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Bead-based suspension array systems enable simultaneous fluorescence-based identification of multiple nucleic acid targets in a single reaction. This study describes the development of a novel approach to plant virus and vector diagnostics, a multiplexed 7-plex array that comprises a hierarchical set of assays for the simultaneous detection of begomoviruses and Bemisia tabaci, from both plant and whitefly samples. The multiplexed array incorporates genus, species and strain-specific assays, offering a unique approach for identifying both known and unknown viruses and B. tabaci species. When tested against a large panel of sequence-characterized begomovirus and whitefly samples, the array was shown to be 100% specific to the homologous target. Additionally, the multiplexed array was highly sensitive, efficiently and concurrently determining both virus and whitefly identity from single viruliferous whitefly samples. The detection limit for one assay within the multiplexed array that specifically detects Tomato yellow leaf curl virus-Israel (TYLCV-IL) was quantified as 200fg of TYLCV-IL DNA, directly equivalent to that of TYLCV-specific qPCR. Highly reproducible results were obtained over multiple tests. The flexible multiplexed array described in this study has great potential for use in plant quarantine, biosecurity and disease management programs worldwide., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A semi-automated, immunomagnetic capture-reverse transcription PCR (IMC-RT-PCR) assay for the detection of three pineapple-infecting ampeloviruses, Pineapple mealybug wilt-associated virus-1, -2 and -3, is described. The assay was equivalent in sensitivity but more rapid than conventional immunocapture RT-PCR. The assay can be used either as a one- or two-step RT-PCR and allows detection of the viruses separately or together in a triplex assay from fresh, frozen or freeze-dried pineapple leaf tissue. This IMC-RT-PCR assay could be used for high throughput screening of pineapple planting propagules and could easily be modified for the detection of other RNA viruses in a range of plant species, provided suitable antibodies are available.

Rupert Jethro Best (1903–91), working alone at the Waite Agricultural Research Institute in Adelaide between 1934 and 1937, was among the first to purify tobacco mosaic virus (TMV) and to propose that it was a complex macromolecule containing protein and another reactive group that was responsible for infectivity of the virus. However, his research was completely overshadowed by that of Wendell Stanley and the duo of Frederick Bawden and Norman (aka Bill) Pirie, working in the United States of America and Great Britain, respectively, to the point where Best is not even mentioned in modern histories of TMV. Many factors have contributed to this lack of recognition for Best. Professor James Prescott, a soil scientist and Best's supervisor at the Waite Institute, failed to appreciate the significance of his research, leading to critical delays in publication that prevented him from claiming precedence for purifying TMV. When Best's research was eventually published, it was in Australian journals that were not broadly distributed, resulting in minimal international exposure for his research. The plant virology community within which he worked in Australia was very small and entirely focused on plant disease control, and not concerned with fundamental questions about the composition of viruses. Communication with similarly interested scientists in the Northern Hemisphere was hindered by the great distances involved. In this paper, pioneering research done by Best on TMV is reviewed, and placed in context with that undertaken by Stanley and by Bawden and Pirie, who are best remembered for purifying TMV and characterising its physicochemical properties. Rupert Jethro Best, working alone in Adelaide at the Waite Agricultural Research Institute, was among the first to purify tobacco mosaic virus and to provide evidence that it was a heterogeneous macromolecule, composed mainly of protein but also small prosthetic groups with the properties of a weak acid, wherein lay the activity of the virus. This paper describes the contributions of Rupert Best to early theories on the material nature and mode of reproduction of viruses. Photographer unknown, State Library of South Australia. [ABSTRACT FROM AUTHOR]

This article discusses the history of plant pathology in Australia and its impact on food security. It highlights the challenges faced by Australian farmers, such as extreme weather variability and attacks by pests and pathogens. The article also explores the impact of plant diseases on Indigenous food systems and the importance of genetic diversity in preventing epidemics. It delves into the early history of plant pathology in Australia, including the appointment of the first plant pathologists and the development of training programs. The article acknowledges the flaws in the early plant pathology profession, including gender bias, racial prejudice, and interstate rivalry. It concludes by mentioning the diversity of crops and diseases covered in the special issue and the importance of Australia's plant quarantine system. [Extracted from the article]

Uromycladium tepperianum has been reported on over 100 species of Acacia, as well as on the closely related plant genera, Falcataria, Racosperma and Paraserianthes. Previous studies have indicated that U. tepperianum may represent a complex of host-specific, cryptic species. The phylogenetic relationships between 79 specimens of Uromycladium were determined based on a concatenated dataset of the Small Subunit, the Internal Transcribed Spacer and the Large Subunit regions of nuclear ribosomal DNA, and the mitochondrial cytochrome c oxidase subunit 3. This study showed that the host range of U. tepperianum s.str. was restricted to species of Acacia in the 'A. bivenosa group' sensu Chapman & Maslin (1992). An epitype of U. tepperianum on A. ligulata is designated to create a stable taxonomy for the application of this name. Sixteen novel species of Uromycladium are described, based on host preference, morphology and a phylogenetic species concept. [ABSTRACT FROM AUTHOR]

Efficient and reliable diagnostic tools for the routine indexing and certification of clean propagating material are essential for the management of pospiviroid diseases in horticultural crops. This study describes the development of a true multiplexed diagnostic method for the detection and identification of all nine currently recognized pospiviroid species in one assay using Luminex bead-based suspension array technology. In addition, a new data-driven, statistical method is presented for establishing thresholds for positivity for individual assays within multiplexed arrays. When applied to the multiplexed array data generated in this study, the new method was shown to have better control of false positives and false negative results than two other commonly used approaches for setting thresholds. The 11-plex Luminex MagPlex-TAG pospiviroid array described here has a unique hierarchical assay design, incorporating a near-universal assay in addition to nine species-specific assays, and a co-amplified plant internal control assay for quality assurance purposes. All assays of the multiplexed array were shown to be 100% specific, sensitive and reproducible. The multiplexed array described herein is robust, easy to use, displays unambiguous results and has strong potential for use in routine pospiviroid indexing to improve disease management strategies. [ABSTRACT FROM AUTHOR]