ORCID Profile
0000-0002-9902-9940
Current Organisation
Department of Biodiversity, Conservation and Attractions
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Plant Physiology | Environmental Science and Management | Conservation and Biodiversity
Expanding Knowledge in the Biological Sciences | Flora, Fauna and Biodiversity at Regional or Larger Scales |
Publisher: CSIRO Publishing
Date: 2009
DOI: 10.1071/BT09040
Abstract: Understanding the causes of rarity and ways of managing populations of rare species is essential for their successful conservation. The present study applies the conceptual model of a hierarchy of causes to Lasiopetalum pterocarpum E.M.Benn. & K.Shep. (a critically endangered species) to understand better its reproductive and ecological attributes, possible reasons for its rarity and to determine whether this model assists in developing management strategies. L. pterocarpum subpopulations from Serpentine National Park were censused to record abundance, plant health, phenology, flower and fruit production and the presence of any seed bank. These characteristics were matched to criteria in the hierarchies of cause model. There was no evidence of recent seedling recruitment at any subpopulation. Hand-pollination produced a flower-to-fruit conversion proportion similar to that found in the field and self- and cross-pollinations produced virtually the same fruit set. Seed store in soil from beneath the native subpopulations and at a translocation site showed seed was patchily distributed and infrequent. L. pterocarpum is an obligate seeder, killed by fire and dependent on disturbance to break seed dormancy. However, smoke has no effect on germination. Seed production does not constrain population growth, because seedling regeneration after fire in 1999 was prolific at sites where plants had been growing. In the hierarchies of cause framework, the main causes of rarity for this species are taxon ecology, life-history strategy and stochasticity. Thus, concentrating active management on factors related to life history such as mosaic patch burning, fencing after fire to exclude vertebrate grazers, weed control and establishment of translocated populations will aid the preservation of this species in the wild.
Publisher: Wiley
Date: 12-09-2023
DOI: 10.1002/PPP3.10421
Publisher: CSIRO Publishing
Date: 2007
DOI: 10.1071/BT06173
Abstract: Ex situ seed conservation aims to support species survival in the wild. This can be achieved by contributing genetic material for reintroduction. The goals of reintroduction are to increase both plant and population numbers, create self-sustaining populations and ultimately remove a species from its threatened listing. Quality seed collections with a broad genetic base are required to achieve this goal. Storage conditions that minimise deterioration of seeds will maximise the quality of seeds available for future use. Additionally, ex situ seed conservation provides long-term insurance against species or genotype loss until actual or potential threats can be removed. As threats to bio ersity escalate the most judicious conservation strategies will be ones that combine available resources to provide the highest possible degree of protection. Banked seeds are available irrespective of season and periods of low fecundity. Forward planning of reintroduction projects can be achieved with knowledge of the quantity and quality of banked seed. This paper discusses the challenges facing ex situ seed conservation while highlighting the benefits of integrating ex situ seed storage and plant reintroduction to help provide for better conservation outcomes.
Publisher: CSIRO Publishing
Date: 2013
DOI: 10.1071/BT12171
Abstract: Long-term ex-situ seed storage under controlled conditions in gene banks has become an important tool for conserving threatened Australian plants however, there is scant information about the seed longevity of most species. The aim of the present study was to determine whether the seed longevity of two contrasting Australian species could be modelled using the seed viability equation, and whether the universal temperature constants are applicable to these species. Seeds of Eucalyptus erythrocorys F.Muell. (Myrtaceae) and Xanthorrhoea preissii Endl. (Xanthorrhoeaceae) were aged at moisture contents ranging from 3.9 to 15.7% and temperatures between –20 and 60°C. Survival data were fitted to the seed viability equation in one step and the species constants for each species determined. Both E. erythrocorys and X. preissii seeds exhibited orthodox seed storage behaviour whose longevity could be modelled using the seed viability equation. The viability constants were KE = 8.81, CW = 4.97, CH = 0.0412 and CQ = 0.000379 for E. erythrocorys and KE = 8.77, CW = 5.29, CH = 0.0382 and CQ = 0.000473 for X. preissii. The universal temperature constants could not be used without a significant increase in error. The storage behaviour of these two Australian species is in keeping with that of orthodox species from around the world. Predictions are that E. erythrocorys will be long-lived under gene bank conditions, whereas X. preissii would be moderately long-lived. Current long-term gene bank storage conditions appear suitable for storage of these species however, recommendations for short-term storage need to be re-evaluated.
Publisher: Cambridge University Press (CUP)
Date: 12-2004
DOI: 10.1614/WS-04-075R
Abstract: The effect of hydration (priming) treatment on dormancy release in annual ryegrass seeds from two populations was investigated. Hydration duration, number, and timing with respect to after-ripening were compared in an experiment involving 15 treatment regimens for 12 wk. Seeds were hydrated at 100% relative humidity for 0, 2, or 10 d at Weeks 1, 6, or 12 of after-ripening. Dormancy status was assessed after each hydration treatment by measuring seed germination at 12-hourly alternating 25/15 C (light/dark) periods using seeds directly from the hydration treatment and seeds subjected to 4 d postpriming desiccation. Seeds exposed to one or more hydration events during the 12 wk were less dormant than seeds that remained dry throughout after-ripening. The longer hydration of 10 d promoted greater dormancy loss than either a 2-d hydration or no hydration. For the seed lot that was most dormant at the start of the experiment, two or three rather than one hydration event or a hydration event earlier rather than later during after-ripening promoted greater dormancy release. These effects were not significant for the less-dormant seed lot. For both seed lots, the effect of a single hydration for 2 d at Week 1 or 6 of after-ripening was not manifested until the test at Week 12 of the experiment, suggesting that the hydration events alter the rate of dormancy release during subsequent after-ripening. A hydrothermal priming time model, usually used for modeling the effect of priming on germination rate of nondormant seeds, was successfully applied to dormancy release resulting from the hydration treatments.
Publisher: Department of Biodiversity, Conservation and Attractions
Date: 28-04-2020
DOI: 10.58828/NUY00952
Publisher: CSIRO Publishing
Date: 03-08-2023
DOI: 10.1071/SB23010
Abstract: The morphologically complex and charismatic genus Geleznowia (Rutaceae) is endemic to south-western Australia and faces existing and potential conservation issues associated with land clearing, climate change and commercial harvesting. Two species are currently recognised in the genus, but horticulturally recognised forms and phrase-named taxa reflect additional suspected species ersity. The genus exhibits complicated and subtle patterns of morphological variation that have historically inhibited delimitation of taxonomic entities and, as a result, precluded effective conservation assessments. Here we used ddRAD data from 25 populations across the range of Geleznowia to elucidate genomic ersity in the group in conjunction with morphological re-assessment so as to delimit species and revise the taxonomy. Our analyses consistently identified seven entities that maintain genomic distinctiveness even in sympatry with other entities, supporting the inference of reproductive barriers and lineage ergence. Morphological assessment of more than 300 specimens corroborated these seven taxa. Consequently, we recognise seven species of Geleznowia in Western Australia, retaining G. amabilis K.A.Sheph. & A.D.Crawford, recircumscribing G. verrucosa Turcz., reinstating G. calycina (J.Drumm. ex Harv.) Benth., and naming four new species as G. eximia K.A.Sheph. & A.D.Crawford, G. narcissoides K.A.Sheph. & A.D.Crawford, G. occulta K.A.Sheph. & A.D.Crawford, and G. uberiflora K.A.Sheph. & A.D.Crawford.
Publisher: CSIRO Publishing
Date: 2003
DOI: 10.1071/FP02175
Abstract: Dormancy release in seeds of Lolium rigidum Gaud. (annual ryegrass) was investigated in relation to temperature and seed water content. Freshly matured seeds were collected from cropping fields at Wongan Hills and Merredin, Western Australia. Seeds from Wongan Hills were equilibrated to water contents between 6 and 18% dry weight and after-ripened at constant temperatures between 9 and 50°C for up to 23 weeks. Wongan Hills and Merredin seeds at water contents between 7 and 17% were also after-ripened in full sun or shade conditions. Dormancy was tested at regular intervals during after-ripening by germinating seeds on agar at 12-h alternating 15°C (dark) and 25°C (light) periods.Rate of dormancy release for Wongan Hills seeds was a positive linear function of after-ripening temperature above a base temperature (Tb) of 5.4°C. A thermal after-ripening time model for dormancy loss accounting for seed moisture in the range 6–18% was developed using germination data for Wongan Hills seeds after-ripened at constant temperatures. The model accurately predicted dormancy release for Wongan Hills seeds after-ripened under naturally fluctuating temperatures. Seeds from Merredin responded similarly but had lower dormancy at collection and a faster rate of dormancy release in seeds below 9% water content.
Publisher: Oxford University Press (OUP)
Date: 30-11-2010
DOI: 10.1093/AOB/MCQ236
Publisher: CSIRO Publishing
Date: 1995
DOI: 10.1071/BT9950223
Abstract: Lomandra Labill. is a common genus in the understorey of the jarrah (Eucalyptus marginata Sm.) forest of Western Australia. Species in this genus are difficult to propagate by seed and do not readily re establish following mining. Limiting factors for germination success were explored and identified. Lomandra sonderii (F.Muell.) Ewart set very few seed (seeds per flower = 0.122). Tetrazolium tests indicated that seed viability was relatively high (50%). Germination was inhibited (0%) by the inner pericarp tissues which surround the seed and are part of the diaspore. Manual removal of the inner pericarp or leaching overcame this inhibition with a fifth of seeds subsequently germinating. Similar treatments improved germination of L. drummondii (F. Muell. ex Benth.) Ewart from 40% to 80%. Soaking L. sonderi seeds in gibberellic acid (GA3, 50 mg L-1) further improved germination (28%). Ants (C onotus sp. and Iridomyrmex sp.) collected and dispersed L. sonderi seed and are likely to improve germination in the forest by removing and consuming the inner pericarp. Only half of the Viable excised embryos of L. sonderi grew in vitro, indicating the presence of embryo dormancy. Embryo dormancy was overcome by GA3 (0.5 mM) and zeatin (0.5 mM) in the liquid culture medium. In vitro culture may be a practical means of propagating Lomandra if seed is scarce.
Publisher: CSIRO Publishing
Date: 2007
DOI: 10.1071/BT06046
Abstract: The quality of seed-conservation collections, and hence their value for species reintroduction or restoration, is critically dependent on factors operating in the period between the point of collection and arrival at environmentally controlled processing and storage facilities. The timing of the acquisition of desiccation tolerance and seed longevity in air-dry storage, in relation to mass maturity and the time of natural seed dispersal, varies across species. In some wild plant species, seed quality continues to improve up to, and possibly beyond, the point of dispersal. Holding immature berries of Solanum dulcamara L. and capsules of Digitalis purpurea L. under natural conditions enabled comparison of seed quality between seeds stored under natural conditions and those dried rapidly under seedbank dry-room conditions. While seeds from fully ripe (post-mature) capsules of D. purpurea were insensitive to different post-harvest drying treatments, seed quality declined when mature berries of S. dulcamara were held under natural conditions. These results emphasise that the selection of post-harvest treatment will not only depend on the maturity of collected seeds but also may vary across species depending on the fruit type. Except for subtropical and tropical coastal locations, ambient daytime conditions during the main seed-collecting season (November–February) across Australia can be expected to result in tolerable rates of seed deterioration for the duration of seed-collecting missions. However, because seed moisture levels can be considerably higher than when equilibrated with ambient relative humidity, post-harvest handling decisions should ideally be informed by measurements of seed moisture at the time of collection, and subsequently seed moisture should be monitored during transit.
Publisher: Wiley
Date: 05-2018
DOI: 10.1111/EMR.12315
Publisher: CSIRO Publishing
Date: 2007
DOI: 10.1071/BT06038
Abstract: The suitability of applying international standards for long-term seed storage to the Australian flora was examined by reviewing seed-storage data from the Western Australian Threatened Flora Seed Centre. The 375 collections examined represented 176 taxa from 44 genera and 16 families. A high proportion of collections, representative of some of the most common genera in Australia, maintained viability in the short ( years) and medium (5–12 years) term. Declines in germination were evident for a small number of collections, representing 10 taxa, stored for 5–12 years. However, many of the declines were collection-specific and other collections of the same taxon did not decline. Five taxa showing germination declines were represented by a single collection so it was not possible to determine whether the germination decline was directly related to the taxa, storage conditions or to other factors. Only the closely related Stylidium coroniforme and S. amabile exhibited germination declines in all collections, but cut tests of seeds remaining from germination testing indicated that viability of the collections had not declined, just the proportion to germinate for these species a change in germination conditions is a more likely explanation for the reduction in germination. The results illustrate the successful application of these seed-storage standards to threatened flora in Western Australia and highlight their suitability for the Australian flora.
Publisher: International Society for Horticultural Science (ISHS)
Date: 10-2000
Location: Australia
Start Date: 07-2021
End Date: 06-2025
Amount: $582,084.00
Funder: Australian Research Council
View Funded Activity