Phytotoxicity and accumulation of PFHxS in Australian native grasses of arid regions: implications for ecological risk assessment.

Nonylphenol polyethoxylates (NPEOs) are a widely used class of nonionic surfactants known to be toxic and endocrine-disrupting contaminants. Their use and production have been banned in the European Union and substituted by other surfactants considered as environmentally safer. However, their use continues in many countries without any legal control. Discharges of effluents from wastewater treatment plants and the application of sewage sludge application, landfilling, and accidental spillage to soils are the major sources of NPEOs in the environment. The biodegradation of these surfactants is relatively easy, leading to the accumulation of the simplest chemical forms of nonylphenol ethoxylates (NP, NP1EO, and NP2EO) and nonylphenol carboxy acids (NP2EC or NP1EC). However, these are also the most toxic end-products and have a higher environmental persistence. Compared to aquatic ecosystems, not much is known about the effects of NPEOs in terrestrial organisms, with few studies mainly centered on the effects on plants and soil microorganisms. The main aim of this study is to provide the range of concentrations of NPEOs with ecotoxicological effects on different plants and soil invertebrate species. In addition, we aim to identify the main soil properties influencing their toxicity. Two natural soils collected and OECD artificial soil were used in toxicity bioassays. Two different NPEO formulations were tested. On the one hand, a technical mixture of NPEOs containing chain isomers and oligomers with an average of eight ethoxy units was used for the experiments and is referred to herein as NP8EO. On the other hand, technical-grade 4-nonylphenol 95% purity was also used and called NP in this study. The chemicals were applied and mixed with soil as an acetone solution. The toxicity of NP8EO and NP was assessed in different taxonomical groups (plants, earthworms, enchytraeids, and collembolans) according to their respective standardized methods. The effect on lethal and sublethal endpoints was assessed and, by means of linear and non-linear regression models, the NPEO concentration causing 10% and 50% inhibition was estimated. The influence of soil properties on the toxicity was assessed using generalized linear models (GLM). The chemicals tested showed contrasting toxicities, NP being clearly more toxic than NP8EO. There were also substantial differences in the sensitivity of the species and endpoints, together with clearly different toxicities in different soils. Plants were the least affected group compared to soil invertebrates, since plant endpoints were unaffected or only slightly inhibited. In soil invertebrates, reproduction was the most affected endpoint compared to growth or survival. Toxicity was the lowest in OECD artificial soil in comparison to natural soils, with a lower organic matter content. The higher toxicity of NP, both in plant and soil invertebrate bioassays, is consistent with previously published studies and its relatively high persistence in soil. The low phytotoxicity of NP8EO and NP, unaffected at concentrations over 1 g NP kg−1, also accords with the known low uptake in plants. The effects on soil invertebrates appeared at lower concentrations than observed in plants, enchytraeids being less affected by NP8EO than earthworms and collembolans. Drastic inhibition in the invertebrate’s endpoints generally appeared over 1 g kg−1 for NP8EO and below 1 g kg−1 for NP. The range of concentrations with effects is in agreement with the few similar studies published to date. Generally, the lowest toxicity values were obtained in OECD soil, with the highest organic matter content, while the highest toxicity was found in the PRA soil, with the lowest content. However, few of the models developed by GLM identified organic carbon as a significant factor in decreasing the bioavailability and toxicity of NPEO. The probable explanation for this is the simultaneous contribution of other soil properties and in particular the limited number of soils used in the bioassays. A low ecotoxicological risk of NPEOs might be expected for plants and soil invertebrates, since the usual concentrations in soils (below 2.6 mg kg−1) are clearly less than the lowest concentrations reported to be toxic in our study. Although the apparent risk of NPEOs for soil ecosystems is limited, such risks should not be neglected since significant concentrations in soil could be reached with elevated application rates or when highly polluted sludges are used. More importantly, NPEO concentrations in soils should be maintained low given the extremely high toxicity for aquatic organisms. Despite the reduced leaching of NPEOs, runoff events might transport NP attached to soil particles and affect adjacent aquatic ecosystems.

Comparisons of metal accumulation and excretion kinetics in earthworms ( Eisenia fetida) exposed to contaminated field and laboratory soils

Floral resources from native plants that are adapted to the local environment could be more advantageous than the use of nonnative plants. In Australia, there is a dearth of information on the benefits of native plants to natural enemies and their selectivity against pests. Accordingly, we examined the longevity of the parasitoids Diaeretiella rapae (McIntosh) and Cotesia glomerata (L.) (both Hymenoptera: Braconidae), and Diadegma semiclausum (Hellen) (Hymenoptera: Ichneumonidae) exposed to flowering shoots from Australian native plants which was compared with the nonnative buckwheat (Fagopyrum esculentum), often used in conservation biological control. Longevity of parasitoids was significantly enhanced by the Australian natives Westringia fruticosa, Mentha satureioides, Callistemon citrinus, Leptospermum cv. ‘Rudolph’, Grevillea cv. ‘Bronze Rambler’, Myoporum parvifolium, Lotus australis, and nonnative F. esculentum. The highest mean survival by native plant species was 3.4× higher for D. rapae with Leptospermum sp. and 4.3× higher for D. semiclausum with M. parvifolium. For C. glomerata, Grevillea sp. increased longevity by 6.9× compared with water only. Longevity of Plutella xylostella (L.) (Lepidoptera: Plutellidae), a major crop pest, was enhanced by all plants against which it was screened except Acacia baileyana, a species that had no effect on parasitoid longevity. Several Australian native plant species that benefit parasitoids were identified. None of the plant species provided a selective benefit to the parasitoid D. semiclausum compared with its host P. xylostella; however, the benefit of M. parvifolium and Grevillea sp. on the longevity of D. semiclausum was relatively higher compared with the pest. These results suggest the need for field studies to determine whether native Australian plants increase P. xylostella impact in nearby brassica crops.

Conservation biological control using Australian native plants in a brassica crop system: seeking complementary ecosystem services

A study of bioactive compounds in selected Australian native plants and products

This research intended to investigate the airborne chemical communication that occurs via volatile substances released by phyllosphere-associated bacteria, and it has been investigated whether it is beneficial to plants. The composition of halotolerant Pseudomonas sp. NEEL19 volatiles and impact on mung bean and fenugreek growth and metabolism were examined through co-culture in PPD. NEEL19 volatile mixtures (NEEL19 V+) enhanced the shoot and root length and chlorophyll content of mung bean under different saline conditions on short-term exposure. In particular, total chlorophyll a + b showed percentage increases of 58.15%, 67.00%, and 29.5% at 0, 50, and 100 mM NaCl, respectively. Furthermore, fenugreek seedlings’ biomass, shoot length, and chlorophyll content significantly increased while exposed to NEEL19 V+. In order to identify the range of volatile organic compounds (VOCs) that NEEL19 released, SPME-GCMS was utilized. The predominant VOC was dimethyl disulfide, while volatile inorganic compounds (VICs), including CO2 and NH3, were examined using the volatile trapping method. Saline stress of 100 mM NaCl influences the quantity and composition of both VOCs and VICs production in NEEL19. The consequences of aqueous NH4OH (1–5 μL) exposure seed PPD assay disclosed that NH3 is one of the responsible volatile substances that trigger substantial alterations in shoot length, root length, total chlorophyll, and stomatal structure in mung bean seedlings. Whereas, fenugreek seedlings exhibited a high chlorophyll content overall. This study indicates that the release of volatile mixtures from NEEL19 promotes the growth and development of mung bean and fenugreek seedlings.

Australian Native Plants: Cultivation and Uses in the Health and Food Industries provides a comprehensive overview of native food crops commercially grown in Australia that possess nutritional and health properties largely unknown on a global basis. These native foods have been consumed traditionally, have a unique flavor diversity, offer significant health promoting effects, and contain useful functional properties. Australian native plant foods have also been identified for their promising antioxidant and antimicrobial properties that have considerable commercial potential. This book is divided into three parts: The first part reviews the cultivation and production of many Australian native plants (ANP), including Anise Myrtle, Bush Tomato, Desert Raisin, Davidson’s Plum, Desert Limes, Australian Finger Lime, Kakadu Plum, Lemon Aspen, Lemon Myrtle, Muntries, Native Pepper, Quandong, Riberry, and Wattle Seed. It then examines the food and health applications of ANP and discusses alternative medicines based on aboriginal traditional knowledge and culture, nutritional characteristics, and bioactive compounds in ANP. In addition, it reviews the anti-obesity and anti-inflammatory properties of ANP and discusses food preservation, antimicrobial activity of ANP, and unique flavors from Australian native plants. The third section covers the commercial applications of ANP. It focuses on native Australian plant extracts and cosmetic applications, processing of native plant foods and ingredients, quality changes during packaging, and storage of Australian native herbs. The final few chapters look into the importance of value chains that connect producers and consumers of native plant foods, new market opportunities for Australian indigenous food plants, and the safety of using native foods as ingredients in the health and food sectors.

Australian Native Plants: Cultivation and Uses in the Health and Food Industries provides a comprehensive overview of native food crops commercially grown in Australia that possess nutritional and health properties largely unknown on a global basis. These native foods have been consumed traditionally, have a unique flavor diversity, offer significant health promoting effects, and contain useful functional properties. Australian native plant foods have also been identified for their promising antioxidant and antimicrobial properties that have considerable commercial potential. This book is divided into three parts: The first part reviews the cultivation and production of many Australian native plants (ANP), including Anise Myrtle, Bush Tomato, Desert Raisin, Davidson’s Plum, Desert Limes, Australian Finger Lime, Kakadu Plum, Lemon Aspen, Lemon Myrtle, Muntries, Native Pepper, Quandong, Riberry, and Wattle Seed. It then examines the food and health applications of ANP and discusses alternative medicines based on aboriginal traditional knowledge and culture, nutritional characteristics, and bioactive compounds in ANP. In addition, it reviews the anti-obesity and anti-inflammatory properties of ANP and discusses food preservation, antimicrobial activity of ANP, and unique flavors from Australian native plants. The third section covers the commercial applications of ANP. It focuses on native Australian plant extracts and cosmetic applications, processing of native plant foods and ingredients, quality changes during packaging, and storage of Australian native herbs. The final few chapters look into the importance of value chains that connect producers and consumers of native plant foods, new market opportunities for Australian indigenous food plants, and the safety of using native foods as ingredients in the health and food sectors.

<p>Soil salinity can result in osmotic and ionic stresses that critically impede seedling emergence, especially in drylands. Novel microbial-based technologies are emerging in the context of ecosystem restoration as a promising strategy to improve seedling establishment in saline environments. However, with recent concerns and the potential adverse impact of the use of exogenous microorganisms as bio-inoculants, much work is needed to develop groups of native microorganisms that can overcome soil salinity stress during restoration. In this study, we tested the effect of bio-inoculants individually composed of halophilic bacteria, biocrust cyanobacteria, and a consortium combination of both, on improving seedling emergence in soils with three salinity levels (low, moderate, and high salinity). Seedling emergence was assessed in four Australian native plants, <em>Triodia epactia, Triodia pungens, Acacia ampliceps </em>and <em>Canavalia rosea,</em> all inoculated with each of the inoculants and a control treatment without microbial inoculation. Our results showed that the highest seedling emergence was recorded in soils with low salinity, followed by moderate salinity soil and high salinity soil. Both <em>Triodia </em>spp. were severely impacted by salinity with very low emergence in all soil types. <em>Acacia</em> sp. emergence was higher when inoculated with halophilic bacteria in low and moderate salinity soils while <em>Canavalia</em> sp. emergence was higher under cyanobacteria inoculation in moderate salinity soils. Overall, our study shows that individual inoculation of halophilic bacteria and cyanobacteria improves the emergence of <em>Acacia </em>sp. and <em>Canavalia </em>sp. seedlings in low and moderate saline soils, while seedling emergence in high salinity soils can only be enhanced when using the combined consortia composed of halophiles and cyanobacteria. The analyses of the soil bacterial community composition by 16S rRNA gene amplicon sequencing showed that the inoculants did not negatively affect the resident bacterial soil communities. In conclusion, poor seedling emergence from salinity stress during the restoration of some plant species can be ameliorated with the inoculation of native halophilic bacteria and cyanobacteria. Grass species such as <em>Triodia</em> might need additional treatments to overcome salinity stress.</p>

Aim: Salinity is a major barrier to successful crop production. Seed priming and exogenous application of different signaling molecules can efficiently confer salinity tolerance. Wheat is a major cereal crop in the world and salinity drastically reduces the wheat seedling growth and yield. Therefore, the present study was conducted to explore the potentiality of different signaling molecules such as salicylic acid (SA) and H2O2 to alleviate the salinity-induced growth inhibition of wheat.
 Place and Duration of the Study: The study was conducted in the Department of Seed Science and Technology, Bangladesh Agricultural University, from September-October, 2021.
 Methodology: The wheat (cv. BARI-Gom 24) seeds were soaked in normal tap water (hydro-priming), 1 mM SA, 2 mM SA, 0.1 mM H2O2, and 0.15 mM H2O2 solutions for 30 minutes. The untreated seeds were used as control. Eventually, primed seeds were exposed to 150 mM NaCl in Petri dishes during germination. Primed and non-primed seedlings were grown for 15 days under 150 mM NaCl stress condition.
 Results: The result revealed that salt stress significantly reduced germination percentage (GP), germination index (GI), seed vigor index (SVI), shoot and root length. The results also exhibited that photosynthetic pigments, total chlorophyll, carotenoids, lycopene, and beta-carotene contents were significantly reduced by salt stress. Seed priming with SA and H2O2 and hydro-priming promoted the germination percentage, seedling growth (including shoot and root length), SVI, and photosynthetic pigments.
 Conclusion: Pretreatment with 1 mM SA and 0.1 mM H2O2 was observed to be relatively more efficient in conferring salinity tolerance of wheat compared with other treating conditions. Overall, this study suggests that wheat seed priming with SA and H2O2 and hydro-priming can improve salinity tolerance.
 Aim: Salinity is a major barrier to successful crop production. Seed priming and exogenous application of different signaling molecules can efficiently confer salinity tolerance. Wheat is a major cereal crop in the world and salinity drastically reduces the wheat seedling growth and yield. Therefore, the present study was conducted to explore the potentiality of different signaling molecules such as salicylic acid (SA) and H2O2 to alleviate the salinity-induced growth inhibition of wheat.
 Place and Duration of the Study: The study was conducted in the Department of Seed Science and Technology, Bangladesh Agricultural University, from September-October, 2021.
 Methodology: The wheat (cv. BARI-Gom 24) seeds were soaked in normal tap water (hydro-priming), 1 mM SA, 2 mM SA, 0.1 mM H2O2, and 0.15 mM H2O2 solutions for 30 minutes. The untreated seeds were used as control. Eventually, primed seeds were exposed to 150 mM NaCl in Petri dishes during germination. Primed and non-primed seedlings were grown for 15 days under 150 mM NaCl stress condition.
 Results: The result revealed that salt stress significantly reduced germination percentage (GP), germination index (GI), seed vigor index (SVI), shoot and root length. The results also exhibited that photosynthetic pigments, total chlorophyll, carotenoids, lycopene, and beta-carotene contents were significantly reduced by salt stress. Seed priming with SA and H2O2 and hydro-priming promoted the germination percentage, seedling growth (including shoot and root length), SVI, and photosynthetic pigments.
 Conclusion: Pretreatment with 1 mM SA and 0.1 mM H2O2 was observed to be relatively more efficient in conferring salinity tolerance of wheat compared with other treating conditions. Overall, this study suggests that wheat seed priming with SA and H2O2 and hydro-priming can improve salinity tolerance.

Cigarette butts (CBs) are emerging soil contaminants, releasing chemicals upon contact with moisture. This study examined heavy metal concentrations leached from smoked and unsmoked CBs (Pall Mall, Philip Morris, and Marlboro) into OECD artificial soil and Vertisol soil and their accumulation in white mustard (Sinapis alba L.). Key physiological parameters, including germination rate, plant height, fresh weight, and dry weight, were analyzed, along with the uptake of heavy metals (Al, Fe, Mn, Zn, Ba, Ti, and Cu) and essential elements (Ca, Mg, Na, and K). Results showed that Mn had the highest bioaccumulation index (BAI = 1.10) in OECD soil, while Zn uptake was consistently high across soil types. Soil type significantly influenced plant height (χ2 = 41.269, p < 0.01) and elemental composition, with Vertisol soil facilitating greater overall growth and heavy metal uptake than OECD soil. MANOVA revealed no three-way interaction among soil type, CB use, and CB brand on elemental uptake. However, two-way interactions, particularly between soil type and CB use (F (4, 39) = 40.233, p < 0.001, Wilk’Λ = 0.195), showed significant effects on heavy metal uptake. These findings highlight the complex interactions influencing plant contamination, underlining the ecological risks of CB pollution in soils.

Human Exposure Estimates for Phthalates

In the present investigation, fungal and bacterial bioagents which were effective against pathogen of bacterial leaf blight disease of rice (Xanthomonas oryzae pv. oryzae) was tested for their effect on germination of rice seeds and growth of nursery seedlings under laboratory and glasshouse conditions. Two isolates of fluorescent pseudomonas isolated from rice phylloplane (Pf 83 and FLP 88), Trichoderma species were isolated from soil of rice field (isolate 40) and Trichoderma harzianum isolated from rice phylloplane. Two commercial formulations (PBA-1 and PBA-2) were tested in the present investigation and compared with chemical treatment (0.76 g Emison + 0.18 g Streptocycline / kg seeds) and untreated check. Under laboratory conditions, chemical treatment was found most effective in increasing seed germination (43.90%) followed by Pf 83 and PBA-1 (34.15 %). Bioagent formulations were significantly effective in increase in root and shoot length as compared to check and chemical treatment. Under glasshouse conditions, maximum increase (29.42%) in seedlings emergence was exhibited by chemical treatment. Maximum increase in root length (100.15%) and shoot length (50.06%) was recorded with FLP 88 and T. harzianum, respectively. Bioagent formulations also increased fresh and dry root weight over check and chemical treatment. All bioagents formulations were effective over chemical treatment and check in increasing fresh shoot weight. Results of the present study revealed that in the absence of pathogen of bacterial leaf blight of rice, fungal and bacterial bioagents significantly enhanced germination of rice seeds and growth of nursery seedlings.

Proponents of importation of the European bumblebee, Bombus terrestris (L.), into Australia for pollination of commercial greenhouse crops argue that this species will have little impact on Australian native ecosystems because it prefers to forage on flowers of introduced species of plants rather than Australian native plants. However, data presented as evidence of preference for introduced plants have been equivocal. This study compared the attractiveness of introduced and Australian native plants to free-foraging B. terrestris in a garden at the interface between an urban area and native vegetation in the Australian island of Tasmania, where a feral population of B. terrestris had been established for over 10 years. No evidence was found to support the proposal that B. terrestris forages on flowers of introduced plants in preference to those of Australian native plants. The numbers of B. terrestris seen foraging per 1000 flowers did not differ significantly between introduced plants and Australian native plants, and the preferred food sources of B. terrestris included flowers of both introduced and Australian native species. Because B. terrestris forages frequently on many species of both introduced and native plants, assessments of its ecological impacts must include the effects of altered pollination on recruitment rates in both introduced weeds and native plants, and reduced quantities of nectar and pollen of native plants on recruitment rates of dependent fauna.

Plastic pollution: Where are we regarding research and risk assessment in support of management and regulation?