Morphological characteristics observed in the leaf phytoliths of selected Gymnosperms of eastern Australia

2007 ◽  
pp. 73-78
Author(s):  
J. Parr ◽  
L. Watson
Nematology ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 627-653
Author(s):  
Kerrie A. Davies ◽  
Faerlie Bartholomaeus ◽  
Dong Mei Li ◽  
Zeng Qi Zhao ◽  
Weimin Ye ◽  
...  

Summary Ficophagus from collecting trips in eastern Australia, made over 15 years, are summarised and show that species of the genus occurred widely in sycones of Ficus, subgenus Urostigma, section Malvanthera. Two new species (based on morphological differences and molecular sequencing) are described: Ficophagus elizabethae sp. n. from Ficus macrophylla, F. rubiginosa and F. obliqua, and Ficophagus richardi sp. n. from Ficus obliqua; and a morphospecies, Ficophagus Morphospecies malandicus from Ficus obliqua. Ficophagus elizabethae sp. n. is characterised by having the excretory pore (EP) opening from the level of the junction of the conus and shaft of the stylet to that of the knobs, a relatively long procorpus (1.0-2.5 times length of stylet), female tail with an obliquely truncate tail with a hyaline area and a finely to broadly rounded tip which may be mucronate; post-vulval uterine sac (PUS) ca one vulval body diam. (VBD) in length; rose-thorn-shaped spicule with distinct rostrum and prominent condylus; and genital papillae arranged as largest pair adcloacal, second pair posterior to mid-tail length, and third small pair near tail tip; and was collected from Sydney in New South Wales, to Bundaberg in Queensland (QLD). Ficophagus richardi sp. n. is characterised by having the EP opening at the level of the junction of the stylet shaft and conus, a labial cap which is raised around the opening for the stylet; procorpus 0.8-1.7 times length of the stylet, PUS <1 VBD in length, long uterus, and female tail with a V-shaped hyaline area at the bluntly rounded tip; rose-thorn-shaped spicule with a small rostrum and prominent condylus, three pairs genital papillae, first and largest on anterior cloacal lip, second at 70% of tail length measured from cloacal aperture, and third near tip, and was collected from Ban Ban Springs in the south to the Bundaberg region in the mid-north of QLD. In addition, in the absence of pertinent molecular sequences, a morphospecies is described. Ficophagus Morphospecies malandicus is characterised by having the EP opening anterior to the junction of the stylet conus and shaft, procorpus 0.9-2 times length of stylet, a short PUS usually <1 VBD long, short uterus, rose-thorn-shaped spicule with a raised condylus and prominent rostrum, and three pairs of subventral papillae on the tail (one adcloacal, one posterior to mid-tail and one near tail tip); and was collected from the Atherton Tableland, QLD. A table comparing morphological characteristics is provided to help with identification of Ficophagus nematodes from figs of the section Malvanthera in eastern Australia.


1993 ◽  
Vol 41 (2) ◽  
pp. 145 ◽  
Author(s):  
AW Claridge ◽  
AP Robinson ◽  
MT Tanton ◽  
RB Cunningham

The seasonal production of hypogeal fungal sporoearps was monitored over an 18 month period in a catchment of mixed-species euealypt forest in East Gippsland, Vietoria. During the study, sporocarps of one Ascomycete and 25 Basidiomycete species were collected from soil quadrats sampled sequentially around the bases of eucalypt trees- Sporocarps from these species varied in their dimensions and morphological characteristics. Productivity varied from 21 000 sporocarps ha-1 to 181 000 sporocarps ha-1 or 1.8 kg ha-1 to 8.3 kg ha-1 per month. The probability of occurrence of sporocarps was, on average, greater in midslope sites on a sheltered aspect than elsewhere within the catchment. The number of sporocarps produced varied over time, with a major peak in production occurring during May (late-autumn). This peak occurred mainly within gully sites, which supported on average a greater number of sporocarps than ridge or midslope sites, but a lesser weight of sporocarps. The distribution and productivity (probability of occurrence, number and weight) of sporocarps appeared to be associated with some environmental (soil) variables, but not the physical variables (host tree), that we measured. Sporocarps of some species fruited predominantly in ridge and slope habitats, some species fruited mainly in gullies, whereas others apparently showed no preference for fruiting in ridges, slopes and gullies. Thus, in forest catchments subject to land-management practices such as logging and fire, it may be important to retain undisturbed habitat throughout the topographic sequence to conserve a diversity of hypogeal species.


Plant Disease ◽  
2011 ◽  
Vol 95 (7) ◽  
pp. 877-877 ◽  
Author(s):  
G. Polizzi ◽  
D. Aiello ◽  
V. Guarnaccia ◽  
A. Vitale ◽  
G. Perrone ◽  
...  

Philotheca myoporoides (DC.) M.J. Bayly (previously known as Eriostemon myoporoides), commonly called long-leaf waxflower and native to eastern Australia (Rutaceae family), is a hardy compact shrub or small tree occurring in subtropical to cool temperate regions. P. myoporoides is cultivated in Sicily (Italy) for its ornamental appeal. During April of 2010, a widespread wilting was observed on approximately 80% of 2,000 1-year-old, potted long-leaf waxflower plants grown in a commercial nursery near Catania (eastern Sicily, Italy). Internally, symptomatic plants had conspicuous vascular brown discoloration from the crown to the canopy. Diseased crown and stem tissues of 20 plants were surface disinfested for 30 s in 1% NaOCl, rinsed in sterile water, plated on potato dextrose agar (PDA) amended with 100 mg/liter of streptomycin sulfate, and incubated at 25°C. A Fusarium sp. was consistently isolated from affected plant tissues. Colonies with white or light purple aerial mycelia and violet pigmentation on the underside of the cultures developed after 9 days. On carnation leaf agar, 20 single-spore isolates produced microconidia on short monophialides, macroconidia that were three to five septate with a pedicellate base, and solitary and double-celled or aggregate chlamydospores. A PCR assay was conducted on one representative isolate (ITEM 13490) by analyzing sequences of the benA gene (coding β-tubulin protein) and CaM gene (coding calmodulin protein) using the primers reported by O'Donnell et al. (1). The benA gene sequences of ITEM 13490 (GenBank No. FR828825) exhibited an identity of 100% to Fusarium oxysporum f. sp. radicis-lycopersici strain ATCC 52429 (GenBank No. DQ092480). CaM gene sequences of ITEM 13490 (GenBank No. FR828826) exhibited an identity of 99.6% to F. oxysporum strain ITEM 2367 (GenBank No. AJ560774). Morphological characteristics of the 20 isolates, as well as the PCR assay on a representative strain, identified the isolates associated with disease symptoms as F. oxysporum Schlechtend.:Fr. A pathogenicity test was performed by placing two 1-cm2 plugs of PDA from 9-day-old mycelial cultures near the crown on potted, healthy, 2-month-old cuttings of P. myoporoides. Thirty plants were inoculated with strain ITEM 13490 and the same number of plants served as noninoculated controls. All plants were enclosed for 4 days in plastic bags and placed in a growth chamber at 25 ± 1°C. Plants were then moved to a greenhouse where temperatures ranged from 23 to 27°C. First symptoms, which were identical to those observed in the nursery, developed on one plant 15 days after inoculation. Wilting was detected on all plants after 30 days. Control plants remained symptomless. F. oxysporum was successfully reisolated from symptomatic crown and stem tissues and identified as described above, fulfilling Koch's postulates. To our knowledge, this is the first report of F. oxysporum causing disease of P. myoporoides worldwide. Moreover, this pathogen was recently reported in the same nursery on Eremophila sp. (2), confirming the presence of Fusarium wilt as a potential threat to ornamental plant production in this area, and necessitates the innovation and development of disinfection methods for alveolar trays, greenhouses, and various propagation materials to reduce future disease outbreaks. References: (1) K. O'Donnell et al. Mycoscience 41:61, 2000. (2) G. Polizzi et al. Plant Dis 94:1509, 2010.


2019 ◽  
Author(s):  
Fuyang Ke ◽  
Jinling Wang ◽  
Kehe Wang ◽  
Jiujing Xu ◽  
Yong Wang ◽  
...  

Abstract. The ionospheric morphology responses to tropical cyclone passing over eastern Australia, named as DEBBIE in 2017, is investigated using Global Positioning System (GPS) Slant Total Electron Content (STEC), GPS ionospheric scintillation S4 index and ionospheric characteristics by High Frequency (HF) radio. Based on the data analysis in this study, some significant morphological characteristics of ionospheric responses to tropical cyclone Debbie are identified as follows: a) As the GPS satellites PRN01 and PRN11 were passing above typhoon center, their ROTI (Rate of STEC index) is obviously increased. b) The S4 intensity of the GPS ionospheric scintillation is significantly enhanced on March 27, which mostly concentrate around tropical cyclone center and distribute over the region within 18 °S-25 °S. c) The stronger enhancement of f0F1 and f0F2 was observed by High Frequency at Townsville on March 28, when the distance between Townsville and the center of tropical cyclone Debbie was shorter. Regarding the coupling mechanism between the ionospheric disturbance and the tropical cyclone, it is suspected that the electric field perturbations due to turbulent top movement from tropical cyclones might generate ionospheric irregularity and disturbance. To a certain extent, some ionospheric irregularities can further produce bubbles.


2007 ◽  
Vol 47 (7) ◽  
pp. 833 ◽  
Author(s):  
J. F. Ayres ◽  
W. M. Kelman ◽  
L. A. Lane ◽  
B. E. McCorkell

Birdsfoot trefoil (Lotus corniculatus L.) is a perennial pasture legume with adaptive characteristics and agronomic potential for permanent pastures in the high rainfall temperate zone in eastern Australia. Most birdsfoot trefoil cultivars have been developed for high latitude (>40° north or south) locations, and have long photoperiod (>16 h) requirements for flowering. However, at low latitude (28–32°S) in northern New South Wales (NSW), daylength (~14 h on the summer solstice) provides insufficient photoperiod to stimulate flowering and the level of seed-set needed for effective seedling recruitment. As a precursor to breeding, a study was undertaken to characterise a collection of birdsfoot trefoil populations from low latitude origins. Eight cultivars, two breeding lines and 38 accessions were assessed for flowering prolificacy, seed-set, morphological characteristics and seasonal herbage growth at two sites in northern NSW (Glen Innes 29°42′S, Armidale 30°31′S). None of the cultivars expressed reproductive processes with sufficient intensity to provide the level of seed-set necessary for regeneration. However, three accessions consistently flowered strongly at both sites and expressed desirable agronomic characteristics, and a further 10 accessions and the Australian germplasm BLVR5 flowered strongly at least at one of two sites. These populations provide a genetic base for future cultivar development, so that birdsfoot trefoil might become a perennial legume option for northern NSW and other low latitude regions.


Author(s):  
M. J. Kramer ◽  
Alan L. Coykendall

During the almost 50 years since Streptococcus mutans was first suggested as a factor in the etiology of dental caries, a multitude of studies have confirmed the cariogenic potential of this organism. Streptococci have been isolated from human and animal caries on numerous occasions and, with few exceptions, they are not typable by the Lancefield technique but are relatively homogeneous in their biochemical reactions. An analysis of the guanine-cytosine (G-C) composition of the DNA from strains K-1-R, NCTC 10449, and FA-1 by one of us (ALC) revealed significant differences and DNA-DNA reassociation experiments indicated that genetic heterogeneity existed among the three strains. The present electron microscopic study had as its objective the elucidation of any distinguishing morphological characteristics which might further characterize the respective strains.


Author(s):  
N. Savage ◽  
A. Hackett

A cell line, UC1-B, which was derived from Balb/3T3 cells, maintains the same morphological characteristics of the non-transformed parental culture, and shows no evidence of spontaneous virus production. Survey by electron microscopy shows that the cell line consists of spindle-shaped cells with no unusual features and no endogenous virus particles.UC1-B cells respond to Moloney leukemia virus (MLV) infection by a change in morphology and growth pattern which is typical of cells transformed by sarcoma virus. Electron microscopy shows that the cells are now variable in shape (rounded, rhomboid, and spindle), and each cell type has some microvilli. Virtually all (90%) of the cells show virus particles developing at the cell surface and within the cytoplasm. Maturing viruses, typical of the oncogenic viruses, are found along with atypical tubular forms in the same cell.


Author(s):  
Anne F. Bushnell ◽  
Sarah Webster ◽  
Lynn S. Perlmutter

Apoptosis, or programmed cell death, is an important mechanism in development and in diverse disease states. The morphological characteristics of apoptosis were first identified using the electron microscope. Since then, DNA laddering on agarose gels was found to correlate well with apoptotic cell death in cultured cells of dissimilar origins. Recently numerous DNA nick end labeling methods have been developed in an attempt to visualize, at the light microscopic level, the apoptotic cells responsible for DNA laddering.The present studies were designed to compare various tissue processing techniques and staining methods to assess the occurrence of apoptosis in post mortem tissue from Alzheimer's diseased (AD) and control human brains by DNA nick end labeling methods. Three tissue preparation methods and two commercial DNA nick end labeling kits were evaluated: the Apoptag kit from Oncor and the Biotin-21 dUTP 3' end labeling kit from Clontech. The detection methods of the two kits differed in that the Oncor kit used digoxigenin dUTP and anti-digoxigenin-peroxidase and the Clontech used biotinylated dUTP and avidinperoxidase. Both used 3-3' diaminobenzidine (DAB) for final color development.


Author(s):  
Daryl A. Cornish ◽  
George L. Smit

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.


Sign in / Sign up

Export Citation Format

Share Document