bluuebunny/crossref_metadata_2025 huggingface dataset:
Population Structure of Snow Gum (Eucalyptus pauciflora Sieb ex Spreng) Subalpine Woodland in Kosciusko National-Park
Authors: Barker S
Published: December 2005

Snow gum was sampled in 15 sites at altitudes from 1540 to 1820m. The population age structure
reflects the incidence of fire and grazing, which have affected the woodland since 1900. Evidence for
recruitment on three occasions prior to 1900 is given, and it is suggested that two of these may have
arisen as a result of fire. Whereas pre-disturbance stem densities calculated from remnants of previous
populations suggest densities of between 24 and 240 stems per hectare according to site, current stem
densities arising from flushes of regeneration this century are calculated as between 700 and 5550 stems
per hectare. In 1973, levels of failing stems within juvenile, mature and old subpopulations, while
variable, suggest that it may be 100-200 or more years before stem densities approach the calculated
pre-disturbance densities. The work raises park management issues: what structural forms of woodland
are appropriate in the Park; what effect allowing natural senescence to thin existing woodland will have
on fire hazard and other components of the ecosystem; the need for a long-term monitoring system.
The Ecology of Athrotaxis D. Don (Taxodiaceae). I. Stand Structure and Regeneration of A. cupressoides
Authors: Cullen PJ , Kirkpatrick JB
Published: December 2005

Athrotaxis cupressoides forms stands of varying size class and age class structure in the high subalpine
and alpine environments of Tasmania. As with some other southern hemisphere gymnosperms with
great longevity, A. cupressoides does not successfully regenerate in dense forest stands without disturb-
ance but does so in many open stands. Vegetative regeneration through root suckers occurs in many
such stands. Suckers are most frequent in bogs and least evident in blockstreams. There has been little
successful seedling or sucker regeneration in open stands in the east of the range of the species since
European occupation of the Central Plateau. Exclosure experiments and field observations show that
seedlings, suckers and adult foliage are heavily grazed by introduced placental and native marsupial
mammals.
The Ecology of Athrotaxis D. Don (Taxodiaceae). II. The Distributions and Ecological Differentiation of A. Cupressoides and A. selaginoides
Authors: Cullen PJ , Kirkpatrick JB
Published: December 2005

Athrotaxis selaginoides and A. cupressoides are potentially interbreeding species with partly overlapping
ranges. The two Athrotaxis species occur in a wide range of floristic types, with A. selaginoides being
concentrated in thamnic and implicate rainforest communities and A. cupressoides in open montane
communities. As is consonant with its distribution pattern and the cold resistance of its adult foliage,
A. cupressoides seedlings are more frost resistant than those of A. selaginoides. Preliminary experiments showed no difference between the two species in resistance to waterlogging or drought. However,
stand structure data indicate that A. selaginoides can survive better in shaded conditions than its
congenor. This pattern of ecological differentation is consistent with an origin by parapatic speciation.
Floral Initiation and Development in Helipterum roseum (Hook.) Benth. And Helichrysum bracteatum (Vent.) Andrews (Asteraceae)
Authors: Sharman KV , Sedgley M
Published: December 2005

Floral initiation and development in Helichrysum bracteatum and Helipterum roseum were investigated by scanning electron microscopy. The sequence of events in these two species was similar and occurred rapidly. Seven stages in apical development were identified, which were distinctive in both appearance and size. Stage 1 was a small vegetative meristem with 2-4 leaf primordia. Stage 2 (also vegetative) was characterized by a doubling in both height and diameter. A doming of the apical meristem signified the commencement of stage 3, and at the appearance of the first involucral bracts (stage 4) the apex had further tripled in height and doubled in diameter. This was followed by the appearance of floret primordia (stage 5). By the time the inflorescence buds were visible to the naked eye (stage 6) several rows of florets were present, and at anthesis (stage 7) the capitulum was covered with florets. During the transition from stage 4 to stage 5 a few developing primordia appeared to divide. The lower portion developed into a small involucral bract and the upper portion into a floret. The florets developed centripetally such that a range of developmental stages was present on the capitulum. The development of the individual florets involved the differentiation of perianth, anther, pistil and pappus hairs. Stage 4 was considered the point at which the apex was committed to flower.
Computer Modelling of Damping-Off Epidemics in Relation to Host Density and Number of Disease Foci
Authors: Mao YX , Chilvers GA , Burdon JJ
Published: December 2005

In a previous experimental study of post-emergence damping-off epidemics in populations of cress
seedlings, rate of advance ( A ) of spreading disease fronts and apparent infection rates ( r ) were measured
separately in relation to differences in host density. In this study, a computer model was built to simulate
those damping-off epidemics, with the aim of relating A and r. Over a range of host densities it was
found that r could be predicted from the known quantitative relationship between A and host density,
provided that the number of primary infection foci was also taken into account. Scrutiny of the earlier
experimental results revealed that the number of primary infection foci separately influenced the sub-
sequent infection rate. The importance of number of foci in this instance is attributed to the very steep
inoculum gradient characteristic of this disease, which limits inoculum transmission to plants around
the periphery of disease patches so that disease increase is controlled more by the sum of disease
perimeters than by the sum of diseased infectious plants as in air-borne diseases. It is expected that other
slow-spreading soil-borne diseases with steep inoculum gradients will follow this same pattern.
Eucalypts Are Susceptible to the Chestnut Blight Fungus, Cryphonectria Parasitica
Authors: Old KM , Kobayashi T
Published: December 2005

Eucalyptus camaldulensis, E. haemastoma, E, microcorys, E. punctata and E. robusta grown in
greenhouses in Japan were susceptible to infection by Cryphonectria parasitica, syn. Endothia parasitica.
A Cryphonectria sp. found on Eucalyptus in central Honshu was morphologically identical to
C. parasitica and caused cankers on the five eucalypts and Castanea crenata. Endothiella, the anamorph
of Cryphonectria. spp, and Endothia spp., was found on eucalypts in four field locations in Honshu.
The evidence suggests that eucalypts are infected in the field by C. parasitica in Japan. Accidental
introduction of the chestnut blight fungus into Australia could have serious consequences for the health
of native eucalypts, in addition to causing disease of cultivated chestnuts.
Cyclical Patterns of Regeneration in Subalpine Heathland Communities on the Bogong High-Plains, Victoria
Authors: Williams RJ , Ashton DH
Published: December 2005

In the subalpine tract of the Bogong High Plains, cyclical patterns of regeneration occur within open
heath and closed heath communities. In the Grevillea australis-Poa hiemata open grassy heath, most
Grevillea shrubs are at present mature or senescent. Beneath the foliage of these shrubs, and in their
canopy gaps, the dominant replacement species in the herb layer is snowgrass (Poa hiemata), and these
shrubs tend to be replaced by snowgrass as they senesce. In the Phebalium squamulosum-Grevillea
australis closed heath, both snowgrass and shrubs may occupy the senescent and gap phases of the
dominant shrubs. Grazing by free-ranging cattle appears to favour the recolonisation of such gaps by
shrubs rather than by Poa. In Prostanthera cuneata closed heath, regeneration in gaps was clearly
shrub-dominated, with little establishment of snowgrass. Some shrubs, such as Grevillea, are obligate
seed regenerators, whereas Phebalium and Prostanthera are capable of regeneration by both seed and
vegetative means, such as root stock and layering stems. The life cycle of the major shrubs, from
establishment to death, appears to require 30-50 years.
Pollination and Seed Set of Banksia spinulosa: Evidence for Autogamy
Authors: Vaughton G
Published: December 2005

The breeding system of Banksia spinulosa var. neoanglica in the New England National Park was
examined by excluding pollen vectors and hand pollinating inflorescences. Fruit set of xenogamous and
open inflorescences was greater than geitonogamous and autogamous treatments, although not all
differences were significant. No differences were found in the number of seeds per follicle or seed weight
between treatments. A reduced number of follicles and smaller seeds occurred in the apical third of
inflorescences in all treatments. This report of autogamous seed set contrasts with previous findings for
this species and indicates intra-specific variation in the breeding system.
Genesis of an Inverted Treeline Associated With a Frost Hollow in South-Eastern Australia
Authors: Paton DM
Published: December 2005

A catastrophic frost in the Bonang valley, Victoria (alt. 660 m), during Aug. 1982 caused severe damage to naturally occurring trees growing within a contour-related inversion layer. All eucalypts and acacias on the valley floor and up to 6 m above it on the lowest slopes were either killed outright or suffered complete crown loss. Between 6 and 25 m above the valley floor, tall Eucalyptus viminalis. trees escaped damage if their crowns were positioned well above the inversion layer. Neighbouring trees of the slightly shorter original codominant E. radiata were so severely damaged that they were either killed or survived crown destruction only by production of trunk epicormics. Despite being wholly positioned within the inversion layer, the shorter trees of E. pauciflora generally survived without much damage, although leaf injury continued to develop for several years in some trees. Results of the final assessment 5 yr after the frost indicate that the lowest surviving E. viminalis trees, together with severely damaged E. radiata. trees, now constitute an inverted treeline separating forest above from dead trees and grassland below. This treeline is related to the 666 m contour, 6 m above the valley floor, and forms a very abrupt boundary because of the predominance
of large undamaged trees of E. viminalis. The consequences of this rare catastrophic frost have implications for subalpine ecology in south-eastern Australia, especially the genesis and stability of inverted
treelines.
In vitro Propagation of Araucaria cunninghamii and Other Species of the Araucariaceae Via Axillary Meristems
Authors: Burrows GE , Doley DD , Haines RJ , Nikles DG
Published: December 2005

Stem segments with 3-5 leaf axils, excised from the upper portion of the mainstem of 2-year-old hoop
pine (Araucaria cunninghamii Aiton ex D. Don) seedlings, produced orthotropic buds from the concealed
axillary meristems when cultured on a basal medium (BM) of half-strength Murashige and Skoog
(MS) inorganic salts, the medium level of growth factors and amino acids of de Fossard, 20 g L sucrose
and 6.5 g/L agar. This procedure was also successful with A. balansae, A. bidwillii, A. colurnnaris,
A. hunsteinri, A. luxurians, A. montana, A. rulei, A. scopulorum and Agathis robusta and with stem
segments from orthotropic coppice shoots of juvenile morphology collected from the stumps of 20-year old
hoop pines felled near ground level. The hoop pine explants were highly sensitive to cytokinin; 1 μM
and 10 μM 6-benzylaminopurine caused the formation of distorted buds and total inhibition of bud
development respectively. Lofier concentrations (0.001-0.1 μM ) did not noticeably influence bud formation
or development. A low rate of multiplication was induced by reculturing the stem segments after
the excision of the initial shoots. New buds developed in the leaf axils of that part of the initial shoot
which remained attached to the primary stem explant.
Shoots derived from seedling and coppice cultures of hoop pine and seedling cultures of Agathis
robusta rooted in vitro on BM + 0.1-10.0 μM indole-3-butyric acid (IBA), but with only 5-20% success.
Up to 80% rooting was obtained if both hoop pine shoot types (i. e. from seedling and coppice cultures)
were cultured on modified BM (quarter strength MS salts, 10 μM IBA plus no agar) for 2 weeks, before
being transferred to a mixture of non-sterile peat and perlite or vermiculite and perlite, maintained under
a high humidity (90-95%). Plantlets were subsequently transferred to normal glasshouse conditions and
then to the field with less than 5% mortality. Thus hoop pine can be added to the relatively small
number of conifers for which the capacity to micropropagate juvenile and mature plants and successfully
establish their clones in the field has been demonstrated.
Germination and Morphology of Progeny From Controlled Pollinations of Eucalyptus nitens (Deane & Maiden) Maiden
Authors: Tibbits WN
Published: December 2005

The germination and morphology of progeny from interspecific and intraspecific controlled pollinations
on Eucalyptus nitens mothers were examined.
All interspecific hybrids were morphologically intermediate overall with respect to parental controls,
as determined by discriminant function analyses. Single univariate characters displayed additive inherit-
ance on 72% of the 154 occasions where differences amongst hybrids and parents were significant. The
degree of dominance of characters is discussed.
Compared with outcrossing, self-fertilisation resulted in lower seed viability and a higher incidence
of abnormality and mortality in developing E. nitens seedlings. Outcrossed progeny were generally
distinctly different from appropriate parental controls. Reciprocal crosses were very similar, indicating
no observable maternal effects.
Occurrence of Species of Aspergillus and Penicillium in Roots of Wheat and Ryegrass and Their Effects on Root Rot Caused by Gaeumannomyces graminis var. Tritici
Authors: Dewan MM , Sivasithamparam K
Published: December 2005

Aspergillus fumigatus, A. terreus, Emericella nidulans, E, quadrilineata, Penicillium aculeatum,
P. brevicompactum, P. chrysogenum, P. citreonigrum, P. corylophilum, P. fuscum, P. griseofulvum,
P. janthinellum, P. nigricans, P. purpurogenum, P. restrictum, P. turbatum, P. verruculosum,
Eupenicillium sp. and E. euglaucum were isolated from roots of wheat and ryegrass at seedling, tillering,
stem extension, milky ripe and ripe for cutting stages. Frequency of occurrence of species of Aspergillus
and Penicillium were higher in roots subjected to washing only and plated onto PDA or PDA amended
with lactic acid. In general, species of these two genera were common at the stem extension stage.
P. nigricans, P. janthinellum, P. griseofulvum, P. fuscum, Eupenicillium sp. and P. turbatum were isolated at a higher frequency than other species.
When introduced at 1% inoculum level A. terreus, P. fuscum, P. griseofulvum and P. nigricans
caused severe damage to wheat and ryegrass seedlings especially in sterilised Lancelin soil where they
reduced the fresh shoot and root weights of the hosts.
When these isolates were screened for antagonism towards Gaeumannomyces graminis var. tritici
(Ggt) or agar the strongest antagonism was shown by P. griseofulvum, A. terreus, P. nigricans,
P. fuscum and P. janthinellum, whereas other species of the two genera had little or no effect on Ggt.
The presence of A. terreus, P. griseofulvum or P. fuscum. with Ggt decreased root rot of wheat and
ryegrass caused by Ggt in sterilised and non-sterilised soil, while P. nigricans showed a similar effect in
non-sterilised soil only. However, none of the isolates tested would be suitable as biological control
agents.
Phenology, Reproductive-Biology and Seed Development in Four Rush and Sedge Species From Western Australia
Authors: Meney KA , Dixon KW
Published: December 2005

Four species of Restionaceae and Cyperaceae from the Mediterranean-type climate region of Western
Australia were studied to determine factor(s) limiting their reproductive performance. Ecdeiocolea
monostachya (Ecdeiocoleaceae), Lepidobolus chaetocephalus (Restionaceae), Restio aff. sphacelatus
(Restionaceae) and Mesomelaena pseudostygia (Cyperaceae) differed in the pattern of dry matter partitioning
and phenological patterns. All species were moderately efficient at remobilising dry matter
from senescing vegetative organs, maintaining constant tissue water to dry matter content in mature
organs over the study period regardless of soil moisture availability. In situ nutrient and water supplements
of study species did not elicit improved seed production or significant increases in dry matter
accumulation (except for current and old culms of E. monostachya and spikelets of L. chaetocephalus).
For all study species except L. chaetocephalus, seed production was low, while herbivore activity, insect
predation andlor infection by a smut (Tolyposporium lepidiboli) reduced seed production potential in
L. chaetocephalus and E. monostachya. Attempts at seed germination for all study species were not
successful. Extracted embryos from mature seed of all species cultured in vitro grew rapidly, providing
a reliable method for propagation of study species.
Secondary Succession in Post-Fire Scrub Dominated by Acacia verticillata (L'hérit) Willd at Wilsons Promontory, Victoria
Authors: Ashton DH , Chappill JA
Published: December 2005

Senescence and death of 30-year-old post-fire Acacia verticillata scrub in areas originally supporting
sclerophyll eucalypt forest were studied over a 6-year period at Wilsons Promontory, Victoria. The
potential for eucalypt regeneration was also examined. On drier sites, A. verticillata has been replaced
by drought-resistant Kunzea ambigua while on wet sites it has been replaced by waterlogging-tolerant
Melaleuca ericifolia. In mid slopes A. verticillata is regenerating from soil seed in gaps in the field layer
of Pteridium esculentum and Goodenia ovata and forming a patchy, uneven-aged stand. The composition
of the mid-slope community is determined by the relative resistance of species to browsing and
grazing. The failure of eucalypts to reclaim the scrub areas at this critical time has been due to poor
seed crops, seed harvesting by ants and intense selective browsing. Exclosure plots have demonstrated
the importance of herbivory in modifying this vegetation and indicate potential means of reafforestation
without the intervention of fire.
The Ecology of Thelymitra epipactoides F Muell (Orchidaceae) in Victoria, Australia, and the Implications for Management of the Species
Authors: Calder DM , Cropper SC , Tonkinson D
Published: December 2005

The habitats of existing populations of Thelymitra epipactoides in Victoria, Australia, are described
according to the physical and biotic environments. The orchid is confined to a range of heathland
communities usually near the coast. The species seems to prefer the more open, previously disturbed
sites within the community. Following a discussion of the particular habitat requirements of
T. epipactoides, some guidelines for the conservation management of the species are outlined.
The Breeding Biology of Epacris impressa. Is This Species Heterostylous?
Authors: Obrien SP , Calder DM
Published: December 2005

The suggestion that Epacris impressa is heterostylous is discussed in relation to an examination of the
morphological characteristics and the incompatibility system of the species. The conclusion is reached
that, although the style length is variable, the species does not exhibit either the full morphological or
incompatibility syndromes associated with heterostylic systems. An interpretation is given suggesting
E. impressa may represent the early stages of the evolution of heterostyly. The results of self- and crosspollination
experiments are presented which confirm the view that E. impressa is a species which is
essentially self-infertile, but a significant minority of individuals within each population demonstrate
self-fertility.
Effects of the Cessation of Grazing on the Grasslands and Grassy Woodlands of the Central Plateau, Tasmania
Authors: Gibson N , Kirkpatrick JB
Published: December 2005

The response of grassy vegetation to exclusion from grazing was found to be related to a major productivity
gradient in the central highlands of Tasmania. All sites showed a trend toward increased
structural complexity, a decrease in bare ground and a decrease in species richness when grazing was
excluded. However, the effect was much more pronounced at sites of high productivity. These findings
support the theory that species richness is a function of both disturbance and the rate of competitive
exclusion (site quality), and support suggestions that stock grazing is inappropriate above 1000 m on the
Central Plateau.
The Structure and Histochemistry of the Nectary and Anther Secretory Tissue of the Flowers of Thryptomene calycina (Lindl) Stapf (Myrtaceae)
Authors: Beardsell DV , Williams EG , Knox RB
Published: December 2005

Flowers of Thryptomene calycina contain two types of secretory tissue. Nectaries of the floral tube
secrete a nectar rich in fructose and glucose, probably through the numerous stomata in the epidermis.
The secretory cells are densely packed and have few vascular connections. The five anther connectives
each terminate in a gland, which at anthesis contains large, thin-walled cells. The gland contains a
hydrophobic material which stains positively for lipids and probably contains phenolics. This material
is secreted through a pore at the end of the gland where it collects and mixes with pollen to form a food
source for insects. This dual secretion of food materials would ensure that a wide range of pollinating
insects visit the flowers.
The Structure of the Column in Stylidium
Authors: Findlay N , Findlay GP
Published: December 2005

In the genus Stylidium, the style and filaments of the flower are fused into a single column. In most
species the column, when stimulated mechanically, undergoes a fast firing movement followed by a slow
resetting movement. This movement is produced by changes in shape of a normally curved region of
the column, the bend. In a wide range of species, the bend has a specialised anatomy and consists
essentially of a longitudinal central layer of cells with two distinctive multi-celled layers of thick-walled
cells on either side. The thick-walled cells are rich in cytoplasm with amyloplasts and vacuoles of varying
sizes, and have non-lignified walls whose cellulose fibrils are arranged approximately transversely. Within
the bend, the phloem occurs as discrete small groups of cells separated by some distance from the xylem.
In species from the subgenus Centridium both the morphology and the internal structure of the bend
differ somewhat from those in most species of Stylidium, and in two species of Stylidium with nonmoving
columns, the characteristic cellular anatomy of the bend is entirely absent.
The specialised anatomy of the cells and tissues in the bend are clearly associated with the movement
of the column. Changes of shape and size of these cells are almost certainly responsible for the change
in shape of the bend.
Reproductive Function in the Mimosoid Legume Acacia retinodes: Ultrastructural and Cytochemical Characteristics of Stigma Receptivity
Authors: Knox RB , Kenrick J , Jobson S , Dumas C
Published: December 2005

The stigma of Acacia retinodes is receptive from the moment the flower opens (female phase). Receptivity,
assessed in terms of pod set, is highest at flower opening, and lowest the following day (male
phase). Stigma receptivity is associated with the acquisition of a heterogeneous stigma exudate, the
components of which are secreted sequentially during differentiation. Cytochemical probes have
tentatively identified the principal components as unsaturated and saturated lipids, free fatty acids,
flavonoid aglycones, carbohydrates, proteins and phenolic compounds.
The onset of male phase in unpollinated stigmas is associated with a breakdown of the plasma
membrane and organelle membranes of stigma cells, and subsequently a browning reaction.
Floral Morphology of Eucalyptus melliodora A. Cunn. ex Schau. And Comparisons With Other Eucalypt Species
Authors: Moncur MW , Boland DJ
Published: December 2005

The important phases of floral development in E. melliodora from bud initiation to anthesis and style abscission are documented by means of scanning electron micrographs. Thirteen phases of bud development from first indication of operculum abscission to style abscission are presented, as well as the timing and duration of each phase. Anther dehiscence commences prior to flower opening and no pollen grains were observed on flowers 2 days after opening. Secondary transportation of pollen after deposition is possible. Nectar secretion did not commence until after pollen was shed and the stigma became receptive. Although individual flowers were protandrous, there was some overlap within a single inflorescence between pollen shed and the 'wet stigma' phase, suggesting that geitonogamy was possible. The style did not increase in length following anthesis, a common feature in Eucalyptus, leaving the stigma in close proximity with the anthers. There was a graduation in filament length from the outer
to inner whorls. The innermost anthers produced the most pollen grains while the outermost were
staminodal.
There was considerable difference between the number of stamens (71-312), staminodes (0-83) and
pollen grains per anther (643-1790) found in the six species examined. Stamen length in all species
increased across the staminophore from 1.82-6.99 mm in the inner whorl to 4.84-12.61 mm in the
outer whorl.
Geographic Patterns of Genetic Diversity in Karri (Eucalyptus diversicolor F. Muell.)
Authors: Coates DJ , Sokolowski RE
Published: December 2005

Karri (Eucalyptus diversicolor) is a large dominant timber tree which occupies a limited area of high
rainfall in south-western Australia. The level and geographic distribution of genetic vadation were
studied at 16 polymorphic allozyme loci. Geographical trends were observed only at the Adh-1 locus
with the fastest allele restricted to the westerly end of the species distribution. The mean number of
alleles per locus per population (A = 1.60) and the expected panmictic heterozygosity (He = 0.15) are
generally low when compared with most other eucalypts. Much of the genetic variation in karri occurs
within populations (Hs = 0.270) rather than between (Gst = 0.092), However, certain outlying populations exhibit noticeable levels of genetic divergence from the main karri forest, whereas no significant
differentlation was found between populations from different river catchments within the main forest.
Strategies for the conservation of genetic resources of karri are discussed in the light of these findings.
The lack of genetic differentiation between the southern coastal outliers and the main forest indicates
more recent separation than outlying populations to the north-east and west which probably separated
from the main distribution as aridity increased from about 5000 B.P. Differences in the average fixation
index F between populations, although not always significant, were sufficient to suggest that there could
be real differences in the level of outcrossing between some populations.
Trichomes From the Foliage of Some Australian Acacias
Authors: Boughton VH
Published: December 2005

Five types of non-glandular and six types of glandular hair are described from 148 Australian species
of Acacia representing all sections of the subgenera Phyllodineae and Acacia which occur in Australia,
One hair type was found only on species inhabiting the arid interior. Some tentative links between hair
types and the taxonomic sections are established,
A Cline in Genetic Diversity in River She-Oak Casuarina cunninghamiana
Authors: Moran GF , Bell JC , Turnbull JW
Published: December 2005

Twenty populations of Casuarina cunninghamiana Miq. covering its large geographic range were
used in a study of genetic diversity. Genetic variation was measured by analysing 19 allozyme loci
using 50 seedlings from each of the populations. The overall genetic diversity (HT = 0.287) in
C. cunninghamiana is high compared to many other plant species. A significant fraction (26.4%) of
the total genetic diversity could be apportioned among populations. This genetic differentiation between
populations was not random. Populations in the eastern part of the range had high correlation
(r = 0.91) of genetic diversity with latitude and this involved changes in allelic frequencies at several
loci. At the population level, there was a significant positive correlation between genetic diversity and
1 year height growth. The western population from King River in the Northern Territory was very
distinct genetically from all the other populations and this supported previous suggestions that the northwest
part of the range is occupied by a different race of the species.
Phenology of Eucalyptus marginata on Sites Infested With Phytophthora cinnamomi
Authors: Davison EM , Tay FCS
Published: December 2005

The phenology of Eucalyptus marginata (jarrah) was followed at three sites, Churchmans, Karnet and
Ross, in the high rainfall zone of the jarrah forest for a minimum of 3 years. On each site, trees growing
in an area infested with the soil-borne, pathogenic fungus Phytophthora cinnamomi (dieback area) were
compared with trees of similar diameter in the adjacent, uninfested forest (healthy area).
Phenology of jarrah on these dieback sites did not follow a consistent pattern. In the dieback area
at Churchmans, the cambium was active more often, and trees had young leaves in their crown more
frequently than trees in the healthy area, while at Karnet the reverse occurred. This is consistent with
growth measurements. At Ross, in the dieback area, the cambium was active less often but young leaves
were seen more frequently than in trees in the healthy area.
The trees did not flower every year. At Ross flowering started in early October while at Karnet and
Churchmans it started at least 1 month later. New leaves were produced intermittently during autumn
and winter while the main leaf flush occurred in spring and summer. Data from all years showed that
the leaf flush started earlier at Ross than at Karnet and Churchmans. The cambium was intermittently
active throughout the year with most trees growing in late autumn, winter and spring.
Observations of stem growth following unseasonable summer rainfall suggest that cambial activity
is triggered by high, surface soil moisture, but only if soil aeration is adequate. It is unlikely that timing
of the main leaf flush and flowering are determined solely by temperature, soil moisture or photoperiod.
Germination of the Salt-Tolerant Grass Diplachne fusca. I. Dormancy and Temperature Responses
Authors: Morgan WC , Myers BA
Published: December 2005

The germination of the salt-tolerant grass Diplachne fusca (L.) Beauv. was investigated because of its
potential as a pasture species to be used in the reclamation of salt-affected land. Fresh seed was dor-
mant. Dormancy was not broken by stratification, but gradually broke down during air-dry storage,
indicating an after-ripening period of at least 1 year. The germination of germinable stored seeds at
various temperature regimes (combinations of day and night temperatures between 11 and 31°C) was
assessed on a thermogradient plate. The germination after 21 days was greatest at high temperatures
(40-90% when both day and night temperatures were between 24 and 31°C, either constant or alter-
nating). Germination was completely inhibited when both day and night temperatures were 5 18.5°C.
Germination percentage was more strongly correlated with night than with day temperature. Seeds for
which dormancy had been broken by scarification were capable of germinating at lower temperatures
(19% germination at 11°C) than stored seeds. From the observed temperature dependence of germination and the mean daily maximum and minimum temperatures recorded at Tatura and Deniliquin
(latitudes 36° 26̸2S. and 35° 32̸2S. respectively), it is expected that germination in the field, in the Riverine
Plain of south-eastern Australia, would be limited to the summer months (December-February).
Germination of the Salt-Tolerant Grass Diplachne fusca. II. Salinity Responses
Authors: Myers BA , Morgan WC
Published: December 2005

The responses -of germination of the salt-tolerant grass Diplachne fusca (L.) Beauv. to salinity and
various temperature regimes are described. At temperatures of 30/20°C (12 h light and dark periods),
final germination was 70% in distilled water, decreased to 50% in 175 mol m-3 NaCl (π = - 0.8 MPa)
and 7% in 380 mol m-3 NaCl (π = -1.8 MPa). Increasing salinity from 0-130mol m-3 NaCl
decreased the final germination percentage, but did not modify the threshold temperatures (day or night
temperature > 27°C) at which germination occurred. Presoaking in distilled water or 1% CaCl2· 2H20
solution did not significantly affect the final germination percentage of seeds which were subsequently
placed in solutions with a range of salinities from 0-210 mol m-3 NaCl (*#960 = 0 to - 1.0 MPa). How-
ever, addition of CaCl2 to NaCl solution increased the final germination percentage compared with that
in pure NaCl solution. Presoaking in concentrated (400 mol m-3) NaCl solution caused a decrease in
subsequent germinability of 20 or 40% in 0 and 40 mol m-3 NaCl, respectively. Under field conditions
(in soil with mean daily maximum temperature of 33°C and mean daily minimum temperature of 15°C),
rates of seedling establishment were similar (16% of seed sown) in soils irrigated with 0 or 50 mol m-3
NaCl, and were 1% in those irrigated with 100 mol m-3 NaCl.
The inhibition of germination in NaCl solution was largely an osmotic effect since there was a similar
reduction in the final germination percentage in iso-osmotic solutions of NaCl and mannitol. However,
the proportion of seeds germinating in NaCl solution was enhanced by adding calcium. The inhibition
of germination was greater in sulfate solutions compared with that in chloride solutions and, to a lesser
degree, in potassium compared with sodium solutions.
The practical implications of our results are discussed. The incorporation of gypsum into the soil
and measures to leach salts from the topsoil are recommended before D. fusca is sown on saline land.
Geographical Distribution of C4 Acid Decarboxylation Types and Associated Structural Variants in Native Australian C4 Grasses (Poaceae)
Authors: Prendergast HDV
Published: December 2005

The native Australian C4 grass (Poaceae) flora is estimated to comprise 347 (57%) NADP-ME (NADP-
malic enzyme), 193 (32%) NAD-ME (NAD-malic enzyme), and 65 (11%) PCK (PEP carboxykinase)
type species. All C4 types are best represented in northern tropical Queensland, within the megatherm
seasonal (summer) rainfall bioclimate of Nix. NADP-ME species are numerically dominant in 48 out
of 73 State and Territory subdivisions, including 23 wholly or partly within the megathermlmesotherm
arid bioclimate which closely corresponds to the arid and semiarid zones covering c. 80% of Australia.
NAD-ME species numbers are proportionately at their highest in this bioclimate; PCK species may be
the most dependent there on high soil moisture availability. The extent of the megatherm seasonal
bioclimate is parallelled by the distribution of most PCK species and of many species of all C4 types
with a suberised lamella in the cell walls of their 'photosynthetic carbon reduction' (or Kranz) tissue.
Whilst the physiological reasons for these correlations are unknown, it is clear that C4 type alone is
neither the sole determinant of geographical distribution nor necessarily always an adaptation to a
particular bioclimatic regime. Taxonomic, ecological and historical factors in relation to C4 type distribution are discussed.
The Growth and Development of Caltha introloba F. Muell. I. The Pattern and Control of Flowering
Authors: Wardlow IF , Moncur MW , Totterdell CJ
Published: December 2005

The floral development of Caltha introloba F. Muell. was surveyed in the short alpine herbfield areas
located in the vicinity of Charlottes Pass, in the Kosciusko National Park. This study included a detailed
examination, by scanning electron microscopy, of changes occurring at the shoot apex. Floral initiation
occurred in mid summer (January) and flowers were fully developed and in many instances ready to shed
pollen, before the first snow fall in late autumn (May). The flowers generally remained closed until after
the snow melted in spring (October), although some opening did occur under the snow if this remained
until late in the year (mid November). Seed development was normally complete towards the end of
summer (late January to February).
Controlled environment studies demonstrated that floral initiation and development were favoured
by long days and high irradiance. These factors may represent important controls in the field where
floral initiation occurs as daylength and irradiance reach their maximum levels. Also it was shown
experimentally that there is a cold requirement before the flowers, that are otherwise fully developed,
will open. This requirement should ensure that premature opening will not occur in autumn.
Effects of Season and Harvesting Treatments on Soluble-Sugar and Starch Levels in Eucalyptus obliqua and E. globulus subsp. bicostata Roots, and Implications for Armillaria Control
Authors: Tomkins IB , Kellas JD , Squire RO
Published: December 2005

Seasonal variations in starch and soluble sugar in root wood of standing trees and stumps of messmate
stringybark (Eucalyptus obliqua) and Victorian blue gum (E. globulus subsp. bicostata) were measured
for 2 years in four mature stands at Mount Cole, Victoria. Previously established seasonal variations
were confirmed for E. obliqua standing trees, and similar patterns were established for E. globulus
subsp. bicostata in the first year of the study. E. globulus subsp. bicostata had higher starch reserves
but similar sugar reserves to E. obliqua.
Selection, shelterwood and clearcutting at the beginning of the second season had no effect on the
starch and sugar reserves of retained trees. However, starch levels for stumps declined and appeared
to be converted to sugars as the latter were maintained at normal levels, and they continued to show
a seasonal variation for at least 12 months after cutting. There is little or no scope for manipulating
the food base for Armillaria by varying the harvesting treatment and/or the season of treatment.
Phosphorus Nutrition of Seedlings of the Waratah, Telopea speciosissima (Sm) R.Br. (Proteaceae)
Authors: Grose MJ
Published: December 2005

Seedling waratahs, Telopea speciosissima (Sm.) R.Br., were grown in acid-washed, phosphate-deficient
sand in a glasshouse for 14 weeks under ten phosphate regimes from 0 to 31 mg P/kg soil.
Root length increased at the lower levels of applied phosphate, but the dry weights of roots did not,
indicating thinner roots at low phosphate levels. Adding phosphate above a level of 0.6 mg P/kg soil
increased dry matter in shoots and leaf area. Phosphate concentrations in the youngest fully expanded
leaf (YFEL) ranged from 0.06% at deficient levels of applied phosphate to 0.4% at the optimal growth
level of 3.1mg P / kg soil. Toxicity symptoms were present at phosphate concentrations in shoots of
4.7%.
Cluster roots were found with levels of phosphate addition from 0-7.8 mg P/kg soil, and their
numbers increased as phosphate was increased from deficient to low levels, and decreased where applied
phosphate was adequate for plant growth.
Species Richness of Sclerophyll (Heathy) Plant Communities in Australia ̵2 the Influence of Overstorey Cover
Authors: Specht RL , Specht A
Published: December 2005

The species richness (number of vascular-plant species per unit area) of sclerophyll (heathy) plant communities is examined from south-east Queensland to south-west Western Australia. The species richness
of communities of heathy open forest, heathy open scrub, dry heathland and wet heathland is consist-
ently similar throughout southern Australia and decreases from dry heathland (on laterite, coastal and
inland localities) to heathy open forest, heathy open scrub and wet heathland.
Investigation of related microcommunities at Cooloola, Stradbroke Island, Ku-ring-gai Chase and
Wilsons Promontory indicates that species richness decreases linearly as overstorey cover increases. In
post-fire succession on Stradbroke Island heathy woodland and Dark Island heathland, species richness
declines linearly as overstorey cover increases during the regeneration of the community. The appli-
cation of limiting fertiliser to Stradbroke Island heathy woodland and Dark Island heathland increases
the rate of development of overstorey cover, with a simultaneous decrease in species richness.
Species richness of the understorey strata of plant communities appears to be inversely related to the
rate of development of foliage projective cover in the overstorey. If an environmental or biotic factor
inhibits or retards the development of overstorey cover, the understorey increases in species richness.
Conversely, if any environmental or biotic factor accelerates the development of overstorey cover, the
understorey species show a reduction in species richness.
Germination and Phenology of Seven Introduced Thistle Species in Southern Australia
Authors: Groves RH , Kaye PE
Published: December 2005

Seeds of seven introduced thistle species, common and widespread in southern Australia, were germi-
nated over a range of different day!night temperatures and water potentials. The thistles were Carduus
nutans L. (nodding), C. pycnocephalus L. and C. tenuiflorus Curtis (slender), Carthamus lanatus L.
(saffron), Cirsium vulgare (Savi) Ten. (spear), Onopordum aff. illyricum (illyrian) and Silybum
marianum J. Gaertn. (variegated).
Fresh seed of all thistle species germinated over a wide temperature range (15/5° to 40/30°C).
Differences between taxa were expressed mainly at low temperatures (15/5° and 15/0°C), at which
C. pycnocephalus germinated well and Onopordum only minimally. Germination of C. lanatus seeds
was the most sensitive to moisture stress and that of C. nutans and C. vulgare the least. Radicle
elongation of germinating seedlings differed at different water potentials, with C. tenuiflorus being the
most sensitive to low water potential and that of C. lanatus the least, even at a water potential of
- 1.5 MPa.
The seven thistle species were separated into three groups based on the patterns of their phenological
responses over two seasons when grown in a common environment. Carduus pycnocephalus and
C. tenuiflorus behaved as short-season annuals, C. vulgare and Onopordum showed a strongly biennial
response, and the other species were annual except for C. nutans, which behaved as an annual or a
biennial depending on time of establishment.
We conclude that the differences in germination responses to temperature and water potential
between the different introduced thistles are minor. In combination with the major differences in phe-
nology revealed in this study some of these differences may help to explain the predominance of the seven
thistles in different regions of southern Australia. Other factors will largely determine their weediness
in any one region.
Foliar Frost-Resistance of Some Evergreen Tropical and Extratropical Australasian Nothofagus Species
Authors: Read J , Hope GS
Published: December 2005

Foliar frost resistance was compared in the evergreen Australian Nothofagus species, N. cunninghamii
(Hook.) Oerst. and N. moorei (F. Muell.) Krasser, and the New Guinea species, N. carrii Steenis, N.
cf. carrii Steenis, N. cf. crenata var. sapeii Steenis, N. grandis Steenis, N. perryi Steenis, N.
Pseudoresinosa Steenis and N. pullei Steenis. The order of frost resistance after hardening treatments
was N. cunninghamii > N. moorei > New Guinea species, with T50 values (temperature at which 50%
tissue damage occurs) ranging from 11.4�C in N. cunninghamii to -5.7� C in N. grandis and N. cf.
crenata var. sapeii. Northern species showed a lower frost resistance than southern species, including
N. moorei plants collected from a site with an apparently cooler climate than one population of N.
Cunninghamii. The southern species increased in frost resistance by 2.1-3.6� C. N. pullei, N.
Pseudoresinosa and N. perryi increased in frost resistance after the hardening regimes by 1.1 -1.5� C,
but the other New Guinea species showed no appreciable increase in frost resistance after the artificial
hardening regime of 2°C nights and little increase after natural hardening. The results are discussed in
relation to the geographic and climatic range of these species.
Effects of Rabbit and Kangaroo Grazing on Two Semi-Arid Grassland Communities in Central-Western New South Wales
Authors: Leigh JH , Wood DH , Holgate MD , Slee A , Stanger MG
Published: December 2005

The effects of rabbits and kangaroos, and rabbits alone, on the biomass and species composition of a
native grassland dominated by Stipa nitida/nodosa, Danthonia caespitosa and Aristida contorta, and
a grassland dominated by the exotic species Hordeum glaucum, Vulpia spp., Medicago laciniata and the
native Erodium crinitum growing at Yathong Nature Reserve in central New South Wales was monitored
between 1979 and 1985. Rabbits generally favoured the grassy component; kangaroos also favoured
grasses but less so. Changes in non-grass species composition due to grazing was generally insignificant.
Changes in species composition due to seasonal differences in rainfall was highly significant. No new
species appeared on plots exclosed from grazing for 10 years, suggesting that the grazing by livestock,
rabbits, and kangaroos in the past has determined the present species composition. The annual biomass
consumption by rabbits averaged over 6 years was 100-200 kg ha-1, which is equivalent to reducing the
carrying capacity by one sheep for every 2-4 ha rabbit-infested area. In the native grassland the spatial
pattern of rabbit grazing, as indicated by faecal pellet distribution, biomass removal, and percentage
of 'unpalatable' species in the pasture, shows greatest grazing pressure to be within 50 m of the warren,
grazing intensity dropping off from there to 300 m the greatest distance studied. From the start of the
study 'palatable' species, especially grasses, were at their lowest density within 50 m of the warren; this
appeared to be a historical effect of grazing. No patterns were discernible in the pasture dominated by
introduced species. Little change in species composition of these grasslands can be expected under a
wide range of grazing pressure, except close to rabbit warrens.