global boreal forest ecosystem. Restoration of these disturbed areas is currently a significant component of global boreal forest management strategies. A key to successful restoration or re-vegetation of these disturbed sites is the availability of highly adaptive native planting materials to grow and establish on the disturbed sites, particularly in varying abiotic stressors or severe environmental conditions. Abiotic stress includes non-living environmental factors, including salinity, drought, waterlogging or extreme temperatures, adversely affecting plant growth, development, and establishment on field sites. Herein, we present the concept of nanopriming native boreal seeds with microgram concentrations of carbon nanoparticles (CNPs) as an effective approach to improve the propagation and vigor of native boreal forest species. Priming refers to the technique of hydrating seeds in solutions or in combination with a solid matrix to enhance the rate at which they germinate and their germination uniformity. Seed priming has been shown to increase seed vigor in many plant species. In this mini-review, we will provide a brief overview of the effect of nanopriming on seed germination and seed vigor in agricultural plants and native boreal forest species, indicating the potential future applications of CNPs on native boreal species for use in forest reclamation or restoration.

No abstract