The key research areas for Conservation Seed Science are seed phenology, quality and supply; seed dormancy; seed germination; seed banking and, seed enhancement.
Seed Phenology, Seed Quality and Seed Supply
The demand for wild-sourced seeds for conservation and restoration is increasingly rapidly. Maximising the quality and utility of seeds begins from the point of collection. Collecting seeds too early, before they reach maturity, can reduce their viability and longevity in storage, and lead to complications in determining germination and dormancy characteristics. Research in this area is focused on documenting the phenology of seed maturation and dispersal and investigating the impacts of collection timing on the quality and storage characteristics of seeds.
The development of reliable techniques for seed dormancy-break is a major area of research. Seeds of the majority of wild species are dormant at maturity, meaning that germination is not possible without first exposing seeds to specific environmental conditions. A particular focus is on understanding the role of temperature and moisture in controlling seed dormancy. Research encompasses the application of dormancy breaking techniques including dry after-ripening, stratification, and complex cycles of wetting and drying.
Germination research is also focused on unravelling the interactions between seed dormancy status and germination-promoting agents. These agents include chemicals found in smoke. Karrikins, identified as the principal germination-active compounds in smoke, have a broad-ranging action across native species as well as weeds, and this novel area of research is unravelling the mode of action of smoke and revealing new insights into the ecology of germination in fire-prone floras. Field trials are evaluating karrikinolide as a means to promote germination of the soil seedbank of both native species and agricultural weeds. Other chemicals of interest include the cyanohydrins, a second class of germination-active chemicals in smoke, and the plant growth hormone gibberellic acid.
Defining seed storage behaviour and predicting seed longevity is fundamental to ensuring that seed collections are banked under conditions that will maintain their quality. Research is focused on characterising seed storage physiology, modelling of seed longevity, and determining the effects of the storage environment on seed dormancy status. The development of cryopreservation techniques for the conservation of short-lived seeds is also a key area of research.
Enhancing the ability of seedlings to emerge and survive is necessary to improve plant establishment at restoration sites. Research is targeted at developing and adapting seed technologies such as seed priming, seed coating and pelleting, and the use of germination stimulants and anti-stress agents to increase seedling establishment. The relationship between the soil-seed interface is another important research area aimed at defining how different soil types and their different physical, hydrological, and chemical properties influence seedling emergence.