bluuebunny/crossref_metadata_2025 huggingface dataset:
Regeneration of Susceptible Native Species Following a Decline of Phytophthora cinnamomi over a Period of 20 Years on Defined Plots in the Grampians, Western Victoria
Authors: Weste Gretna , Kennedy Jill
Published: August 2004

Regeneration of susceptible species following a major decline in the
population and distribution of the pathogen
Phytophthora cinnamomi Rands is reported from a
reassessment of infested plots in open forest, woodland and heathland of the
Grampians. The distribution of P. cinnamomi and changes
in the vegetation were measured on quadrats set up in 1976 and 1977 and
checked biennially until 1984. In 1995, P. cinnamomi was
detected in only 15.6% of the 345 soil and root samples tested and was
present in only 28.6% of the infested quadrats compared with
100% of the samples and infested quadrats in all previous assessments.
Both the restricted distribution and the isolation of
P. cinnamomi from susceptible species without symptoms
were evidence of changes in the disease which may have been associated with
factors such as a reduced supply of susceptible host roots or an alteration in
pathogenicity or in the environment. Changes were recorded in structure and
species composition of infested plant communities compared with those that
remained pathogen-free, but few recent deaths or dieback symptoms were
observed in 1995. On the infested plots, several mature stringybark eucalypts
such as Eucalyptus baxteri and
E. obliqua had died, and the survivors had reduced crown
density and dieback of the major branches. However, regeneration in the form
of 8-year-old saplings and young seedlings showed few or no symptoms despite
the isolation of P. cinnamomi from the roots. The
understorey of infested plots comprised a dense growth of field-resistant
plants such as Leptospermum spp. and sedges entwined
with dodder laurel, whereas the uninfested plots contained a species-rich
heath flora of which 54% were known to be susceptible to
P. cinnamomi. Regeneration and continuing survival of 24
susceptible species from 11 different families were recorded as small plants
on various infested quadrats. However, 12 susceptible species from 7 different
families had failed to regenerate. Pathogen populations may increase with the
renewed supply of susceptible roots, but independent of pathogen potential,
the emerging susceptible species may not be able to compete effectively
against the dense field-resistant understorey in infested plots in order to
re-establish the original diverse heathland understorey.
Cluster Roots and Mycorrhizae in Casuarina cunninghamiana: their Occurrence and Formation in Relation to Phosphorus Supply
Authors: Reddell Paul , Yun Yang , Shipton Warren A.
Published: August 2004

The occurrence of mycorrhizae and cluster roots was assessed in natural
populations of Casuarina cunninghamiana Miq. in north
Queensland. Cluster roots were found at 90% of the sites surveyed. By
contrast, arbuscular mycorrhizae occurred at only 45% of sites and the
extent of colonisation was low. No ectomycorrhizae were found during this
survey. Formation of arbuscular mycorrhizae and cluster roots in
C. cunninghamiana seedlings in relation to external P
supply was investigated in glasshouse experiments. Inoculation with the
arbuscular mycorrhizal fungus, Glomus, significantly
increased seedling dry weight at low P supply (10 mg P per kg soil), but had
no effect in the absence of P or at P supply rates greater than 10 mg P per kg
soil. Mycorrhizal colonisation of roots was highest at 0 and 10 mg P per kg
soil and declined with further increases in P supply. No mycorrhizae formed at
or above 100 mg P per kg soil. The number, dry weight and proportion of root
biomass allocated to cluster roots in solution culture decreased with
increasing P supply, and followed a generally similar pattern to that observed
for arbuscular mycorrhizae in sand culture. No cluster roots formed at P
supply of 100 µM P or higher, and the form of nitrogen available to the
plant (either adequate supply of mineral nitrogen or dependency on symbiotic
N2 fixation) had no effect on cluster root formation at
any level of P supply. Casuarina cunninghamiana occurs
naturally along stream and river banks and cluster roots may be advantageous
at these sites by providing a reliable mechanism to enhance nutrient uptake in
seasonally inundated environments that are unlikely to be favourable to
mycorrhizal formation and activity.
A Vegetation History and Quantitative Estimate of Holocene Climate from Chapple Vale, in the Otway Region of Victoria, Australia
Authors: McKenzie G. Merna , Kershaw A. Peter
Published: August 2004

A well-dated pollen record from Chapple Vale in the north of the Otway region
provides a detailed history of vegetation and environments through the last c.
7000 years. From the commencement of the record, a stand of cool temperate
rainforest, dominated by Nothofagus cunninghamii (Hook.)
Oerst., grew on or around the site and was surrounded by eucalypt-dominated
tall open forest. Between c. 5200 and 4600 years BP (before present), the
rainforest declined and tall open forest predominated. Some time after 4400
years BP there was a major and consistent increase in charcoal values,
suggesting an increase in burning, the progressive development of
scrub–heath vegetation on site and the replacement of tall open forest
vegetation by eucalypt woodland surrounding the site. The fossil evidence for
N. cunninghamii on the site and its present restriction
to wetter areas and gullies of the Otway Ranges indicate, from the application
of the present bioclimatic range of the species, a mean annual temperature and
winter temperatures that were c. 1˚C cooler than present, and summer
temperatures that were possibly slightly cooler than present, together with a
much higher effective precipitation from the commencement of the record until
c. 4600 years BP. These climatic estimates are in accord with those derived
from a similar study of changing distributions of
N. cunninghamii in the Central Highlands of lower mean
annual and cooler summer temperatures and higher effective precipitation over
this time span. However, for winter, the evidence is equivocal. While the
Otway estimates suggest lower temperatures, the Central Highlands findings
show slightly higher temperatures. Taking into account additional present-day
records for N. cunninghamii, it is likely that the Otway
estimates are the most reliable.
Imbricacy and Stomatal Wax Plugs Reduce Maximum Leaf Conductance in Southern Hemisphere Conifers
Authors: Brodribb Tim , Hill Robert S.
Published: August 2004

An examination of the relationship between theoretical maximum leaf
conductance as calculated from stomatal dimensions, and measured maximum leaf
conductance was undertaken in a group of Southern Hemisphere conifers. The
relative effects of stomatal wax plugs, found in most species of conifers in
the Southern Hemisphere, and imbricate leaf arrangement were expressed as a
percentage inhibition of maximum leaf conductance
(gmax) calculated from the ratio
of measured gmax to theoretical
gmax Because of the similar
stomatal dimensions of all species, measured
gmax was proportional to stomatal
density in plugged and unplugged species, with species without wax plugs
producing maximum leaf conductances on average 91% of calculated
gmax, while in species with
plugged stomata measured gmax was
on average only 35% of theoretical
gmax. There was no effect produced
by imbricacy in itself, but when combined with epistomy,
gmax was significantly reduced to
about 17% of theoretical
gmax. This is clearly illustrated
by comparisons of juvenile-adult foliage, and closely related imbricate and
non-imbricate species. The adaptational advantages of imbricacy and wax plugs,
and the potential for inferring
gmax of fossil taxa are discussed.
The Functional Significance of Leaf Angle in Eucalyptus
Authors: King David A.
Published: August 2004

The genus Eucalyptus L’Herit. contains a large
proportion of species with nearly vertical foliage, as well as species with
shallower leaf angles. This review uses the observation that species with
steeply inclined foliage have concolorous leaves (same colour on both sides)
to assess the broad patterns of leaf angle across the natural range of
Eucalyptus. Species with shallow-angled leaves are shown
to be largely restricted to areas of moderate to high rainfall and mild to
warm climates along the margins of Australia where they co-occur with
steeper-leaved species. A review of patterns in leaf angle on other continents
and the functional significance of this trait supports the commonly held view
that vertical leaves have been selected to reduce midday heat loads, thereby
increasing water use efficiency and hence carbon gain, in eucalypts of dry
interior regions. However, steep-leaved species also dominate the wetter, more
productive montane forests of south-eastern Australia and Tasmania. In this
case, vertical foliage may increase the competitive ability of individuals
through a number of mechanisms, including the more efficient interception of
light for the low sun angles prevalent at high latitudes, and by somewhat
ameliorating low leaf temperatures during still, clear nights, thus decreasing
subsequent cold-associated photoinhibition.
The Relationship between Attributes of Plants Represented in the Germinable Seed Bank and Stocking Pressure in a Semi-arid Subtropical Rangeland
Authors: Navie S. C. , Rogers R. W. , Rogers R. W.
Published: August 2004

A range of diaspore and mature plant attributes of the species represented in
the germinable seed bank of a semi-arid subtropical Queensland sheep rangeland
was investigated. The attributes of both the diaspores themselves and the
plants that produced them changed as distance from water increased. Close to
the water source, species with prostrate or erect growth habit and with low
palatability and capsular fruits were common, whereas further from the water
source plants with ascending growth habits, high palatability and mericarpic
fruits were more frequent. At close proximity to water, species with diaspores
that germinated rapidly, were unornamented, with unassisted dispersal and
rounded in shape were common, whereas at greater distance from water, species
tended to possess diaspores which germinated slowly, were ornamented
(possessed awns, barbs, or hairs), with an elongated shape. Longevity of the
plants (annual or perennial) was not significantly affected by distance from
water. The dormant, vegetative and reproductive phases of plants that are
successfully incorporated into the germinable soil seed bank can, therefore,
be related to success under the different stocking intensities present at
different distances from water.
Genetic Differentiation in Natural Populations of Grevillea robusta
Authors: Harwood C. E. , Moran G. F. , Bell J. C.
Published: August 2004

Genetic variation in 23 natural populations of
Grevillea robusta A.Cunn. from across the natural range
of the species was examined using 20 isozyme loci assayed in young seedlings.
Mean expected heterozygosity per population,
He , varied from 0.080 to 0.131
with an average of 0.105. The genetic diversity of individual populations did
not appear to be related to their ecological characteristics (araucarian vine
forest or riverine habitat types) or their geographic locations. A genetic
distance analysis indicated a significant separation of the populations into
two regional groups, eight from the northern part of the natural range and the
remaining 15 from central and southern areas. Between-population differences
accounted for 17.9% of the total genetic variation, one-third of which
was attributable to the difference between the two regional groups. Most
alleles at the 20 loci occurred across most or all of the geographic range.
This, and the low level of genetic differentiation between populations,
suggest that genetic exchange between populations has been maintained, despite
the pattern of natural distribution of the species in small, separated
populations.
Seed Ecology of Hypericum gramineum, an Australian Forb
Authors: Willis Anthony J. , Groves Richard H. , Ash Julian E.
Published: August 2004

Aspects of the seed ecology of Hypericum gramineum
Forster, a perennial forb that is native to Australia, were examined in
several germination and seed predation experiments. Fresh seeds were innately
dormant. Highest germination of non-dormant seeds occurred in the light at a
temperature regime of approximately 35/25˚C. The results of field
experiments indicated that there was no strongly seasonal effect on
germination. Predators, such as ants, removed < 20% seeds, thereby
suggesting that post-dispersal seed predation is relatively unimportant in the
dynamics of H. gramineum populations. Seeds that escape
predation and that fail to germinate after dispersal may be incorporated into
a persistent soil seed bank.
The Impact of Phytophthora cinnamomi on Six Rare Native Tree and Shrub Species in the Brisbane Ranges, Victoria
Authors: Peters Des , Weste Gretna
Published: August 2004

The impact of Phytophthora cinnamomi was measured on six
native tree and shrub species occurring in the Brisbane Ranges, Victoria, that
are considered significant, rare or vulnerable and likely to become
endangered. Seedlings of Eucalyptus yarraensis (rare)
and cuttings of Grevillea chrysophaea (significant),
Olearia pannosa,
Pultenaea graveolens (both vulnerable) and
Prostanthera decussata and
Rhagodia parabolica (both rare) were grown in
disease-free soil and inoculated with P. cinnamomi.
After 60 days, all plants of G. chrysophaea and
P. graveolens were dead and, hence, were regarded as
highly susceptible. Inoculated plants of P. decussata
developed severe symptoms and 13% died, while
O. pannosa showed decreased vigour with 11%
dying. Both species were classified as susceptible. Some plants of
R. parabolica developed symptoms and were slightly
susceptible, butE. yarraensis was resistant. A foliage
spray of the phosphonate, Foli-R-Fos (dipotassium phosphonate) on healthy
susceptible species, followed by stem inoculation with the pathogen, reduced
both stem infection and mortalities, but did not eliminate the pathogen. The
concentration of 3% was slightly phytotoxic to
G. chrysophaea and P. decussata.
The distribution of the six species and of disease due to
P. cinnamomi was mapped. Stands of
G. chrysophaea, O. pannosa and
P. graveolens are diseased and at risk. One of the few
known stands of P. decussata was invaded recently. When
measured on replicate quadrats located in areas of recent disease, old disease
and areas free from disease, P. cinnamomi was shown to
produce significant reductions in plant density, plant growth, flowering and
regeneration, particularly in areas recently invaded by the pathogen, but less
on old infested areas. One-third of the population of
O. pannosa is dying due to
P. cinnamomi and its seed production is inhibited. There
is a strong decline in populations of G. chrysophaea,
and P. graveolens, which may place these species at
risk.
Temperate Eucalypt Woodlands: a Review of Their Status, Processes Threatening Their Persistence and Techniques for Restoration
Authors: Yates Colin J. , Hobbs Richard J.
Published: August 2004

Temperate eucalypt woodlands were once widespread throughout southern
Australia and Tasmania. Following European settlement, woodlands were cleared
for agriculture, or grazed and converted to pasture. In the wheatbelts of
south-western and south-eastern Australia, woodlands have been almost
completely eliminated from the landscape with as little as 3% of some
woodland types remaining. As a consequence, some temperate eucalypt woodland
communities are amongst the most poorly conserved ecosystems in Australia. The
main effect of widespread clearing and grazing has been the loss of habitat.
This has had a devastating impact on the woodland flora and fauna. A number of
species have become extinct and many are threatened; many others have
undergone regional and local population declines. Woodlands now occur
throughout much of their former range as remnants of varying size, quality and
isolation. Many of these are under threat from further clearing, rising saline
water tables and increased inundation, livestock grazing, nutrient enrichment,
soil structural decline, altered fire regimes and the invasion of exotic
weeds. The degradation and loss of biodiversity in temperate eucalypt
woodlands will continue unless clearing stops and the management of remnants
changes; this will invariably involve ecological restoration both at the patch
and landscape level. The review discusses approaches to restoration and
reveals that there are few data in the published literature describing
techniques for reversing degrading processes and restoring diversity structure
and function in remnant woodlands. This information is urgently needed. Past
research on temperate eucalypt woodlands has focused on identifying the
processes of degradation and these are now relatively well documented. There
is a need to shift the focus of research to developing solutions for these
problems.
Seed Ageing and Smoke: Partner Cuesin the Amelioration of Seed Dormancyin Selected Australian Native Species
Authors: Roche Shauna , Dixon Kingsley W. , Pate John S.
Published: August 2004

Seed germination of many Australian native plant species has consistently
proven to be fractious. With the discovery of smoke-mediated germination, it is
now possible to better understand the heterogeneity in germination patterns for
a wide range of species both in situ and
ex situ. In the present study, over 180 species were
examined as to viability and smoke responsiveness of freshly collected seed.
Soil storage and a number of commonly used seed pre-treatments were employed in
combination with smoke to examine both longevity in artificially constructed
seed banks, and the role of seed ageing in improved germination. Methods of
smoke application for commercial use were also investigated. Viability
decline over 1 year varied between 10% and 80%. Reductions of as
little as 15% were found to compromise the ability of a number of
species to successfully recruit in consecutive seasons. When fresh seed was
used,almost 70% of species tested responded positively to smoke whether
applied prior to or after sowing. Variation in success between the two methods
confirmed earlier conclusions that substances contained in plant-derived smoke
may be inhibitory at high concentrations for particularly sensitive species.
Only 10% of species under investigation recorded optimum germination
with seed ageing alone but when smoke was applied as a treatment after soil
storage, 60% of species responded positively. Implications for
horticulture, rehabilitation, seed bank research and habitat management are
discussed.
A Conceptual Model for Integrative Studies of Epiphytes: Nitrogen Utilisation, a Case Study
Authors: Bergstrom D. M. , Tweedie C. E.
Published: August 2004

A conceptual, hierarchical model for the study of epiphytes in complex
rainforest ecosystems is illustrated. The model incorporates an integrative,
multidisciplinary approach with ecological parameters compartmentalised into
relevant spatial, temporal and organisational scales. The model can be applied
to other spatially complex ecosystems such as coral reefs. An example showing
the use of the model is presented. The natural abundance of
15N in three species of epiphyte growing on one tree is
examined. In this pilot study, interpretation of a complex data set has been
aided by the use of a hierarchical approach. A high degree of spatial
heterogeneity in the nitrogen pool within the tree was found, with epiphytes
accessing at least three sources of nitrogen: an atmospheric source, a
nitrogen fixed source and the phorophyte itself through decomposed litter.
Observations of the Photosynthetic Physiology of Tree Species within the C3 Monocotyledon Genus Pandanus, and Comparison with Dicotyledon C3 Tree Species
Authors: Lovelock Catherine E.
Published: August 2004

Photosynthetic characteristics of tree species from the tropical
C3 monocotyledon genus Pandanus
were compared with C3 dicotyledon species growing in
similar environments. The Pandanus species had similar
maximum photosynthetic rates
(Amax) to dicotyledon tree species
in leaves from both sun and shaded environments when
Amax was expressed on an area
basis. Because of the low specific leaf area of the schlerophyllous leaves of
the Pandanus compared to the dicotyledon species, the
similarity in Amax was no longer
evident when Amax was expressed on
a dry-weight basis. Leaf dark respiration rates of the
Pandanus on a leaf area and weight basis were generally
lower than the shade-intolerant dicotyledons and similar to the shade-tolerant
dicotyledon species. Low dark respiration rates and low specific leaf area of
the Pandanus may be important characteristics for growth
and survival in environments where resource levels are low and the likelihood
of tissue damage is high.
Quaternary Palynological Records from Perched Lake Sediments, Fraser Island, Queensland, Australia: Rainforest, Forest History and Climatic Control
Authors: Longmore Maureen E.
Published: August 2004

Pollen, carbonised particle and chemical analysis of a 6 m core from the Old
Lake Coomboo Depression, a perched lake basin situated in one of the oldest
dune systems on Fraser Island, demonstrates vegetation and hydrological change
through a series of glacial cycles. The pollen assemblage shifts from
predominantly rainforest with Araucaria sp. (Juss.)
surrounding a deep water lake at c. 600 ka, to a dryer rainforest with
Podocarpus sp. (L’Herit) and an intermediate lake
after c. 350 ka, to a more sclerophyllous forest until before the Last Glacial
Maximum (LGM). During the Last Interglacial (c. 120 ka) and before (c. 22 ka)
the LGM, Araucaria sp. pollen frequencies increase
before falling dramatically, open forest appears to shift to the robust
association of myrtaceous shrubs characteristic of the older dune systems to
the west of the island, and lake levels fall probably below the lake floor.
After the LGM, open forest returns, but Araucaria sp.
pollen frequencies never recover and the lake becomes an ephemeral system with
a fluctuating water-table in the Holocene. The record is interpreted as
reflecting retrogressive vegetation succession driven primarily by an overall
decrease in effective precipitation over, at least, the last 350 ka. The
inferred long-term changes in climate have major implications for the survival
of relict rainforest.
Influence of Leaf Type and Plant Age on Leaf Structure and Sclerophylly in Hakea (Proteaceae)
Authors: Groom Philip K. , Lamont Byron B. , Markey Adrienne S.
Published: August 2004

Hakea Schrader (Proteaceae) species possess one of two
contrasting leaf morphologies—broad or terete. Terete leaves are either
simple (needle-like) or two- or three-pronged, and are further characterised
by their greater thickness (> 1 mm), smaller projected area and mass,
higher mass per unit area (a measure of sclerophylly) and lower density than
broad leaves. Broad leaves are much more variable in their morphology, ranging
from narrow-linear to fan-shaped or ovoid-elliptic, and may be flat, undulate,
shell-shaped or spiralled. The greater thickness and sclerophylly of terete
leaves can be partially attributed to the presence of a prominent,
thick-walled parenchyma core and increased palisade thickness. The core
contains a compact conduit of fibre-capped vascular bundles. The
sclerophyllous nature of broad leaves is due to their high density,
attributable to their thin palisade and large fibre caps surrounding the main
vascular bundles. Both leaf types have a thick cuticle (> 20 µm) in
mature plants, and sunken stomates, with terete leaves possessing a greater
stomatal density than broad leaves. Both leaf types are isolateral and hence
amphistomatous. Within a species, adult and seedling leaves having a similar
leaf type differ morphologically rather than anatomically, with an overall
increase in leaf thickness and higher levels of sclerophylly in adult leaves.
Some species produce broad seedling leaves that are eventually replaced by
terete adult leaves.
Dual Control of Flower Initiation and Development by Temperature and Photoperiod in Hardenbergia violacea
Authors: King R. W.
Published: August 2004

Exposure to both short-day photoperiods (< 12.5 h daily) and cool
temperatures (15–18°C) is optimal for inflorescence initiation and
development in the woody perennial Hardenbergia violacea
(Scheeve) Stearn, an Australian leguminous plant species. After 9–12
weeks exposure to inductive conditions the inflorescences were 1–2 cm
long and floral organ primordia were evident. At this stage of development,
transferring plants to warmer conditions (e.g. 22°C) and/or long days
led to flower bud abortion, abscission of the inflorescence and a resumption
of vegetative growth within 30 days. Conversely, flowers opened with continued
exposure to short days. Flower initiation and development of this
Hardenbergia selection (cultivar Mini haha) is thus
restricted to a narrow temperature range (15–18°C) in combination
with a requirement for exposure to short days. Such complexity must be
important in adaptation of Hardenbergia to its
environment.
Tolerance of Thermal Shock in Seeds
Authors: Bell David T. , Williams Deanne S.
Published: August 2004

Tolerance to high temperatures is an important attribute of seeds of species
that inhabit regions that periodically burn. In some species, seeds not only
survive fire, but require a heat shock in order to germinate. Twenty-one taxa,
representing a range of ecological attributes, were tested for germination
following scarification and boiling-water treatments of up to 90 min duration.
The black-coloured seeds from the serotinous fruits of
Dryandra sessilis (Knight) Domin.,
Hakea lissocarpha R.Br. and four species of
Eucalyptus were vulnerable to temperatures of 100˚C
with increasing duration of exposure associated with reduced germination
percentage. Seeds of Xanthorrhoea preissii Endl., a
species that flowers in response to fire and disperses seed into a post-fire
environment unlikely to experience a second fire, also had few seeds that
could tolerate even 30 s of boiling-water treatment. The reddish coloured,
soil-borne, leguminous species seeds showed enhanced germination after short
durations of 100˚C, but gradually decreasing proportions of seeds
germinated as heat-shock durations were lengthened to 90 min. Within the genus
Eucalyptus, seeds of relatively large mass and thick
seed coats survived longer than seeds of small mass and thin seed coats. In
contrast, within the legumes, seed mass, wall thickness and cellular structure
were not strong indicators of thermal-shock tolerance. Differences in
germination percentage between scarified and short-term heat-shock treatments
indicated that the heat required to break dormancy in Australian legumes may
not always be related to breaking an impervious seed coat. Australian native
legumes appear more tolerant to thermal-shock than species reported from other
regions of the world.
Genetic Control of Reproductive and Vegetative Phase Change in the Eucalyptus risdonii - E. tenuiramis Complex
Authors: Wiltshire R. J. E. , Reid J. B. , Potts B. M.
Published: August 2004

Eucalyptus risdonii Hook.f. is believed to be a
juvenilised form of its sister species, E. tenuiramis
Miq., differing largely in the retention of the juvenile leaf type at
reproductive maturity. The genetic basis of this ontogenetic variation was
examined by monitoring reproductive and vegetative phase changes in 1201
open-pollinated progeny from 40
E. risdonii–E. tenuiramis
populations in a field trial over 6 years. Vegetative and reproductive phase
changes were highly heritable and genetically independent within populations.
Estimates of individual narrow-sense heritabilities for height and timing of
vegetative phase change ranged from 0.46–0.67 and 0.19–0.23
respectively, and for time of first flowering from 0.31–0.41. Variation
in the height of vegetative phase change amongst progeny grown in a common
environment was very similar to that observed in the natural populations from
different environments, demonstrating a genetic basis to a stepped cline in
the retention of the juvenile leaf form (neoteny). However, a separate pattern
of variability in the time to flowering was evident, with precocious flowering
found in a number of phenetic groups. This independent variation of
reproductive and vegetative phase changes may allow dramatic heterochronic
alterations in morphology and physiology with minimal genetic change. The
continuous nature of the neotenic variation suggests that speciation by this
mode of evolution is not yet complete in the
E. risdonii–E. tenuiramis
complex, but has presumably operated to produce many other neotenous eucalypt
species.
Allocasuarina (Casuarinaceae) Invasion of an Unburnt Coastal Woodland at Ocean Grove, Victoria: Structural Changes 1971 - 1996
Authors: Lunt Ian. D.
Published: August 2004

Changes in vegetation structure in a long-unburnt (> 115 years) woodland at
Ocean Grove, Victoria, were assessed by comparing density data collected in
1971 by Withers and Ashton (1977) with comparable data from 1996. The changes
in structure outlined by Withers and Ashton (1977) continued to operate over
the 25 year period, namely, a dramatic increase in the density of
Allocasuarina littoralis (Salisb.) L.A.S.Johnson, and a
continued decline in the once-dominant eucalypts, especially
Eucalyptus ovata Labill. The density of
A. littoralis increased from 911 trees
ha–1 in 1971 to 3565 trees
ha–1 in 1996. Most of the surviving
E. ovata displayed extensive crown dieback, and appear
likely to die in the near future. Many eucalypt seedlings which were planted
into burnt and unburnt experimental plots in 1971 were still alive in 1996,
but most were less than 0.5 m tall and suppressed by tall regrowth of
A. littoralis and Acacia pycnantha
Benth. In the continued absence of fire and other disturbances, it is
predicted that A. littoralis will continue to dominate
the reserve, leading to further declines in eucalypts. It appears unlikely
that a single fire will prevent A. littoralis dominance,
and frequent burning at short intervals may be required to reinstate an open
woodland structure.
Breeding and Mating Systems of Australian Proteaceae
Authors: Goldingay Ross L. , Carthew Susan M.
Published: August 2004

There has been a significant increase in the number of studies investigating
plant breeding and mating systems over the past 10 years. The family
Proteaceae, in particular, has dominated such research conducted in Australia.
Thus it is now timely to present a critical review of the breeding and mating
systems of the Australian Proteaceae. It is hoped that this will stimulate
further research. The review covers key events between pollen deposition on
stigmas through to fruit set. The genus Banksia,
although not the most diverse of the family, has received a disproportionate
amount of attention. It has featured in nine published studies of
self-compatibility compared to 13 studies spanning the other 45 genera and has
featured in eight genetic studies of the mating system compared to just two on
other genera. Few studies have assessed the timing of stigma receptivity
despite the intriguing situation in most Proteaceae of auto-deposition of
self-pollen on or near stigmas at anthesis. Studies suggest that stigmas are
not receptive until 0.5–4 days after anthesis.
Banksia species appear to show low levels of
self-compatibility although one subspecies shows high levels of selfing and
evidence of selective fruit development. Self-compatibility may be more common
in other genera, although a dearth of studies precludes generalisation.
Assessment of mating systems indicates almost complete outcrossing for most
species, lending support to the idea of selective fruit development. It is
clear that many further studies of all topics are required but particularly
across a wide range of genera because many have not been studied at all.
An Evaluation of the AFLP Fingerprinting Technique for the Analysis of Paternity in Natural Populations of Persoonia mollis (Proteaceae)
Authors: Krauss Siegfried L. , Peakall Rod
Published: August 2004

The accurate assignment of paternity in natural plant populations is required
to address important issues in evolutionary biology, such as the factors that
affect reproductive success. Newly developed molecular fingerprinting
techniques offer the potential to address these aims. Here, we evaluate the
utility of a new PCR-based multi-locus fingerprinting technique called
Amplified Fragment Length Polymorphism (AFLP) for paternity studies in
Persoonia mollis (Proteaceae). AFLPs were initially
scored for five individuals from three taxonomic levels for 64 primer pairs:
between species (P. mollis and
P. levis), between subspecies
(P. mollis subsp. nectens and
subsp. livens), between individuals within a single
population of P. mollis, as well as for a naturally
pollinated seed from a single P. mollis subsp.
nectens plant. Overall, 1164 fragments (24.6% of
all fragments) were polymorphic between species, 743 (16.5%) between
subspecies, 371 (8.6%) between individuals within a single population,
and 265 (6.2%) between a plant and its seed. Within a single
P. mollis population of 14 plants, 42 polymorphic
fragments were scored from profiles generated by a single AFLP primer pair.
The mean frequency of the recessive allele (q) over these 42 loci was 0.773.
Based on these observations, it will be feasible to generate well over 100
polymorphic AFLP loci with as few as three AFLP primer pairs. This level of
polymorphism is sufficient to assign paternity unambiguously to more than
99% of all seed in experiments involving small, known paternity pools.
More generally, the AFLP procedure is well suited to molecular ecological
studies, because it produces more polymorphism than allozymes or RAPDs but,
unlike conventionally developed microsatellite loci, it requires no prior
sequence knowledge and minimal development time.
Consistent Individuality in the Timing and Magnitude of Flowering by Adenanthos obovatus (Proteaceae)
Authors: Wooller R. D. , Wooller S. J.
Published: August 2004

The patterns of flowering of 58 individually marked
Adenanthos obovatus Labill. plants were recorded from
1983 to 1990 near Perth, Western Australia. Individuals started to flower
asynchronously but most then continued to flower until the end of the
nine-month flowering season each year. Individuals were highly consistent
between years both in the numbers of flowers they produced and in their onset
and peak of flowering relative to other members of the population. This
consistency was retained after rapid regeneration by 24 plants cut back to
ground level during one summer. The number of flowers borne by an individual
was not related to its above-ground biomass but to its duration of flowering,
and plants bearing more flowers set more seed. These traits may be related to
the pollination of this modally outcrossing species by a resident small
nectarivorous bird.
Fine-scale Genetic Structure of Eucalyptus globulus ssp. globulus Forest Revealed by RAPDs
Authors: Skabo S. , Vaillancourt R. E. , Potts B. M.
Published: August 2004

Fine-scale genetic structure in Eucalyptus globulus ssp.
globulus native forest was detected using 69 randomly
amplified polymorphic DNA (RAPD) markers. The association between genetic
similarity and geographic distance was studied among 51 trees from the
Tinderbox locality in Tasmania (distance ranging from 2 m to 4 km apart) and
compared to 18 trees from localities up to 100 km away. Twenty pedigreed
F1s were used as controls to scale the RAPD similarity
among individuals to pedigree similarity. The association between genetic
similarity and geographic distance was weak, yet at Tinderbox, highly related
trees were shown to occur within 25 m of one another. There is an abrupt drop
in average similarity after about 25 m, with no significant change with
distances up to 14 km. Nevertheless, Tinderbox trees outside the 25 m genetic
patches are still more similar to each other than they are to trees from the
Mayfield Bay locality 100 km away. These results suggest that
E. globulus native forests have a family group
structure, superimposed on a noisy, background level of lower relatedness
which extends over a wider geographical range. This study is unique in
demonstrating the congruence between fine-scale genetic structure as revealed
by molecular data and previous quantitative genetic data.
Use of Gas Chromatograms of the Essential Leaf Oils of the Genus Eucalyptus for Taxonomic Purposes. Part II. Species of Eucalyptus series Levispermae, Curviptera subseries Orbifoliae, Caesiae, Ovulares and
Authors: Dunlop Peter J. , Bignell Caroline M. , Hibbert D. Brynn , Brooker M. I. H.
Published: August 2004

Principal components analyses were performed on the gas chromatograms of the
essential oils of many of the taxa in the botanical classifications (a)
E. series Levispermae, (b)
E. series Curviptera subseries
Orbifoliae, (c) E. series
Caesiae, (d) E. series
Ovulares and (e) E. subgenus
Eucalyptus; single trees were used for each taxa. The
scores of the principal components of the component oils in each
classification were examined to see if any correlation was revealed between
the botanical classification based on morphology and the biochemical
classification of components of the leaf oils.
Initiation Processes in Copolymerization Studied by the Nitroxide Radical-Trapping Technique: Ethyl Vinyl Ether and Acrylonitrile
Authors: Busfield W. Ken , Busfield W. Ken , Jenkins Ian D. , Jenkins Ian D. , Monteiro Michael J. , Monteiro Michael J.
Published: August 2004

The nitroxide free-radical trapping technique has been applied to an
investigation of the initiation mechanism of the copolymerization of ethyl
vinyl ether and acrylonitrile initiated by t-butoxyl radicals. In addition to
a range of products normally produced from reactions with individual monomers,
four new trapped products each involving both monomers have been observed.
These arise because the strongly electron-accepting acrylonitrile reacts so
fast with the strongly nucleophilic ethyl vinyl ether radical end groups that
the reaction competes successfully with radical trapping. t-Butoxyl radicals
react 3-6 times faster with ethyl vinyl ether than with acrylonitrile
depending on solvent, illustrating the strong electrophilic nature of the
t-butoxyl radicals. Reactions carried out in non-olefinic solvents show that
polarity is not a major factor in the solvent e®ect. It is more likely to
be due to selective interaction of one monomer with the radical end enhancing
its electrophilic nature. A similar e®ect is caused by a hydrogen-bonding
solvent.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXVI Synthesis, Spectroscopy and Structural Systematics of Some 1 : 3 Adducts of Copper(I) Compounds with Triphenylstibine, [(Ph3Sb)3CuX], X = Br, I, ONO2
Authors: Hart Robert D. , Bowmaker Graham A. , White Allan H.
Published: August 2004

The syntheses of adducts,
[(Ph3Sb)3CuX], X
= Br, I, NO3, obtained by crystallization of 1 :
3 CuX/SbPh3 mixtures from appropriate solvents are
described, together with their room-temperature single-crystal X-ray structure
determinations. The bromide, obtained as a chloroform monosolvate from that
solvent, is triclinic, P-1,
a 13·861(4), b
14·306(4), c 14·347(4) Å, α
84·40(2), β 86·93(2), γ 75·56(2)°,
Z = 2 f.u., conventional R
on F being 0·053 for
No = 4136 independent
‘observed’ (I >
3σ(I)) reflections; this solvate is isomorphous
with its previously recorded chloride counterpart. The iodide is triclinic,
P-1, a
14·55(1), b 14·385(2),
c 23·626(6) Å, α 91·78(1),
β 90·77(4), γ 92·54(5)°;
Z= 4, R 0·050 for
No 6917, and isomorphous with its
phosphorus counterpart. The nitrate, although a methanol sesquisolvate, is
also isomorphous with the chloride and bromide, a
13·369(9), b 14·398(3),
c 14· 504(12) Å, α 82·29(5),
β 84·39(6), γ 75·11(4)°, R
0·052 for No 5672. Cu-X are
(2·235(5) (Cl)), 2·366(3) (Br), 2· 556(2) ( 2 ) (I),
1·98(1) Å (ONO2), appreciably shorter than
in their previously recorded EPh3, E = P, As
counterparts. The far-infrared spectra of
[(Ph3Sb)3CuX] showed no
clear v(CuX) bands, in contrast to the situation
reported previously for the corresponding Ph3P and
Ph3As compounds. It is likely that
v(CuCl) is masked by a strong band at 270
cm-1 due to the Ph3Sb ligand.
However, the region below 250 cm-1 in which the
v(CuX) bands are expected for the X = Br, I
complexes contains no strong ligand bands. Possible reasons for the absence of
v(CuX) bands in these complexes are considered.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXVIII Synthesis and Structural Systematics of Some 1 : 3 Adducts of Silver(I) Compounds with Triphenylstibine, [(Ph3Sb)3AgX], X = Cl, I, SCN, NCS, CN, ONO2
Authors: Effendy  , Kildea John D. , White Allan H.
Published: August 2004

The syntheses and room-temperature single-crystal X-ray structural
characterization of 1 : 3 adducts formed between silver(I) (pseudo-) halides,
AgX, and triphenylstibine, SbPh3, are described for X
= Cl, I, SCN, NCS, CN, NO3 (1)-(6). The chloride,
as its methanol solvate (1a), is isomorphous with the arsine analogue:
triclinic, P-1,
a 13·373(4), b
14·48(6), c 14·702(3) Å, α
83·49(3), β 87·76(2), γ 76·45(3)°;
Z = 2, conventional R on
F being 0·046 for No 5514
independent ‘observed’ reflections (I > 3σ(I )). A new
form (1b) of the chloride has also been authenticated: monoclinic,
P 21/c,
a 12·832(2), b
54·24(1), c 18·519(8) Å, β
129·68(3)°; Z = 8
(R 0·065 for No 5672). No
bromide has been obtained; the iodide (2) is described as monoclinic,
P 21/n,
a 19·611(4), b
14·473(6), c 17·74(1) Å, β
98·28(3)°; Z = 4
(R 0·036 for No 6769). The
thiocyanate crystallizes from acetonitrile or pyridine as an
S-bonded form (3) isomorphous with the arsine analogue:
monoclinic, P
21/n, a
19·143(7), b 14·288(5),
c 18·694(6) Å, β 98·81(2)°;
Z = 4 (R 0·037 for
No 4482). From 2-methylpyridine, remarkably, a solvate
is obtained in which the thiocyanate is N-bonded (4):
triclinic, P-1,
a 27·261(5), b
14·767(3), c 13·319(1) Å, α
91·53(1), β 101·58(1), γ 92·29(2)°;
Z = 4 (R 0·045 for
No 6900). The cyanide is also monoclinic,
P 21/n,
a 19·442(7), b
14·267(3), c 17·741(6) Å, β
97·63(3)°, z = 4;
R 0·057 for No 2487. The
unsolvated 1 : 3 nitrate complex (6a) is monoclinic, P
21/n, a
19·602(5), b 14·455(1),
c 17·727(2) Å, β 97·19(2)°,
Z = 4; R was 0·034
for No 6522. The complex is isomorphous with the arsenic
and phosphorus analogues, being mononuclear
[(Ph3Sb)3Ag(O2NO)].
The ethanol solvate (6b) is triclinic,
P-1, a
13·352(5), b 14·548(9),
c 14·701(4) Å, α 81·64(4),
β 84·45(3), γ 75·32(4)°, Z
= 2; R was 0·058 for
No 4702. Ag-Sb range between 2·6980(8) and
2·843(3) Å in the precise determinations; Ag-X are
2·481(4) and 2·52(1) Å (the two chlorides),
2·757(1) (I), 2·533(3) (SCN),
2·21(1) (NCS), 2· 09(3) (CN),
2·377(7) Å (unidentate ONO2)
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXXI Synthesis, Spectroscopy and Structural Systematics of Some 1 : 2 Binuclear Adducts of Silver(I) Compounds with Triphenylarsine, [(Ph3As)2Ag(µ-X)2Ag(AsPh3)2], X = Cl, Br, I, SCN
Authors: Bowmaker Graham A. , Effendy  , Kildea John D. , Silva Eban N. de , White Allan H.
Published: August 2004

The syntheses and room-temperature single-crystal X-ray structural
characterization of binuclear 1 : 2 adducts formed between silver(I)
(pseudo-)halides, AgX, and triphenylarsine, AsPh3, for X
= Cl, Br, I, SCN (1)–(4), are described. The chloride (1),
obtained from 2-methylpyridine, is triclinic,
P-1, a
10·410(2), b 12·716(2),
c 14·196(6) Å, α 113·38(2),
β 109·41(2), γ 75·08(1)°, Z
= 1 (dimer); conventional R on
F was 0·037 for No 3979
independent ‘observed’ (I > 3σ(I)) reflections. The
bromide (2a), obtained from 2,6-dimethylpyridine, and iodide (3), obtained
from a mixture of AgI/saturated KI in MeOH solutions, are isomorphous,
monoclinic, P
21/c
a≈ 24·2, b ≈
13·9, c ≈ 20·2 Å, β ≈
109·5°, Z = 4 dimers;
R was 0·046 and 0·044 for
No 5670 and 6039 respectively. The thiocyanate (4) has a
similar cell, a 24·12(1), b
12·558(8), c 23·244(4) Å, β
110·11(3)°, Z = 4 dimers,
R being 0·044 for No 7956;
one of the thiocyanate ligands (which bridge in Ag-SCN-Ag mode) is disordered.
A second polymorph of the bromide (2b) (from a mixture of AgBr/saturated
KBr in H2O) is also monoclinic, P
21/c, a
14·121(8), b 25·577(3),
c 21·968(2) Å, β 125·54(3)°,
Z = 4 dimers (R was
0·047 for No 5715). Ag–As range between
2·568(1) and 2·633(1) Å throughout the series; in the
isomorphous bromide and iodide, values increase slightly:
2·578(1)–2·611(1), cf. 2·601(2)-2·633(1)
Å respectively. Ag–X are 2·568(2)-2·670(2) (Cl);
2·688(2)–2·715(2) (Br);
2·828(2)–2·856(1) Å (I); Ag-S, N for the ordered SCN
group are 2·646(3), 2·255(6) Å. A redetermination of
improved precision (R 0·035,
No 6030) is reported for the
triphenylphosphine/thiocyanate analogue. The far-infrared spectra of
[(Ph3As)2Ag(µ-X)2Ag
(AsPh3)2] show
v(AgX) bands at 185, 145 (X = Cl), 145, 130, 106
(X = Br) and 121 cm-1 (X = I). The
splittings and band widths reflect a decrease in the degree of distortion of
the Ag(µ-X)2Ag units from a symmetrically bridged
structure from X = Cl to I.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXIX Syntheses, Spectroscopy and Structural Systematics of Some (Solvated) 1 : 2 Binuclear Adducts of Copper(I) Compounds with Triphenylarsine, [(Ph3As)2Cu(μ-X)2Cu(AsPh3)2], X = Cl, Br, ONO2
Authors: Hart Robert D. , Bowmaker Graham A. , Kildea John D. , Silva Eban N. de , Skelton Brian W. , White Allan H.
Published: August 2004

1 : 2 Adducts of copper(I) chloride and bromide with triphenylarsine have been
obtained as chloroform- solvated dimers
[(Ph3As)2Cu(µ-X)2Cu(AsPh3)2].2CHCl3,
characterized by room-temperature single- crystal X-ray studies, monoclinic
C 2/c, a
≈ 21·4, b ≈ 17·9,
c ≈ 19·3 Å, β ≈ 92°,
Z = 4 dimers, conventional
R on F being 0·041 and
0·055 for No 3922 and 3130
independent ‘observed’ (I > 3σ(I)) reflections; the
halogen atoms of the dimers are disposed on crystallographic
2 axes, together with the associated hydrogen-bonded
pair of disordered chloroform molecules. The structures form an interesting
contrast with those of their silver(I)/phosphorus analogues, of similar
symmetry but with a and c
interchanged, as is the metal · · · metal axis
orientation which, in each case, lies parallel to the long crystallographic
axis. An unsolvated nitrate
[(Ph3As)2Cu(µ-O-ONO2)2Cu(AsPh3)2],
monoclinic, P
21/c, a
14·867(8), b 23·518(8),
c 21·86(1) Å, β 122·24(4)°,
Z = 4 dimers, R
0·056 for No 3447, is also
recorded, the structure being similar to that of its silver(I) bromide
analogue. The far-infrared spectra of
[(Ph3As)2Cu(µ-X)2Cu(AsPh3)2].2CHCl3
(X = Cl, Br) show v(CuX) bands at 195 and 153
cm-1 respectively. Shifts in the wavenumbers of the
CHCl3 vibrations which involve the hydrogen atom (or the
deuterium atom in the corresponding CDC13 compounds) are
in the direction expected for hydrogen bonding of the chloroform to the halide
ligand, and the magnitudes of the shifts in these and the corresponding
Ph3P/AgX complexes appear to be sensitive to the
degree of ionic character of the M-X bonds. A combined differential scanning
calorimetry/infrared study suggests that the chloroform disolvates are
converted into unsolvated compounds which have the same halogen-bridged
dimeric structures as the parent compounds, with v(CuX)
= 184, 141 cm-1 for X = Cl, Br
respectively.
Mannich Reaction Product of Quinolin-8-ol (Oxine) and its Antibacterial Activity
Authors: Faizi Shaheen , Siddiqui Bina Shaheen , Saleem Rubeena , Akhtar Farzana , Khan Khursheed Ali , Khan Shakeel Ahmed , Siddiqui Salimuzzaman , Parvez Masood , Choudhary M. Iqbal
Published: August 2004

Quinolin-8-ol (1) on reaction with 2,6-dichloroaniline and
m-nitrobenzaldehyde afforded 7-(α-hydroxy-
m-nitrobenzyl)quinolin-8-ol (2), which is an unusual
Mannich reaction product. The structure of (2) was determined by spectroscopic
and single-crystal X-ray diffraction studies. Preliminary antimicrobial
screening showed that (1) and (2) have activity against a large number of
Gram-positive and Gram-negative bacteria.