Seed enhancement: getting seeds restoration‐ready

Self Cite

The growing demand for native seeds in ecological restoration and rehabilitation, whether for mining, forest, or ecosystem restoration, has resulted in a major global industry in the sourcing, supply, and sale of native seeds. However, there are no international guidance documents for ensuring that native seeds have the same standards of quality assurance that are regular practice in the crop and horticultural industries. Using the International Principles and Standards for the Practice of Ecological Restoration as a foundation document, we provide for the first time a synthesis of general practices in the native seed supply chain to derive the Principles and Standards for Native Seeds in Ecological Restoration (“Standards”). These practices and the underpinning science provide the basis for developing quality measures and guidance statements that are adaptable at the local, biome, or national scale. Importantly, these Standards define what is considered native seed in ecological restoration and highlight the differences between native seeds versus seeds of improved genetics. Seed testing approaches are provided within a logical framework that outline the many different dormancy states in native seed that can confound restoration outcomes. A “pro‐forma” template for a production label is included as a practical tool that can be customized for local needs and to standardize reporting to end‐users on the level of seed quality and germinability to be expected in a native seed batch. These Standards are not intended to be mandatory; however, the guidance statements provide the foundation upon which regulatory approaches can be developed by constituencies and jurisdictions.

Section: Box 1 Seed Dormancymentioning

confidence: 99%

International principles and standards for native seeds in ecological restoration

Pedrini

Dixon

2020

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“…Seed coatings (e.g. pelleting and encrusting) can further improve uniformity of seed size and shape and precision in seed metering and placement in the soil (Pedrini et al 2020a). Seed coatings can also provide nutrients, inocula, or improved microsite conditions for sown seeds, particularly for seedings on arid lands or degraded soils such as found in post‐mined areas.…”

Section: Seeding Requirementsmentioning

confidence: 99%

Seed use in the field: delivering seeds for restoration success

Shaw

Barak

Campbell³

et al. 2020

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Seed delivery to site is a critical step in seed‐based restoration programs. Months or years of seed collection, conditioning, storage, and cultivation can be wasted if seeding operations are not carefully planned, well executed, and draw upon best available knowledge and experience. Although diverse restoration scenarios present different challenges and require different approaches, there are common elements that apply to most ecosystems and regions. A seeding plan sets the timeline and details all operations from site treatments through seed delivery and subsequent monitoring. The plan draws on site evaluation data (e.g. topography, hydrology, climate, soil types, weed pressure, reference site characteristics), the ecology and biology of the seed mix components (e.g. germination requirements, seed morphology) and seed quality information (e.g. seed purity, viability, and dormancy). Plan elements include: (1) Site treatments and seedbed preparation to remove undesirable vegetation, including sources in the soil seed bank; change hydrology and soil properties (e.g. stability, water holding capacity, nutrient status); and create favorable conditions for seed germination and establishment. (2) Seeding requirements to prepare seeds for sowing and determine appropriate seeding dates and rates. (3) Seed delivery techniques and equipment for precision seed delivery, including placement of seeds in germination‐promotive microsites at the optimal season for germination and establishment. (4) A monitoring program and adaptive management to document initial emergence, seedling establishment, and plant community development and conduct additional sowing or adaptive management interventions, if warranted. (5) Communication of results to inform future seeding decisions and share knowledge for seed‐based ecological restoration.

“…Seed cleaning (also known as processing, or conditioning) is the removal of inert matter, seeds of undesirable species, and non‐viable seeds from a seed lot (or batch) (Houseal 2007; Bonner et al 2008; Bartow 2015). Appropriate seed cleaning reduces potential vectors for pathogens and pests, reduces seed lot volume, facilitates moisture management (important for viability maintenance), reduces storage costs, increases seed lot purity and quality, simplifies seed handling, improves flowability through mechanized equipment, and allows for the application of seed enhancement treatments such as seed coating (Pfaff et al 2002; Houseal 2007; ENSCONET 2009; Bartow 2015; Guzzomi et al 2016; Pedrini et al 2020b).…”

Section: Seed Cleaningmentioning

confidence: 99%

“…Historically, vigor tests have only been recommended for species that germinate readily. Recently, vigor tests have become useful in evaluating the effectiveness of seed enhancement treatments such as priming and coating (Pedrini et al 2020b). The types of vigor tests include cold test, accelerated aging, and radicle emergence (Association of Official Seed Analysts 2018; International Seed Testing Association 2020).…”

Section: Native Seed Quality Testing Recommendationsmentioning

confidence: 99%

Ensuring seed quality in ecological restoration: native seed cleaning and testing

Frischie

Miller

Pedrini

et al. 2020

Self Cite

Seeds are a critical and limited resource for restoring biodiversity and ecological function to degraded and fragmented ecosystems. Cleaning and quality testing are two key steps in the native seed supply chain. Optimizing the practices used in these steps can ensure seed quality. Post‐collection handling of seeds can have a profound impact on their viability, longevity in storage, and establishment potential. The first section of this article describes seed cleaning, outlines key considerations, and details traditional and novel approaches. Despite the growth of the native seed industry and the need for seed quality standards, existing equipment and standards largely target agricultural, horticultural, and commercial forestry species. Native plant species typically have complex seed traits, making it difficult to directly transfer existing cleaning and quality standards to these species. Furthermore, in ecological restoration projects, where diversity is valued over uniformity crop standards can be unsuitable. We provide an overview and recommendations for seed quality testing (sampling, purity, viability, germinability, vigor), identity reporting, and seed transfer as well as highlight the need to implement internationally recognized standards for certification for native seeds. Novel and improved cleaning and testing methods are needed for native species from a range of ecosystems to meet the challenges and goals of the United Nations Decade on Ecosystem Restoration. The guidelines outlined in this article along with others in the Special Issue of Restoration Ecology “Standards for Native Seeds in Ecological Restoration” can serve as a foundation for this critical work.