The effect of in situ seed burial on dormancy break in three woody-fruited species (Ericaceae and Proteaceae) endemic to Western Australia

2008 ◽  
Vol 56 (6) ◽  
pp. 493 ◽  
Author(s):  
Melanie A. Norman ◽  
John M. Koch
Keyword(s):  
Western Australia ◽  
Seed Viability ◽  
Early Spring ◽  
Land Restoration ◽  
Jarrah Forest ◽  
Soil Burial ◽  
True Seed ◽  
Viable Seeds ◽  
Seed Fall

The woody-fruited species Leucopogon propinquus R.Br., Styphelia tenuiflora Lindl. (Ericaceae) and Persoonia longifolia R.Br. (Proteaceae) need to be returned to restored mines in Western Australia. All species have physiological seed dormancy, however germination has been observed following the application of smoke to native habitats. We recorded seed viability, permeability to water, endocarp strength, morphology and germination ± gibberellic acid (GA3) every 3 months for 24 months of in-situ burial in the jarrah forest to determine the time of dormancy release and corresponding seed changes. The term ‘seed’ refers to the woody endocarp, plus the true seed. Persoonia longifolia reached 37% germination after burial in soil for 21 months, followed by chipping the endocarp and GA3 application. A minimum of 15 months soil burial was necessary for unchipped seeds to germinate; 22% germination was achieved after 18 months burial in soil followed by GA3 application. Viability of fresh seeds of all three species was 96–100% and remained unchanged for P. longifolia, but declined to 5 and 0% following 24 months of soil burial for L. propinquus and S. tenuiflora, respectively. Germination of the two Ericaceae species was negligible, despite the presence of viable seeds (30–63%, depending on the species) after 12 months of soil burial and substantial deterioration of the endocarp. To germinate large quantities of P. longifolia, for use in land restoration, drupes should be buried in-situ in forest soil for 18 months immediately following seed fall (early spring) and GA3 treated, following exhumation.

Distribution of Phytophthora cinnamomi in the northern jarrah (Eucalyptus marginata) forest of Western Australia in relation to dieback age and topography

2002 ◽  
Vol 50 (1) ◽  
pp. 107 ◽  
Author(s):  
K. L. McDougall ◽  
G. E. St J. Hardy ◽  
R. J. Hobbs
Keyword(s):  
Spatial Distribution ◽  
Western Australia ◽  
Aerial Photography ◽  
Phytophthora Cinnamomi ◽  
Ex Situ ◽  
Patchy Distribution ◽  
Jarrah Forest ◽  
Eucalyptus Marginata ◽  
Almost All

The spatial distribution of Phytophthora cinnamomi Rands at seven dieback sites in the jarrah (Eucalyptus marginata Donn. ex Smith) forest of Western Australia was determined by the following two baiting techniques: in situ baiting with live Banksia grandis Willd. seedlings and ex situ baiting of sampled soil and root material. Four areas within each site were sampled, reflecting dieback age and position in the landscape. Approximate dieback ages of 50, 20 and 5 years were determined by aerial photography. The 50-year-old age class was divided into wet valley floor and dry gravelly slope. Phytophthora cinnamomi was recovered most frequently from the 5-year-old (dieback fronts) and wet 50-year-old areas by both baiting techniques. It was recovered from more than twice as many areas and about five times as many samples when in situ B. grandis baits were used compared with ex situ soil and root baiting. Almost all recoveries from in situ baits were made between October and December. From both methods, it appears that P. cinnamomi has a patchy distribution within dieback sites in the northern jarrah forest. It is easily detected only on dieback fronts and wet valley floors. On dry gravelly sites affected 20 years or more ago, P. cinnamomi is rare and may even be absent at some sites. This makes confident detection of the pathogen difficult. In situ baiting at least allows a temporal component to the sampling and will be a useful method of detection in areas where P. cinnamomi is rare or transient.

Factors Limiting the Recruitment of Eucalyptus salmonophloia in Remnant Woodlands .I. Pattern of Flowering, Seed Production and Seed Fall

1994 ◽  
Vol 42 (5) ◽  
pp. 531 ◽  
Author(s):  
CJ Yates ◽  
RJ Hobbs ◽  
RW Bell
Keyword(s):  
Seed Production ◽  
Western Australia ◽  
Seed Viability ◽  
Fragmented Landscape ◽  
Viable Seed ◽  
Seed Fall ◽  
Individual Trees ◽  
Western Australian ◽  
Remnant Population ◽  
Conservation Of Biodiversity

Woodlands dominated by Eucalyptus salmonophloia F. Muell. occur throughout the fragmented landscape of the Western Australian wheatbelt. In most of these remnant woodlands, there is no regeneration of E. salmonophloia and this has become a concern for the conservation of biodiversity in the region. This study examined seed production, seed viability and pattern of seed fall in four remnant populations of E. salmonophloia in the central wheatbelt of Western Australia, to determine whether these factors are limiting recruitment. Surveys of flowering, seed production and seed fall were conducted over a two-year-period which included three potential flowering seasons. Individual trees flowered once over this period and the intensity of flowering and the proportion of flowers which set seed varied greatly between remnants. Seed from up to two consecutive flowering seasons was stored in the canopy, thus, E. salmonophloia formed substantial canopy seed stores. Seeds were released from this store throughout the year and seed fall showed only a weak winter decline. The viability of seeds released from the canopy store in each remnant population was high. These results indicate that the availability of viable seed is unlikely to be responsible for the lack of E. salmonophloia recruitment in remnant woodlands.

scholarly journals Storage in cerrado soil and germination of Psychotria vellosiana (Rubiaceae) seeds

2006 ◽  
Vol 66 (2b) ◽  
pp. 709-717 ◽  
Author(s):  
C. G. Araújo ◽  
V. J. M. Cardoso
Keyword(s):  
Seed Bank ◽  
Storage Time ◽  
Soil Seed Bank ◽  
Seed Viability ◽  
Limiting Factor ◽  
Ecological Aspects ◽  
Different Depths ◽  
Persistent Soil Seed Bank ◽  
Viable Seeds

The regeneration of plant communities from seed depends, to a large extent, on the capacity of the seed remaining viable in the soil. The viability and germination of artificially buried Psychotria vellosiana seeds in cerrado soil were studied, with the purpose of discovering some physio-ecological aspects of dispersed seeds and evaluating their potential to constitute a soil seed bank. Seed samples were placed in nylon envelopes and buried in the soil of a Cerrado reserve at two different depths and sites. Buried seeds were retrieved periodically and tested for germination along with dry-stored seeds. In general, there was a reduction in seed germination with storage time, both in soil and dry stored conditions, and in some assays exhumed seeds germinated faster than dry stored ones. In general the soil storage favoured seed viability of ungerminated seeds as compared to dry stored ones, with the seeds remaining partially viable after 10 months of storage. The lack of germination of viable seeds suggests that seeds showed true dormancy and/or required an extended time to germinate. It was observed that some seeds had germinated while buried and such in situ germination tended to increase with rainfall. The water availability in the soil might be a limiting factor for successful germination of P. vellosiana in the field, and the seeds may constitute a persistent soil seed bank in the cerrado as dispersed seeds remain viable in the soil until the following period of seed dispersal.

Emergence and survival of buried doublegee (Emex australis Steinh.) seeds

1987 ◽  
Vol 27 (1) ◽  
pp. 101 ◽  
Author(s):  
AH Cheam
Keyword(s):  
Environmental Factors ◽  
Western Australia ◽  
Inverse Relationship ◽  
Direct Relationship ◽  
Seedling Emergence ◽  
Seed Viability ◽  
Burial Depth ◽  
Emex Australis ◽  
Viable Seeds ◽  
The Waves

The emergence and survival of seed of doublegee (Emex australis Steinh.) buried at various depths were studied over 4 years at 3 climatically contrasting sites in Western Australia. We concluded that there is an optimal burial depth for seedling emergence and seed survival. Seeds placed at 1 cm gave maximum emergence but no seedling emerged from seeds placed at 15 cm or deeper. Emergence occurred mainly during the first autumn from seed less than 1 year old. Over the following 3 years, emergence declined progressively. The waves of emergence reflected the seasonal rainfall pattern, although emergence did not occur after every rainfall. There was no direct relationship between emergence and loss of seed viability. At the coolest site with higher rainfall the retention of viable seeds increased with increasing depth in the soil, whereas at warmer sites with lower rainfall there was an inverse relationship between viability and burial depth. The viable seeds exhumed after 4 years of burial were in different states of dormancy but induced or innately dormant seeds predominated at the cooler higher rainfall site. These types of dormancies and the various environmental factors will determine the number of viable seeds germinating in any given season. It is shown that even when the influx of new seed was stopped for 4 consecutive years, it was still not possible to achieve complete reduction in numbers of doublegee seeds.

scholarly journals Do applications of systemic herbicides when green fruit are present prevent seed production or viability of Alliaria petiolata (garlic mustard)?

2021 ◽  
pp. 1-17
Author(s):  
Leo Roth ◽  
José Luiz C. S. Dias ◽  
Christopher Evans ◽  
Kevin Rohling ◽  
Mark Renz
Keyword(s):  
Seed Production ◽  
Seed Viability ◽  
Early Spring ◽  
Alliaria Petiolata ◽  
Late Spring ◽  
Garlic Mustard ◽  
Viable Seed ◽  
Application Timing ◽  
Control Seed ◽  
Second Year

Garlic mustard [Alliaria petiolata (M. Bieb.) Cavara & Grande] is a biennial invasive plant commonly found in the northeastern and midwestern United States. Although it is not recommended to apply herbicides after flowering, land managers frequently desire to conduct management during this timing. We applied glyphosate and triclopyr (3% v/v and 1% v/v using 31.8% and 39.8% acid equivalent formulations, respectively) postemergence to established, second-year A. petiolata populations at three locations when petals were dehiscing, and evaluated control, seed production and seed viability. Postemergence glyphosate applications at this timing provided 100% control of A. petiolata by 4 weeks after treatment at all locations whereas triclopyr efficacy was variable, providing 38-62% control. Seed production was only reduced at one location, with similar results regardless of treatment. Percent seed viability was also reduced, and when combined with reductions in seed production, we found a 71-99% reduction in number of viable seed produced plant-1 regardless of treatment. While applications did not eliminate viable seed production, our findings indicate that glyphosate and triclopyr applied while petals were dehiscing is a viable alternative to cutting or hand-pulling at this timing as it substantially decreased viable A. petiolata seed production. Management Implications Postemergence glyphosate and triclopyr applications in the early spring to rosettes are standard treatments used to manage A. petiolata. However, weather and other priorities limit the window for management, forcing field practitioners to utilize more labor-intensive methods such as hand-pulling. It is not known how late in the development of A. petiolata these herbicides can be applied to prevent viable seed production. Since prevention of soil seedbank replenishment is a key management factor for effective long-term control of biennial invasive species, we hypothesized late spring foliar herbicide applications to second year A. petiolata plants when flower petals were dehiscing could be an effective management tool if seed production or viability is eliminated. Our study indicated that glyphosate applications at this timing provided 100% control of A. petiolata plants by 4 weeks after treatment at all locations, whereas triclopyr efficacy was inconsistent. Although both glyphosate and triclopyr decreased viable seed production to nearly zero at one of our three study locations, the same treatments produced significant amounts of viable seed at the other two locations. Our findings suggest late spring glyphosate and triclopyr applications should not be recommended over early spring applications to rosettes for A. petiolata management, as our late spring application timing did not prevent viable seed production, and may require multiple years of implementation to eradicate populations. Nonetheless, this application timing holds value in areas devoid of desirable understory vegetation compared to no management practices or mechanical management options including hand-pulling when fruit are present, as overall viable seed production was reduced to similar levels as these treatments.

Tree Species Preferences of Foraging Birds in Jarrah Forest in Western Australia.

1985 ◽  
Vol 12 (3) ◽  
pp. 461 ◽  
Author(s):  
I Abbott ◽  
PV Heurck
Keyword(s):  
Western Australia ◽  
Tree Species ◽  
Bird Species ◽  
Selective Logging ◽  
Jarrah Forest ◽  
Eucalyptus Marginata ◽  
Silvicultural Treatments ◽  
Species Preferences

A study of foraging by 10 bird species suggests that selective logging of large Eucalyptus marginata will only have affected Melithreptus lunatus, but that proposed silvicultural treatments, including removal of Banksia grandis, may affect several other bird species.

Outbreak densities of the coral predator Drupella in relation to in situ Acropora growth rates on Ningaloo Reef, Western Australia

Coral Reefs ◽  
2018 ◽  
Vol 37 (4) ◽  
pp. 985-993 ◽  
Author(s):  
C. Bessey ◽  
R. C. Babcock ◽  
D. P. Thomson ◽  
M. D. E. Haywood
Keyword(s):  
Western Australia ◽  
Growth Rates ◽  
Ningaloo Reef
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