bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth Habits and Trellis Requirements of Climbing Palms (Calamus spp) in North-Eastern Queensland
Authors: Putz FE
Published: December 2005

Calamus moti and C. australis in tropical forest on the Atherton Tableland, Queensland, Australia, climb with the aid of long whip-like flagella covered with sharp hooks. Stiff stems and long flagella allow climbing palms to span larger gaps between successive supports than other types of climbers. Furthermore, recurved hooks on the flagella serve as a ratchet-like mechanism that draws climbing palms closer to supporting plants. Although both palm species climbed up through closed canopy forest, they were more abundant on treefall gap margins. Many gap-edge climbers survived after their supporting trees fell and grew back upwards on gap-edge trees. Once in the canopy, the climbing palms avoided growing up and out of the tops of their supporting trees through the combined effects of decreased internode length and downward slippage of the dangling stem.
Response to Salt and Waterlogging Stress of Ten Taxa of Acacia Selected From Naturally Saline Areas of Western Australia
Authors: Craig GF , Bell DT , Atkins CA
Published: December 2005

Ten taxa of Acacia were selected from areas of moderate to high soil salinity (electrical conductivities
of saturated soil paste extracts (ECe) between 1000 mS m--1 and 4800 mS m-1 at 50-600 mm depth) and
sodicity to test the tolerance of young, symbiotic plants to increasing levels of salinity both with and
without waterlogging. Nodulated plants, 3 months old, were grown in glasshouse experiments which
consisted of four treatments: non-saline drained control (12 weeks); saline drained (12 weeks); non-saline
waterlogged (5 weeks); and saline waterlogged (5 weeks).
Acacia cyclops, A. brumalis, A. redolens (Ravensthorpe) and A. aff. lineolata had 100% survival
after 12 weeks irrigation with saline solution (final ECw = 9500 mS m-1). Generally, the species tested
were sensitive to waterlogging with A. patagiata, A. cyclops and A. brumalis being the most sensitive,
having 19-44% mortality with no salt in the solution. The combined treatment of salt and waterlogging
greatly increased the mortality of plants, with four species having > 70% dead after 5 weeks treatment
(ECw = 3900 mS m-1). A. aff. lineolata and A. mutabilis subsp. ,stipulifera were highly tolerant of salt
plus waterlogging, with 100% and 96% survival respectively.
In salt plus waterlogged treatments, Na+ concentration in phyllodes of all taxa exceeded (0.37-2.13 mmol g-1 dry wt) that taken up by plants in freely drained salt treatments (0.03-0.42 mmol g-1 dry
wt). Taxa with the slowest rates of growth tended to accumulate the highest concentrations of Na+ in
the uppermost phyllodes.
Provenances of A. redolens and A. patagiata collected from sites of high soil salinity (ECe > 2200
mS m-1) had less than half the Na+ concentration in uppermost phyllodes (0.22 mmol -1 dry wt) at
the termination of the salt treatment, compared with provenances of the same species collected from
moderately saline areas (ECe = 1100 mS m-1). This indicates that Acacia provenances collected from
the most saline sites had greater potential to survive high levels of external salinity in the longer term
than those from less saline sites.
Effects of sodium chloride on seed germination and growth of two Chinese desert shrubs, Haloxylon ammodendron and H. persicum
(Chenopodiaceae)
Authors: Tobe Kazuo , Li Xiaoming , Omasa Kenji
Published: December 2005

The effects of sodium chloride (NaCl), polyethylene glycol-6000, temperature
and light on germination and the effects of NaCl on growth were investigated
in two Chinese desert shrubs, Haloxylon ammodendron
(C.A.Mey.) Bunge and H. persicum Bunge ex Boiss. et
Buhse. Both species occur in non-saline sand dunes;
H. ammodendron also occurs in saline land, although it
is not dominant there. Percentage germination of
H. ammodendron and H. persicum in
–3.0 MPa (667 mmol kg –1 ) NaCl was 91 and
64%, respectively. Hydroponic culture of each species for c. 3 months
with NaCl solutions of 0, 200, 400 and 600 mmol kg
–1 showed that the survival of
H. ammodendron was highest (82.3%) at 400 mmol kg
–1 NaCl, while that of
H. persicum decreased with increasing NaCl concentration
and was low (11.1%) at 400 mmol kg –1 NaCl.
Sodium concentration in shoot tissues of 99-day-old seedlings grown at 400
mmol kg–1 NaCl exceeded 1000 mmol kg
–1 in both species, while Na concentration in
non-transpiring young seedlings grown in 400 mmol kg
–1 NaCl was 240 and 350 mmol kg
–1 for H. ammodendron
andH. persicum, respectively. The results indicate that
both species have relatively low adaptability to salinity at the older
seedling stage compared with that at the germination and young seedling stage,
and that H. ammodendron shows higher adaptability to
salinity at the older seedling stage than H. persicum.
It was concluded that salinity adaptability in the later developmental stage
of these species determines their distribution with respect to salinity.
Reduction of fertile regenerants from protoplasts of Triticum tauschii (Coss.) Schmal.
Authors: Afshar-Sterle Shoukat , Kollmorgen James F. , Fincher Geoffrey B.
Published: December 2005

Four suspension cell lines generated from two accessions of
Triticum tauschii (Coss.) Schmal.
(Aegilops squarrosa, 2n =
2x = 14, DD genome) were used to develop an
efficient protocol for producing fertile regenerants from protoplasts.
Protoplasts were isolated from each cell line by incubating fine cell
aggregates (<500 µm in diameter) in a solution containing 3%
Cellulase ‘Onozuka’ RS, 0.5% Macerozyme R10 and 0.2%
Pectolyase Y23. Cell division occurred when the protoplasts were cultured at a
density of 1.0–1.5 x 106 protoplasts
mL–1 in half-strength MS medium supplemented with
1.1 mg L–1 2,4-dichlorophenoxyacetic acid (2,4-D),
0.6 M glucose and 1.2% agarose. The first cell divisions were observed
after 5–7 days. Cell colonies were observed after 14 days and these grew
quickly into large clumps when transferred to half-strength MS medium
supplemented with 2.2 mg L-1 2,4-D, 30 g
L–1 sucrose and solidified with 0.25%
Phytagel. The colonies produced somatic embryos within 21–28 days of
transfer to this medium. Somatic embryos were transferred to hormone-free MS
medium for regeneration into plantlets. Although many regenerants produced
shrivelled seeds, 9 of 16 were fertile and produced normal seeds.
Fire-stimulated rainforest seedling recruitment and vegetative regeneration in a densely grassed wet sclerophyll forest of north-eastern Australia
Authors: Williams Paul R.
Published: December 2005

Details of plant regeneration, combined with soil seedbank data, are
documented for a densely grassed wet sclerophyll forest in north-eastern
Australia. The following two hypotheses were tested: (1) that established
individuals of rainforest pioneer species are killed by low to moderate
intensity fires and (2) that seedling recruitment of these species is evenly
distributed throughout the intervals between fires.
Both the sclerophyll and rainforest pioneer species displayed strong
regenerative abilities as a response to low or moderate intensity fires. Most
of the rainforest pioneer species were not killed by two recent fires but
vegetatively regenerated. Alstonia muelleriana showed
fire-enhanced vegetative expansion via root suckering. Both the sclerophyll
and rainforest pioneer species were found to recruit seedlings primarily as a
pulse in the first year or two after a fire, with limited recruitment after
longer intervals between fires. This is consistent with suggestions that grass
competition may limit tree recruitment. The germinable soil seedbank was
dominated by rainforest pioneers, herbs and grasses, with heat treatment of
the seedbank enhancing seed germination of two rainforest pioneer species.
These results demonstrate the ability of rainforest pioneers to exploit the
post-fire environment and indicate the complex nature of rainforest boundary
dynamics. Further research into tropical rainforest expansion is required to
examine the effects of fire regimes on vegetative and seedling regeneration
across a range of sites.
Molecular systematics of the Leptospermum suballiance (Myrtaceae)
Authors: O'Brien Marcelle M. , Quinn Christopher J. , Wilson Peter G.
Published: December 2005

Two chloroplast regions, the
matK gene and the atpb
–rbcL intergenic spacer, were sequenced for 31
species of the Leptospermum suballiance. Both regions
proved to be highly informative of relationships within the suballiance.
Cladistic analyses confirm the monophyly of the
Leptospermum suballiance but not of the
Leptospermum alliance. Neither
Agonis nor Leptospermum is
monophyletic and there is no support for the distinctness of
Angasomyrtus from Kunzea. The
utility of the rps16 intron for this group was also
investigated but further work on this region was discontinued because of
primer incompatibility.
Composition, leaf area index and standing biomass of eucalypt open forests near Darwin in the Northern Territory, Australia
Authors: O'Grady A. P. , Chen X. , Eamus D. , Hutley L. B.
Published: December 2005

Savanna communities dominate the wet–dry
tropical regions of the world and are an important community type in monsoonal
northern Australia. As such they have a significant impact on the water and
carbon balance of this region. Above the 1200-mm isohyet, savanna’s are
dominated by Eucalyptus miniata–E. tetrodonta open
forests. We have described in detail the composition and structure as well as
seasonal patterns of leaf area index and above-ground biomass in the
E. miniata–E. tetrodonta open forests of the Gunn
Point region near Darwin in the Northern Territory of Australia. In all, 29
tree species from four phenological guilds were recorded in these forests.
Stand structure suggests that the forests were still recovering from the
impacts of cyclone Tracy and subsequent frequent fires.
Eucalyptus miniata and
E. tetrodonta were significant contributors to
overstorey leaf area index and standing biomass (>70%), and both
leaf area index and biomass were strongly correlated to basal area. Leaf area
index was at a maximum (about 1.0) at the end of the wet season and declined
over the dry season by about 30–40%. There were proportionally
greater changes in the understorey reflecting the greater contribution of
deciduous and semi-deciduous species in this strata. Standing biomass was
about 55 t ha –1 . Detailed descriptions of leaf
area index and biomass are important inputs into the development of a water
and carbon balance for the savanna’s of northern Australia.
Sporophytic self-incompatibility in diploid and tetraploid races of Rutidosis leptorrhynchoides (Asteraceae)
Authors: Young Andrew , Miller Cathy , Gregory Elizabeth , Langston Ann
Published: December 2005

Controlled pollinations were used to examine
the mating system of diploid and tetraploid individuals of the endangered
grassland herb Rutidosis leptorrhynchoides F.Muell.
Crosses among unrelated plants gave 1.5–2 times as many fruit as crosses
between plants that were half-sibs, while selfed crosses generally resulted in
no fruit. Three classes of compatibility reaction were observed within
outcross treatments: (1) reciprocal compatibility, (2) one-way compatibility
and (3) reciprocal incompatibility. This is diagnostic of sporophytic control
of self-incompatibility, which is characteristic of the Asteraceae. This is
supported by the occurrence of a dry stigma and trinucleate pollen. Analysis
of the behaviour of self- and outcross pollen on the stigma by using
fluorescence microscopy shows that rejection of self-pollen does not all occur
at one point but at a number of stages, with cumulative reductions in the
adherence of pollen to the stigma, pollen germination, pollen tube penetration
of the stigma and fertilisation. On the basis of both fruit set and pollen
behaviour data, for any level of relatedness, tetraploid plants are about
20% less likely to be compatible with each other than diploid plants.
This presumably reflects the greater likelihood of matching S alleles given
the greater potential for polymorphism at the individual level. The occurrence
of two plants, one diploid and one tetraploid, that set large amounts of fruit
on selfing shows that self-incompatibility can break down.
Foliar concentrations and resorption of nitrogen and phosphorus in 15 species of eucalypts grown under non-limited water and nutrient availability
Authors: Hawkins B. , Polglase P. J.
Published: December 2005

Mature and senescent foliage were sampled from 15 species of
Eucalyptus, covering three subgenera,
Symphyomyrtus, Monocalyptus and
Corymbia, under non-limiting availability of water and
nutrients (effluent-irrigated plantation). Concentrations of total phosphorus
in mature foliage were relatively high for Eucalyptus
(range 1.6–3.1 mg g–1), inorganic phosphorus
accounting for 60–79% of total phosphorus. Foliar concentrations
of total and inorganic phosphorus in Monocalyptus were
about twice as much as in Symphyomyrtus. Concentrations
of nitrogen did not differ amongst subgenera. About 50% of leaf
nitrogen was resorbed during senescence. In contrast, about
11–24% of phosphorus was resorbed, of which about
48–77% was derived from hydrolysis of organic phosphorus. There
were no significant differences amongst subgenera in resorption of either
nitrogen or phosphorus. Despite significant variability in nutritional
characteristics within subgenera, we conclude that
Monocalyptus has a greater capacity to accumulate foliar
phosphorus (as inorganic phosphorus) than Symphyomyrtus,
but that Symphyomyrtus has a greater phosphorus-use
efficiency (ratio of growth to foliar phosphorus). Foliar inorganic phosphorus
appears to be easily manipulated by nutrient amendment whereas nitrogen is
highly resistant. Resorption efficiency of phosphorus (proportion of total
phosphorus resorbed) is decreased under high availability of soil phosphorus.
Carnivory and nitrogen supply affect the growth of the
bladderwort Utricularia uliginosa
Authors: Jobson Richard W. , Morris E. Charles , Burgin Shelley
Published: December 2005

A glasshouse experiment was designed to determine whether the terrestrial
bladderwort species Utricularia uliginosa Vahl. gained
any growth advantage from carnivory at different levels of nitrogen enrichment
of the substrate. Three organism treatments were used: a control, a
protist-only treatment (Euglena spp.) and a protist
+ meiofauna treatment (Euglena spp. plus nematodes,
copepods, ostracods, cladocerans and Acarina). The organism treatments were
factorially combined with three nitrogen levels (N0, N1, N2). Populations of
Euglena were successfully established in the substrate
of pots in the protist, and meiofauna + protist treatments, and were
found in the traps of plants growing in these treatments. Populations of the
meiofauna from the inoculating cultures were successfully established in the
meiofauna + protist treatment, and were trapped by plants in these
treatments. A background contamination of the control and protist-only
treatments by Acarina occurred over the course of the experiment; however,
numbers of Acarina in these treatments were at least an order of magnitude
lower than numbers of meiofauna in the meiofauna + protist treatment.
Non-acarinid meiofauna were restricted solely to the meiofauna + protist
treatment. Organism treatment interacted significantly with the nitrogen level
of the substrate to affect growth of Utricularia. Plants
trapping Euglena (+ Acarina) had significantly less
dry weight than control plants at the N0 base level of nitrogen; this negative
effect of trapping Euglena on plant growth disappeared
at the two higher nitrogen levels. The dry weight of plants trapping the full
range of meiofauna at the N0 level was comparable with control plants. Plants
trapping the full range of meiofauna + Euglena at
the N1 level had significantly more dry weight than plants trapping
Euglena only, and the highest dry weight of any
treatment; the benefit of trapping the full range of meiofauna +
Euglena was non-significant at the N2 level. Dry weight
of plants was not significantly affected by nitrogen in any organism
treatment. These results suggest that carnivory was overcoming a nitrogen
deficiency induced by Euglena at the N0 level, but was
overcoming deficiencies of other nutrients at the N1 level.
Horticultural development of Australian native edible plants
Authors: Ahmed Amani K. , Johnson Krystyna A.
Published: December 2005

The Australian native edible plant industry is rapidly expanding. We provide a
review of the horticultural research that has been carried out on the top 14
commercially significant Australian native edible plants;
Acacia spp. Miller (wattle),
Acronychia acidula F.Muell. (lemon aspen),
Backhousia citriodora F.Muell. (lemon myrtle),
Eremocitrus glauca (Lindl.) Burkill (desert lime) and
Microcitrus spp. Swingle (native lime),
Hibiscus heterophyllus Vent. and
Hibiscus sabdariffa L. (rosella),
Kunzea pomifera F.Muell. (muntries),
Podocarpus elatus R.Br. ex Endl. (Illawarra plum),
Prostanthera spp. La Billardiere (native mint),
Santalum acuminatum R.Br. (quandong),
Solanum centrale Black (bush tomato),
Syzygium leuhmannii F.Muell. (riberry),
Tasmannia spp. R.Br. (native pepper),
Terminalia ferdinandiana (=
T. latipes Benth. subsp.
psilocarpa Pedley) (kakadu plum) and
Tetragonia tetragonioides (Pallas) Kuntze (warrigal
greens). The research on most of these species has focused on propagation,
breeding, cultivation, nutritional value and the isolation of natural
products. On none of the species has research been completed in all these
areas, and three species have no research published on them. We describe
horticultural research on two other commercial species,
Backhousia anisata Vickery (aniseed myrtle) and
Davidsonia pruriens F.Muell. var.
pruriens and var. jerseyana
(Davidson’s plum), and one species with commercial potential,
Pringlea antiscorbutica R.Br. ex Hook.f. (kerguelen
cabbage). We identify areas that require further research and issues of
concern, such as indigenous intellectual property rights and environmental
implications.
High genetic diversity in the only known population of Aechmea tuitensis (Bromeliaceae)
Authors: Izquierdo Liz Y. , Piñero Daniel
Published: December 2005

Aechmea tuitensis (P. Magaña and E. Lott) is a
narrow endemic species from Mexico. Only one population has been reported. We
studied the genetic variation and structure, and clonal diversity of this rare
bromeliad by using starch gel electrophoresis. Six enzyme systems encoded by
nine gene loci were resolved in nine subpopulations. The percentage of
polymorphic loci was high (77.8%). Mean expected heterozygosity for the
population was 0.12. All loci except CPX-1 were in Hardy–Weinberg
equilibrium. Genetic diversity was substantially larger within subpopulations
(mean Fis = 0.631) than between them
(Fst = 0.196). We detected 33 genetically
distinguishable clones from 109 plants (ramets) sampled. One clone had a
frequency of 32.1%, others showed frequencies ranging from 1.8 to
9.2%, and 19% of the total samples were unique multilocus
genotypes. Aechmea tuitensis exhibits high genetic
diversity even though it has an extremely narrow distribution. Our results
also suggest that the effect of genetic drift on genetic structure in
A. tuitensis might be counteracted by the influence of
vegetative reproduction.
Water relations of feral olive trees (Olea europaea) resprouting after severe pruning
Authors: Shelden Megan , Sinclair Russell
Published: December 2005

Water relations of feral olives (Olea europaea L.) were
studied on a location in the Mt Lofty Ranges, South Australia. In spring
(October–November), 6 months before the study commenced, an area of
trees had been cut back to stumps as part of an eradication project. The
stumps resprouted vigorously over summer, similarly to regrowth seen following
wildfire. The following autumn and winter, plant water potentials and soil
matric potentials were measured on the cut trees and adjacent control trees,
to determine whether the cut trees were better hydrated due to the pruning
treatment. In autumn, before the winter rains began, the resprouting trees
were more hydrated than the control trees, with a difference in predawn water
potentials of between 2 and 4 MPa, and 1.5 MPa or greater throughout the day.
The soil matric potential was much less negative on the cleared site, both at
the surface and at 50-cm depth, indicating that soil water had been less
depleted by the cut trees than by the intact trees. This improved hydration
was similar to that reported for sclerophyll vegetation after defoliation by
fire. Results have some significance for feral olive eradication projects.
Accumulation of proline analogues and adaptation of Melaleuca species to diverse environments in Australia
Authors: Naidu Bodapati P. , Paleg Leslie G. , Jones Graham P.
Published: December 2005

The genus Melaleuca is native to Australia, with about
250 species spread from favourable to very stressful ecological habitats. We
analysed the leaves of 125 Melaleuca species for the
accumulation of proline analogues to explore relationships between the ability
of the species to accumulate proline analogues and their ability to adapt to
various stressful habitats in Australia. Melaleuca
species that have evolved the ability to accumulate only L-proline seem to be
adapted to non-saline or non-sodic soils in regions of higher rainfall.
Species that accumulate N-methyl-L-proline seem to be
adapted to saline and/or sodic soils with moderate amount of rainfall.
Species that accumulate
trans-4-hydroxy-N-methyl-L-proline
seem to be adapted to saline and/or sodic soils and occur in areas with
considerably lower rainfall, while species that accumulate
trans-4-hydroxy-N,N-dimethyl-L-proline
are widely distributed in Australia, with a particular adaptation to extremely
arid (deserts) and saline and/or sodic soils. The species accumulating
more than one osmoprotectant seem to have an ecophysiological advantage over
plants accumulating only one osmoprotectant.
Efficient organogenesis of an Australian passionfruit hybrid (Passiflora edulis x Passiflora edulis var. flavicarpa) suitable for gene delivery
Authors: Hall Rhonda M. , Drew Roderick A. , Higgins Colleen M. , Dietzgen Ralf G.
Published: December 2005

An efficient regeneration protocol based on
organogenesis from cotyledon explants and suitable for gene delivery has been
developed for an Australian passionfruit hybrid. Multiple shoots were
regenerated from 30-day-old cotyledon explants on Murashige and Skoog (MS)
medium containing 6-benzylvaminopurine (BAP) and coconut water. Media pulsing
experiments were conducted to investigate the effect on organogenesis of
exposure time of the explants to MS containing 10 _M BAP and 10%
(v/v) coconut water, i.e. passionfruit regeneration medium (PRM).
Continuous exposure of these explants to PRM maximised the number of shoots
produced to 12.1 per explant. However, periods on hormone-free medium improved
the appearance of the shoots and increased the number of explants with shoots
from 75 to 84.6%. Further, shoots exposed for 7 days to half-strength
MS supplemented with 10 mM NAA (1-napthalene acetic acid) produced twice as
many plantlets than those on half-strength MS alone. Transient GUS
histochemical assays indicated delivery of the uidA gene
via Agrobacterium tumefaciens.
The Inflorescences of the Australian Genera Diplolaena R.Br and Chorilaena Endl (Rutaceae)
Authors: Classenbockhoff R , Armstrong JA , Ohligschlager M
Published: December 2005

The inflorescences of five Diplolaena species and of Chorilaena quercifolia were analysed morphologically. Both genera form aggregated, campanulate inflorescences; in Diplolaena they are terminal, standing at the end of leafy shoots, while in Chorilaena they are axillary but with no vegetative 'Unterbau'. As to their position, the inflorescence of Diplolaena is homologous to the whole panicle whereas the inflorescence of Chorilaena is homologous to a branch of it. This study suggests that the basic type of inflorescence in Australian Rutaceae is a determinate panicle which is reduced to few-flowered inflorescences in some species. In both Chorilaena and Diplolaena each flower has a subtending bract and up to two prophylls. In Diplolaena, the showy outer bracts always bear flowers or lateral branches of the inflorescence of first branch order. The inner bracts may be sterile prophylls, indicating a reduction of flowers, or are fertile, subtending flowers of a higher branch order. Thus, the head-like inflorescence of Diplolaena is a reduced panicle. It differs from the inflorescence of Chorileana in the further aggregation of flowers and in the modification of bracts including their enlargement and arrangement into a pseudocorolla; in some taxa (e.g. D. grandiflora) the pseudocorolla is brightly coloured. The two genera have derived inflorescences that have evolved via divergent lines of modification.
Development of the Stomatal Complexes During Ontogeny in Eucalyptus and Angophora (Myrtaceae)
Authors: Carr DJ , Carr SGM
Published: December 2005

The mode of stomatal development is studied in cotyledons, seedling and adult leaves of species of eucalypts and three species of Angophora. In the cotyledons of all species examined the early stomatal initials are unilabrate or dolabrate. The stomatal initials in seedling leaves of species of the Corymbosae and Clavigerae are anisocytic. In the 4th seedling leaf in species of a group we have previously called Monocalyptus the stomatal initials are also anisocytic. All other eucalypts retain the early cotyledonary mode of origin of stomata throughout life. These two modes of origin, whether anisocytic or by unilabrate and dolabrate initials, are set in all eucalypts from the 4th seedling leaf onward. Secondary characteristics of the adult stomata, e.g. number of subsidiary cells, are more complex than those of the seedling leaves; rarely, the relatively simple pattern of the seedling leaves may persist in the adult leaves of a given species. In species in which the initials in adult leaves are unilabrate or dolabrate, groups of stomata may share one or more subsidiary cells or be juxtaposed without an intervening subsidiary cell. The sister cell(s) of the guard mother cell may precociously develop a thicker cuticle than ordinary epidermal cells, and this may be apparent at maturity. The abaxial stomata of the cotyledons (but not of seedling or adult leaves) are regularly aligned parallel to the main venation. The existence of three main types of origin of stomata characteristic of three large non-interbreeding groups of eucalypts is of interest in the taxonomy of the genus.
Detection of DsRNA Viruses in Isolates of Australian Smut Fungi and Their Serological Relationship to Viruses Found in Ustilago maydis From the U.S.A.
Authors: Francki MG , Kirby GC
Published: December 2005

DsRNA was detected in two killer strains of smut fungi collected in Australia. This was determined by digestion of dsRNA preparations with RNase in the presence of high and low salt concentrations and detection of the nucleic acid using agarose gel electrophoresis. Isometric particles approximately 40 nm in diameter were detected using electron microscopy in the same isolates. These particles were shown to be serologically related but not identical to the P1 Ustilago maydis. virus-like particle (VLP) as determined by immunodiffusion using an antiserum to the P1 VLP. This shows that VLPs similar to those in North America also occur in Australia. Neither isometric particles nor dsRNA were detected in three other killer strains of smut fungi or in 11 sensitive strains. This indicates that there is a lack of correlation between killer activity and the presence of a dsRNA VLP in some Australian isolates of smut fungi.
A Scanning and Transmission Electron Microscope Study of Leaf Axil Structure in Araucaria cunninghamii
Authors: Burrows GE
Published: December 2005

The cells of active plant meristems are characterised by their small size, thin walls and a full complement of organelles, most noticeably a large nucleus surrounded by densely staining, little-vacuolated cytoplasm. The axillary meristems of Araucaria cunninghamii Aiton ex D. Don (hoop pine) possess a similar ultrastructure, even though they quickly assume a near complete, potentially permanent quiescence following their detachment from the flanks of the actively dividing apical meristem. However, they differ from metabolically active cells in that those organelles and structures associated with cytokinesis and cell wall formation are either absent (microtubules) or infrequent and in an apparently inactive state (smooth endoplasmic reticulum, non-vesiculating dictyosomes, nuclei with a low heterochromatin to euchromatin ratio). In addition, storage products (starch, lipid globules), usually not present in metabolically active cells, are well developed. In addition to not developing a bud-like organisation, the meristems are also unlike typical axillary buds in that they have no vascular or provascular connections with the axial vascular tissues and are bounded adaxially by a group of thick-walled cells. While these cells constitute a physical barrier around the axillary meristems, they are nucleated and possess numerous simple pits that have a high plasmodesmatal frequency. Thus it appears that the meristems are not physiologically isolated, but are in cytoplasmic continuity with the remainder of the plant.
Buoyancy of Avicennia marina Propagules in South-Eastern Australia
Authors: Clarke PJ , Myerscough PJ
Published: December 2005

Buoyancy of propagules of Avicennia marina (Forsk.) Vierh. was observed in the laboratory and in the field. Under constant exposure to seawater in the laboratory, propagules that shed their pericarp sank while those that retained their pericarp floated. The time taken for propagules to shed their pericarps varied greatly between trees in a population and between populations. However, more propagules lost their pericarps and sank faster in 10% seawater than in full seawater. Propagules that had sunk in 10% seawater refloated after several days' immersion. In the field, propagules placed at three tidal levels and exposed to differing periods of tidal inundation all lost their pericarps and sank within 24 h with no differences detected between tidal levels. Field observations were also made where brackish and seawater sites could be compared. Propagules shed their pericarps faster and sank earlier at the brackish site, although after 24 h more than 80% of propagules had sunk at all sites. After 48 h propagules in the brackish site began to refloat. These observations suggest that most A. marina. propagules strand and establish near the parent tree populations and only a few are dispersed more widely.
The Effects of Burning and Simulated Grazing on Productivity, Forage Quality, Mortality and Flowering of Eight Subalpine Herbs in Kosciusko National Park.
Authors: Leigh JH , Wood DH , Slee AV , Holgate MD
Published: December 2005

The effects of simulated grazing and burning on biomass production, forage quality (CP and DM digestibility), plant mortality and flowering of 4 native perennial grasses (Poa phillipsiana, P. sieberana, Danthonia pilosa and Festuca asperula) and four perennial forbs (Aciphylla simplicifolia, Arthropodium milleflorum, Bulbine bulbosa and Hypochoeris radicata) growing in Kosciusko National Park were studied over a 16-month period. Cutting at 8-week intervals reduced the amount of regrowth at successive harvests as well as the survival of individuals. The season in which a single cut was made generally had a greater effect on the amount of regrowth than length of the regrowth period. Burning promoted flowering and improved the forage quality of the grasses. Rabbits bred only when they were able to obtain forage with a minimum protein content of 14%, provided mainly by the forb species. The management implications resulting from the interaction of fire and grazing, particularly by rabbits and domestic stock, for ecosystem quality are discussed.
Comparative Development of Some Taxonomically Critical Floral Inflorescence Features in Cyperaceae
Authors: Bruhl JJ
Published: December 2005

Morphology at different developmental stages was investigated by dissection and by scanning electron microscopy (SEM) in five sedges: Eleocharis (three species) and Schoenoplectus (both Cyperoideae, Scirpeae), and Lepidosperma (Caricoideae, Schoeneae). In each case all the perianth segments (scales or bristles) were positioned outside the staminal primordia or stamens, consistent with classical interpretations of flowers. Putative exceptions and previous alternative interpretations of floral morphology in the Cyperaceae are discussed. SEM developmental studies of Hypolytreae (e.g. Scirpodendron) are needed for further clarification of interpretative floral/inflorescence morphology in the family.
Stamen and Seed Cuticle Morphology in Some Arthropodium and Dichopogon Species (Anthericaceae)
Authors: Stringer S , Conran JG
Published: December 2005

A study involving androecial and seed cuticular morphology under scanning electron microscopy for seven Arthropodium and four Dichopogon species showed that the androecial characters traditionally used to separate the genera form a morphological continuum. Similarly, the seed cuticles showed intergradation of form between the two genera. The reduction of Dichopogon to synonymy under Arthropodium as previously advocated by some authors is supported.
Needle Cast of Pinus radiata in New South Wales
Authors: Choi D , Simpson JA
Published: December 2005

Green needles of 7-9-year-old Pinus radiata trees at a plantation in Sunny Corner, New South Wales, have been infected primarily by two species of fungi, Cyclaneusma minus and Lophodermium pinastri. Needles emerged from fascicle sheaths in October and November and persisted on the trees for about 2 years before developing symptoms of Cyclaneusma minus infection during summer and autumn. Immature current year's needles were infected by both C. minus and L. pinastri before they were fully elongated. Ascospores of C. minus were released from cast needles in very large numbers in spring (September-November) and most new infections occurred during this period. Infection by L. pinastri lagged behind that by C. minus by about 2 months. There was significant between-tree variation in disease levels of each of these fungi. Susceptibility to C. minus was not linked with susceptibility to L. pinastri. Nitrogen levels in P. radiata foliage and symptom expression are correlated.
Suppression of Phytophthora Root Rot by a Composted Eucalyptus Bark Mix.
Authors: Hardy GESJ , Sivasithamparam K
Published: December 2005

A potting medium containing composted Eucalyptus (Eucalyptus calophylla and E. diversicolor) barks
(CEB) was suppressive in decreasing order to Phytophthora cryptogea, P. nicotianae var. nicotianae, P.
citricola, P. drechsleri and P. cinnamomi infections of waratah (Telopea speciosissima) and Banksia
occidentalis. Suppressiveness of the CEB appears to be biological, as the CEB became conducive to root
rot after steam-sterilisation. A non-composted commercial mix (nurseryman's mix, NM) was conducive
to all the Phytophthora spp. tested.
Pathogenicity of each Phytophthora sp. varied between the container media. In the NM, P. citricola
was the most pathogenic species. Steaming the NM resulted in pathogenicity being similar for all
Phytophthora spp. However, this did not happen when the CEB was steamed.
Characterisation of Strains of Fusarium oxysporum f.sp. cubense by Production of Volatiles
Authors: Moore NY , Hargreaves PA , Pegg KG , Irwin JAG
Published: December 2005

The production of volatiles on steamed rice by Australian isolates of Fusarium oxysporum f. sp. cubense
correlated well with race and vegetative compatibility group (VCG). All race 4 isolates (VCGs 0120,
0129) produced distinctive volatile odours which gave characteristic gas chromatograms where the num-
ber of peaks equated to VCG. Race 1 (VCGs 0124, 0125) and race 2 (VCG 0128) isolates, as well as
non-pathogenic isolates of F. oxysporum from the banana rhizosphere, did not produce detectable
volatiles and gave chromatograms without significant peaks.
Floral Biology and Inefficient Pollen Removal in Banksia spinulosa var neoanglica (Proteaceae)
Authors: Vaughton G , Ramsey M
Published: December 2005

Stigma receptivity, pollen longevity and rates of flower opening were examined in Banksia spinulosa var. neoanglica. The interaction between these aspects of floral biology and removal of self pollen by floral visitors, autogamous pollen deposition and autogamous fruit set was determined. Flowers were strongly protandrous; most stigmatic grooves opened and maximum stigma receptivity occurred 3-4 days after the flowers opened. Over 80% of pollen was viable when flowers first opened. Pollen longevity was extended; 58% and 33% of pollen was still viable 8 and 12 days respectively after the flowers opened. Rates of flower opening were slow with only 19-32 flowers opening per day, depending on temperature. More than 80% of flowers had self pollen remaining on their pollen presenters 5 days after the flowers opened. Autogamous pollination did not occur until at least 6 days after the flowers opened. Pollen deposition and fruit production were significantly less on autogamous than open-pollinated inflorescences. Pronounced protandry, extended pollen longevity and slow rates of flower opening in B. spinulosa may have been selectively favoured by inefficient removal of self pollen by floral visitors.
Micropropagation of Juvenile Eucalyptus regnans (Mountain Ash)
Authors: Blomstedt C , Cameron J , Whiteman P , Chandler SF
Published: December 2005

Node-derived shoot cultures of Eucalyptus regnans were established from in vitro grown seedlings on Murashige and Skoog basal medium supplemented with 0.5 mg L-1 (2 μm) zeatin and 0.05 mg L-1 (0.3 μm) napthaleneacetic acid. A double sterilisation method was essential to obtain clean material from seed. Microcuttings from established cultures were used to develop an efficient method for in vitro rooting. Rooting was best after a 7 day pulse on 20 mg L-1 (98 μm) indolebutyric acid. Hoagland's or Woody Plant Medium supported better rooting than MS basal medium and rooting was significantly enhanced by subculture to activated charcoal after the auxin pulse. Carbohydrate (sucrose or glucose) was essential for rooting while high light intensity was inhibitory. Optimal light conditions were a 12 h day (17 W m-2). In all, 90% of plantlets established in the nursery survived the winter.
Fruit Clustering in the Myrtaceae: Seed Survival in Capsules Subjected to Experimental Heating.
Authors: Judd TS , Ashton DH
Published: December 2005

The effect of the natural clustering of capsules on seed insulation was investigated by heating mature
capsules of Kunzea ambigua in a muffle furnace at 250°C for up to 5 min. Survival of the encapsulated
seed of K. ambigua was higher when capsules were retained in their natural aggregates than when
individual fruits were heated. Seed within clustered K. ambigua fruits also survived heating for longer
periods than in individual capsules of both Leptospermum laevigatum and Eucalyptus regnans, species
which depend heavily on encapsulated seed for post-fire regeneration. The clustered arrangement of
sessile K. ambigua capsules reduces exposure to external heat sources by protecting the base and sides
of the capsule. Given that any delay in heat penetration may be critical to seed survival, fruit clustering
could be an important adaptation to fire by K. ambigua and other similar small-fruited Myrtaceae.
The limited survival times of seed within individual capsules of the three species tested support
evidence that survival of encapsulated seed during fire is largely possible due to brief flame residence
times in individual shrub and tree canopies.
Floral Biology and Reproductive Phenology of Avicennia marina in South-Eastern Australia
Authors: Clarke PJ , Myerscough PJ
Published: December 2005

Flowering, pollination and reproductive phenology of the tree, Avicennia marina (Grey mangrove), were examined on the south-east coast of Australia in New South Wales. Individual flowers are protandrous and open for 2-5 days, while a flower cluster has open flowers for 2-4 weeks. About 16000 pollen grains and four ovules are produced per flower. Self-pollination of an individual flower is unlikely because of protandry, but the sequence and synchrony of flowering, together with pollinator behaviour, favour geitonogamy. Some fruit is set when cross-pollination is restricted by bagging flowers, which indicates partial self-compatibility. Subsequently, fruit abortion is higher in the bagged treatment than in those open-pollinated; this may reflect some pre-dispersal inbreeding depression. Between 4 and 41% of open-pollinated flower buds set fruit, most of which had one or rarely two seeds. Phenologically, each reproductive stage is unimodal and the whole process from bud initiation to abscission of mature fruit is completed within a year. Initiation of floral buds, flowering, growth and abscission of fruits are almost synchronous among fecund trees at a particular latitude each year. Latitudinal differences occur consistently among populations that are separated by less than 2° of latitude; those at lower latitudes flower earlier. Flowering of individual trees varies greatly between years and many trees fail to reproduce each year, although the populations remain fecund from year to year. A flexible breeding system and regular population fecundity ensure annual propagule supply in the populations studied.
Late Pleistocene Vegetation and Climate Near Melaleuca Inlet, South-Western Tasmania
Authors: Jordan GJ , Carpenter RJ , Hill RS
Published: December 2005

Macrofossils of 27 taxa and microfossils of 47 taxa are identified from a Late Pleistocene deposit at Melaleuca Inlet with a minimum age of 38 800 years. Interpretation of the fossil assemblage suggests that at the time of deposition the climate was cooler than at present and at least as wet. The local vegetation was dominated by wet scrub and sedgeland-heath communities with rainforest and wet sclerophyll forest also present. Species composition was similar to extant vegetation in the region but now-extinct species and possibly communities were present. Charcoal occurs in the sediments and the taxonomic make-up of the assemblage is consistent with the presence of a well established high fire frequency, despite the deposit pre-dating the earliest known human occupation of Tasmania.
The Role of Fire in Establishment of Seedlings of Serotinous Species From the Sydney Region
Authors: Bradstock RA
Published: December 2005

Observations and experiments were performed to examine the relationship between fire and seedling establishment in the following serotinous/woody species: Banksia ericifolia L.f., Banksia serrata L.f., Petrophile pulchella (Schrad.) R. Br. and Isopogon anemonifolius (Salisb.) Knight. For all species a moderate-intensity fire had no effect on the viability of seeds stored in cones compared to seeds stored in unburnt cones. Germinated seeds of all species, placed in meshed and unmeshed enclosures within an unburnt area, were consumed extensively by an unknown predator within 2 months of placement. No such effect occurred in similar treatments within a recently burnt area. Heating of the soil surface and the nature of substrates (litter, ash, bare soil) had variable effects on seedling establishment. Establishment of B. ericifolia and B. serrata was unaffected by the treatments whereas in P. pulchella and I. anemonifolius substrates and heating had significant effects. In P. pulchella establishment was significantly reduced on litter compared with pure ash. In I. Anemonifolius establishment was significantly higher on treatments with litter or mixed ash, except on soils that had received the low heat treatment, where there was no significant substrate effect. It was concluded that fire could create a more favourable soil-surface environment for establishment in P. pulchella only. In the other species, fire would have no effect or, in I. Anemonifolius, establishment might be enhanced in unburnt conditions. This conclusion does not take into account the effects of cover (overstorey and understorey) on establishment. It was concluded that predation of newly germinated seedlings may be the most important restriction on seedling establishment in unburnt populations.
Mycorrhizal Associations of Plant-Species in Hawkesbury Sandstone Vegetation
Authors: Bellgard SE
Published: December 2005

The mycorrhizal associations of plant species in an open woodland and heathland on Hawkesbury Sandstone soils were examined. The two geographically disjunct sites supported vegetation of differing physiognomy, but possessed many species common to both sites. At the woodland site, 21 of the 32 plant species examined had mycorrhizal associations. At the heath site, 31 of the 47 plant species examined were mycorrhizal. Mycorrhizal associations were found on representatives of the Cyperaceae and Proteaceae, families not previously thought to be mycorrhizal. Internal hyphae, vesicles, and cortical hyphal coils were discovered on the roots of two species of Cyperaceae and on the non-proteoid roots of nine species of the Proteacae. Several species within genera and families previously known to be mycorrhizal were also found for the first time to have associations. Endomycorrhizal associations predominated at both sites, but several species had both ecto- and endomycorrhizal associations. The presence or absence of mycorrhizal associations was consistent on the roots of those plant species common to both sites examined.
Breeding System and Pollination Levels of Banksia ericifolia
Authors: Goldingay RL , Schibeci SM , Walker BA
Published: December 2005

Experiments were carefully designed to determine the breeding system of Banksia ericifolia L.f. An equivalent percentage of flowers (78%) contained pollen tubes following self-pollination and open-pollination while a significantly smaller percentage of flowers in an autogamy treatment (44%) and cross-pollination treatment (55%) contained pollen tubes. Significantly more of the inflorescences in the open-pollination (60%) and cross-pollination (33%) treatments produced fruit compared with those in the self-pollination (11%) and autogamy treatments (13%). We suggest that B. ericifolia is largely self-incompatible because fruit production did not reflect pollen tube abundances. The influence of pollination levels on fruit production was determined by reducing the number of flowers on an inflorescence to 100 (i.e. 10% of original) or fewer and hand-pollinating these with cross pollen. There was no difference in fruit production between inflorescences with reduced flower number and open-pollinated inflorescences which had their full complement of flowers. Thus, the ability of an inflorescence to produce fruit appears more likely to be determined by the type of pollen received (cross versus self) rather than by the number of pollinated flowers it contains.