Preliminary investigations into the life cycle of Ventruia inaequalis (Cooke) WINT. in South Australia.

1953 ◽  
Vol 4 (4) ◽  
pp. 415 ◽  
Author(s):  
MW Jeffery

Investigation into the possible sources of primary infection by the fungus Ventruia inaequalis (Cooke) Wint. in spring has been carried out. The results present new information on the life cycle of the pathogen under South Australian conditions. Sources of primary infection, such 'as lesions on one-year-old wood or overwintering superficial conidia on the trees, do not appear important. Bud-scale infection of dormant buds has been shown, and its relative importance is discussed. Ascospores are the most important source of primary infection. Their period of discharge extends to a later date than previously reported for South Australia and is considered in relation to leader shoot and late summer spot infection.

1971 ◽  
Vol 11 (49) ◽  
pp. 186 ◽  
Author(s):  
GJ Leach

Thirty lines of lucerne from regions with Mediterranean and temperate climates were grown on a degp and infertile sandy soil in the Upper South East of South Australia. One trial (A) was cut at the frequency usually recommended for lucerne, and the other (B) was cut twice as often. Both trials were sown in spring 1965 in drills 35 cm apart, and were maintained as pure lucerne stands. The yield of dry matter of the tops was measured in Trial A between November 1966 and November 1969, and in trial B for one year from November 1966. The row cover attained by the plants was measured in each year. In trial A, yields rose to maximum values in spring and declined during the summer months to minimal values in autumn. At most harvests there mere significant differences between lines. Mediterranean lines gave good yields in the early phase of the trial, and were the most productive lines through each late summer to winter period. Lines from cool temperate regions, e.g. Rhizoma, gave low initial yields and low winter yields, but gave largest yields in spring 1968. Two Portuguese lines consistently gave high yields : they were the only lines to produce significantly more total dry matter than Hunter River over three years. All lines adequately survived a very dry year (1967), and most plant losses occurred in the final year of the trial. In 1969, six Mediterranean lines showed poor survival, each had less than 50 per cent row cover. Dry matter yields were smaller in trial B. Lines from cool temperate regions maintained 80 per cent row cover throughout and gave the largest yields. Three Mediterranean lines were eliminated after two years of frequent cutting, and the row cover of five other lines was reduced to less than 50 per cent.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Patricia C. Faulkner ◽  
Ruth M. Elsey ◽  
David Hala ◽  
Lene H. Petersen

AbstractAmerican alligators (Alligator mississippiensis) inhabit freshwater wetlands that are vulnerable to salinization caused by anthropogenic alterations to freshwater flow, in addition to storm surges, sea level rise, and droughts. Salinization of coastal freshwater habitats is a growing concern in a changing climate due to increased frequency and intensity of storm surges and drought conditions. This study opportunistically sampled juvenile male and female wild alligators in various salinities each month excluding November, December, and January for one year at Rockefeller Wildlife Refuge in coastal Louisiana. Blood plasma biochemistry parameters including electrolyte levels were subsequently measured. In addition, levels of various renin–angiotensin–aldosterone system hormones, glucocorticoids, androgens, estrogens, and progestogens were analyzed using liquid chromatography and tandem mass spectrometry. Only males were sampled in hyperosmotic environments (> 10‰) during dry conditions in late summer 2018. In juvenile males, plasma Na+, Cl−, and the progestogen 17α,20β-dihydroxypregnenone were significantly and positively correlated with environmental salinity. However, variation in glucocorticoids, androgens, and estrogens were not associated with hypersaline water while sex steroids showed significant seasonal variation. This study demonstrated significant correlation of environmental salinity with electrolyte levels and a sex steroid in wild juvenile alligators, and to our knowledge represents the first measurement of 17α,20β-dihydroxypregnenone in alligators.


1999 ◽  
Vol 21 (2) ◽  
pp. 169 ◽  
Author(s):  
JL Read

The initial effect of two pulses of heavy cattle grazing on chenopod shrubland plants and invertebrates in northern South Australia was assessed in a two year trial. Both plant and invertebrate communities were structured by subhabitats which were defined by edaphic and water-distribution features. The cover of grasses and the dominant shrubs, Atriplex vesicaria and Maireana astrotricha, declined significantly following grazing but only total vegetation cover was significantly lower than controls one year after grazing. Plant species richness was not affected by the grazing pulses. Abundance of ants increased, but the responses of other invertebrates were inconsistent following grazing. Rainfall had a marked effect upon both plant cover and invertebrate abundance. Key words: chenopod shrublands, pulsed cattle grazing, Atriplex vesicaria, invertebrates, bioindicators


2005 ◽  
Vol 37 (5) ◽  
pp. 373-382 ◽  
Author(s):  
William B. SANDERS

The utility of plastic cover slips as a substratum for in situ study of lichen developmental stages is further explored in a neotropical foliicolous lichen community and in a European temperate corticolous community. Twenty-one months after placement in the tropical forest, the cover slips bore foliicolous lichen thalli with several species producing characteristic ascocarps and ascospores, indicating the suitability of the substratum for completion of the life cycle of these lichens. On cover slips placed within the temperate corticolous community, lichen propagules anchored to the substratum with relatively short attachment hyphae but did not develop further within the one year observation period. Intimately intermixed microbial communities of short-celled, mainly pigmented fungi and chlorophyte algae developed upon the transparent substratum. Among the algae, Trebouxia cells, often in groups showing cell division and without associated lichenizing hyphae, were commonly observed. The potential significance of the free-living populations in the life cycle of Trebouxia and in those of Trebouxia-associated lichen fungi is discussed.


1982 ◽  
Vol 47 (2) ◽  
pp. 160-164
Author(s):  
Glenn L. Falkowski ◽  
Arthur M. Guilford ◽  
Jack Sandler

Utilizing airflow therapy, Schwartz (1976) has claimed an 89% success rate with stutterers following treatment and an 83% success rate at one year follow-up. Such claims have yet to be documented in the scientific literature. The purposes of this study were: (a) to investigate the effectiveness of a modified version of airflow therapy; (b) to examine the relative importance of its two main components—passive airflow and elongation of the first vowel spoken. The speech of two adult male stutterers with a lengthy history of stuttering, was assessed with spontaneous speaking and reading tasks. Results indicated marked improvement in both subjects' speech on the reading task was maintained at follow-up 10 weeks later. For spontaneous speech, results were generally weaker and less durable. Effects of the two treatment components were cumulative and did not allow determination of any differential effectiveness between components. Implications of these findings were considered and directions for future research discussed.


2021 ◽  
Vol 5 (4) ◽  
pp. 1-16
Author(s):  
Kalan Braun ◽  
James Ireland ◽  
Jonathan Klaric

TRILITY has developed a production cloud data management solution, KOIOS DatalytiX to provide hybrid machine learning applications and deterministic modelling tools to its operations, asset management, and engineering teams. Two optimiser applications for chemical coagulant prediction and filtration performance were deployed in the Riverland, South Australia at 10 conventional water treatment plants in 2018, to full production in 2019. One year later the impacts on the optimisation behaviour of operations teams, process performance and trihalomethane (THM) reduction outcomes are discussed.


2006 ◽  
Vol 134 (4) ◽  
pp. 297-307 ◽  
Author(s):  
C.M. Martínez ◽  
A.J. Buendía ◽  
J. Sánchez ◽  
N. Ortega ◽  
M.R. Caro ◽  
...  

2021 ◽  
Author(s):  
Elia Ciani ◽  
Kristine von Krogh ◽  
Rasoul Nourizadeh-Lillabadi ◽  
Ian Mayer ◽  
Romain Fontaine ◽  
...  

AbstractMale Atlantic salmon (Salmo salar) display different sexual strategies, maturing either as parr during the freshwater phase (as sneaky spawners), or as post smolts following one or several years at sea. First sexual maturation (puberty) occurs at different times depending on environmental and genetic factors. To improve our knowledge on the timing (age and season) of first sexual maturation in Atlantic salmon male parr, we investigated pubertal activation in second generation farmed salmon from the Norwegian river Figgjo, reared under natural conditions of photoperiod and water temperature. Histological analysis, in combination with morphometric measurements, plasma androgen levels and pituitary gonadotropin gene expression analysis revealed that, as previously reported, some male parr initiated early sexual maturation in spring at one year of age. Interestingly, some male parr were observed to initiate sexual maturation already in autumn, six months after hatching (under-yearlings), much earlier than reported in previous studies. One-year old maturing males showed a low induction in gonadotropin levels, while under-yearling maturing males displayed a significant increase in fshb transcripts as compared to immature fish. Plasma testosterone, detectable also in immature males, increased constantly during testes development, while 11-ketotestosterone, undetectable in immature and early maturing males, increased during more advanced stages of maturation. A mild feminization of the testes (ovotestes) was detected in a subset of samples. This study brings new knowledge on the little investigated field of sexually maturing under-yearlings in Atlantic salmon. This is also the first study comparing the physiology of under-yearling vs one-year old maturing male parr, thus bringing new insights to the remarkable plasticity of Atlantic salmon puberty.


2011 ◽  
pp. 19-28
Author(s):  
Milan Drekic ◽  
Ljubodrag Mihajlovic

One of the insects that feeds on pedunculate oak acorns and reduces its seed yield is Curculio elephas Gyll. The study of Curculio elephas Gyll is necessary because of the severe damages caused by this insect and also owing to its insufficiently investigated biology. The research was conducted in the common oak seed orchard at Banov Brod, forest estate ?Sremska Mitrovica?, and in the entomological laboratory. The adults emerge from the soil chambers from mid July till the beginning of September. The presence of adults, as determined by crown fogging, ranged from the end of July till the beginning of September with the highest number in mid August. After emerging from the soil, females are already fertile with the developed eggs in the ovaries. They start egg laying after 1 to 8 days and they lay from one to seven eggs per day. Egg laying period lasts from 7 to 20 days. Fertility of C. elephas females ranges from 5 to 40 eggs, while their fecundity ranges from 19 to 45 eggs. At the end of the larval stage, larvae bore into the soil and stay there from one to three years. The species hibernates only in the larval stage. C. elephas has a one-year life cycle, while a minor part of the population has a two or three-year life cycle.


2019 ◽  
Vol 15 ◽  
pp. 01030
Author(s):  
E. Adoir ◽  
S. Penavayre ◽  
T. Petitjean ◽  
L. De Rességuier

Viticulture faces two challenges regarding climate change: adapting and mitigating greenhouse gas emissions. Are these two challenges compatible? This is one of the questions to which Adviclim project (Life project, 2014–2019) provided tools and answers. The assessment of greenhouse gas emissions was implemented at the scale of the plot using a life cycle approach: calculating the carbon footprint. This approach makes it possible to take into account the emissions generated during each stage of the life cycle of a product or a service: in this case, the cultivation of one hectare of vine for one year. Carbon footprint was assessed for the 5 pilot sites of the Adviclim project: Saint-Emilion (France), Coteaux du Layon/Samur (France), Geisenheim (Germany), Cotnari (Romania) and Plompton (United Kingdom). An important work for primary data collection regarding observed practices was carried out with a sample of reresentative farms for these 5 sites, and for one to three vintages depending on the site. Beyond the question asked in the project, the calculation of these carbon footprints made it possible to (i) make winegrowers aware of the life cycle approach and the share of direct emissions generated by viticulture, (ii) acquire new references on the technical itineraries and their associated emissions, (iii) improve the adaptation of the methodology for calculating the carbon footprint to viticulture.


Sign in / Sign up

Export Citation Format

Share Document