Those who are new to the webtool may have questions about the underlying concepts, the terminology used, and the tool’s benefits and capabilities. Here are some of the most frequently asked questions.
Restore and Renew webtool FAQs
The size of a genetic collection area is determined by gene flow. High gene flow across the landscape results in very large genetic collection areas, whereas low or restricted gene flow results in smaller genetic collection areas.
Gene flow in plants is influenced by many factors, including pollen and seed dispersal mechanisms, plant traits such as flowering time and mating systems, environmental factors such as climate, and geography and topographic features such as mountains or rivers which may act as geographic barriers to gene flow.
Given the range of factors that influence gene flow and their interactions, it is not always possible to infer the cause of a particular genetic collection area looking like it does. This does not influence the application of guidance given that sourcing from within a genetic collection area replicates or reinstates natural gene flow, irrespective of the factors influencing natural gene flow.
When future climate matched areas do not occur within a genetic collection area, we recommend maximising adaptive potential by sourcing plants widely across the genetic collection area. You may also consider sourcing up to 20% of individuals from outside the genetic collection area and within the projected future climate region.
Sourcing material from outside of a genetic collection area may result in mating between individuals that possess significant genetic differences. The consequences of mating between genetically dissimilar individuals is typically unpredictable, but may include outbreeding depression, a reduction of fitness of some progeny because of various kinds of genetic incompatibilities between the genes from the different populations.
There may be situations where material from outside of a genetic collection area is included in a seed sourcing strategy, for example to incorporate future climate matched material or overcome low genetic diversity. In such situations, the risk of can be reduced by minimising the proportion of material sourced from outside the genetic collection area (<20%) so that the majority is from within.
The Restore and Renew webtool can guide supplementary planting to enhance the genetic diversity and climate-readiness of existing restoration sites. Use as you would for a new restoration site and consider the provenance of material already planted when designing your seed sourcing strategy.
The webtool identifies genetic collection areas for 100 native plant species so far. New species are added regularly. If there are particular species you are interested in you can contact us to see if they are in preparation or to enquire regarding how you can help add new species to the webtool.
In the absence of genetically informed seed sourcing guidance, resort to generalised seed sourcing guidance, keeping in mind the limitations.
The Restore and Renew webtool identifies site-specific guidance. If you are restoring more than one site, or are developing a regional seed sourcing strategy, first check whether your target area aligns with an intensive project. If so, the intensive project report may provide useful guidance, including genetically optimised seed sourcing strategies. If your target sites are not covered by an intensive project, work though the webtool for each site. If the sites are close or in similar environments, the genetic and climatic guidance may be consistent, and a single seed sourcing strategy may be suitable. If sites are more distant sites or in different environments, multiple site-specific seed sourcing strategies may be needed.
A genetically optimised seed sourcing strategy identifies the number of individuals and sites that seed should be collected from within specific geographic locations to capture 90% of genetic diversity present within the genetic collection area. While not yet available in the webtool, this information is available for some species in the intensives. If a genetically optimised seed sourcing strategy is available for a species of interest, a ‘related intensives’ button will be present under species information in step 3 of the webtool.
Ideally, for each species, source seed from multiple plants at each of multiple sites across a genetic collection area, either through seed collection or acquisition from seed providers. This seed can be provided to a nursery which propagates plants specifically for your project. Request that they maintain maternal lines and use even numbers from each source.
In situations where sufficient time isn’t available to propagate project-specific plants, the webtool can still guide plant selection. Check with multiple nurseries regarding the provenance of their plants and secure material from as many sites across the full span of the genetic collection area as possible. Give preference to material where maternal lines have been maintained or where seed was sourced from multiple plants. Avoid or minimise using plants grown from seed sourced from a single or few plants as all may be half siblings and encourage inbreeding in your restored population.
Maintaining maternal lines describes the practice of keeping seed or other material collected from a particular mother plant identifiable and separate from that of other mother plants through the process of collection through to propagation and planting. Maintaining maternal lines has many benefits, including being able to better quantify genetic diversity and minimise inbreeding. A pooled collection of seed from multiple mother plants may result in a nursery collection dominated by progeny from one or few mothers. Assuming that the progeny of all mother plants are equally represented may lead to an overestimation of actual genetic diversity. All the seed from one individual belong to the same maternal line and are siblings or half siblings. Being able to identify maternal line allows you interplant maternal lines to minimise inbreeding and maximise genetic diversity in progeny.
The webtool uses regional climate projections from the New South Wales and Australian Regional Climate Modelling (NARCliM2.0) project. Current climate conditions are derived from a 30-year climate average from 1985-2014. Future climate conditions are derived from a 20-year climate average, centred on 2050 (near future) and 2070 (midterm future). The two greenhouse gas emissions scenarios we use on the webtool are SSP2-4.5 (moderate) and SSP3-7.0 (severe), which are based on Shared Socio-economic Pathways (SSP) that form the foundation of Intergovernmental Panel on Climate Change (IPCC) reports. We selected mean annual temperature and mean annual precipitation as representative environmental variables (with additional variables to be added in future). We selected thresholds of 1.5°C for temperature and 300mm for precipitation following the methods of Rossetto et al. 2019, meaning that climate matched areas have a projected temperature and/or precipitation within 1.5°C and 300 mm of the target restoration site. When both variables are selected, the webtool shows the climatic envelope where the two thresholds overlap.
Glossary
Adaptive potential: The ability of a population to survive and reproduce under changing environmental conditions.
Allele: Alternate versions of DNA sequence at a given location within the genome.
Allelic diversity: The number of alleles present within a population of a species. One measure of genetic diversity.
Climate-ready: Provenances that come from areas in which current climatic conditions match those projected to occur at a target site at a future point in time under a particular model of climatic change.
Climate analogue: A location in which climatic conditions are similar to the conditions a restoration site is projected to experience in the future.
Differentiation: see Genetic differentiation.
Ecological restoration: Assisting ecosystems that have been disturbed or cleared to restore ecological function.
Gene flow: The movement of genetic material, such as differing alleles, between individuals or groups of individuals. In plants, this occurs via processes such as the dispersal of seed and pollen.
Genetic bottleneck: A sharp reduction in genetic diversity caused by a reduction in population size or by sampling of seed from too few individuals.
Genetic differentiation: Variation in hereditary information, such as allele frequencies or DNA sequences, among populations of a species.
Genetic diversity: The totality of genetic variation present in a population. A determinant of adaptive potential.
Genetic lineage: A set of individuals or populations connected by a continuous line of descent from a shared ancestor.
Genetic collection area: An area where gene flow occurs, or did occur prior to habitat fragmentation, such that mixing material from different sites aligns with natural processes. Site-specific genetic neighbourhood.
Genetic neighbourhood: An area within the distribution of a species where there are no restrictions to gene flow other than the distance between individuals, such that alleles can be shared among all individuals in the area given sufficient time.
Genetic structure: The amount and distribution of genetic variation within and between populations across the landscape.
Genetic swamping: Loss of rare alleles as a result of repeated crossing with individuals from a different genetic neighbourhood of the same species or a different species via hybridisation.
Genetically optimised seed sourcing strategy: This approach involves identifying the number of individuals and sites that seed should be collected from within specific geographic areas to capture 90% of genetic diversity present within the genetic collection area.
Heterozygosity: The average proportion of DNA sites (alleles) in the genome that are heterozygous. A measure of genetic diversity.
Heterozygous: Having two different copies of DNA at a particular location (allele) within the genome, as opposed to homozygous, where the two copies at a location are the same.
Homozygous: Having two identical copies of DNA at a particular location within the genome, as opposed to heterozygous where the two copies at a location are different. See above.
Inbreeding: The production of progeny through the mating of individuals that are closely genetically related.
Inbreeding depression: A decrease in the fitness of progeny from closely related parents due to an increase in homozygosity within the genome.
Intensive projects: The Research Centre for Ecosystem Resilience, Botanic Gardens of Sydney has collaborated with other organisations on extended initiatives that aim to obtain more detailed information beyond that provided in the webtool, including genetically optimised seed sourcing strategies.
Isolation by distance: A change in shared genetic material across geographic space due to dispersal ability limiting the mating between individuals. Populations that are further apart genetically tend to be less similar due to limited dispersal and gene flow. Importantly, this often does not lead to discrete population structure or significant local adaptations if populations are continuous across the landscape.
Maternal line: All offspring or progeny from the same mother plant.
Maintenance of maternal lines: The practice of keeping seed or other material collected from a particular mother plant identifiable and separate from that of other mother plants through the process of collection through to propagation and planting. Upon planting, maternal lines should be traceable to individuals, but material should be interplanted to minimise inbreeding and maximise genetic diversity in progeny.
Mother plant: An individual plant from which seed has been collected.
Outbreeding: The production of progeny through the mating of individuals that are not closely genetically related.
Outbreeding depression: A reduction of fitness of progeny resulting from the interbreeding of parents that are highly genetically distinct.
Population: A group of individual plants growing in the same place at the same time and interbreeding freely.
Private alleles: Alleles observed only in a single population (they are ‘private’ to that population).
Progeny: Offspring of a plant, typically seed.
Provenance: A source area for propagules (seed, cuttings etc.) used in restoration activities.
Seed production area: Areas in which native plants of known provenance are planted to harvest seed for restoration or other purposes.
Self-sustaining: The ability of a planting to survive and reproduce in the long term with minimal further active investment.
Contact Us
If you require more information about the Restore and Renew webtool, please email: [email protected].