ORCID Profile
0000-0002-0886-9064
Current Organisation
University of Queensland - Gatton Campus
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In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Engineering Systems Design | Agricultural Economics | Agricultural Biotechnology not elsewhere classified | Applied Economics
Environmentally Sustainable Plant Production not elsewhere classified | Plant Production and Plant Primary Products not elsewhere classified | Economic Growth |
Publisher: Springer Science and Business Media LLC
Date: 2009
DOI: 10.1071/AP09017
Publisher: Springer Science and Business Media LLC
Date: 13-12-2019
Publisher: Elsevier BV
Date: 08-1998
Publisher: CSIRO Publishing
Date: 19-12-2022
DOI: 10.1071/RJ22022
Abstract: Cereus uruguayanus R.Kiesling is a naturalised, non-opuntioid cactus that has formed large and dense infestations at several locations in the northern Australian rangelands. Of the Cactoideae subfamily, it typically grows into a large, spiny, single- or multi-stemmed candelabra-shaped cactus. While not classified as a Weed of National Significance (WONS) in Australia, it is causing increasing concern, with some local governments declaring it under their local laws. Recent research has identified several herbicides that control C. uruguayanus by using a range of techniques, including basal-bark, cut-stump, foliar, and stem injection applications. Of these, stem injection is one of the recommended options where weeds grow among desirable vegetation because the risk of non-target damage is minimised. This study evaluated C. uruguayanus control using a range of encapsulated dry-formulation herbicides from BioHerbicides Australia (BHA Pty Ltd), using their novel stem-implantation system (Injecta®). In May 2018, an experiment was established in central Queensland to compare the efficacy of six encapsulated herbicides (aminopyralid + metsulfuron-methyl, clopyralid, glyphosate, hexazinone, metsulfuron-methyl, triclopyr + picloram) against an untreated control. Glyphosate was the fastest-acting herbicide, followed by aminopyralid + metsulfuron-methyl and metsulfuron-methyl, with triclopyr + picloram much slower to act. Nevertheless, all four herbicides eventually caused high mortality (≥85%). In contrast, clopyralid and hexazinone were ineffective at the applied rates. Future research is recommended to compare the cost effectiveness of this system against other techniques, particularly those used for stem-injection applications.
Publisher: Informa UK Limited
Date: 06-2017
Publisher: Springer Science and Business Media LLC
Date: 2008
DOI: 10.1071/AP08006
Publisher: Wiley
Date: 04-04-2021
DOI: 10.1111/PPA.13371
Abstract: Pestalotiopsis blight and leaf spot in macadamia are caused by species of Pestalotiopsis and Neopestalotiopsis . Conidia produced by these pathogens are mostly dispersed by wind and rain splash and are the primary infecting propagules. Rapid detection and quantification of airborne conidia are essential to determine the seasonal dynamics of inoculum and critical infection periods in macadamia orchards. A quantitative PCR (qPCR) using a new primer pair and a hydrolysis probe was developed to detect and quantify airborne conidia of Pestalotiopsis and Neopestalotiopsis species. The lification efficiency of the qPCR was 96.4% and the assay had a limit of detection of 400 fg of Pestalotiopsis / Neopestalotiopsis gDNA, which corresponds to approximately 10 conidia. The qPCR assay coupled with spore trapping was used to monitor airborne conidia dispersal under field conditions. The results showed that the assay is specific and sensitive for detecting and quantifying Pestalotiopsis / Neopestalotiopsis conidia in macadamia orchards. The detection and quantification of the pathogen inoculum will improve our understanding of disease epidemiology and the ability to manage these diseases in macadamia.
Publisher: MDPI AG
Date: 08-09-2023
Publisher: Informa UK Limited
Date: 03-2017
Publisher: Elsevier BV
Date: 03-2014
Publisher: CSIRO Publishing
Date: 1996
DOI: 10.1071/AR9960651
Abstract: This greenhouse study investigated the effects of the addition of vesicular-arbuscular mycorrhizal (VAM) inoculum (Glomus mosseae [Nicol. & Gerd.] Gerdemann & Trappe and Glomus etunicatum Becker & Gerdemann) on capsicum (Capsicum annuum L. cv. Target), sweet corn (Zea mays L. cv. Snosweet), and tomato (Lycopersicon esculentum Mill. cv. Floradade) grown in a low P sandy loam (6 mg NaHCO3-extractable P/kg) with 5 rates of P (0, 10.3, 30.9, 92.7, or 278 mg P/kg oven-dry soil P1, P2, P3, P4, or P5, respectively) and 2 rates of N (50 or 200 mg N/L in irrigation solution N1 or N2, respectively). The growth periods (from sowing to harvest) for the 3 crops were as follows: 27 August-22 November 1993 for capsicum, 26 August-29 October 1993 for sweet corn, 31 August-22 October 1993 for tomato. For VAM-inoculated capsicum at PI, the dry weight (10.03 g lant) and mean P concentration in the 5 youngest mature leaves (0.14%) were greater (P 0.05) than those for uninoculated plants (0.28 g lant 0.09% P) a high coefficient of variation necessitated the use of log, transformed data to show differences. At low P rates, dry weight of sweet corn (P1, P2) and tomato (P1) plants colonised with VAM did not differ (P 0.05) from uncolonised plants, despite inoculated plants having higher P concentrations in index tissues. At intermediate P rates, dry weights of inoculated plants were lower (P 0.05) than those of uninoculated plants of sweet corn at P3 (81.1 and 102.2 g lant, respectively) and of tomato at both P2 (11.7 and 34.5 g lant, respectively) and P3 (39.6 and 52.1 g lant, respectively). For all 3 crops, a lack of VAM response at high P ( P4) was related to a lower (P 0.05) VAM colonisation. The percentage root length colonised by VAM at P5 was only 6.8, 19.6, and 2.4% of that measured at P1 in the case of capsicum, sweet corn, and tomato roots, respectively. Increasing N concentration in the irrigation solution from 50 to 200 mg/L increased (P 0.05) VAM colonisation of sweet corn (from 28 8 to 36 2%), but had no effect on capsicum and tomato.
Publisher: Wiley
Date: 09-1988
Publisher: MDPI AG
Date: 20-10-2023
DOI: 10.3390/IJPB14040069
Publisher: Springer Science and Business Media LLC
Date: 2006
DOI: 10.1071/AP05093
Publisher: Oxford University Press (OUP)
Date: 09-2022
DOI: 10.1111/JAM.15241
Abstract: Flower blights (grey mould, green mould and dry flower) are important diseases of macadamia. Lack of information on pathogen biology and disease epidemiology in macadamia has h ered control options. Effects of climatic variables including temperature, relative humidity (RH) and vapour pressure deficit (VPD) on the abundance, germination and growth of conidia of four fungal pathogens that cause various flower blights in macadamia were studied. Mycelial growth, sporulation, conidial germination and germ tube growth for five isolates each of Botrytis cinerea, Cladosporium cladosporioides, Pestalotiopsis macadamiae and Neopestalotiopsis macadamiae, at eight temperatures, seven RH and the corresponding VPD regimes were determined in vitro. The optimal climatic range of each of the four pathogens was validated during macadamia flowering periods in the 2019 and 2020 seasons by conidia detected and quantified using quantitative PCR. Several growth models were fitted to the data with high significance predicted optima from these models ranged from 0.9 to 1.1 kPa VPD for P. macadamiae and N. macadamiae and <0.6 kPa VPD for B. cinerea and C. cladosporioides. This study showed that VPD, as a determinant of the fecundity and growth of the four fungal pathogens, was predictive of flower blight incidence in macadamia. The importance of temperature, RH and, thus, VPD for defining the conditions for infection and flower blight epidemics was established. This information provides a firm basis for the development of prediction tools for flower blights in macadamia.
Publisher: CSIRO Publishing
Date: 02-11-2021
DOI: 10.1071/FP21122
Abstract: Resistance of sugarcane (Saccharum officinarum L.) to smut disease (caused by Sporisorium scitamineum) is driven by two separate mechanisms, external and internal resistance. Two progenies generated from an introgression cross, with contrasting responses to smut infection were used to investigate this interaction. Histopathological screening at different stages of the plant growth was used to determine the extent of mycelium growth within sugarcane tissues. Ten disease resistance-related genes were selected, and the relative expression determined using quantitative real-time reverse transcription PCR (real-time RT-qPCR). The results revealed that PR10, HCT1 and ScChi were down-regulated in the susceptible progeny and up-regulated in the resistant progeny early infection process. This may reflect an early attempt to halt pathogen development by increasing the lignin deposition at the infection site. At 8 weeks post-inoculation, they were highly up-regulated in the susceptible progeny coincided with whip development. This reveals a major role for these genes to whip development in the susceptible progeny and indicates that while PR10 is involved in the resistance mechanism of resistant progeny early infection process it also has a role in susceptibility. These results on genetically related progeny with different responses to smut infection reveal a complex interaction of genes and gene networks being induced in response to fungal invasion.
Publisher: Elsevier BV
Date: 04-2017
Publisher: Springer Science and Business Media LLC
Date: 2000
DOI: 10.1071/AP00031
Publisher: MDPI AG
Date: 21-02-2022
Abstract: The temporal progress of Parkinsonia aculeata dieback through a well-established, naturally occurring dieback affected site was monitored using two transects over a seven-year period. This revealed the time and spatial dynamics underlying the nature of this disorder. Assessment of this site demonstrated a decline in in idual plant health over consecutive years, with 98% of parkinsonia plants dying over the study period. Minimal recruitment of new plants led to a collapse in the parkinsonia population. Macrophomina phaseolina (Botryosphaeriaceae) was the only species with known pathogenicity on parkinsonia found in the transect site. This information provides a valuable insight into the timeframe involved in this disease process from infection through to plant death. This is the first research to date to assess the temporal movement of parkinsonia dieback.
Publisher: Elsevier BV
Date: 1988
Publisher: Wiley
Date: 03-1988
Publisher: Springer Science and Business Media LLC
Date: 20-04-2017
Publisher: Scientific Societies
Date: 09-2017
DOI: 10.1094/PHYTO-11-16-0413-R
Abstract: A weather-based simulation model, called Powdery Mildew of Cucurbits Simulation (POMICS), was constructed to predict fungicide application scheduling to manage powdery mildew of cucurbits. The model was developed on the principle that conditions favorable for Podosphaera xanthii, a causal pathogen of this crop disease, generate a number of infection cycles in a single growing season. The model consists of two components that (i) simulate the disease progression of P. xanthii in secondary infection cycles under natural conditions and (ii) predict the disease severity with application of fungicides at any recurrent disease cycles. The underlying environmental factors associated with P. xanthii infection were quantified from laboratory and field studies, and also gathered from literature. The performance of the POMICS model when validated with two datasets of uncontrolled natural infection was good (the mean difference between simulated and observed disease severity on a scale of 0 to 5 was 0.02 and 0.05). In simulations, POMICS was able to predict high- and low-risk disease alerts. Furthermore, the predicted disease severity was responsive to the number of fungicide applications. Such responsiveness indicates that the model has the potential to be used as a tool to guide the scheduling of judicious fungicide applications.
Publisher: Springer Science and Business Media LLC
Date: 2009
DOI: 10.1071/AP09032
Publisher: Springer Science and Business Media LLC
Date: 02-02-2012
Publisher: MDPI AG
Date: 06-02-2022
Abstract: Chinese elm [Celtis sinensis Pers.] is an emerging environmental weed naturalised throughout the coastal and riparian (creek-banks, river margins, and streams) regions of eastern Australia. Throughout this introduced range, its management is limited to the application of synthetic herbicides and mechanical clearing operations (terrain and soil type permitting). The current mechanisms of chemical control (basal bark spraying, stem-injection, and cut-stump applications) often result in collateral damage to non-target native species (such as Eucalyptus spp. and Casuarina cunninghamiana Miq.) through herbicidal drift, runoff or leaching into adjacent habitats. This has raised concerns regarding the suitability of synthetic herbicides in ecologically sensitive (e.g., riparian zones, rainforest margins, and woodlands) or low-value habitats, thereby promoting significant developments in the fields of integrated weed management. This study investigated the effectiveness of a novel stem-implantation system for controlling woody weed species in the context of a conserved habitat. A replicated trial (n = 315) was established among a naturally occurring population of C. sinensis. This trial involved the mapping, measurement, and treatment of this invasive species with five encapsulated synthetic herbicides, as well as an untreated control and benchmark treatment (diesel + AccessTM). A significant effect (p 0.05) on plant vigour and functional canopy was discerned for each assessment period following trial establishment. The highest incidence of mortality was observed among the in iduals treated with glyphosate (245 mg/capsule), aminopyralid and metsulfuron-methyl (58.1 and 37.5 mg/capsule) and picloram (10 mg/capsule), achieving a similar response to the basal bark application of diesel and AccessTM (240 g/L triclopyr, 120 g/L picloram, and 389 g/L liquid hydrocarbon). This was also evidenced by a rapid reduction in functional canopy (i.e., no or little living leaf tissue) from three weeks after treatment. Unlike their industry counterparts, these encapsulated herbicides are immediately sealed into the vascular system of the target species by a plug. This significantly minimises the possibility of environmental or operator exposure to synthetic compounds by providing a targeted, readily calibrated herbicide application.
Publisher: MDPI AG
Date: 14-09-2021
Abstract: An infestation of parkinsonia (Parkinsonia aculeata) located on Alexandria Station, Northern Territory, Australia, was successfully treated with a bioherbicide using stem-implanted capsules. The bioherbicide (Di-Bak Parkinsonia®), containing three endemic endophytic fungi (Lasiodiplodia pseudotheobromae, Macrophomina phaseolina and Neoscytalidium novaehollandiae), is the first Australian registered woody weed bioherbicide. The product was effectively administered to the plant stems using a mechanical device, resulting in the subsequent development of a dieback event. After a period of establishment, it progressed through an adjacent untreated population, resulting in a significant decline in infestation vigour and preventing recruitment from the seedbank. This is the first report of large-scale management of parkinsonia by this method.
Publisher: CSIRO Publishing
Date: 1999
DOI: 10.1071/A97167
Abstract: The growth response of 2 vegetable crops to 5 rates of applied phosphorus (P)in the presence or absence of an existing network of extraradical mycorrhizalmycelium was determined in 2 greenhouse pot experiments (Expt 1, autumnwinter Expt 2, summer autumn) using a low-P growth medium (6 or 5 mgNaHCO3-extractable P/kg for Expt 1 or 2,respectively). In both experiments, capsicum(Capsicum annuum L.) and tomato(Lycopersicon esculentum Mill.) plants were grown at 0(P1 ), 9.2 (P2), 27.5(P3 ), 82.5 (P4 ), or 248(P5) mg P/kg oven-dry soil (spot-placed at sowing)within a nylon mesh (pore size 44 µm). The mesh excluded roots from theoriginal sunflower (Helianthus annuus L.) host plants,to which either live (VAM+) or killed (VAM–) mycorrhizal[Glomus etunicatum Becker & Gerdemann andGlomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe] inoculum was added at sowing. The mesh did allow fungal hyphae togrow into the growth medium contained by the mesh.Whereas VAM+ plants generally had higher P concentrations in indextissues than VAM– plants at low P rates, a concomitant increase in drymatter yield was restricted to the P1 rate. AtP1 in Expt 2, the increase in the dry weight of wholeplants as a result of VAM colonisation was as large as 91.7-fold and 17.9-foldfor capsicum and tomato, respectively. Root starch analysis indicated that thelower dry matter yields of VAM+ plants than of VAM– plants at≥P2 could be attributed to insufficient photosynthateproduction by VAM+ plants to meet the carbon (C) demand of both host andendophytes within the relatively low-light environment of the greenhouse(average daily solar irradiance of 8.4 MJ/m2 forExpt 1 and 13.4 MJ/m2 for Expt 2).The growth response of vegetable crops grown within the greenhouse fromcolonisation by an established mycorrhizal mycelium appears to depend on acritical balance of P and C supply i.e. at P1, P wasmore limiting than C, and the increased uptake of P as a result ofcolonisation of plant roots by VAM resulted in a growth response. At higher Prates, C was more limiting than P due to low light in the greenhouse, and theadditional demand for photosynthate imposed by the endophytes on the hostresulted in a growth depression relative to non-mycorrhizal plants.
Publisher: Springer Science and Business Media LLC
Date: 02-03-2020
Publisher: Springer Science and Business Media LLC
Date: 2002
DOI: 10.1071/AP01077
Publisher: Wiley
Date: 18-02-2023
DOI: 10.1111/PPA.13707
Abstract: Flower diseases threaten macadamia production, but there is a limited understanding of their aetiology. This study was undertaken to establish the ecology of the causal agents in commercial orchards in Australia. Raceme s les at different developmental stages were collected from 42 commercial macadamia orchards during the 2018–2020 flowering seasons. Morphological and molecular phylogenetic analyses of the isolates obtained from the s les with symptoms revealed that 16 fungal species, including two Botrytis spp., six Cladosporium spp., six Neopestalotiopsis spp. and two Pestalotiopsis spp., were associated with the flower blights. Twelve of the fungal species were identified as new records in macadamia. A comparison of the fungal genera showed that Neopestalotiopsis spp. (48%) and Cladosporium spp. (47%) were the most prevalent in the majority of macadamia production regions and were obtained from all four raceme developmental stages. The genus Botrytis was more commonly distributed (16%) in the production areas where humidity was high and was mostly isolated from the mature developmental raceme stages. Based on in planta infection assays under field conditions, the fungal pathogens varied in aggressiveness on macadamia racemes, with B . cinerea , B . macadamiae , C . cladosporioides , C . devikae , N . drenthii , N . macadamiae , N . maddoxii , N . vheenae , P . macadamiae and P . telopeae as the most aggressive and C . angulosum and C . proteacearum as the least aggressive. This study improves our understanding of the aetiology and distribution of the causal agents of flower blight complex in macadamia.
Publisher: CSIRO Publishing
Date: 2002
DOI: 10.1071/AR02029
Abstract: The influences of temperature, time, and moisture on the germination of macroconidia and secondary conidia of Australian isolates of Claviceps africana were studied in vitro. The optimum temperature for germination of both macroconidia and secondary conidia of C. africana was 20°C. Although germination of macroconidia ceased near 31°C, approximately 30% of secondary conidia germinated at 37°C after 48 and 72 h of incubation. Sorghum flower extract agar stimulated macroconidium and secondary conidium germination, irrespective of temperature. Germination of macroconidia and secondary conidia on water agar started after 4 h of incubation at 20°C, reaching a maximum after 16–24 h and 14 h, respectively. Maximum germination of both macroconidia and secondary conidia was at ≥ –5 bars at 20°C. Germination of secondary conidia ceased at –35 bars, whereas macroconidia germinated at water potentials as low as –55 bars at 20°C.
Publisher: MDPI AG
Date: 25-10-2021
DOI: 10.3390/JOF7110898
Abstract: Macadamia (Macadamia integrifolia) is endemic to eastern Australia and produces an edible nut that is widely cultivated in commercial orchards globally. A survey of fungi associated with the grey and green mold symptoms of macadamia flowers found mostly species of Botrytis (Sclerotiniaceae, Leotiomycetes) and Cladosporium (Cladosporiaceae, Dothideomycetes). These isolates included B. cinerea, C. cladosporioides, and unidentified isolates. Amongst the unidentified isolates, one novel species of Botrytis and three novel species of Cladosporium were delimited and characterized by molecular phylogenetic analyses. The new species are Botrytis macadamiae, Cladosporium devikae, C. macadamiae, and C. proteacearum.
Publisher: MDPI AG
Date: 13-08-2021
DOI: 10.20944/PREPRINTS202108.0288.V1
Abstract: An infestation of parkinsonia (Parkinsonia aculeata) located on Alexandria Station, Northern Territory, Australia was successfully treated with a bioherbicide using stem implanted capsules. The bioherbicide containing three endemic endophytic fungi (Lasiodiplodia pseudotheobromae, Macrophomina phaseolina and Neoscytalidium novaehollan-diae) is the first Australian registered woody weed bioherbicide. The product was effectively administered to the plant stems using a mechanical device, resulting in subsequent development of a dieback event, which, after a period of establishment, has moved through the adjacent untreated plant population resulting in significant decline in infestation vigour and reduced recruitment. This is the first report of large-scale management of parkinsonia by this method.
Publisher: CSIRO Publishing
Date: 1999
DOI: 10.1071/A98008
Abstract: This field trial determined the importance of mycorrhizae[Acaulospora mellea Spain & Schenck,Gigaspora margarita Becker & Hall,Glomus clarum Nicolson & Schenck,Glomus etunicatum Becker & Gerdemann, andScutellospora pellucida (Nicol. & Schenck) Walker & Sanders], established from an existing intact network ofvesicular-arbuscular mycorrhizae (VAM) propagules, for production of capsicum(Capsicum annuum L. cv. Target) in a low phosphorus(≤14 mg NaHCO3-extractable P/kg) Typic Paleudalf. The mycorrhizalnetwork was formed previously with sweetcorn (Zea maysL. cv. Snosweet) plants grown in distinct rows. A narrow band of milledsuperphosphate was applied at 0 (P1), 5(P2), 15 (P3), 45(P4), or 135 (P5) kg P/ha toplots that were either fumigated (VAM ) or not fumigated (VAM+).The higher (P 0.05) concentrations of P in theyoungest mature leaf (blade plus petiole) of VAM+ than those of VAMcapsicum plants at P1, P2, andP3 coincided with a greater (P 0.05) weight of marketable fruit of VAM+ than of VAM– plants this finding confirmed the importance of VAM to the enhanced P nutrition ofcapsicum at low P levels. In the non-fumigated soil (1061 non-dormantinfective VAM propagules/g air-dry soil), the inverse sine transformedmeans of percentage colonisation of roots were generally unaffected by Papplication, indicating that addition of P may not reduce VAM colonisation ofroots if the inoculum potential of the soil is high. An alternative hypothesisto account for the relatively undiminished mycorrhizal colonisation ofVAM+ plants at high P rates may relate to a reduction in colonisation forroots growing within the narrow band of applied P, but not for roots growingin the much larger volume of soil outside of this localised P zone. Theabsence of reduced yields and of lower starch concentrations of roots of VAM+ relative to VAM– plants suggested that photosynthateproduction was surplus to the requirements of the plant and fungus for theirradiance encountered during the trial. The gross margin for VAM plants wasmaximal at P5 ($AU3340/ha), and this amountwas similar to the margin for VAM+ plants grown at all treatments exceptP1, which had a lower gross margin. As a substitute forP, mycorrhizae have limited potential in intensive vegetable productionsystems since the cost of P is low compared with total costs. However, otherbenefits of VAM such as decreased susceptibility to disease and improvedstructure of the soil need to be fully assessed to determine the full benefitof mycorrhizae in such systems.
Publisher: Springer Science and Business Media LLC
Date: 10-03-2023
DOI: 10.1007/S10658-023-02664-5
Abstract: Powdery mildew of cucurbits, caused by Podosphaera xanthii , is an economic constraint in cucurbit production worldwide. This study examined the influence of temperature and vapour pressure deficit (VPD) on the rate of conidial germination and the formation of germ tubes in an Australian P. xanthii isolate 12 – 48 h after inoculation. Two experiments were prepared by inoculating cucumber, cv. crystal salad, leaf-discs using a spore settling tower. The first experiment incubated inoculated cucumber leaf-discs at eight temperatures between 8 and 35 °C under saturated vapour pressure (SVP), the second compared 18 VPD conditions between 0.038 and 1.797 kPa, in six humidity chambers (33% – 99% relative humidity) and three temperatures (22 °C, 25 °C, 28 °C). Leaf-discs were cleared, stained and microscopically inspected for conidial germination and the number of germ tubes. The optimal temperature for germination was 28ºC at SVP, where more than 50% of conidia had germinated by 12 h, and 85% by 48 h. Fewer germinated conidia were recorded after 12 h at other temperature treatments between 17 °C and 31 °C. The germination percentage and germination rate were significantly lower when vapour pressure was between 0.13 and 2.5 kPa, with germination in response to VPD varying by approximately 10%, indicating difficulty associating conidial germination to VPD above 0.13 kPa. Germ tube production was highest between 25 ºC and 28 ºC at the lowest VPD treatment at near SVP, with more than 50% of the germinated conidia producing at least three germ tubes. Germination and formation of germ tubes significantly reduced when VPD increased. P. xanthii conidia were able to produce a primary germ tube under relatively dry conditions, such as 2.53 kPa, but these results show infection would be less likely and require longer incubation. This study provides the first crucial step in simulating powdery mildew infections on cucurbit plants and may lead to a model capable of providing risk forecasts or fungicide management decision support tools.
Publisher: Scientific Societies
Date: 05-2006
DOI: 10.1094/PD-90-0539
Abstract: Allowing plant pathology students to tackle fictitious or real crop problems during the course of their formal training not only teaches them the diagnostic process, but also provides for a better understanding of disease etiology. Such a problem-solving approach can also engage, motivate, and enthuse students about plant pathology in general. This paper presents ex les of three problem-based approaches to diagnostic training utilizing freely available software. The first provides an “adventure-game” simulation where students are asked to provide a diagnosis and recommendation after exploring a hypothetical scenario or “case”. Guidance is given on how to create these scenarios. The second approach involves students creating their own scenarios. The third uses a diagnostic template combined with reporting software to both guide and capture students' results and reflections during a real diagnostic assignment.
Publisher: Cambridge University Press (CUP)
Date: 02-08-2021
DOI: 10.1017/WSC.2021.54
Abstract: Sweet acacia [ Vachellia farnesiana (L.) Willd.] is a problematic thorny weed species in several parts of Australia. Knowledge of its seed biology could help to formulate weed management decisions for this and similar species. Experiments were conducted to determine the effect of hot water (scarification), alternating temperatures, light, salt stress, and water stress on seed germination of two populations of V. farnesiana and to evaluate the response of its young seedlings (the most sensitive developmental stage) to commonly available postemergence herbicides in Australia. Both populations responded similarly to all the environmental factors and herbicides therefore, data were pooled over the populations. Seeds immersed in hot water at 90 C for 10 min provided the highest germination (88%), demonstrating physical dormancy in this species. Seeds germinated at a wide range of alternating day/night temperatures from 20/10 C (35%) to 35/25 C (90%), but no seeds germinated at 15/5 C. Germination was not affected by light, suggesting that seeds are nonphotoblastic and can germinate under a plant canopy or when buried in soil. Germination was not affected by sodium chloride (NaCl) concentrations up to 20 mM, and about 50% of seeds could germinate at 160 mM NaCl, suggesting high salt tolerance ability. Germination was only 13% at −0.2 MPa osmotic potential, and no seeds germinated at −0.4 MPa, suggesting that V. farnesiana seeds may remain ungerminated until moisture conditions have become conducive for germination. A number of postemergence herbicides, including 2,4-D + picloram, glufosinate, paraquat, and saflufenacil, provided % control of biomass of young seedlings compared with the non-treated control treatment. Knowledge gained from this study will help to predict the potential spread of V. farnesiana in other areas and help to integrate herbicide use with other management strategies.
Publisher: Informa UK Limited
Date: 22-10-2020
Publisher: Elsevier BV
Date: 12-2003
Publisher: Springer Science and Business Media LLC
Date: 24-10-2019
Publisher: Elsevier BV
Date: 06-1986
Publisher: Wiley
Date: 08-1996
Publisher: MDPI AG
Date: 17-09-2021
DOI: 10.3390/JOF7090771
Abstract: Macadamia (Macadamia integrifolia) is native to eastern Australia and produces an edible nut that is extensively cultivated in commercial orchards in several countries. Little is known about the ersity of fungi associated with diseases of macadamia inflorescences. A survey of fungi associated with the dry flower disease of macadamia detected several isolates of Neopestalotiopsis (Pestalotiopsidaceae, Sordariomycetes). Five new species of Neopestalotiopsis were identified based on molecular phylogenetic analyses of concatenated gene sequences of the internal transcribed spacer (ITS), β-tubulin (TUB), and the translation elongation factor 1-alpha (TEF1α). The new species are named Neopestalotiopsis drenthii, N. maddoxii, N. olumideae, N. vheenae, and N. zakeelii, and are described by molecular, morphological, and cultural characteristics. The ecology of the isolates and their pathogenic, saprophytic, or commensal ability were not determined.
Publisher: Springer Science and Business Media LLC
Date: 14-11-2017
Publisher: Informa UK Limited
Date: 04-2007
Publisher: Wiley
Date: 20-01-2003
Publisher: Springer Science and Business Media LLC
Date: 07-12-2013
Publisher: MDPI AG
Date: 18-11-2021
Abstract: Mimosa bush (Vachellia farnesiana) is an invasive woody weed widely distributed in Australia. While it can be controlled using several mechanical and chemical techniques, this study evaluated a novel herbicide delivery mechanism that minimizes the risk of spray drift and potential non-target damage. This method, developed by Bioherbicides Australia, involves the implantation of encapsulated granular herbicides into the stem of intact plants or into the stump after cutting off plants close to ground level (cut stumps). Trials were implemented near Moree (New South Wales, Australia) on intact (two experimental runs) plants and cut stumped (two experimental runs) plants. For each trial, an untreated control plus the conventional basal bark application of a liquid formulation of triclopyr + picloram mixed with diesel was included for comparison. Encapsulated glyphosate, aminopyralid + metsulfuron-methyl, hexazinone and clopyralid were also tested in all trials. In addition, encapsulated triclopyr + picloram, and metsulfuron-methyl were included in one of the intact plant trials. Aminopyralid + metsulfuron-methyl was consistently most effective on cut stump and intact plants, whilst clopyralid provided highest mortality when applied to cut stumps and single-stemmed intact plants. Particularly for multi-stemmed intact plants, clopyralid should be applied to each stem. Overall, the highest efficacy was achieved on single stemmed plants, but with further refinement of the technique, it should be possible to achieve similar results for multi-stemmed in iduals. This method resulted in a reduction in the use of herbicide and environmental contamination while significantly improving speed of treatment.
Start Date: 10-2019
End Date: 12-2022
Amount: $589,000.00
Funder: Australian Research Council
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