bluuebunny/crossref_metadata_2025 huggingface dataset:
Problems of placing boundaries on ecological continua - options for a workable national rainforest definition in Australia
Authors: Lynch A. J. J. , Neldner V. J.
Published: December 2005

Options for a new definition of, and key for, rainforest in Australia are
provided. The definitions take a national perspective, and are based on the
ecological characteristics of rainforest species and some structural and
floristic characteristics. Rainforest plant species are defined as those
adapted to regenerating under low-light conditions experienced under the
closed canopy or in localised gaps caused by recurring disturbances which are
part of the natural rainforest ecosystem, and are not dependent on fire for
successful regeneration. Three definitions are provided which differ in the
extent of inclusion of transitional and seral communities. The first
definition recognises communities such as mixed forests as transitional to
rainforests and therefore as separate communities. The second definition
includes a minimal component of emergent non-rainforest species in rainforest
in the recognition that the main floristic component and functioning of the
communities cannot be distinguished. The third definition includes the late
successional stages of transitional and seral communities in rainforest on the
presumption that such communities include non-rainforest species which are
close to senescence, and that these communities are essential for the
long-term conservation of rainforest in areas where rainforest is vulnerable
and subject to major disturbance, particularly by fire. The first definition
is concluded to be the least ambiguous and arbitrary, and enables a consistent
approach to rainforest management. Recognition of mixed forests as a
distinctive and mappable vegetation type should be incorporated in a
comprehensive conservation strategy inclusive of all ecosystem developmental
stages.
Phomopsis castanea, a Seed-borne Endophyte in Chestnut Trees
Authors: Washington W. S. , Hood V. , Stewart-Wade S.
Published: December 2005

Phomopsis castanea(Sacc.) Höhn was found to occur
endophytically in plant parts of European chestnut including flowers, leaves,
shoots and fruits, when apparently healthy trees of four cultivars were
sampled seven times throughout 1 year. This fungus is associated with the
important post-harvest disease Phomopsis nut rot. The fungus was also shown to
be endophytic in seedlings of the cultivar Perton’s Pride, and seed
transmitted. There were apparent differences in the incidence of
P. castanea isolated between the four cultivars and the
two sites tested. The incidence of plant parts yielding
P. castanea was highest for cultivar Marone at both
sites, and lower for cultivars Sword, Buffalo Queen and Lucente. The plant
parts with the highest incidence of P. castanea were the
burr, the male flower, the stigma and style, and 1-year-old and 2-year-old
shoots; those with the lowest incidence were the 3-year-old and 4-year-old
xylem, the inner peduncle and the nut kernel. There were no apparent trends in
the incidence of the fungus recovered from plant parts at different times of
the year.
Charophyte Flora of South-eastern South Australia and South-western Victoria, Australia: Systematics, Distribution and Ecology
Authors: García Adriana
Published: December 2005

The charophytes (Charales, Charophyta) from south-eastern South Australia and
south-western Victoria were studied on the basis of collections from 56
waterbodies, 39 of which included charophytes.
Chara globularis var. globularis
(Thuillier) Wood, C. globularis var.
virgata (KÜtzing) Wood,
C. fibrosa var. fibrosa (Agardh ex
Bruzelius) Wood, C. fibrosa var.
acanthopitys (Braun) Wood,
C. hookeri Braun, C. preissii
(Braun) Wood, Lamprothamnium macropogon (Braun) Ophel,
Nitella ignescens García,
N. ungula García,
N. lhotzkyi (Braun) Braun, N. aff.
lhotzkyi, and N. congesta (Brown)
Braun were recognised. An identification key for these species makes
determination possible. A brief characterisation of the environment where the
charophytes were found is provided, as a first approximation of the ecological
requirements of Australian charophytes. At this stage their distribution can
be mainly related to salinity, with charophytes living in fresh to hypersaline
conditions (0.0–58.0 g L–1). Special
attention is put on L. macropogon, a euryhaline
calcifying species, which has the broadest distribution in the area.
The floristic analysis shows endemism, dioecism and a high diversification of
non-calcifying taxa as the main characteristics of the charophyte flora
analysed.
Charophyte Occurrence, Seed Banks and Establishment in Farm Dams in New South Wales
Authors: Casanova Michelle T. , Brock Margaret A.
Published: December 2005

Farm dams are an important and common water resource in rural Australia. They
provide relatively permanent surface water for stock and wildlife. They
typically have high turbidity and high levels of disturbance by stock. The
occurrence of charophytes in these water bodies was examined, as well as the
conditions under which they germinated and established. Charophytes were found
in 15% of 65 farm dams surveyed in two regions in New South Wales,
Australia. However, charophytes germinated from 64.5% of farm dam seed
banks sampled (n = 17). Species found were
Chara australis R.Br., C. fibrosa
Agardh ex Bruzelius, C. globularis Thuillier,
C. muelleri A.Br.,
Nitella cristata A.Br. and
N. tasmanica A.Br. Farm dams in which charophytes were
found both in the survey and in the seed bank had lower turbidity, lower
dissolved phosphorus levels and more extensive submerged plant communities
than average. Charophytes established from the seed banks under experimentally
induced water regimes when high water clarity was maintained and the
disturbance of stock grazing was removed. Farm dams can support populations of
perennial and annual charophyte species, and provide a habitat that is less
available in naturally occurring shallow water bodies of the regions.
Contributions to the Biology of Mulga. II. Germination
Authors: Preece PB
Published: December 2005

Investigations into the germination behaviour of seed of the widespread Australian
arid zone leguminous tree Acacia aneura Benth. are described. Hardseededness has
been overcome in routine laboratory studies, but attempts to understand the mechanism
by which it is overcome in nature were unsuccessful. The seed germinates equally well
in the dark and in the light within the temperature range 15-36°C. Temperatures
between 20 and 30° are optimal for germination, and carbon dioxide concentrations
up to 5 % increase the germination rate above that displayed in ambient air. A simple
model has been developed which suggests that seed of this species should have been
available and should have germinated in c. one year in every nine, since records began
in parts of western New South Wales where mulga regeneration is absent.
Vascular differentiation in the wheat embryo
Authors: Swift JG , O'Brien TP
Published: December 2005

The sequence of vascular differentiation in the scutellum, coleoptile, and firbt foliage leaf of the wheat embryo is traced by examining serial sections of these organs at selected intervals after the initial soaking of the grain. Mature sieve elements are found first in the scutellum 3-6 hr after soaking, in the midrib of the first leaf after 6 hr, and in the coleoptile after 18 hr. In all three organs xylem differentation lags behind that of the phloem; mature tracheary elements are present in the scutellum by 18 hr, in the midrib by 24 hr, and in the coleoptile by 30 hr. It is suggested that there are four loci of sieve element differentiation and two loci of tracheary element differentiation. These observations are discussed with reference to previous accounts of vascular differentiation.
Male flowers in Eucalypts
Authors: Carr SGM , Carr DJ , Ross FL
Published: December 2005

Eucalyptus calophylla and other species of series Corymbosae are shown to
produce functionally male flowers by abortion of the structures of the ovary during
development. In their extreme form male flowers may be recognized by their shape
but others outwardly resemble bisexual flowers. In E. calophylla some male flowers give
rise to fruits which are aberrant in shape and seedless. The ratio of male to bisexual
flowers varies from tree to tree. Some trees appear to produce only male flowers. The
morphology and anatomy of male and bisexual flowers are described and compared.
The oil duct systems of male flowers are not fully developed.
The evident trend towards polygamy in some species of series Corymbosae (and
in E. calophylla towards androdioecism) raises the question of its adaptive and
evolutionary significance.
Effect of nitrogen source on growith of Eucalypts in sand culture
Authors: Moore cWE , Keraitis K
Published: December 2005

Twelve species of Eucalyptus were grown in sand culture to determine their
response to nitrate and ammonium nitrogen, and to different proportions of the two
ions. Response was measured in terms of plant height, yields of plant parts (stems,
branches, leaves, and roots), and number of branches.
The results indicate a wide variation in the response of different species to form
of nitrogen. A classification of species in terms of their overall response bears no
relation to the accepted taxonomic classification. On the basis of the results for the 12
species, it appears that plants of similar ecological habitat tend to have similar responses.
Thus, typical woodland species (E. melliodora, E. blakelyi, and E. albens) behave quite
differently from typical forest species (E. rossii and E. sideroxylon). Nevertheless,
there are differences within such general groupings; e.g. forest species such as E.
Agglomerata and E. macrorhyncha form a distinct group, apparently unrelated to the
other forest species tested. The response of E. polyanthemos, which occurs in both dry
sclerophyll forests and woodlands, is similar to that of the typical forest species.
When Eucalyptus species are to be grown in sand culture for nutrition or other
trials, a preliminary test is necessary to determine the preferred form of nitrogen for
each species. Otherwise the effects of the factor being tested may be so masked as to
render the test valueless.
An analysis of Atriplex inflata populations from western New South Wales
Authors: Malik RA , Anderson DJ
Published: December 2005

Pattern analyses of density and performance data collected from separate
populations of Atriplex inflata in the western Riverine Plain of New South Wales
consistentiy indicated two linear scales of contagion at 2-4 and 16 m. The largerscale
plant pattern corresponds to a similar pattern of microtopographical variation
but regressions of density alone on microtopography are significant, indicating
possible alternative mechanisms for establishment (as indicated by density data)
and subsequent performance (as indicated by cover data).
The performance of A. inflata plants has been assessed experimentally on a
range of natural soils and in controlled nutrient solution culture. The results suggest
that performance (as estimated by dry weight yield) is significantly affected by soil
type, water stress, and a soil type ° water stress interaction. The prime effect of soil
variation on yield appears to be mediated by variation in soil cation balance.
Variation in leaf characteristics among provenances of Eucalyptus camaldulensis Dehn. grown in Zambia
Authors: Burley J , Wood PJ , Hans AS
Published: December 2005

Eight morphological characters of leaves were examined in 2-year-old trees of 25 provenances of Eucalyptus camaldulensis Dehn, grown in a replicated trial in Zambia. Provenances differed significantly in leaf length and width, base angle, and oil gland density but significant effects were attributed to trees within provenances. Leaf curvature also varied between provenances, trees, and branches. The tip angle and the number of veins did not vary significantly. Leaf length and oil gland density were related to maximum temperature at seed source rather than to latitude but the reverse occurred for leaf width. Significant amounts of variation were explained by a linear combination of temperature and latitude but not by longitude, altitude, or rainfall. Information on seven traits was combined in principal component analysis in which the first component (a measure of leaf shape) accounted for 36% of total observed variation while the second (weighted largely on leaf length) accounted for 26%. Mapping of both univariate and multivariate results indicated that there are two major ecotypes and gave some evidence of clinal and ecotypic variation within them. The conclusions support those of other workers both in natural populations in Australia and in exotic populations elsewhere.
Mechanisms Underlying the Decline and Recovery of a Characean Community in Fluctuating Light in a Large Oligotrophic Lake
Authors: Hawes Ian , Howard-Williams Clive , Schwarz Anne-Maree
Published: December 2005

Between July 1993 and September 1994 Lake Coleridge, an oligotrophic New
Zealand lake, underwent a period of abnormally low water clarity. Over this
time, characean algal biomass in the littoral zone of the lake underwent a
dramatic decline. Restoration of the lake’s normal high clarity followed
and over the next 2 years there was a recovery of the community to close to
pre-decline levels. Experimental and field studies investigated the mechanisms
underlying the decline and recovery. The response of
Chara corallina Willd. was investigated in detail. This
plant responded to exposure to light below the instantaneous compensation
point for photosynthesis by reducing rates of photosynthesis and respiration
and depletion of storage products. This eventually led to the decay of the
basal cells and detachment of plants from the sediment. In the lake, they were
subsequently washed out of the littoral zone by wind-generated currents. When
C. corallina, acclimated to below-compensating light
levels, was returned to favourable light conditions in the laboratory, these
trends were reversed. However, once biomass had been lost in the lake,
recovery required growth of new plants. The most important methods of
regeneration were by down-slope invasion and regrowth of buried shoots.
Ecotypic variation in Eucalyptus viminalis Labill. I. Leaf surface waxes, a temperature × origin interaction
Authors: Banks JCG , Whitecross MI
Published: December 2005

Electron microscopic evidence is presented to show that leaf surface waxes
from three ecotypes of Eucalyptus viminalis Labill. react differently to temperature.
Density of wax rodlet coverage on juvenile leaves declined markedly over the temperature
range 18-33°C for two of the ecotypes while the third showed only a gradual
decline. A differential response to temperature was also noted with regard to wax
rodlet morphology. Possible explanations for ecotypic differences are discussed.
Chara braunii (Charales, Charophyta) in an Arid Rainfed Waterbody, Saudi Arabia
Authors: Hussain M. I. , Khoja T. M.
Published: December 2005

An account is given of a typical rainfed waterbody in the Al-Ammariyah Wadi
(Saudi Arabia), with special reference to charophyte vegetation, water
chemistry and topography of the area, which was studied from April 1996 to
July 1997. Recurring patterns following rainfall and inundation of the
waterbody are described as a model of temporal succession of biotic
communities. Unispecific Chara braunii Gm. meadows were
the first aquatic vegetation to emerge and overwhelmingly dominated the
freshwater lentic ecosystem. This was followed by plankton and desert plants
as the waterbody dried out. Chara braunii is reported as
a new record for the Saudi Arabian charoflora. The species is characterised as
stenohaline and tends to grow in vivo and
in vitro in the salinity range of 0.2–0.8‰.
A gradual increase in elements and ions (Si 20–31 mg
L–1 and pH 6.8–7.6) in the water was
demonstrated as the waterbody desiccated. As a result of the increasing
concentration of ions and pH, C. braunii developed heavy
encrustation, and hastened fructification prior to desiccation of the
waterbody between June and July 1997. Survival and emergence of
C. braunii is positively correlated with drought
resistant-oospores, specificity to hyposalinity, water-level fluctuations, and
absence of herbivores.
Vascular System of the Stem of the Wheat Plant .II. Development
Authors: Patrick JW
Published: December 2005

The sequence of vascular differentiation in the shoot of the main tiller of Triticum
aestivum L. was reconstructed from seriai transverse sections of shoot apices made at
various stages of development. The pattern of initiation and development of the pro-
cambial strands was confirmed. The provascular bundles of the pith plexus arose
independently and developed acropetally from the base of the future node. Early dif-
ferentiation of proto-phloem and -xylem in the main procambial strands proceeded
bidirectionally up the leaf primordia and down the stem from a site of initiation isolated
from other differentiated vascular elements. Further development was basipetal from
the tip of the primordia, and the rate of differentiation of the sieve elements was
sufficient to maintain phloem continuity across the intercalary meristems of the laminae,
sheaths, and internodes. Within the developing nodes sieve tube differentiation in
the cross-linking strands lagged behind that of the leaf traces they interconnected, and
this may influence the movement of photoassimilate from a recently expanded leaf
to the apex.
Frost Resistance in Eucalyptus : a New Method for Assessment of Frost Injury in Altitudinal Provenances of E. viminalis
Authors: Paton DM
Published: December 2005

Seedlings of E. viminalis were grown under controlled environment conditions
and exposed to single frost treatments between - 1 and -5°C. A new objective method
for assessment of frost injury was developed on the basis that killed leaf tissue lost
water until equilibrium was established with atmospheric moisture. The percentage
ratio of dry weight to wet weight was found to increase ? 30% for unaffected plants
to 85% for killed plants, and intermediate values provided a reliable quantitative
assessment of the severity of intermediate injury.
There was no clear relationship between frost resistance and growth rate. Frost
resistance increased with increase in altitude of seed source above 1000 ft, but the sea
level provenance proved to be as frost-resistant as the provenance at 3600 ft, which
suggested that more than an altitudinal cline for frost resistance is involved. Further-
more, variation in frost resistance within half-sib families and within provenances was
often significant and of the same order as the variation between provenances. Thus
frost resistance in E. viminalis appears to involve several different mechanisms.
Within-provenance and within-family variability was characterized by a low frequency
of plants with intermediate injury, and the implications of balancing selection between
susceptible and resistant phenotypes as one possible mechanism for this, are discussed.
Die-back in the mixed hardwood forests of eastern Victoria: A preliminary report
Authors: Marks GC , Kassaby FY , Reynolds ST
Published: December 2005

The distribution and symptoms of die-back in the mixed-species eucalypt
hardwood forests of eastern Victoria are described. The disease was recognizedin 1952
in small patches of forest situated in the flat, badly drained sandy coastal soils and has
spread rapidly. This spread was associated with above-average rainfall during spring,
summer, and autumn. Disease symptoms were similar to that caused by drought, and
were observed best during dry periods following summer rain.
The lupin bait of Chee and Newhook was used to isolate Phytophthora cinna-
momi from the diseased areas, and the field symptoms seen on susceptible eucalypts of the
subgenus Renantherae were similar to those observed on young saplings inoculated with
P. cinnamomi in the greenhouse. Species of the subgenus Macrantherae observed in the
forests and tested in the greenhouse are tolerant to the disease. Estimates of population
density indices of the fungus gave highest values in areas where the disease was most
active. The fungus was not isolated from adjacent healthy forests.
Improvements in the baiting and identification of P. cinnamomi with use of
excised lupin radicles floated over a small sample of soil in a petri dish are described.
Several variants of the fungus with differing growth rates were isolated.
The morphology and anatomy of proteoid roots in the genus Hakea
Authors: Lamont B
Published: December 2005

This paper extends the introductory work of Purnell(1960) on proteoid roots in
the family Proteaceae by a detailed study of the genus Hakea, with special reference to
H. prostrata. The presence of proteoid roots is reported in 63 Hakea species. Their
relative contribution to the root system is related to such plant factors as species, age,
and cotyledon size. The dimensions of proteoid roots are dependent on plant age and
species. The morphology and anatomy of these structures are described. Endophytic
microorganisms are not normally associated with proteoid roots. Proteoid rootlets
survive 2-3 months, though their parent roots last indefinitely.
Proteoid roots are produced by the youngest roots in the root system. While
proteoid rootlets arise laterally, the parent root may arise either laterally or adventitiously.
Both proteoid and non-proteoid roots may be initiated within a proteoid root.
Soil Surface Lichens in Arid and Subarid South-Eastern Australia. III. The Relationship Between Distribution and Environment
Authors: Rogers RW
Published: December 2005

From a consideration of the distribution of species and species groups in
relation to soil and climatic factors, it is shown that mean annual rainfall and mean
maximum January temperature largely explain the distribution pattern of arid zone
soil surface lichens. A past distribution of lichen crusts in southern Australia is
postulated on the basis of factors controlling lichen crust development, and known
variations from this pattern explained in terms of stocking history.
The Invasion of Native Forest by Phytophthora cinnamomi. III. Threat to the National Park, Wilson's Promontory, Victoria
Authors: Weste G , Law C
Published: December 2005

Diseased vegetation was first reported from the northern slopes of the
Vereker Range at Wilson's Promontory National Park in September 1970. Phytophthora cinnamomi was isolated from plants in diseased areas but not from unaffected
localities. The pathogen has since invaded three types of plant community-dry
sclerophyll woodland, heaths, and swamps-and can be isolated at all depths to
80 cm in deep sands. High inoculum potentials are found at depths of maximum
root concentration, i.e, to about 32 cm. Except where free water occurs, the rate
of extension of the disease is slow. Dominants of both tree and shrub strata are
susceptible and have been killed. Highly susceptible shrubs of the understorey,
such as Xanthorrhoea australis and Isopogon ceratophyllus, are destroyed first.
These are followed 6-12 months later by less susceptible shrubs, and at least
12 months later symptoms appear in trees. This variation in time may be responsible
for the characteristic mosaic appearance of diseased areas. Inoculation experiments
on 9-month-old trees of Banksia serrata and Eucalyptus obliqua confirmed field
observations of susceptibility and symptom expression. The origin of the disease at
Wilson's Promontory and its ecological significance are examined. Experiments in
control of the pathogen are reported and recommendations discussed for control
within the National Park.
Studies in the ecology of Nothofagus cunninghamii Oerst. III. Two limiting factors : light intensity and water stress
Authors: Howard TM
Published: December 2005

The observation that Nothofagus cunninghamii seedlings survive only under
canopy gaps in closed Nothofagus forest led to an investigation of the light compensation
point for this species.
The light compensation point of 6-month-old N. cunninghamii seedlings was
determined as 1 .15 % of full summer sunlight. This is considerably higher than that
for Eugenia smithii (0.1 %), and explains the difference in seedling regeneration
patterns in these structurally and floristically similar forest types. It is closer to that
for Eucalyptus regnans (1.5-1.7 %), but the slight difference may be sufficient to
explain the ability of Nothofagus to invade an E. regnans forest where E. regnans
seedlings themselves are unable to survive.
N. cunninghamii has failed to spread onto drier sites at Mt. Donna Buang,
which may be due to its low drought tolerance. However, experiments indicate
that N. cunninghamii seedlings are more drought-resistant than might be anticipated
from their wet cool habitat. Two-year-old seedlings in the glasshouse survived up to
7 weeks without watering, as did some younger ones. The relative turgor of leaves
at incipient death was 70 %.
Observations on planted seedlings in the field and natural coppice Nothofagus
during the severe drought of the 1967-68 summer suggested that summer water stress
is one of the factors confining Nothofagus to cool moist positions, though such severe
selection may only be effected once or twice in a century.
Parmelia reptans, a new lichen species producing the depsidone, succinprotocetraric acid
Authors: Baker C , Elix JA , Murphy DPH , Kurokawa S , Sargent MV
Published: December 2005

The new lichen, Parmelia reptans, is described and shown to produce the depsidone,
succinprotocetraric acid. This lichen acid has been characterized and identified
as l'-carboxy-2',4-dihydroxy-6,6'-dimethyl-3-formyl-3'-succinoyloxymethyldepsidone.
Succinprotocetraric acid has also been isolated from Chondropsis semiviridis and
detected in several other lichen species by microchemical methods.
Studies on the Origin, Evolution, and Distribution of the Gramineae. V. The Subfamily Festucoideae
Authors: Hartley W
Published: December 2005

Maps are presented showing the world distributions of the subfamily Festucoideae and the tribe Festuceae, based on data on relative specific frequency derived from about 500 widely-distributed floras and floristic lists. The maps show many points of similarity and, especially in N. America, there is a very high correlation between the numbers of species of the subfamily and tribe in regional floras. Both the Festucoideae and the Festuceae attain their highest relative specific frequency in high latitudes or at high altitudes. There is a strong negative correlation between high specific frequency and midsummer temperature in the flora of the United States, and evidence of a similar, though less marked, relationship in other regions. The effect of rainfall is not apparent in the distribution maps. Regions of high relative specific frequency of the tribes Agrostideae, Aveneae,
Stipeae, and Triticeae are mapped, and discussed in relation to climate. In their
geographical relationships, the tribes studied fall into two groups, viz. (1) Agrostideae,
Aveneae, and Festuceae; (2) Stipeae and Triticeae.
The significance of the distribution patterns is discussed in relation to the
evolutionary development of the subfamily Festucoideae and its constituent tribes.
The phytogeographical evidence supports the view that each tribe is monophyletic,
with the exception of the Aveneae (sensu str.), which is well developed in regions of
diverse climate. A strongly developed enclave of high relative specific frequency of
Festuceae in part of south-eastern Europe, which shows no obvious relationship to
climate, is interpreted as evidence for the occurrence of a cycle of secondary evolution
of the tribe in this region.
Rainfall Partitioning by an Arid Woodland (Acacia aneura F. Muell.) In South-Western Queensland
Authors: Pressland AJ
Published: December 2005

In this study of rainlfall characteristics, throughfall was high!y positively cor-
related with precipitation. Stemflow and interception were positively correlated with
precipitation. Rainfall intensity did not significantly affect the stemflow or interception
components, though throughfall was shown to increase with increasing intensity for
rainfall events up to 6 mm aggregate. A positive relation was shown between tree size
and interception, while negative relationships were found between tree size, and
throughfall and stemflow for various classes of precipitation events. Volume of stem-
flow waters was positively related to tree size. The results are discussed in terms of soil
infiltration characteristics, and the woodland community.
Inosculate Analysis of Vegetation Data
Authors: Dale MB , Anderson DJ
Published: December 2005

Traditional tabular sorting practices emphasize the differential importance of
species within stand groups. Such a method orders (ordinates) the species while classi-
fying stands, and by symmetry an inverse analysis will ordinate stands while classifying
species. In this paper some methods of defining group structure which permit choice
at any division between normal and inverse approaches are examined. One of these,
the two-parameter method, also permits monotonic variation within groups, and in
this case the choice of normal or inverse analysis is equivalent to a choice of classi-
fication or ordination alternatives. Such an analysis is termed inosculate.
In comparison with a quantitative information analysis, the two-parameter
method provides a more detailed and informative representation, although the division
procedure is monothetic. The establishment of dominance, constancy, and fidelity
criteria is examined, and the environmental interpretation of species and stand groups
attempted. While the analysis is computationally time-consuming for quantitative data,
it is certainly very rewarding. Some alternative approaches permitting inosculate
analysis are also briefly examined.
Phytophthora cinnamomi — the Cause of Severe Disease in Certain Native Communities in Victoria
Authors: Weste G
Published: December 2005

Evidence is provided that die-back disease in certain Victorian sclerophyll forests is caused by one
fungus, P. cinnamomi. The pathogen is not a common soil component but has evidently been intro-
duced with road-making and soil or gravel transport. Preliminary results are presented of the
effects of severe bushfire on the presence of inoculum at various soil depths. The implications
resulting from investigations into disease in Victorian forests are discussed with reference to work
published on disease associated with the same pathogen in more northern areas of coastal Australia.
Pathogenicity to Three Agricultural Plant Species of Phytophthora drechsleri Isolates From Australian Forest Communities
Authors: Pratt BH , Heather WA , Shepherd CJ
Published: December 2005

The pathogenicity of 35 isolates of Phytophthova dvechsleri obtained from native forest and other
sources throughout Australia was examined, with Carthamus sp., Helianthus sp. and Citrullus sp. as
the test hosts.
Fourteen southern and 20 northern ecotypes of the fungus were pathogenic to Carthamus but not
to Helianthus or Citrullus; a single isolate of the A1 mating strain was non-pathogenic to all three
hosts.
The relevance of these findings to agriculture and forestry is discussed.
Wood Characteristics of Sexually and Vegetatively Reproduced Pinus radiata
Authors: Nicholls JWP , Brown AG , Pederick LA
Published: December 2005

Grafted ramets derived from mature ortets and open-pollinated seedling offspring of the same
ortets, of the same age and growing under the same conditions, were sampled at two localities.
Significant differences in ring width, average tracheid length and densitometric parameters were
observed in the wood from the ramets and the open-pollinated progenies. It is suggested that these
differences are due to the effects of cyclophysis.
These findings generally supported a preliminary investigation dealing with differences observed
between ortets and their associated ramets.
Leaf Anatomy of Australian Saltbushes in Relation to Photosynthetic Pathways
Authors: Osmond CB
Published: December 2005

The leaf anatomy of 44 members of the genus Atriplex endemic to Australia was examined. With 1 exception all members of the genus showed the Kranz type of leaf anatomy typical of plants with the C4 photosynthetic pathway. Only A. australisica lacked Kranz anatomy and showed a C isotope discrimination ratio typical of plants with the C3 photosynthetic pathway.
Fungal and Insect Parasites Contributing to Niche Differentiation in Mixed Species Stands of Eucalypt Saplings
Authors: Burdon JJ , Chilvers GA
Published: December 2005

Parasitic damage to the leading shoot of young regrowth eucalypts was found to vary considerably
between trees and between different stands but it averaged greater than 20 % 'effective leaf area loss'
overall. Many fungal parasites and some of the phytophagous insects responsible for this damage
exhibited host specificity or host preference towards trees of a particular subgenus of Eucalyptus.
These findings are discussed in relation to the hypothesis that parasites play an important role in
the maintenance of stable associations between codominant species of Eucalyptus.
Silica in Woody Stems
Authors: Scurfield G , Anderson CA , Segnit ER
Published: December 2005

Scanning electron microscopy has been used to examine silica isolated by chemical means from the
wood of 32 species of woody perennial. The silica consists of aggregate grains lying free in the
lumina or in ray and xylem parenchyma cells in 24 of the species. It occurs as dense silica in the other
species, filling the lumina or lining the internal surfaces of vessels (and fibres) in all cases except
Gynotroches axillaris where it is deposited in ray parenchyma cells. Infrared spectra and X-ray
diffraction diagrams, obtained for specimens of both sorts of silica, are indistinguishable from those
for amorphous silica. Aggregate grain and dense silicas are also alike in that their differential thermal
analysis curves show a rather broad endothermic peak between 175° and 205°C. The results are
discussed in relation to possible modes of deposition of the two sorts of silica and the tendency for
silica in ray parenchyma cells to be associated with polyphenols.
Complex hybridity in Isotoma petraea. IV. Heterosis in interpopulational hybrids
Authors: Beltran IC , James SH
Published: December 2005

Discriminant analysis of four structurally homozygous populations of Isotoma petraea showed that they are significantly different with respect to phenotypes produced in a standardized environment and hence they are genetically different. These populations are relatively homozygous for different arrays of genes and their interpopulational hybrids exhibit a euheterotic increase in aerial dry weight. The individual natural populations may be considered as depressed inbred lineages of the relationally balanced base population of I. Petraea. The degree of heterosis observed in their interpopulational hybrids is mainly influenced by the degree of inbreeding that is characteristic of of each population. Negative heterosis was observed in interpopulational crosses among complex heterozygotes. The complex heterozygotes are genetically heterozygous, and a precise relational balance exists between the complexes associated in the native complex heterozygotes; this coadaptation does not extend from population to population.
Leaf Parasites on Altitudinal Populations of Eucalyptus pauciflora Sieb. ex Spreng
Authors: Burdon JJ , Chilvers GA
Published: December 2005

Preliminary studies of fungal parasites and phytophagous insects on saplings of Eucalyptus pauciflora
Sieb. ex Spreng, growing at different altitudes, suggest that the impact of these organisms is inversely
related to the rigour of the physical environment.
Therapy of Virus-Infected Plants by Heat Treatment I. Some Properties of Tomato Aspermy Virus and Its Inactivation at 36°C
Authors: Johnstone GR , Wade GC
Published: December 2005

An isolate of tomato aspermy virus (TAV) was inactivated both in vivo and in vitro at 36°C. Inactivation took the form of a second or higher order reaction, which indicated that loss of infectivity was
not due solely to a direct effect of high temperature on the virus.
The concentration of polyphenoloxidases increased greatly in tobacco plants grown at 36°C, and
evidence was obtained to indicate that this enzyme class, either directly or indirectly, enhanced the
inactivation of TAV during heat treatment. The concentration of ribonucleases also increased in
heat-treated tissues and these may have aided the inactivation, as the infectivity of TAV was shown to
be destroyed by RNase in tests in vitro. The pH and ionic strength of the sap decreased in heated
plants and these changes may have been significant as TAV had critical requirements of buffer pH and
molarity for optimum infectivity.
The alterations in cellular metabolism responsible for these changes result from heat-induced
stress. Therefore, the optimum temperature for therapy of many viruses by heat treatment is likely
to vary with the host in which it is treated, depending upon the host's heat tolerance.
Therapy of Virus-Infected Plants by Heat Treatment II. Host Protein Synthesis and Multiplication of Tomato Aspermy Virus at 36°C
Authors: Johnstone GR , Wade GC
Published: December 2005

The concentration of ribosomes and of total protein decreased in tobacco plants grown at 36°C, and the
high temperature had a differential action on the rates of synthesis and breakdown of individual proteins. However, the overall rate of protein synthesis in tobacco at 36° was higher than in unheated plants.
It is suggested that one reason for success in the heat therapy of virus-infected plants is that viral RNA
competes poorly with host messenger RNA for the limited numbers of ribosomes on which to sythesize their respective proteins. This concept was supported by the finding that demonstrable
synthesis of tomato aspermy virus (TAV) occurred in tobacco at 36° in the presence of actinomycin D,
an inhibitor of host protein synthesis, but not in its absence. Also, cytokinin applications to heated
plants appeared to stimulate their rate of protein synthesis, and the rate of TAV inactivation was higher
in plants treated in this way. This concept may also be used to account for the successes in obtaining
virus-free material from infected plants by meristem culture.
Cytotaxonomic observations on Villarsia (Menyanthaceae)
Authors: Ornduff R
Published: December 2005

Chromosome counts for five species of Villarsia indicate that x = 9 for the genus. In Australia one species is diploid, two species are hexaploid, and one species has tetraploid and hexaploid races. The South African V. capensis is tetraploid. Seed size differences in V. reniformis are not correlated with differences in ploidy level. One Australian species and V. capensis are distylous and strongly self-incompatible. Two homostylous species in Australia are self-compatible, but V. albiflora is homostylous and self-incompatible. Villarsia capensis is morphologically variable, but seems closely related to eastern Australian species. The amphi-Indian Ocean distribution pattern exhibited by this genus is an unusual one, and it seems doubtful if it can be accounted for by long-distance dispersal. The present range was perhaps achieved at a time when continental positions and climatic conditions were more favourable for overland migration than they are at present.
Anthocyanins in Some Eucalyptus Species
Authors: Sharma PJ , Crowden RK
Published: December 2005

Anthocyanins have been investigated in 23 species from two sections of the genus Eucalyptus.
A total of 17 compounds has been identified in the young leaves and in the bark of first-year twigs.
A correlation is observed between the distribution of anthocyanins and the taxonomy of the species
examined.
Soil microorganisms and the formation of proteoid roots
Authors: Lamont BB , Mccomb AJ
Published: December 2005

Proteoid roots are not formed in sterile soil under conditions which would otherwise allow their
production. This is attributed to the absence of soil microorganisms rather than to an alteration of
chemical components by autoclaving. Water extracts from proteoid roots or their associated soil
did not enhance the formation of proteoid roots. High microbial numbers in the surface soil horizons
are considered largely responsible for the abundance of proteoid roots in these high organic matter
regions. Results of experiments indicate that the formation of proteoid roots is stimulated by soil
microorganisms which themselves do not invade the parent root, though the relevant organisms
have yet to be identified.
Vegetation history and water fluctuations at Lake Leake, south-eastern South Australia. 1. 10,000 B.P. to present
Authors: Dodson JR
Published: December 2005

The stratigraphy and detailed pollen analysis of the top 4 m of sediment in Lake Leake were used
to describe the vegetation history and past changes in the water level in the lake basin. Some of
the changes described have climatic significance. Six radiocarbon dates are used to place a chronology
on these events and the results are used to compare previous work carried out in western Victoria.
It is suggested that in south-eastern South Australia, immediately prior to 10,000 B.P., conditions
were drier than at present and that after this time conditions became wetter, the wettest period of
the last 10,000 years occurring between 6900 and 5000 B.P. After this time conditions became drier,
marginally wetter again between 2000 and 1300 B.P., then relatively dry until the present day. Keys
to aid in the identification of pollen of the Casuarinaceae, Myriophyllum and the Myrtaceae for
species growing in the Lower South-East of South Australia are given.
The southern Australian species of Laurencia (Ceramiales: Rhodophyta)
Authors: Saito Y , Womersley HBS
Published: December 2005

Species of Laurencia along southern Australian coasts are common and often ecologically important.
Sixteen species are recognized from this region, of which L. aldingensis, L. shepherdii, L. brandenii and
L. tumida are newly described. While most species are clearly defined, L. filiformis as recognized
includes three main forms (one of which is based on L. heteroclada), with intergrades between them,
and also some intergrades from it to the related species L. arbuscula and L. tasmanica. Most southern
Australian species appear to be confined to this region and their biogeography is discussed; the
widely distributed L. obtusa probably does not occur in southern Australia.
Dark Island Heath (Ninety-Mile Plain, South Australia). VIII. The Effect of Fertilizers on Composition and Growth, 1950-1972
Authors: Heddle EM , Specht RL
Published: December 2005

In the early 1950s fertilizers, i.e. phosphorus, nitrogen, copper and zinc, were added in various
factorial combinations to raise the fertility of an area of native heath vegetation to that of the more
fertile soils found in southern Australia. The first 10 years of observations on the effects of increased
soil fertility on the composition and growth of heath vegetation were reported in 1963. The field
experiment was re-examined in 1972.
No significant response to the application of nitrogen, copper, or zinc has been observed in this
experiment. A response to nitrogen plus phosphorus was reported previously; no response to any
other essential nutrient has been demonstrated in the field.
Phosphorus fertilizer showed five effects which, collectively, have gradually changed the heath
vegetation towards an 'herbaceous sward' over the last 22 years.
(1) Much of the phosphorus fertilizer applied in 1950-1953 was retained in the ecosystem for at
least two decades.
(2) The fertilizer increased the growth of well-established 'adult' species of heath, and tended to
speed up their life cycle and cause them to die many years earlier than usual.
(3) Herbaceous species with a spring peak of growth which gave them a competitive advantage
(for water and nutrients) over heath seedlings which produced new shoots towards the end of spring
and over summer invaded the fertilized heath.
(4) 'Phosphorus toxicity' and water stress in competition with invaders induced the death of
almost 100% of the seedling heath species.
(5) Bushfires, an integral part of this ecosystem, released phosphorus stored in above-ground
vegetation to the surface soil; seedling regeneration of the heath was further inhibited by this
accession of nutrient.
The conservation of heath vegetation subjected to phosphate contamination from adjacent farms
and forest plantations, and from litter (even fruit peelings) deposited along tracks, poses a major
problem in the management of conservation areas.
The Seasonal Growth of Eucalyptus regnans F. Muell
Authors: Ashton DH
Published: December 2005

At Wallaby Creek, Vic. (altitude 670 m), Eucalyptus regnans seedlings 1-6 m in height usually
commence growth in early September, reach maximum growth in midsummer and cease growing
in late May. The active growing season when shoot growth exceeds 12 mm per month is 7-9½.
months. Slow growth occurs in midwinter in Melbourne (altitude 47 m) and is not affected by day
length.
The growth rates of seedlings of associated understorey species are, in descending order of
magnitude: Acacia dealbata, E. vegnans, Prostantheva lasianthos, Pomadevvis aspeva, Acacia
melanoxylon. Their growth periods are similar, except for that of A. melanoxylon which is much
shorter.
Leaves of E. regnans mature in 2½-3½ months. In larger seedlings some of the leaves produced
are initiated during the growing season. The size of the mature leaf depends partly on the season
of its emergence.
In winter and spring, die-back of apical shoots occurs in most seedlings owing to weevil attack
and fungal infection. Insects may severely damage young leaves, but rapid recovery in full light
takes place by the development of axillary and accessory buds.
Maximum diameter growth rates tend to occur in November just prior to the main peak of shoot
extension. Further increases in diameter may occur in April, and slight shrinkage may take place
in late summer and midwinter.
The period of active growth can be correlated with the period over which the air temperatures
at 1.3 m above ground exceed a daily mean of 5.0-7.5°C, a daily maximum of 12.8° and a weekly
maximum exceeding 15.5°. Growth,resumption may be delayed until weekly minimum air tempera-
tures rise above - 2°. The mean temperatures at 1.3 m are roughly the mean of air temperatures
from the top and base of the shoot. The mean temperatures at the mean commencement and
cessation of growth differ by only 0.6-1.6°C, whereas the day length differs by 1½ hr.
Growth rates correlate strongly with mean temperatures (particularly mean maximum tempera-
tures) in spring and early summer. The wide deviations which occur in late summer and early
autumn may be attributable to depletion of soil water reserves.
Chromosome numbers in the Gyrostemonaceae Endl. and the Phytolaccaceae Lindl.: a comparison
Authors: Keighery GJ
Published: December 2005

New records for the genera Codonocarpus (n = 14), Gyrostemon (n = 14) and Tersonia (n = 14) are given. The base number for the family Gyrostemonaceae is shown to be x = 14: this is markedly different from that of the Phytolaccaceae sensu stricto (x = 9), in which it was once included.