List of Titles

A global review of the invasive aquatic weed Cabomba caroliniana [A. Gray] (Carolina fanwort) : current and future management challenges, and research gaps

- Roberts, Jason, Florentine, Singarayer

Authors: Roberts, Jason , Florentine, Singarayer
Date: 2022
Type: Text , Journal article , Review
Relation: Weed Research Vol. 62, no. 1 (2022), p. 75-84
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Description: Cabomba caroliniana [A. Gray] (Cabombaceae), also known as Carolina fanwort, is a native of South America which has now become a serious invasive threat to aquatic systems across the world. Its capacity to inundate a water column with active fragments and seeds makes the containment and management of C. caroliniana a challenging task and an ecological and economic necessity. Previous and current management efforts have been largely focussed on biological control, drawdown methods, herbicide application, manual removal, shading and the use of a concentrated urea solution. Although these methods have shown some success in reducing large infestations, they are generally considered to be unreliable when used alone since they are unable to contain or reduce the species in the long term with a single-use treatment protocol. It is feared that, without effective, improved and integrated management strategies, C. caroliniana will continue to invade aquatic ecosystems beyond its already wide current distribution, thus causing increased global economic and environmental damage. This review will therefore explore the biology and distribution of C. caroliniana and examine the current and previous attempts for its global management. It will also evaluate the most successful current treatments and clarify where research efforts are urgently needed for the improved long-term extirpation of this aquatic invader. © 2021 European Weed Research Society

A review of the biology, distribution patterns and management of the invasive species Amaranthus palmeri S. Watson (Palmer amaranth) : current and future management challenges

- Roberts, Jason, Florentine, Singarayer

Authors: Roberts, Jason , Florentine, Singarayer
Date: 2022
Type: Text , Journal article , Review
Relation: Weed Research Vol. 62, no. 2 (2022), p. 113-122
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Description: Amaranthus palmeri S. Watson (Palmer amaranth) is an invasive agricultural weed that has quickly risen from a state of relative obscurity to now being globally regarded as one of the most economically destructive and difficult to manage weed species. It is now found in more than 45 countries where it poses a serious threat to agricultural production systems. Amaranthus palmeri is known to aggressively compete against crop plants for resources such as light, space, nutrients and soil moisture, all of which can result in significant crop yield reduction or even lead to crop failure. It has also been reported that A. palmeri is highly prone to evolve herbicide resistance; this makes management exceedingly challenging. Whilst there have been several control approaches introduced to manage the spread and impact of A. palmeri, many of them require more specific and focused research for their successful local and widespread application. In this regard, this global review explores the species’ biology and global distribution patterns, together with previous and current management strategies. It also explores and identifies promising areas of research that still require further investigation to more confidently assist in the control and containment of this globally concerning weed. © 2021 European Weed Research Society.

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Biology, distribution and management of the globally invasive weed Solanum elaeagnifolium Cav (silverleaf nightshade): A global review of current and future management challenges

- Roberts, Jason, Florentine, Singarayer

Authors: Roberts, Jason , Florentine, Singarayer
Date: 2022
Type: Text , Journal article , Review
Relation: Weed Research Vol. 62, no. 6 (2022), p. 393-403
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Description: Solanum elaeagnifolium Cav (silverleaf nightshade) is a deep-rooted, multi-stemmed, perennial, herbaceous woody plant that has been observed to threaten agricultural and native biodiversity worldwide. It is widely agreed that without efficient integrated management, S. elaeagnifolium will continue to cause significant economic and environmental damage across multiple scales. It is estimated that the annual economic impact of S. elaeagnifolium in Australia exceeds AUD $62 million, with this figure likely to be much higher in other countries invaded by this plant. It can also tolerate a high level of abiotic stress and survive in a range of temperatures (below freezing point to 34°C) and areas with an average yearly rainfall between 250 and 600 mm. Its extensive deep taproot system is capable of regenerating asexually and with its many seed dispersal mechanisms; it can quickly spread and establish itself within a region. This makes containment and management of the species especially challenging. Previous management has largely been focused on biological control, competition, essential oils, grazing pressure, herbicide application and manual removal. Despite the large range of available management techniques, there has been little success in the long-term control of S. elaeagnifolium, and only a handful of methods such as essential oils and herbicide application have shown reasonable success for controlling this weed. Therefore, this review aims to synthesise the identified and potentially useful approaches to control S. elaeagnifolium that have been recorded in the literature which deal with its biology, distribution and management. It also explores previous and current management techniques to ascertain the research gaps and knowledge required to assist in the effective and economically sustainable management of this invasive weed. © 2022 The Authors. Weed Research published by John Wiley & Sons Ltd on behalf of European Weed Research Society.

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Effects on photosynthetic response and biomass productivity of acacia longifolia ssp. longifolia under elevated CO2 and water-limited regimes

- Javaid, Muhammad, Wang, Xiukang, Florentine, Singarayer, Ashraf, Muhammad, Mahmood, Athar, Li, Feng-Min, Fiaz, Sajid

Authors: Javaid, Muhammad , Wang, Xiukang , Florentine, Singarayer , Ashraf, Muhammad , Mahmood, Athar , Li, Feng-Min , Fiaz, Sajid
Date: 2022
Type: Text , Journal article
Relation: Frontiers in Plant Science Vol. 13, no. (2022), p.
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Description: It is known that the impact of elevated CO2 (eCO2) will cause differential photosynthetic responses in plants, resulting in varying magnitudes of growth and productivity of competing species. Because of the aggressive invasive nature of Acacia longifolia ssp. longifolia, this study is designed to investigate the effect of eCO2 on gas exchange parameters, water use efficiency, photosystem II (PSII) activities, and growth of this species. Plants of A. longifolia ssp. longifolia were grown at 400 ppm (ambient) and 700 ppm (elevated) CO2 under 100 and 60% field capacity. Leaf gas exchange parameters, water use efficiency, intrinsic water use efficiency, instantaneous carboxylation efficiency, and PSII activity were measured for 10 days at 2-day intervals. eCO2 mitigated the adverse effects of drought conditions on the aforementioned parameters compared to that grown under ambient CO2 (aCO2) conditions. A. longifolia, grown under drought conditions and re-watered at day 8, indicated a partial recovery in most of the parameters measured, suggesting that the recovery of this species under eCO2 will be higher than that with aCO2 concentration. This gave an increase in water use efficiency, which is one of the reasons for the observed enhanced growth of A. longifolia under drought stress. Thus, eCO2 will allow to adopt this species in the new environment, even under severe climatic conditions, and foreshadow its likelihood of invasion into new areas. Copyright © 2022 Javaid, Wang, Florentine, Ashraf, Mahmood, Li and Fiaz.

Efficacy of halosulfuron-methyl in the management of Navua sedge (Cyperus aromaticus) : differential responses of plants with and without established rhizomes

- Chadha, Aakansha, Florentine, Singarayer, Dhileepan, Kunjithapatham, Turville, Christopher, Dowling, Kim

Authors: Chadha, Aakansha , Florentine, Singarayer , Dhileepan, Kunjithapatham , Turville, Christopher , Dowling, Kim
Date: 2022
Type: Text , Journal article
Relation: Weed Technology Vol. 36, no. 3 (2022), p. 397-402
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Description: Navua sedge is a creeping perennial sedge commonly found in tropical environments and is currently threatening many agroecosystems and ecosystems in Pacific Island countries and northern Queensland, Australia. Pasture and crop productions have been significantly impacted by this weed. The efficacy of halosulfuron-methyl on Navua sedge plants with and without well-established rhizomes was evaluated under glasshouse conditions. Halosulfuron-methyl was applied to plants with established rhizomes at three stages; mowed, pre-flowering, and flowering growth stages, whereas plants without established rhizomes were treated at seedling, pre-flowering and flowering growth stages. At each application time, halosulfuron-methyl was applied at four dose rates of 0, 38, 75, and 150 g ai ha-1. Mortality of 27.5%, 0%, and 5% was recorded in rhizomatous Navua sedge when treated with 75 g ai ha-1 of halosulfuron-methyl at the mowed, pre-flowering stage and flowering stages, respectively. At 10 wk after treatment (WAT), there were no tillers in surviving plants treated at any of the application times. By 16 WAT, the number of tillers increased to 15, 24, and 26 in mowed, pre-flowering, and flowering stages, respectively. Although halosulfuron-methyl is effective in controlling aboveground growth, subsequent emergence of new growth from the rhizome confirms the failure of the herbicide to kill the rhizome. Application of 75 g ai ha-1 of halosulfuron-methyl provided 100% mortality in plants treated at seedling and pre-flowering stages, and 98% mortality when treated at flowering stage in non-rhizomatous plants. A single application of halosulfuron-methyl is highly effective at controlling Navua sedge seedlings but not effective at controlling plants with established rhizomes. © 2022 Cambridge University Press. All rights reserved.

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Amaranthus retroflexus L (redroot pigweed) : effects of elevated CO2 and soil moisture on growth and biomass and the effect of radiant heat on seed germination

- Weller, Sandra, Florentine, Singarayer, Welgama, Amali, Chadha, Aakansha, Turville, Christopher

Authors: Weller, Sandra , Florentine, Singarayer , Welgama, Amali , Chadha, Aakansha , Turville, Christopher
Date: 2021
Type: Text , Journal article
Relation: Agronomy Vol. 11, no. 4 (2021), p.
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Description: Amaranthus retroflexus L. (Amaranthaceae), Redroot pigweed, is native to North America, but has become a weed of agriculture worldwide. Previous research into competition with food crops found it significantly reduces yields. Additionally, taxonomy, biomass allocation, physiological responses to light intensity, water stress, elevated CO2, and herbicide resistance have been inves-tigated. To extend other research findings, we investigated growth and biomass yield in response to (i) soil moisture stress, and (ii) drought and elevated CO2. Additionally, we investigated seed germination rates following exposure to three elevated temperatures for two different time periods. Overall, moisture stress reduced plant height, stem diameter, and number of leaves. Elevated CO2 (700 ppm) appeared to reduce negative impacts of drought on biomass productivity. Heating seeds at 120◦C and above for either 180 or 300 s significantly reduced germination rate. These results inform an understanding of potential responses of A. retroflexus to future climate change and will be used to predict future occurrence of this weed. The finding that exposing seeds to high temperatures retards germination suggests fire could be used to prevent seed germination from soil seed banks, particularly in no-till situations, and therefore may be used to address infestations or prevent further spread of this weed. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliates “Sandra Weller, Singarayer Florentine, Amali Welgama, Aakansha Chadha, Chrisopher Turville" are provided in this record**

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Biology, ecology and management of the invasive navua sedge (cyperus aromaticus) : a global review

- Shi, Boyang, Osunkoya, Olusegun, Chadha, Aakansha, Florentine, Singarayer, Dhileepan, Kunjithapatham

Authors: Shi, Boyang , Osunkoya, Olusegun , Chadha, Aakansha , Florentine, Singarayer , Dhileepan, Kunjithapatham
Date: 2021
Type: Text , Journal article , Review
Relation: Plants Vol. 10, no. 9 (2021), p.
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Description: Navua sedge (Cyperus aromaticus (Ridley) Mattf. & Kukenth) is an invasive perennial sedge, native to tropical Africa, which is threatening many natural ecosystems and agroecosystems, especially in northern Queensland, Australia. Crop and pasture production have been impacted by Navua sedge and it is also directly causing reductions in dairy and beef production in affected regions. This review documents the biology, ecology and potential management options to minimise the spread and impact of Navua sedge. The weed reproduces both sexually (seeds) and vegetatively (via underground rhizomes). Its tiny seeds can be spread easily via wind, water, vehicles, farm machinery and animals, whilst the rhizomes assist with establishment of dense stands. The CLIMEX model (which uses distribution and climate data in native and novel ranges) indicates that in Australia, Navua sedge has the potential to spread further within Queensland and into the Northern Territory, New South Wales and Victoria. Several management strategies, including mechanical, chemical and agronomic methods, and their integration will have to be used to minimise agricultural production losses caused by Navua sedge, but most of these methods are currently either ineffective or uneconomical when used alone. Other management approaches, including biological control and mycoherbicides, are currently being explored. We conclude that a better understanding of the interaction of its physiological processes, ecological patterns and genetic diversity across a range of conditions found in the invaded and native habitats will help to contribute to and provide more effective integrated management approaches for Navua sedge. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Biology, ecology, distribution and control of the invasive weed, lactuca serriola l. (wild lettuce) : a global review

- Chadha, Aakansha, Florentine, Singarayer

Authors: Chadha, Aakansha , Florentine, Singarayer
Date: 2021
Type: Text , Journal article , Review
Relation: Plants Vol. 10, no. 10 (2021), p.
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Description: Lactuca serriola L. (wild lettuce) is a highly invasive C3 weed in many countries, including Australia, Canada, and the USA. This weed is a severe threat to agricultural systems, especially in crops grown with reduced or no‐tillage approaches, which commonly include wheat, cereals and pulses. Owing to the vertical orientation of its leaves in the north‐south plane and its root architec-ture, L. serriola can maintain high water use efficiency under drought conditions, giving it the ability to expand its range under a drying climate. Each plant can produce up to 100,000 seeds which have no primary dormancy and form a short‐term seedbank lasting up to three years. Most seedlings emerge in autumn and overwinter as a rosette, with a small flush of emergence in spring depicting staggered germination. Research into control methods for this weed has been performed, and these methods include chemical herbicides applied alone and in combination, the establishment of plant competition, tillage, mowing and bioherbicide. Herbicides can provide effective control when applied in the seedling or rosette stage; however, spring germination is difficult to control, as it skips the rosette stage. Some biotypes are now resistant to ALS inhibitor and synthetic auxins, causing concern regarding using herbicides. A dedicated integrated management plan for 3–4 years is recommended for the control of this troublesome species. This review will explore the biology, ecology, distribution, current control techniques and previous research on this weed, allowing us to make recommendations for its future research and management. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Can optimum solar radiation exposure or supplemented vitamin D intake reduce the severity of COVID-19 symptoms?

- Abraham, Joji, Dowling, Kim, Florentine, Singarayer

Authors: Abraham, Joji , Dowling, Kim , Florentine, Singarayer
Date: 2021
Type: Text , Journal article , Review
Relation: International Journal of Environmental Research and Public Health Vol. 18, no. 2 (2021), p. 1-21
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Description: The foremost mortality-causing symptom associated with COVID-19 is acute respiratory distress syndrome (ARDS). A significant correlation has been identified between the deficiency in vitamin D and the risk of developing ARDS. It has been suggested that if we can reduce or modify ARDS in COVID-19 patients, we may significantly reduce the severity of COVID-19 symptoms and associated mortality rates. The increased mortality of dark-skinned people, who have a reduced UV absorption capacity, may be consistent with diminished vitamin D status. The factors associated with COVID-19 mortality, such as old age, ethnicity, obesity, hypertension, cardiovascular diseases, and diabetes, are all found to be linked with vitamin D deficiency. Based on this review and as a precautionary measure, it is suggested that the adoption of appropriate and safe solar exposure and vitamin D enriched foods and supplements should be considered to reduce the possible severity of COVID-19 symptoms. Safe sun exposure is deemed beneficial globally, specifically in low and middle- income countries, as there is no cost involved. It is also noted that improved solar exposure and vitamin D levels can reduce the impact of other diseases as well, thus assisting in maintaining general human well-being. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Detection of Malleefowl Mounds from Point Cloud Data

- Parvin, Nahida, Awrangjeb, Mohammad, Irvin, Marc, Florentine, Singarayer, Murshed, Manzur, Lu, Guojun

Authors: Parvin, Nahida , Awrangjeb, Mohammad , Irvin, Marc , Florentine, Singarayer , Murshed, Manzur , Lu, Guojun
Date: 2021
Type: Text , Conference paper
Relation: 2021 International Conference on Digital Image Computing: Techniques and Applications, DICTA 2021, Gold Coast, 29 November to 1 December 2021
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Description: Airborne light detection and ranging (LiDAR) data have become cost and time-efficient means for estimating the size of timid fauna populations through the identification of artefacts that evidence their occurrence in a large, hostile geographic area. The unobtrusive detection method helps conservation managers to assess the stability of a population and to design appropriate conservation programs. Here we propose a mound (nest) detection method for Australia's native iconic bird, the Malleefowl, from point cloud data, which can be manipulated to act as a surrogate for population data. Existing detection methods are largely through manual observations, and are therefore not efficient for covering large and remote areas. The proposed mound detection method can identify mound feature based on height and intensity values provided by the point cloud data. Each candidate mound point is initially selected by applying a height threshold utilising the classified ground points and their corresponding digital elevation model (DEM). Then, another threshold based on intensity range derived from ground truth mound area analysis is applied on the extracted initial mound points to find the final candidate mound points. These extracted points are then used to generate a binary mask where the potential mound points are found sparse. To connect those points, a morphological filter is applied on the binary image and found the mound separated from other remaining non-mound objects. To obtain the mound from other non-mound objects, a morphological cleaning operation and a connected component analysis are carried out on the mask. The non-mound objects are removed from the mask utilising the area property of mound derived from the empirical analysis of ground-truth observations. Finally, the effectiveness of the proposed technique is calculated based on ground truth. Although the mound shapes and structures are highly variable in nature, our height and intensity-based mound point extraction method detected 55 % of the ground-truthed mounds. © 2021 IEEE.

Do primary rainforest tree species recruit into passively and actively restored tropical rainforest?

- Pohlman, Catherine, Tng, David, Florentine, Singarayer

Authors: Pohlman, Catherine , Tng, David , Florentine, Singarayer
Date: 2021
Type: Text , Journal article
Relation: Forest Ecology and Management Vol. 496, no. (2021), p.
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Description: Restoring tropical rainforests is becoming increasingly urgent. However, in most restoration plantings it is not possible to include the full suite of species found in the original rainforest. Full recovery of species composition thus depends on the dispersal and recruitment of species that are not planted. In many restoration projects, however, recruitment is dominated by a low diversity of regionally-abundant pioneer species and species with small, easily dispersed seeds. These species are characteristic of secondary rainforest and do not include the far more diverse suite of species characteristic of the original, primary rainforest. Such primary rainforest species are usually more vulnerable to the effects of fragmentation than disturbance-adapted pioneers and thus are of greater conservation concern, as well as being required for the full recovery of many important ecosystem functions. As restoring ecosystem processes is one of the central goals of restoration, this raises the question of which, if any, of the available rainforest restoration methods may be used to promote the recruitment of primary rainforest species. We compared the species composition and functional group composition of recruited trees and shrubs in a 25-year-old restoration experiment with those of the originally planted trees, and with nearby primary rainforest and secondary rainforest reference sites in an area of upland rainforest in north-eastern Australia. Our objective was to compare the performance of four commonly-used restoration methods: (i) unassisted (passive) regeneration, (ii) Pioneer Monoculture plantings, (iii) Framework Method plantings, and (iv) Maximum Diversity plantings. The species composition and functional group composition of recruited individuals within all treatments were similar to those of secondary rainforest and highly dissimilar to both primary rainforest and plantations. Pioneer species, species with small, biotically-dispersed diaspores, and canopy trees were over-represented among both recruited individuals and in secondary rainforest. Conversely, climax species, species with large, biotically-dispersed diaspores, species with abiotically-dispersed diaspores, and understorey trees were under-represented among both recruited individuals and secondary rainforest. Restoration treatments had little effect on the species or functional group composition of recruited individuals. Our results indicate that species from nearby primary rainforest almost completely failed to recruit into any of the restoration treatments. We argue that this failure was most likely due to the absence of frugivores able to disperse larger diaspores from both secondary forest and restored forest in our study site. Further direct management intervention will be required to restore primary rainforest plant species to restored forests in this region. © 2021 Elsevier B.V.

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Does climate play any role in covid-19 spreading? : an Australian perspective

- Abraham, Joji, Turville, Christopher, Dowling, Kim, Florentine, Singarayer

Authors: Abraham, Joji , Turville, Christopher , Dowling, Kim , Florentine, Singarayer
Date: 2021
Type: Text , Journal article
Relation: International Journal of Environmental Research and Public Health Vol. 18, no. 17 (2021), p.
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Description: Compared to other countries, the COVID-19 pandemic did not severely affect Australia as measured by total deaths until mid-2021. Though a substantial number of daily confirmed cases (up to 698) were reported during the second wave, most of them were from the southern state of Victoria. This study examined the possible correlations between climate variables and the number of daily confirmed COVID-19 cases in Victoria, Australia, from 25 January to 31 October 2020. Appropriate regression models and cross-correlation diagnostics were used to examine the effect of temperature, rainfall, solar exposure, and ultraviolet index (UVI) with the number of daily confirmed cases. Significant positive associations were identified for solar exposure and maximum and average UVI for confirmed cases one and 19 days later. Negative associations for these variables were found for confirmed cases five days later. Minimum temperature had a significant negative correlation one day later and a positive effect 21 days later. No significant correlation was found for maximum temperature and rainfall. The most significant relationships were found for confirmed cases 19 days after changes in the meteorological variables. A 1% increase in solar exposure, maximum UVI, and average UVI was associated with a 0.31% (95% CI: 0.13 to 0.51), 0.71% (95% CI: 0.43 to 0.98), and 0.63% (95%CI: 0.20 to 1.61) increase 19 days later in the number of confirmed cases, respectively. The implications of these results can be used in the public health management of any possible future events in Australia. It also highlights the significance of considering the climatic variables and seasonality in all kinds of epidemics and pandemics. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Erigeron bonariensis, erigeron canadensis, and erigeron sumatrensis

- Florentine, Singarayer, Humphries, Talia, Chauhan, Bhagirath

Authors: Florentine, Singarayer , Humphries, Talia , Chauhan, Bhagirath
Date: 2021
Type: Text , Book chapter
Relation: Biology and Management of Problematic Crop Weed Species, 1st Edition Chapter 7 p. 131-149
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Description: The global human population is expected to reach 8-10 billion by 2050. According to the United Nations, this expansion in population is expected to increase food demands by double the current demand by 2050. Consequently, existing food production systems will come under significant strain. Exacerbating this food production problem is that agronomic weed species across the globe are already causing significant impacts on essential grain yields. Over the past decades, to address weed infestations, farmers have been using range of herbicides. However, overuse of these chemicals has resulted in many weed species mutating to a more resistant form. To implement a successful integrated weed management approach in the future, it will be essential to document the changes in ecology and biology of significant weed species. This chapter focuses on the three most globally significant weeds: Erigeron bonariensis, Erigeron canadensis, and Erigeron sumatrensis, summarizing their current global distribution, seed ecology, impacts, control strategies, as well as current herbicide resistance. These three species are causing significant impacts on important agricultural products including corn, soybean, cotton, wheat, chickpea, sorghum, orchards, and vineyards. Addressing the problem of high levels of herbicide resistance within the Erigeron species has been attempted through various solutions, including novel herbicide mixtures and application timing. Targeting these species in their earlier growth stage with herbicide combinations can greatly improve the success of integrated treatments, broadening the options for suitable approaches such as the use of zero or no-till systems. Given that, these species have innate traits including (1) high seed production, (2) low levels of seed dormancy, (3) high emergence rates, (4) efficient seed dispersal mechanisms, and (5) a highly competitive nature. These advantages, coupled with their ability to withstand a range of climatic conditions and their increasing herbicide-resistant biotypes, make them a serious agricultural weed species across the globe. In this chapter, we have synthesized the characteristic biological features and the effectiveness of various control options. Very limited information is available on the ecology and biology of E. sumatrensis. We have, nevertheless, harvested a significant amount of useful information which may assist farmers to effectively develop integrated agricultural management practices to reduce the impacts of these three species in their productive lands. © 2021 Elsevier Inc. All rights reserved.

Germination biology of four climatically varied populations of the invasive species African lovegrass (Eragrostis curvula)

- Roberts, Jason, Florentine, Singarayer, Van Etten, Eddie, Turville, Christopher

Authors: Roberts, Jason , Florentine, Singarayer , Van Etten, Eddie , Turville, Christopher
Date: 2021
Type: Text , Journal article
Relation: Weed Science Vol. 69, no. 2 (2021), p. 210-218
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Description: African lovegrass [Eragrostis curvula (Schrad.) Nees] is a highly invasive C4 perennial grass that threatens global biodiversity. Appropriate management of this species has been hampered by a lack of knowledge concerning its seed ecology, resulting in significant economic and environmental impacts within various environments. Consequently, this study explored the effects of a selection of environmental factors (photoperiod, alternating temperature, pH, and salinity) by analyzing several measures of germination on four geographically distinct populations of E. curvula to assist in its extirpation from infested sites. Seeds were collected in Australia from Maffra and Shepparton, VIC; Tenterfield, NSW; and Midvale, WA. Key results showed that seeds from Maffra (54% vs. 79%), Tenterfield (38% vs. 61%), and Shepparton (34% vs. 71%) had significantly reduced germination in complete darkness compared with an alternating 12-h light and 12-h dark photoperiod, whereas Midvale had consistent germination (91% vs. 99%). Temperatures between 17/7 C reduced germination for Maffra (42% vs. 73%), Tenterfield (34% vs. 55%), and Shepparton (33% vs. 59%) compared with the mean of all other temperature combinations, whereas Midvale had consistent germination. Furthermore, germination for all populations was consistent between pH 4 and 9. For salinity, germination was significantly reduced at ≥100 mM for Maffra (29% vs. 67%), ≥150 mM for Tenterfield (29% vs. 94%) and Shepparton (39.5% vs. 81.5%), and 250 mM for Midvale (39% vs. 82%) compared with the mean of all other concentrations. Although each trial was conducted independently, the data can be used to generate species-targeted management. Such strategies include maintaining high levels of quarantine and hygiene programs to avoid future spread; where practical, applying light-limiting strategies (mulching, tilling, or scraping) for the Maffra, Tenterfield, and Shepparton populations; and maintaining management efforts year-round, as the species can germinate under a wide range of conditions. © The Author(s), 2021. Published by Cambridge University Press on behalf of the Weed Science Society of America.

Germination biology of three populations of Navua sedge (Cyperus aromaticus)

- Chadha, Aakansha, Florentine, Singarayer, Dhileepan, Kunjithapatham, Dowling, Kim, Turville, Christopher

Authors: Chadha, Aakansha , Florentine, Singarayer , Dhileepan, Kunjithapatham , Dowling, Kim , Turville, Christopher
Date: 2021
Type: Text , Journal article
Relation: Weed Science Vol. 69, no. 1 (2021), p. 69-81
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Description: Navua sedge [Cyperus aromaticus (Ridley) Mattf. & Kük.] is an aggressive perennial sedge native to equatorial Africa that has become problematic in many Pacific islands and wet, tropical Queensland, Australia. It has had a significant impact on the livestock-grazing industry, sugarcane (Saccharum officinarum L.) and banana (Musa acuminata Colla) plantations, and various other ecosystems. A laboratory-based research investigation was conducted to understand germination and emergence requirements under various environmental conditions of three geographically varied populations sourced from South Johnstone (SJ), Mackay (M) and Nyleta Creek (NC) in Queensland. Germination was identified to be stimulated by light, with no germination recorded under darkness. Populations SJ and NC had optimal germination at alternating temperatures of 25/15, 30/20, and 35/25 C, whereas population M had optimal germination at 25/15 and 30/20 C. All populations recorded greater than 85% germination at all pH levels tested. Seeds of population SJ were more sensitive to salinity compared with populations M and NC, with SJ showing no germination at 100 mM, whereas populations M and NC had 23% and 9% germination, respectively. An inverse relationship was observed between osmotic potential and germination, with no germination recorded at osmotic potentials below -0.8 MPa in any population, indicating moisture availability is a critical requirement for germination. Exposing seeds to 120 C radiant heat completely inhibited germination in populations M and NC, whereas 3% of population SJ germinated following a 180-s exposure at 120 C. Seedling emergence decreased as planting depth increased. Emergence was greatest for seeds on the soil surface or at 0.5-cm burial depth, consistent with germination being stimulated by light. Knowledge of these biological characteristics of C. aromaticus seed germination will assist in investigation of suitable control actions for this species, particularly in the early stage of its invasion into new areas, and will contribute to significant reduction in the soil seedbank. © 2021 Cambridge University Press. All rights reserved.

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Licorice (glycyrrhiza glabra) extracts-suitable pharmacological interventions for covid-19? a review

- Abraham, Joji, Florentine, Singarayer

Authors: Abraham, Joji , Florentine, Singarayer
Date: 2021
Type: Text , Journal article , Review
Relation: Plants Vol. 10, no. 12 (2021), p.
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Description: Even though vaccination has started against COVID-19, people should continue maintaining personal and social caution as it takes months or years to get everyone vaccinated, and we are not sure how long the vaccine remains efficacious. In order to contribute to the mitigation of COVID-19 symptoms, the pharmaceutical industry aims to develop antiviral drugs to inhibit the SARS-CoV-2 replication and produce anti-inflammatory medications that will inhibit the acute respiratory distress syndrome (ARDS), which is the primary cause of mortality among the COVID-19 patients. In reference to these tasks, this article considers the properties of a medicinal plant named licorice (Glycyrrhiza glabra), whose phytochemicals have shown both antiviral and anti-inflammatory tendencies through previous studies. All the literature was selected through extensive search in various databases such as google scholar, Scopus, the Web of Science, and PubMed. In addition to the antiviral and anti-inflammatory properties, one of the licorice components has an autophagy-enhancing mechanism that studies have suggested to be necessary for COVID-19 treatment. Based on reviewing relevant professional and historical literature regarding the medicinal properties of licorice, it is suggested that it may be worthwhile to conduct in vitro and in vivo studies, including clinical trials with glycyrrhizic and glycyrrhetinic acids together with other flavonoids found in licorice, as there is the potentiality to provide natural interventions against COVID-19 symptoms. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Medicinal value of three agricultural weed species of the asteraceae family : a review

- Jayasundera, Mithila, Florentine, Singarayer, Tennakoon, Kushan, Chauhan, Bhagirath

Authors: Jayasundera, Mithila , Florentine, Singarayer , Tennakoon, Kushan , Chauhan, Bhagirath
Date: 2021
Type: Text , Journal article , Review
Relation: Pharmacognosy Journal Vol. 13, no. 1 (2021), p. 264-277
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Description: Ageratum conyzoides L., Tridax procumbens L. and Bidens pilosa L. are well known plant species of the Asteraceae family that are considered weeds in intensive agriculture. These weeds are traditionally known to have medicinal properties and have been used for therapeutic treatments. However, it is only the lack of proper knowledge, awareness and screening that have limited their use in pharmaceutical sectors. This review attempts to consolidate the traditional, phytochemical and pharmacological studies that have been carried out on Ageratum conyzoides L., Tridax procumbens L. and Bidens pilosa L., which we note are widely spread throughout the world. This study was conducted through a coherent search on Ageratum conyzoides L., Tridax procumbens L. and Bidens pilosa L. with respect to traditional uses, phytochemical and pharmacological studies that have been performed on these three agricultural weeds all over the world. An exploration of reported descriptions of the potential medical importance of three agricultural weed species (A. conyzoides, T. procumbens and B. pilosa) has been presented. The present review would encourage further clinical investigations into these three plants and their extracts to more closely define the range of uses of these herbs for clinical applications. This, in turn, would give a clear understanding whether these weed species might be targeted to be conserved in a sustainable manner rather than eradicated. © 2021 Phcogj.Com. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.

Reflections on an international nursing placement experience in Nepal : a thematic analysis

- Peel, Rebecca, Missen, Karen, Florentine, Singarayer

Authors: Peel, Rebecca , Missen, Karen , Florentine, Singarayer
Date: 2021
Type: Text , Journal article
Relation: Nurse Education Today Vol. 106, no. (2021), p.
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Description: Background: Increasing patient diversity, as a result of growing global interaction, has necessitated that nursing academics better prepare nursing students to provide culturally appropriate and respectful care to their patients, particularly in culturally diverse countries such as Australia. One approach to improve cultural awareness of nursing students is a cultural immersion placement, and this paper describes such an experience which has been embraced by undergraduate participants. Purpose of this paper was to describe experiences, cultural awareness and challenges encountered by final year undergraduate nursing students undertaking a 22-day cultural immersion placement in Nepal. The researchers accompanied one group of students per year on this trip, which was repeated for three consecutive years. Describing and reflecting on the lived experience of nursing students engaged in this cultural immersion placement has helped to discern how this experience affects the cultural awareness of undergraduate nursing students and helps to decrease the challenges for similar placements in the future. Design and methods: To gain insight into the way this initiative impacted on the development of the participant's cultural competence, a qualitative descriptive design was chosen. Semi-structured interviews were carried out over three consecutive years with final year undergraduate nursing students upon their return from Nepal over three consecutive years. Data analysis followed standard suggestions for a systematic, unbiased approach to dealing with the condensed text, and was analysed using thematic analysis. Results: The findings suggested that this experience, albeit of limited duration, provided a significant contribution to students' understanding of cross-cultural awareness in the context of providing health care. Conclusions: There was a strong implication from the outcomes that this cultural immersion placement should be permanently integrated into the undergraduate nursing course. There was, however, indication that there is room for added reflection and advantages to be made from the experience. © 2021 Elsevier Ltd

Seed longevity and germination in response to changing drought and heat conditions on four populations of the invasive weed African lovegrass (Eragrostis curvula)

- Roberts, Jason, Florentine, Singarayer, Van Etten, Eddie, Turville, Christopher

Authors: Roberts, Jason , Florentine, Singarayer , Van Etten, Eddie , Turville, Christopher
Date: 2021
Type: Text , Journal article
Relation: Weed Science Vol. 69, no. 4 (2021), p. 468-477
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Description: African lovegrass [Eragrostis curvula (Schrad.) Nees] is an invasive weed that is threatening biodiversity around the world and will continue to do so unless its efficient management is achieved. Consequently, laboratory and field-based experiments were performed to analyze several measures of germination to determine the effect of drought stress, radiant heat stress, and burial depth and duration (longevity) on E. curvula seeds. This study investigated seeds from four spatially varied populations across Australia: Maffra and Shepparton, VIC; Tenterfield, NSW; and Midvale, WA. Results showed that increasing drought stress reduced and slowed germination for all populations. Maffra (24% vs. 83%) and Shepparton (41% vs. 74%) were reduced at the osmotic potential of ≤-0.4 MPa, while Tenterfield (35% vs. 98.6%) and Midvale (32% vs. 91%) were reduced at ≤-0.6 MPa, compared with the mean of all other osmotic potentials. Radiant heat at 100 C significantly reduced and slowed germination compared with 40 C for Tenterfield (62% vs. 100%), Shepparton (15% vs. 89%), and Midvale (41% vs. 100%), while Maffra (75% vs. 86%) had consistent germination. For the effect of burial depth and duration (longevity), there was no significant difference across the 14-mo period; however, the 0-cm burial depth had a significantly lower final germination percentage compared with depths of 3, 5, and 10 cm (24% vs. 55%). Although each trial was conducted independently, the results can be used to help identify efficient control measures to reduce infesting populations. Recommended measures include using soil moisture monitoring to detect which conditions will promote germination, as germination is encouraged when the osmotic potential is >-0.6 MPa; exposing seeds to radiant heat (>100 C) using methods such as prescribed burning; and limiting soil disturbance over time to reduce seed establishment. © Authors 2021

Evaluation of the growth response of arid zone invasive species salvia verbenaca cultivars to atmospheric carbon dioxide and soil moisture

- Weller, Sandra, Javaid, Muhammad, Florentine, Singarayer

Authors: Weller, Sandra , Javaid, Muhammad , Florentine, Singarayer
Date: 2020
Type: Text , Journal article
Relation: Rangeland Journal Vol. 42, no. 1 (2020), p. 45-53
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Description: Although climate change is expected to affect the ecology of many weed species, the nature and scale of these responses is presently not well defined. This presages a suite of potential problems for the agricultural industries. Consequently, we investigated the effects of anticipated climate change on biomass and seed production, for two varieties of wild sage, Salvia verbenaca L. var. verbenaca and Salvia verbenaca var. vernalis Bioss. For the investigation, ambient (400 ppm) and elevated (700 ppm) carbon dioxide conditions, in combination with well-watered (100% field capacity) and drought conditions (60% field capacity), were selected to represent alternative climate scenarios. The alteration in biomass production was represented by a combined measurement of nine variables plant height, stem diameter, number of leaves, number of branches, leaf area, leaf thickness, shoot biomass, root biomass and dry leaf weight, and fecundity was measured via two variables 100 seed weight and number of seeds per plant. All biomass measurements were reduced in a drought situation compared with well-watered conditions in ambient carbon dioxide (400 ppm), and each corresponding measurement was greater under elevated carbon dioxide (700 ppm) regardless of water treatment. In contrast, this was not observed for 100 seed weight or number of seeds per plant. Although a similar profile of a reduction in fecundity parameters was observed under drought conditions compared with well-watered conditions in ambient carbon dioxide, there was an increase in seed mass only for var. verbenaca under elevated carbon dioxide in both water treatments. In addition, there was a very small increase in the number of seeds in this species under drought conditions in elevated carbon dioxide, with neither increase in seed mass or seed number being observed in var. vernalis. These results suggest that although future climate change may result in increased competition of both these varieties with desirable plants, their management strategies will need to focus on effects of increased size of the weeds, rather than only attempting to reduce the seed bank holdings. © 2020 Australian Rangeland Society.

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