bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental morphogenesis in adventitious buds of flax
Authors: Gulline HF
Published: December 2005

The polar development of adventitious buds and their associated vascular traces in flax hypocotyls has been studied, and experiments performed with the object of altering this polarity. Buds ware induced on portions of epidemal tissue grafted in inverted positions on hypocotyls, and on hypocotyls subjected to reversal of the direction of gravity and electric polarity normally acting on them. The effects of experimental incisions into adventitious meristems, and in close proximity to them, were also studied. The basic pattern of development remained constant under all treatments. These experiments show that the epidermal and cortical cells from which the adventitious buds and their dependent vascular traces develop possess a very strong inherent polarity which could not be varied by extracellular changes of field.
Observations on the gametophytes of Grammitis billardieri Willd. and Ctenopteris heterophylla (Labill.) Tindale (Grammitidaceae)
Authors: Stone IG
Published: December 2005

An account is given of the spores, germination, and vegetative features of the prothalli of Grammitis billardieri and Ctenopteris heterophylla, and of the reproductive organs of G. billardieri. The characteristic germination is unlike that found in other ferns. The trilete green spore frequently divides in the unruptured sporangium and the first division produces two equal prothallial cells. Growth is extremely slow, the filament long and often branched, and the rhizoids which appear late may branch. The first longitudinal division occurs in a cell back from the apex, and the gametophyte at maturity is elongated and ribbon-like, with or without a slightly indented apex, brown marginal rhizoids, and discontinuous axial cushions two to three cells thick. The thallus, which is extremely slow in reaching maturity, is dark green, and the walls perpendicular to the surface are pitted. Regeneration is common. The most distinctive feature of the gametophyte of G. billardieri is the development of characteristic spine-like hairs unlike those found on fern prothalli of other families. These hairs are marginal in the anterior region and develop from wedge-shaped initial cells. They differ in form and origin from those found in members of the Polypodiaceae. The antheridia appear at an unusual stage in development, occurring after some of the archegonia have been produced and forming with them on the cushions. The archegonia have longer necks and the antheridia are slightly more complex than those found in members of the Polypodiaceae which have been investigated. It is considered that the separation of the family Grammitidaceae from the
Polypodiaceae on sporophytic characters is supported by the gametophytic generation of the two Victorian grammitid ferns G. billardieri and C. heterophylla.
The fine structure of the pits of Eucalyptus regnans (F. Muell.) and their relation to the movement of liquids into the wood
Authors: Cronshaw J
Published: December 2005

Observstion in the electron microscope of carbon replicas of the pits of vessels, ray parenchyma cells, fibres, and tracheids of Eucalyptus regnans has shown the detailed structure of the pit borders and the pit closing membranes. In all cases in the mature wood the primary wall is left apparently without modification as the pit membrane. Unlike the borders of the pits of fibre tracheids and tracheids, the pit borders of the vessels are not separate; the cellulose microfibrils of a border may be common to several pits. The pit borders of fibre traoheids and tracheids are developed as separate entities and have a structure similar to the pit borders of softwood tracheids. The structure of the secondary wall layers associated with the pits is described and related to the structure of the pits. The fine structural features of the pits, especially of the pit closing membranes, are discussed in relation to the movement of liquids into wood.
The distribution and cytology of the chromosome races of Themeda australis in southern Australia
Authors: Hayman DL
Published: December 2005

Thermeda australis (R.Br.) Stapf is a polyploid complex based on n = 10, and
diploid, triploid, tetraploid, pentaploid, and hexaploid individuals have been found. Over 98 per cent. of more than 800 individuals examined were either diploid or tetraploid. Some 300 populations, from localities on the Australian mainland below the Tropic of Capricorn, were characterized by their chromosome number and a very clear pattern of distribution was found. Diploid populations occur exclusively on the Eastern Highlands and slopes in southern Victoria and in Tasmania; elsewhere tetraploid populations occur across to Western Australia. Triploid, pentaploid, and hexaploid plants are found as individuals in populations of another chromosome number. The cytological evidence shows a very close relationship to exist between the constituent genomes of the polyploids. The significance of the distribution of the chromosome races, the effects of polyploidy, and the implications of this pattern for further studies on the native flora are discussed.
Hook-shaped opal phytoliths in the epidermal cells of oats
Authors: Baker G
Published: December 2005

Among several species of the Gramineae, Avena sativa L. (oats) is an important opal-accumulator plant in Victoria. In it, amorphous silica has been precipitated as very abundant microscopic opal phytoliths of various shapes, among which hook-shaped forms are common in alternating rows of epidermal cells. Examples studied in detail were observed within and isolatd from oats grown on basaltic soil on "Barewood Farm", approximately 2 miles north of Clarkefield in the Romsey district of South Central Victoria. They are variable in shape and size, and in their relationships to adjacent rod-like opal phytoliths that infill the lumen of several of
the subepidermal cells. Each hook-shaped opal phytolith consists typically of a solid core of opal enveloped distally by a more delicate cone-like sheath of opal. The opal of the sheath is hyaline and transparent compared with the thicker, generally translucent core. Refractive index variations reveal differences between core and sheath, and between the several growth layers of slightly different composition in the sheath. These differences reflect variable ratios of silica to water in the opal of the core, the sheath, and its several layers. The hook-shaped opal phytoliths, like all other shape types secreted in short-lived plants, must have developed rapidly, because processes of opal precipitation and solidification were completed within the compass of one
growth season.
Floral histogenesis in the Monocotyledons. IV. The Liliaceae
Authors: Barnard C
Published: December 2005

An account is presented of floral histogenesis in Bulbine bulbosa R.Br. and Stypandra glauca R.Br. The apex of the floral axis in both species has a two-layered tunica, and bracts arise through the periclinal division of cells of the inner layer of the tunica (hypodermis). In Bulbine, axillary flower primordia are initiated in the periclinal division of subhypodermal cells; in Stypandra the flower primordia are terminal and arise directly from the apices of branches of the inflorescence. In both species the perianth'members originate, in the same manner as the bracts, through periclinal divisions in cells of the hypodermis. Periclinal divisions may occur in the cells of the outer tunica layer (dermatogen) after the prinlordia are well formed. Divisions in subhypodermal cells in the area of perianth initiation are associated with the formation of a provascular strand and it is doubtful if such divisions contribute anything to the tissue of the perianth primordium itself. The stamens are initiated in the periclinal division of both hypodermal and subhypodermal cells. In Bulbine the carpels develop through periclinal divisions in the hypodermis and dermatogen. The placentas appear to arise through divisions in subhypodermal cells as structures adnate to the carpels. In Stypandra the carpels arise in a quite different manner through the periclinal division of subhypodermal cells. The margins of the carpels develop as the placentas and there is no suggestion in the early ontogeny of the gynaecium that the placentas have an independent origin.
Anatomical and morphological studies in the Chenopodiaceae. I. Inflorescence of Atriplex and Bassia
Authors: Bisalputra T
Published: December 2005

Antomical techniques were employed to explain the morphology of the inflorescence of certain Australian species of Atriplez L. and Bassia All. Clearing of tissues by chlorallactophenol was used extensively and proved to be superior to the slow conventional method of sectioning and reconstruction. Vascularization of the stem and the inflorescence was studied and described. It was found that the inflorescences of Atriplex are of two types. One is terminal in origin; and the second is axillary, containing female flowers, and is complex, being a much condensed form of compound dichasium. The lateral branches of such an inflorescence are always dichasia of female flowers, but the terminal branch is variable and can be either a male dichasium, a female flower, or a vegetative shoot. The solitary flower of Bassia is derived from the suppression of the lateral branches of such an inflorescence and a reduction in the number of flowers in the terminal branch. Two species of Bassia, however, bear an inflorescence which is a condensed dichasium. Attention is drawn to the similarity of the vascular system of the male inflorescence of Atriplex and the primary vascular system of the Bassia stem. The development, morphology, and anatomy of the fruiting bracteole of Atriplex is described in some detail and it is concluded that it is a true bracteole.
Some observations on the life history of Podocarpus falcatus
Authors: Osborn TGB
Published: December 2005

Podocarpus falcatus (R.Br. ex Mirb.) belongs to the 1-year life cycle type of podocarp. Ripe seeds are shed 12–13 months after pollination. There is a single gynospore mother cell in a well-defined tapetum, and the inner spore of a linear tetrad is functional. Pollen tubes make contact with the developing female prothallus before the stage of free nuclear division is complete. They continue to grow downwards between it and the nucellus. There are several superficial archegonia, some of which may be enveloped by a common jacket layer. They are of
intermediate length, and develop along the line of contact between the pollen tube and prothallus. The gynospore layer membrane remains thin at this point. Five free mitoses of the zygote nucleus take place, the first two in the mid archegonial area. The proembryonic nuclei become tiered with a low number in the embryonic layer. The embryonic cells have the usual binucleate phase followed by tetrad formation. Simple polyembryony is common, and though fission may occur it is not general.
Destruction of indigenous heath vegetaion in Victorian sea-bird colonies
Authors: Gillham ME
Published: December 2005

The sclerophyllous heath and scrub which occupies undisturbed granite coasts is essentially a vegetation of infertile, acid soils deficient in available phosphorus and nitrogen and sometimes in potassium and certain microelements. In sea-bird colonies soil reaction and fertility are altered by the deposition of guano, which is rich in phosphorus, nitrogen, and potassium, and the indigenous heath and scrub are destroyed. Mechanical disturbance and chemical changes hinder the accumulation of surface peat. Toxicity of guano in summer leads to a specialized flora and limits the total number of species. Comparison of floristic data from sea-bird islands and nearby control areas with no nesting sea-birds illustrates the widely divergent nature of the flora in the two habitats. Heath species are almost non-existent in the rookeries, and sclerophylls, switch plants, and woody plants much rarer than in the control areas. Conversely, succulents, annuals, biennials, and aliens are considerably more abundant in the rookeries. Man is the primary introducer of alien plants; but gulls are also important in this respect, and all colonial sea-birds make the habitat more suitable for invasion by ruderals in the autumn when mechanical disturbance ceases and guano becomes diluted to beneficial concentrations. Where man has access to the rookeries large areas may become dominated by introduced weeds which are seldom able to establish themselves on unmodified heath soils. The vegetation of sand dunes (to which few nutrients are being added and from which few have been leached) lies between that of the leached soils of heaths and the guano-rich soils of rookeries overlying granite in all the above characters, in spite of the markedly different physical nature of the substratum, and contains a higher proportion of creeping plants than either. Guano and sea salt have parallel effects on vegetation, and the presence of sea-birds leads to a broadening of the coastal belt of salt-resistant plants and elimination of the indigenous, more inland type of flora. Pteridium esculentum and Leptospermum laevigatum are important species in the transition zone between either saline or guano-rich habitats and the surrounding heath.
Studies in the Cunoniaceae. I. The genera Ceratopetalum, Gillbeea, Aistopetalum, and Calycomis
Authors: Hoogland RD
Published: December 2005

This first series of studies in the Cunoniaceae offers revisions of the genera Ceratopetalum Sm., Gillbeea F. Muell., Aistopetalum Schltr., and Calycomis D. Don. Full synonymy, bibliography, descriptions, and critical notes are given for the genera and species, and keys to the species are included. The genus Cemtopetalum comprises five species in eastern Australia and New Guinea. C. tetrapterum Mattf., described from New Guinea, is reduced in synonymy under C. succirubrum C. T. White, previously known only from northeastern Queensland. The genus Gillbeea comprises two species, one in north-eastern Queensland and one in New Guinea. The genus Aistopetalum comprises two species in New Guinea; one species is widespread in the northern parts of the island, the other is known only from the type collection. A. tetramerum Kan. et Hat. is reduced in synonymy under A. viticoides. The genus Calycomis is monotypic; its only species, C. australis (A. Cunn.) Hoogl. comb. nov. (Weinmannia australis A. Cunn.) is found in the Blue Mountains of New South Wales and is currently known as Acrophyllum verticillatum or A. venosum.
The Australian species of Nicotiana L. (Solanaceae)
Authors: Burbidge NT
Published: December 2005

Since the publication of the comprehensive account of the genus Nicotiana by Goodspeed and his collaborators (1954), extensive collecting by the author has revealed the existence of a number of undescribed species and has resulted in the compilation of data which allow a better understanding of specific relationships between those previously known. In this paper the morphological characters by which species can be recognized are discussed, and five new species and two new subspecies are described. Two of the new species proved to have 23 pairs of chromosomes, thus filling a gap in the series of from 16 to 24 pairs which, with the exception of 17 pairs, has now been recorded for the Australian taxa. Notes on the relationships, the more important morphological features, and the geographical distribution are provided for all previously recognized species.
Further notes on Triodia R.Br. (Gramineae) with description of five new species and one variety
Authors: Burbidge NT
Published: December 2005

Since a revision of Triodia R.Br. was published some years ago (Burbidge 1953) several new species have been collected and facts concerning the distribution of others have been accumulated. Two new species and one variety are described here from plants obtained in central Australia. Two new species from the North West Division and one from bhe Kimberley Division of Western Australia are also described. The opportunity is taken to discuss the circumscription of a few species and the distribution of others formerly known only from type material.
Anatomical and morphological studies in the Chenopodiaceae. II. Vascularization of the seedling
Authors: Bisalputra T
Published: December 2005

An account is presented of the development of the vascular system of seedlings of Atriplex L., Bassia All., Kochia Roth, Malacocera R. H. Anderson, Salicornia (Tourn.) L., and Arthrocnenzum Moq. and the anatomy of the cotyledons is described. The procambial strands of the cotyledons are continuous with those of the hypocotyl-radicle axis but the maturation of the first protoxylem elements occurs independently in each system and eventually they come into contact side by side. There is a certain amount of intrusion by each trace into the tissues of the other. The extent of the transition region between the endarch protoxylem of the cotyledon and the exarch condition of the root as well as the extent of the pith within the hypocotyl and the position of initiation of maturation of the protoxylem elements seems to be determined by the manner in which the hypocotyl elongates. Almost invariably, seedlings of Atriplex, Bassiu, Kochia, and Malacocera which show pronounced elongation in the upper hypocotyl have a long pith and the transition region begins low down and is extensive. Seedlings of Salicornza and Arthrocnemum, on the other hand, have a short pith and the transition region and the initiation of the first protoxylem elements occur at a high level within the hypocotyl. The seedlings of this latter group have a very pronounced elongation in the lower part of the hypocotyl. There is no intermediate condition between -the vascular system of the epicotyl which has endarch protoxylem and the root with the exarch condition, but connexion between the two is established simply by their coming into contact side by side; this occurs in the cotyledon-radicle transition zone. It seems, in the light of this developmental study, that initially there are three separate systems of vascular tissues within the seedling, those of the epicotyl, the cotyledon, and the radicle, but further evidence is needed before a definite conclusion can be made and this could be obtained by an embryological study of the group.
The effects of temperature and day length on species of Eucalyptus
Authors: Scurfield G
Published: December 2005

Seedlings of Eucalyptus bicostata, E. blakelyi, E. niphophila, E. pauciflora, E. polyanthemos, E. rubida, and E . Stelldata were grown under various defined temperature and day-length regimes and response was assessed in terms of height, dry weights of stems, roots, leaves, and branches, number of leaves and branches, and leaf shape. Seedlings of E. bicostata, E. blakelyi, E. niphophila, E. pauciflora, and E. Rubida were capable of continuous growth under short days (8 hr) provided temperature conditions were appropriate. These species can be allocated, therefore, to Class C of Nitsch (1957). Growth was greater under long days of 18 hr than under short days of 8 hr. Irrespective of the temperature regime operating, the order of dry weight increase over 60 days was: E. bicostata > E. blahelyi > E. polyanthemos > E. niphophila. Growth of E. bicostata, E. blalcelyi, and E. polyanthemos increased as mean temperature levels increased thus: 14/8°C, 19/11°C, 20/17°C, 25/20°C. Further increase to 27/24°C had an adverse effeot upon growth of E. polyanthemos, but not on that of E. bicostata and E. blakelyi. Increasing night temperature from 6°C to 24°C when the day temperature was either 11, 20, 24, or 28°C generally increased height, dry weights of stems, roots, and leaves, and total leaf area of E. blakelyi. Similar effects were produced when day temperatures were increased from 11°C to 2S°C, night temperatures being either 6, 16, 19, or 24°C. Consequently, under short days of winter, the 28/24°C regime was most nearly optimal for growth. Adverse effects on growth appeared to be produced when night temperature exceeded a low day temperature (as under the 11/24°C regime). Average day and night temperature interacted in a statistically significant way upon growth. In E. paucifiora, increasing night temperature from 8°C to 24°C when the average day temperature was either 14, 20, 25, or 27°C, and increasing day temperature from 14°C to 27°C when night temperature was 8, 17, 20, or 24°C increased growth. Thus, the regime 27/24°C approached the optimum for growth, as in E. blakelyi. In E. blakelyi and E. paucifiora, branching was most restricted in plants which were tallest. There were indications that the magnitude of diurnal temperature fluctuations might be important in determining the degree of lateral branching (apical dominance). Leaf size, shape, and number were related to day length and temperature conditions. Leaf shape (as measured by length/breadth ratios) was a function of day and night temperatures, not being significantly related to either alone. Day length appeared to exert a more pronounced effeot upon leaf shape (long days tending to shift shape in the direction juvenile → adult) than temperature. The ratios top/root and leaflstem, especially the latter, were significantly lower in E. blakelyi than in E. pauciflora.
Mycorrhiza in the New Zealand Ericales
Authors: McNabb RFR
Published: December 2005

The New Zealand species of the Ericaceae and Epacridaceae examined possessed mycorrhizas anatomically similar to those of Calluna and Vaccinium. The endophyte of Pernettya macrostigma was isolated and successfully back inoculated into the host, under controlled conditions. Its taxonomic identity was uncertain because of its reproductive sterility. A fungus indistinguishable from the ericaceous endophyte was found to form mycorrhizas with Dicotyledons other than the Ericales.
Cytotaxonomy of Australian Danthonia
Authors: Brock RD , Brown JAM
Published: December 2005

Cytological and cytogenetic studies of 29 Australian species of Danthonia revealed an extensive polyploid series ranging from 2n = 24 to 2n = 120. Meiosis was regular and fertility high in the species. Field hybrids were detected by aberrant chromosome number, meiotic behaviour, and reduced fertility. An extensive series of interspecific crosses resulted in some viable hybrids but many combinations failed or gave F1 plants which failed to flower. Most viable F1 plants were highly sterile. Diploid hybrids were completely sterile, but in higher polyploids crossing was more often successful and hybrids had increased fertility. Meiotic pairing and chiasma frequency were drastically reduced in all F1s. Multivalent associations indicated gross structural rearrangements. The restoration of fertility by chromosome doubling indicated cryptic structural changes. Neither cross compatibility nor meiotic behaviour showed any strong relationship with taxonomic grouping. These results together with the intermediate morphology of F1s and the increased morphological variation in polyploid forms of D. caespitosa and D. linkii strongly suggest alloploidy as the main mechanism of evolution of the polyploid species. Twenty-three of the species had Panicoid type of epidermis and Festucoid chloroplast arrangement. The exceptions were D. pallida, D. procera, D. frigicla, D. nivicola, D. nudiflora, and D. sp. indescr. These studies throw light on the relationship of the arid form, D. bipartita, the alpine forms D. frigida, D. nivicola, and D. nuclifiora, and the highly variable forms such as D. caespitosa and D. linkii with the rest of the genus. Plant improvement by conventional methods would be virtually impossible unless restricted to high polyploids and intraspecific crossing, but true-breeding, highly fertile amphidiploids could be produced.
Competition between Eucalyptus melliodora and E. rossii at varying levels of exchangeable calcium
Authors: Moore cWE
Published: December 2005

E. rossii and E. melliodora were grown in pot culture as competing species
at varying levels of exchangeable calcium. Both height and yield of E. melliodora increased with increasing exchangeable calcium.

Regressions of log ratio E. rossii / E. melliodora for both height and yield on exchangeable calcium were highly significant (P < 0.001) and there was no evidence of departure from linearity.

The data indicate that plant growth is influenced by the degree of calcium saturation of the soil rather than by the absolute amount of exchangeable calcium.

The implications of the results in relation to the natural distribution of the two species are discussed.
The Gametophore and Sporophyte of Mittenia plumula (Mitt.) Lindb
Authors: Stone IG
Published: December 2005

An account is given of the gametophore and sporophyte of Mittenia plumula,
stressing those features which have not previously been described.
The moss has a highly refractive lenticular protonema. There is variation
in the arrangement of leaves on sterile and fertile shoots, a shoot may develop one
or more side shoots at its base, and hairs are present in the axils of leaves. The
capsule has a few small stomata at the base, and the inner peristome consists of
28-32 processes.
The double peristome of Mittenia plumula originates from three concentric
layers of cells, the two innermost layers of the amphithecium and the outermost
layer of the endothecium. In all other members of the Bryales whose examination
has included early development, the peristome has been found to develop from
amphithecial tissue only.
The 16 outer peristorno teeth are forined on the periclinwl walls separating
the two outer peristome layers, thickening being laid down on the inner walls of the
outer layer, which is composed of 16 cells, and in adjoining posit'ions on tho outor
walls of the middle layer, which is composed of eight cells.
The inner peristome processes are formed on the periclinal walls separating
the middle from the inner peristome layer (the latter being endothecial in origin).
Thickening is laid down on the inner walls of the middle layer at positions contiguous
with the junctions of the anticlinal walls of the inner layer, which is composed of
24-28 cells. Extra processes usually develop where the anticlinal wall is part of the
original quadrant wall of the embryo. A smaller amount of thickening is then
contributed to the processes from the inner peristome layer.
Variations in the development of the inner peristome are discussed, and a
comparison is made with development of the double peristome of other members of
the Diplolepideae.
Studies on the origin, evolution and distribution of the Gramineae. IV. The genus Poa L
Authors: Hartley W
Published: December 2005

Studies of the regional and global distribution of the genus Poa L, show that
it reaches its highest relative specific differentiation in regions of high latitude and
high altitude. The genus is absent or rare in the tropics, except in mountainous
regions, but constitutes more than 15% of the grass flora of Alaska, Iceland,
Kamchatka, and the high Pamir Mountains.
There is a close association between the occurrence of high percentage
frequencies of species of Poa and cool summer temperatures. In the United States
the 75DF mid-summer (July) isotherm effectively demarcates those regions in which
Poa spp. form more than 5% of the grass flora from those in which they constitute a
smaller percentage. A similar relationship between percentage frequency and
mid-summer temperature is found in most other parts of the world. Climatic factors
other than temperature seem to have little influence on the distribution of Poa.
It is concluded that the genus has attained a high stage of development in
nearly all parts of the world to which it is climatically adapted. The evidence does
not permit firm conclusions about the centre of origin of the genus, but it has a
major centre of species differentiation in the mountain and plateau region of central
Asia. It is probably monophyletic, and has had a long evolutionary history in the
course of which it has spread through regions now separated by topographical or
climatic barriers.
Objective Methods for the classification of Vegetation. IV. Pattern and minimal area
Authors: Goodall DW
Published: December 2005

The structure of salt marshes and mallee scrub in Victoria and rain forest'
in Uganda was studied by means of quadrats forming a continuous grid or transect
or distributed by restricted randomization; the measures used were cover or basal
area. The course of increase in variance as the mean spacing between the sample areas
increased was in most cases found to be continuous, a linear regression between the
logarithms of the variables fitting the data in many oases. In other instances a
quadratic or higher-order regression was indicated, and some of these approximated
to a "stepwise" curve of the type suggested by Greig-Smith and others. This
appeared, however, to be the exception. The theoretical implications of a continuous
increase of variance with spacing are briefly discussed.
The genus Ottochloa Dandy (Gramineae) in Australia and its relationship to Ichnanthus oblongus Hughes
Authors: Lazarides M
Published: December 2005

A taxonomic account is given of the two Australian species of Ottochloa.
One of the species, O. nodosa (Kunth) Dandy, has not been recorded previously
for Australia as such. The taxa, Ichnanthus oblongus Hughes, unidentified in an
earlier paper (Lazarides 1959), and Panicum aequabile Domin, are reduced to
synonymy.
Australian Trees for the Rehabilitation of Waterlogged and Salinity-damaged Landscapes
Authors: Bell David T.
Published: December 2005

The revegetation of damaged agricultural landscapes requires a detailed
knowledge of appropriate species and their adaptations to cope with the
stresses of environments altered by humans. A range of Australian species has
a role in the restoration of water and salt balances of catchments and can
provide income diversity to agricultural properties damaged by increased
frequencies of flooding, rising groundwaters and increased salinities. This
review concentrates on the ecologically significant attributes of Australian
woody species in waterlogged and saline habitats, and responses of species
particularly suited to the restoration of water balance in cleared catchments.
Australian catchments yield little water under natural vegetation, the trees
and shrubs being especially resourceful in utilising much of the annual
rainfall input. Replacing native, deep-rooted perennial species with annual
crops always results in a net gain in catchment water. To redress these
problems, cleared landscapes must be partially restored to tree and shrub
cover to utilise the excess water remaining when crops are harvested or lie
dormant over summer. Upland regions of restored landscapes should be planted
to tree crops, particularly those that are luxuriant water users, of
commercial value to farmers. Tree plantations for paper pulp, soft-wood timber
and eucalypt oils are possibilities. Lowland sites in damaged catchments must
be revegetated with trees which have waterlogging adaptations, such as
aerenchyma, and tolerance to the products of anaerobic respiration. Areas of
waterlogging that are additionally affected by excess salts must have
exceptional trees. Australia has a number of native species which are well
suited to survive these conditions, produce biomass and utilise excess water,
while restricting or coping with the uptake of over-abundant salts. Most
tolerant Australian species have a range of anatomical, morphological and
physiological attributes to contribute to these adaptive qualities. This
review highlights some of these features and describes various combinations
that are successful. Australia now has a range of genotypes to bring to bear
in the battle to rehabilitate landscapes damaged by disruption of the
soil–salt–water balance. Only by redressing these problems can we
ensure that future generations will have land capable of retaining economic
value and producing potable water.
Karyotypic Studies in Artificial Hybrids of Solanum Sections Anarrhichomenum and Basarthrum (Solanaceae)
Authors: Stiefkens Laura , Bernardello Gabriel , Anderson Gregory J.
Published: December 2005

Mitotic chromosomes of seven artificial hybrids fromSolanum L. sect.AnarrichomenumBitter &Basarthrum (Bitter) Bitter were studied(S. caripense Humb. & Bonpl. ex Dunal ×S. basendopogon Bitter,S. caripense × S. muricatumAiton, S. muricatum ×S. basendopogon, S. muricatum× S. caripense,S. muricatum× S. cochoae G.J. Anderson & Bernardello, S. sodiroi Bitter ×S. brevifolium Humb. & Bonpl., andS. sodiroi ×S. caripense).All are wild species except S. muricatum, which is knownonly as a domesticate (‘pepino dulce’). All hybrids were diploidwith 2n = 24. We compare the karyotypes ofparental species and their hybrids to understand chromosome change as acomponent of the evolution of these sections. Statistical analyses ofchromosomes, genome length and centromere position yielded estimates ofkaryotype composition and asymmetry. Comparisons were made by means of ANOVAsand numerical taxonomic methods. Statistical comparisons among the hybridspooled showed much karyotypic similarity among them. Karyotypes of theparental species revealed sharper differences among them. The karyotypes ofthe hybrids except for one combination were not intermediate. In general, thekaryotypes of the hybrids showed relatedness to the karyotype of one parentalspecies. The hybrids involving S. muricatum havechromosomal features closer to it than to the other parental species. Previousstudies showed S. caripense among the wild species to bemost similar to S. muricatum and, as expected, therewere the fewest differences between these species and the hybrids betweenthem. The karyotype of S. sodiroi×S. brevifolium is the most different from the karyotypeof either of its parental species.
Anatomical and morphological studies in the Chenopodiaceae. III. The primary vascular system and nodal anatomy
Authors: Bisalputra T
Published: December 2005

A study of the primary vascular system and nodal anatomy of 32 species of
the family Chenopodiaoeae is reported. The results of other workers are integrated
and hypotheses regarding probable trends in the evolution of the vascular system
are advanced.
Basically, the family has a unilacunar node, and the structure of the primary
vascular system is classified into three types by reference to the number of leaf
traces at a node and their relationships with each other or with cauline bundles
within the axis. The Kochia-Bassia type, which is characteristic of Kochia, Bassia,
Malacocera, Threllceldia, Babbagia, Enchylaena, Suaeda, and Salsola, is the most
primitive and these genera are considered to be closely related. The specialized
articulated group, which includes Salicornia and Arthrocnemum, and the third group,
the Rhagodia-Atriplex, are more advanced. The relationship between genera within
each of these groups is discussed with reference to the vascular anatomy and other
morphological features.
Systematic studies of the anatomy of the Genus Acrotriche R. Br.. 2. The Flower
Authors: Paterson BR
Published: December 2005

The floral anatomy of the 12 species of Acrotriche (Epacridaceae) has been
examined in an effort to determine the extent of specific differences. It was found
that these differences are not as marked as in the leaves. Identification of the species
based on the floral anatomy relies to a large extent on the arrangement of the tissues
in the ovary in conjunction with the presence or absence of hairs. A key to the
species based on the floral anatomy is presented, as well as individual specific
descriptions.
Embryological studies in the compositae. II. Sporogenesis, Gametogenesis, and Embryogeny in Ammobium alatum R. Br.
Authors: Davis GL
Published: December 2005

Ammobium alatum is a perennial herb whose discoid-homogarnous capitula are
surrounded by several rows of involucral bracts with white radiating laminae.
Four microsporangia are present in each anther and their development and
dehiscence are described.
The ovule is anatropous, unitegmic, and tenuinucellate. The archesporial cell
is hypodermal in origin and, following considerable increase in size, it functions directly
as the megaspore mother cell. Cytokinesis and wall formation are postponed until
after Meiosis 11 and a dyad is formed in which each cell is binucleate. The embryo sac
is bisporic and its development is a variation of the Allium type. After fertilization,
the surviving synergid may increase greatly in size but it does not extend into the
micropyle and it collapses when the embryo reaches the seventh cell generation.
Embryogeny is of the Asterad type and the sequence of events leading up to
maturation of the embryo and of the fruit is described.
The ontogeny of the antheriduim in some Leptosporangiate ferns with particular reference to the funnel-shaped wall
Authors: Stone IG
Published: December 2005

An account of the ontogeny of the antheridium including some cytological
details is given for some species of the Blechnaceae and Polypodiaoeae and for
Polyphlebium venosum (R. Br.) Copeland, a member of the Hymenophyllaceae.
In the species of Blechnaceae and Polypodiaceae which were examined the
antheridium consists of three wall cells a discoid or columnar basal cell, a ring cell,
and a cap cell-enclosing the androgonial tissue. The ring cell and cap cell are delimited
by a wall which is laid down in the shape of a funnel.
In Polyphlebium the antheridial wall typically consist's of four cells - a lower
and an upper ring cell, a cap cell, and an operculum. Each ring cell is produced in a
straightforward manner by a funnel-shaped wall.
Davie's postulation concerning the development of the antheridium by a
series of transverse walls and upward and downward expansion of the androgonial
cell, giving the appearance of funnel-shaped walls and ring cells, has been included
in text-books by Smith (1955) and Foster and Gifford (1959).
This hypothesis is questioned, and an explanation of what is considered to be
the true method of development of the funnel-shaped walls and ring cells in the fern
antheridium is given.
Anomalous antheridia of Blechnufm cartilagineum Sw., in which the androgonial
tissue is flattened and abortive, form a deep cap cell and a ring cell separated by a
funnel-shaped wall, although no expansion of the central androgonial cell takes place.
The unusual method by which the pedicel and antheridial initial cell form from
a cell of the filamentous prothallus in Polyphlebium is described.
Are mesic communities less drought-resistant? A study on moisture relationships in dry sclerophyll forest at Inglewood, South Australia
Authors: Martin HA , Specht RL
Published: December 2005

Soil moisture changes under two adjacent forest associations (Eucalyptus
obliqua association in the more mesic environment, E. elaeophora association in the
more xeric sites) were recorded in the Inglewood area of the Mount Lofty Ranges,
South Australia.
The evidence indicated that the E. obliqua association had a higher index of
evapotranspiration (Itr = Etr/Ew0.75) over most of the range of available water (soil
moisture + rainfall) than the E. elaeophora association. The more mesic association
consequently completely exhausted the stored soil moisture during periods of low
rainfall and had to survive a drought period every year.
The other association did not deplete the soil moisture reserves and in an
average year, no drought occurred. Characteristic species of the more mesic association
must be able to survive this drought period especially during the seedling stage.
The status and significance of the hybrid Eucalyptus marginata Sm. × E. megacarpa F.Muell
Authors: Pryor LD , Johnson LAS
Published: December 2005

Blakely's manuscript name Eucalyptus "rivalis" was applied to a specimen
taken from a site about 30 miles south-west of Perth, W.A., where at least two trees
apparently identical with the original specimen are growing at the boundary of areas
occupied by E. marginata and E. megacarpa. On the basis of conditions of occurrence,
morphology, and a progeny test it is considered that E. "rivalis" is a hybrid between
E. marginata and E. megacarpa.
There is morphological evidence that E. megacarpa and the related E. preissiana
have more characters in common with the Renantherae than with any other section
in the genus and that these species were incorrectly placed by Blakely in the Macrantherae,
an error resulting from the use of a single character, anther shape, in determining
affinity. From evidence of morphology and occurrence it is considered that
E. kalganensis and E. chrysantha probably represent hybrids of E. preissiana with
the renantherous species E. marginata and E. sepulcralis respectively, providing
cases parallel with E. "rivalis".
An electron microscope study of the wax bloom on leaves of certain love grasses (Eragrostis curvula (Schrad.) Nees)
Authors: Leigh JH , Matthews JW
Published: December 2005

The bluish leaf colour that is characteristic of certain varieties of Eragrostis
curvula is the result of surface wax extrusions which occur as branched flat ribbons.
Differences in ribbon density exist within and between varieties, and ribbon development
varies with age and light environment. Sections show osmiophilic granules and
streaks in the outer epidermal walls but reveal no pores through which wax might
be extruded.
Estimation of foliage denseness and foliage angle by inclined point quadrats
Authors: Wilson JW
Published: December 2005

The total area of foliage per unit area of land can be estimated from the number
of contacts with foliage made by point quadrats inclined at appropriate angles, and
the distribution of this foiiage area with height above ground be estimated by
recording the heights at which the contacts occur. These estimates, unlike those
based on vertical and horizontal quadrats, are not depressed by variability in foliage
angle (inclination of foliage to the horizontal).
The foliage angle can be estimated by comparing the numbers of contacts
made by quadrats inclined at two different angles, but this estimate is less satisfactory
than one based on vertical and horizontal quadrats. Accurate estimates of both
foliage area and foliage angle can be obtained by using a combination of vertical,
inclined, and horizontal quadrats.
This paper also discusses the application of point quadrat methods to stems
as well as leaves, and considers certain practical aspects of point quadrat use.
Studies on Graminicolous Species of Phyllachora Fckl. I. Ascospores - their liberation and germination
Authors: Parbery DG
Published: December 2005

The process of ascospore liberation is a moderately active one. Discharged
ascospores collect on the host leaf surface in white, glutinous masses and are believed
to be dispersed by rain splash.
Ascospores of all species examined germinated in 2-12 hr at 14°C under
laboratory conditions, but there were indications that the process was more rapid
in the field. The pattern for spore germination and appressorium formation was
similar for the six species studied. Each ascospore produced a single germ tube which,
in 2-6 hr after germination began, formed an appressorium initial in the form of a
swelling at its apex. Appressoria were completely developed 6-12 hr later.
The process of appressorium development is described for species of Phyllachora
for the first time. The swelling at the apex of the germ tube extended back along the
germ tube towards the ascspore. In some species, e.g. P. cornispora, the entire germ
tube was converted into an appressorium which consequently was sessile. In other
species, such as P. parilis, only approximately half of the germ tube developed into
appressorium.
In P. parilis, temperatures greater than 26°C inhibited appressorium formation.
Instead of producing appressoria, germ tubes continued to grow and became long
and flexuous. Germination did not occur at temperatures of 30°C or greater. Evidence
suggested that while contact with a surface was not necessary to initiate appressorium
formation, contact with a grass leaf surface was required for appressoria to develop
normally.
The morphology of appressoria of individual species of Phyllachora was usually
variable when these structures developed in vitro but constant and distinct when they
developed on the host. Among the species examined three basic morphological types
of appressoria were recognized.
Studies on Graminicolous Species of Phyllachora Fckl. II.. Invasion of the host and development of the fungus
Authors: Parbery DG
Published: December 2005

Infection of grasses by species of Phyllachora Fckl. has been observed, and a
detailed examination of the life cycle of two species of this genus has been made on
hosts artificially inoculated while growing under glass-house conditions.
Gemiiiatiiig ascospores of P. ischaemi and P. parilis prodced appressoria on
the leaves of their respective hosts, Ischaemum australe and Paspalurn orbiculare. From
each appressorium an infection peg penetrated into the lumen of an epidermal cell
and expanded into a normal hypha. Some branches of this hypha invaded adjacent
epidermal cells, thus laying the foundations of the clypeus, while other branches
invaded the underlying mesophyll cells. At first all hyphae were intracellular and
passed from cell to cell by means of fine infection hyphae produced by appressorium-like
swellings of the hyphae appressed to the cell wall. Intercellular mycelium was found
at a later stage when hyphae were forming perithecium initials.
The observation that the clypeus developed independently of the perithecium
dispels some existing confusion about its origin. The clypeus developed in the
epidermal cells of the host and not as an outgrowth of the ostiolar region of the
perithecium.
The perithecium initial developed deep in the mesophyll, and in the case of
Phyllachora parilis was preceded by the formation of a subclypeal pycnidium containing
filiform spores. In each case, the perithecium expanded until its ostiolar region came
into close contact with the clypeus. The ostiole then developed right through the
ciypeus, and its development is believed to be lysigenous. The mouth of the ostiole
remained closed by a membrane which appeared to be the undissolved cuticle.
It was noted that asci of all species examined possessed an ascus crown, a
structure not previously observed in species of this genus.
It has been found that the anatomy of the host can determine the form of some
structures of Phyllachora spp. Clypeus thickness is governed by the size of the epidermal
cells, while its radial expansion is checked by the mechanical tissue associated with
vascular bundles. Similarly, perithecium size and shape are influenced by the amount
of mechanical tissue in a leaf.
The time for P. ischaemi to complete its life cycle was influenced by seasonal
conditions. Colonies arising from infections in April 1961 discharged ascospores
in 32 days, whereas infections made 1 month later did not produce sporulating colonies
until 54-58 days later. The full life cycle of P. parilis took 62-77 days when inoculations
were made in May 196 1.
Sporogenesis, Gametogenesis, and embryogeny of Wahlenbergia bicolor N. Lothian
Authors: Want G
Published: December 2005

In Wahlenbergia bicolor, the anther wall is composed of four layers: epidermis,
endothecium, middle layer, and tapetum. Wall formation and microsporogenesis are
described, and the pollen grains are shed at the two-celled condition.
The ovules are tenuinucellate, with a hypodermal archesporial cell which develops
directly as the megaspore mother cell. Megasporogenesis is normal, and a monosporic
eight-nucleate embryo sac of the most common Polygonum type develops from the
chalazal megaspore. The antipodals degenerate before fertilization.
The development of the embryo is of the solanad type. A suspected case of
polyembryony was observed. The endosperm is cellular from its inception, and so
conforms to the Codonopsis type. A micropylar and a chalazal haustoriurn, both
consisting of two uninucleate cells, are formed from the endosperm.
Comparative studies were made with a known but as yet undescribed coastal
species of Wahlenbergia, and no differences were found.