This dataset shows the effects of herbicides and one fungicide (detected in Great Barrier Reef catchments) on the specific growth rates (from cell density data) of the microalgae Tisochrysis lutea during laboratory experiments conducted from 2018-2019. The aim of this project was to apply standard ecotoxicology protocols to determine the effects of Photosystem II (PSII), alternative herbicides and one fungicide on the growth of the marine microalgae Tisochrysis lutea. Growth bioassays were performed over 3-day exposures using pesticides that have been detected in the Great Barrier Reef catchment area (O'Brien et al., 2016). These toxicity data will enable improved assessment of the risks posed by PSII and alternative herbicides as well as the fungicide propiconazole to microalgae for both regulatory purposes and for comparison with other taxa. Methods: The haptophyte Tisochrysis lutea (formerly known as Isochrysis galbana)(Grant etal. 2017) (strain CS-177) was purchased from the Australian National Algae Supply Service, Hobart (CSIRO). Cultures of T. lutea were established in EDTA-free Guillard’s f/2 marine medium (Trenfield et al. 2015) (1 ml L-1 of f/2 medium in autoclaved natural seawater). Cultures were maintained in sterile 500 ml Erlenmeyer flasks as batch cultures in exponential growth phase with weekly aseptically transfers of 10 ml T. lutea suspension to 300 ml f/2 medium. Culture were maintained at 28 ± 1°C, 33 ± 1.5 psu and under a 12:12 h light:dark cycle (80 – 100 µmol photons m–2 s–1). Pesticide stock solutions were prepared using PESTANAL (Merck) analytical grade products (purity greater than or equal to 98%): diuron (CAS 330-54-1), metribuzin (CAS 21087-64-9), tebuthiuron (CAS 34014-18-1), bromacil (CAS 314-40-9), propazine (CAS 139-40-2), simazine (122-34-9), imazapic (CAS 104098-48-8), haloxyfop-p-methyl (CAS 72619-32-0), 2,4-D (CAS 94-75-7), MCPA (CAS 94-74-6), fluroxypyr (CAS 69377-81-7) and propiconazole (CAS 60207-90-1). The selection of pesticides was based on application rates and detection in coastal waters of the GBR (Grant et al. 2017, O’Brien et al. 2016). Pesticide stock solutions (100 – 1,000 mg L-1) were prepared by dissolving aliquots of the pure compounds in ultrapure water using clean, acid-washed (5% nitric acid) glass screw-top containers. Simazine, tebuthiuron and haloxyfop-p-methyl were dissolved using the carrier dimethyl sulfoxide (DMSO) (less than or equal to 0.02 % (v/v) in exposure solutions). Diuron, imazapic, metribuzin, bromacil, 2,4-D, propazine, MCPA, fluroxypyr and propiconazole were dissolved in acetone (less than or equal to 0.01 % (v/v) in exposure). Stock solutions were stored refrigerated and in the dark. Tests were conducted as previously described (Trenfield et al. 2015). Cultures of T. lutea were exposed to increasing concentrations of individual pesticides over a period of 72 h. Inoculum was taken from cultures in exponential growth phase (4-d old culture) and starting cell density assessed using a haemocytometer. For each treatment, a total volume of 250 mL test media was prepared in a clean, acid-washed 500 mL Schott bottle. Test media consisted of filtered (0.45 µm) seawater spiked with the respective pesticide stock, quarter strength EDTA-free f/2 media as nutrient source and T. lutea at a starting density of 3x103 or 1x104 cells mL-1. In each toxicity test, the response (specific growth rate of the culture) of the treatments exposed to pesticide were assessed against a seawater control group (no herbicide). For each test, 2 – 3 replicate 125 mL Erlenmeyer flasks (50 mL test volume) were assessed. Flasks were incubated at 27 – 29.0°C under a 12:12 h light:dark cycle (80 – 100 µmol photons m–2 s–1). After 72h, sub-samples (7 ml) were taken from each flask and cell densities measured using a flow cytometer (BD Accuri C6, BD Biosciences, CA, USA). Specific growth rates (SGR) were expressed as the logarithmic increase in cell density from day i (ti) to day j (tj) as per

This dataset shows the effects of herbicides (detected in the Great Barrier Reef catchments) on the growth rates (from stem length and biomass) on the stonewort Ceratophyllum demersum during laboratory experiments conducted in 2019. The aims of this project were to develop and apply standard ecotoxicology protocols to determine the effects of non-PSII herbicides on the growth of the stonewort Ceratophyllum demersum. Growth bioassays were performed over 7-day exposures using herbicides that have been detected in the Great Barrier Reef catchment area (O’Brien et al. 2016). This toxicity data will enable improved assessment of the risks posed by non-PSII herbicides to aquatic macrophytes for both regulatory purposes and for comparison with other taxa. Methods: The stonewort Ceratophyllum demersum was supplied by Watergarden Paradise Aquatic Nursery, Bass Hill, NSW. Cultures were maintained in 500 L outdoor plastic tanks in recirculating dechlorinated tap water, aerated and maintained at ambient outdoor temperature and lighting. Test replicates selected 48 h in advance and acclimated in dechlorinated tap water, 26 ± 2 °C, under a 12:12 hr light:dark cycle (102 ± 9 µmol photons m–2 s–1). Herbicide stock solutions were prepared using PESTANAL (Sigma-Aldrich) analytical grade products (HPLC less than or equal to 98%): haloxyfop-p-methyl (CAS 72619-32-0), imazapic (CAS 104098-48-8) and triclopyr (CAS 5535-06-3). The selection of herbicides was based on application rates and detection in coastal waters of the GBR (Grant et al. 2017, O’Brien et al. 2016). Stock solutions were prepared in 500 mL glass volumetric flasks using milli-Q water. Haloxyfop-p-methyl was dissolved using analytical grade acetone (< 0.01% (v/v) in exposures). Imazapic was dissolved in methanol (less than or equal to 0.01% (v/v) in exposure). No solvent carrier was used for the preparation of triclopyr. Cultures of Ceratophyllum demersum were exposed to a range of herbicide concentrations over a period of 7 days. Plants were sourced from actively growing cultures free of overt disease or deformity. Individual plants approximately 35 mm long with 5 whorls and an apical tip were added to 150 mL of each herbicide solution concentration and control treatment. In each toxicity test, a control (no herbicide) and solvent control (if used) treatments were added to support the validity of the test protocols and to monitor continued performance of the assays. Experiments were conducted in autoclaved, recirculating dechlorinated tap water. Five replicates of each treatment solution and control were prepared and incubated at 26.6 ± 0.5 °C under a 12:12 h light:dark cycle (90 ± 6 µmol photons m–2 s–1). Each replicate treatment was photographed at a standard height to measure stem length at Day 0 and Day 7. Biomass of a representative numbers of fronds were weighed at Day 0 to 3 significant figures using an analytical balance after blotting for 15 seconds to remove excess moisture. Fronds from each treatment replicate were weighed at Day 7 using the same technique. Specific growth rates (SGR) were expressed as the logarithmic increase in stem length (mm) or biomass (g) from day i (ti) to day j (tj) as per equation (1), where SGRi-j is the specific growth rate from time i to j; Xj is the stem length or biomass at day j and Xi is the stem length or biomass at day i (OECD 2006). SGRi-j =[(ln Xj - ln X i) / (tj - ti)] (day-1) (1) SGR relative to the control / solvent control treatment was used to derive chronic effect values for growth inhibition. A test was considered valid, if the SGR for frond number or surface area of control replicates was greater than or equal to 0.0495 day-1 determined from (OECD 2006 and Riethmuller et al 2003). Physical and chemical characteristics of each treatment were measured at 0 and 7 days including pH, electrical conductivity and temperature. Temperature was also logged in 15-min intervals over the total test duration. Analytical samples were taken at

This dataset shows the effects of eight herbicides (detected in Great Barrier Reef catchments) on the specific growth rates (from cell density data) of the microalgae Tetraselmis sp. during laboratory experiments conducted in 2019. The aim of this project was to apply standard ecotoxicology protocols to determine the effects of Photosystem II (PSII) and alternative herbicides on the growth of the marine microalgae Tetraselmis sp. Growth bioassays were performed over 3-day exposures using pesticides that have been detected in the Great Barrier Reef catchment area (O’Brien et al. 2016). These toxicity data will enable improved assessment of the risks posed by PSII and alternative herbicides to microalgae for both regulatory purposes and for comparison with other taxa. Methods: The chlorophyte Tetraselmis sp. (strain CS-317) was purchased from the Australian National Algae Supply Service, Hobart (CSIRO). Cultures of Tetraselmis sp. were established in EDTA-free Guillard’s f/2 marine medium (Guillard and Ryther 1962) (1 ml L-1 of f/2 medium in autoclaved natural seawater). Cultures were maintained in sterile 500 ml Erlenmeyer flasks as batch cultures in exponential growth phase with weekly aseptically transfers of 10 ml Tetraselmis sp. suspension to 300 ml f/2 medium. Culture were maintained at 28 ± 1°C, 33 ± 1.5 psu and under a 12:12 h light:dark cycle (80 – 100 µmol photons m–2 s–1). Pesticide stock solutions were prepared using PESTANAL (Merck) analytical grade products (purity greater than or equal to 98%): diuron (CAS 330-54-1), metribuzin (CAS 21087-64-9), tebuthiuron (CAS 34014-18-1), bromacil (CAS 314-40-9), propazine (CAS 139-40-2), simazine (122-34-9), imazapic (CAS 104098-48-8) and haloxyfop-p-methyl (CAS 72619-32-0). The selection of pesticides was based on application rates and detection in coastal waters of the GBR (Grant et al. 2017, O’Brien et al. 2016). Pesticide stock solutions (100 – 1,000 mg L-1) were prepared by dissolving aliquots of the pure compounds in ultrapure water using clean, acid-washed (5% nitric acid) glass screw-top containers. Simazine, tebuthiuron and haloxyfop-p-methyl were dissolved using the carrier dimethyl sulfoxide (DMSO) (less than or equal to 0.02 % (v/v) in exposure solutions). Diuron, imazapic, metribuzin, bromacil and propazine were dissolved in acetone (less than or equal to 0.01 % (v/v) in exposure). Stock solutions were stored refrigerated and in the dark. Test protocols were based on previously published methods (Trenfield et al. 2015, OECD, 2011). Cultures of Tetraselmis sp were exposed to increasing concentrations of individual pesticides over a period of 72 h. Inoculum was taken from cultures in exponential growth phase (5-d old culture) and starting cell density assessed using a haemocytometer. For each treatment, a total volume of 250 mL test media was prepared in a clean, acid-washed 500 mL Schott bottle. Test media consisted of filtered (0.45 µm) seawater spiked with the respective pesticide stock, quarter strength EDTA-free f/2 media as nutrient source and Tetraselmis sp at a starting density of 2.5x103 cells mL-1. In each toxicity test, the response (specific growth rate of the culture) of the treatments exposed to pesticide were assessed against a seawater control group (no herbicide). For each test, 2 – 3 replicate 125 mL Erlenmeyer flasks (50 mL test volume) were assessed. Flasks were incubated at 27 – 29.0°C under a 12:12 h light:dark cycle (80 – 100 µmol photons m–2 s–1). After 72h, sub-samples (7 ml) were taken from each flask and cell densities measured using a flow cytometer (BD Accuri C6, BD Biosciences, CA, USA). Specific growth rates (SGR) were expressed as the logarithmic increase in cell density from day i (ti) to day j (tj) as per equation (1), where SGRi-j is the specific growth rate from time i to j; Xj is the cell density at day j and Xi is the cell density at day i 6. SGR i-j = [(ln Xj - ln Xi )/(tj - ti )] (day-1) (1) (1) Mean SGR for a pesticide

This dataset shows the measured response of the photosystems of seagrasses to herbicides in experiments conducted in 2014. The purpose of the experiments were to develop and validate a miniature toxicity assay using isolated seagrass leaves in 12-well plate. The aim of this study was to quantify the acute phytotoxicity of PSII herbicide, Diuron, on the seagrass Halophila ovalis while validating a 12-well plate fluorescence bioassay using the imaging pulse amplitude modulation fluorometry. Fluorescence-derived phytotoxicity endpoints in the isolated leaves were directly compared with potted and unpotted but intact (hydroponic) seagrasses and the influence of light on photosynthetic efficiency and damage to PSII were assessed. These data will enable improved assessment of the risks posed by PSII herbicides to tropical seagrass for both regulatory purposes and for comparison with other taxa. Methods: A miniature 12-well plate acute phytotoxicity assay was developed to assess the exposure of seagrass to PSII herbicides:- 1. All acute exposures (up to 24 h) were conducted in static conditions using measured concentrations of Diuron. 2. Pule amplitude modulation (PAM) fluorometry (see below) was applied as a sensitive indicator of PSII herbicide toxicity to isolated seagrass leaves and intact plants. Inhibition of photosynthesis was measured after 24 h exposure using (PAM) fluorometry. Two parameters were measured (effective quantum yield, deltaF/F’m and maximum quantum yield, Fv/Fm). The inhibition of photosynthetic yields relative to controls were plotted as dose-response curves by fitting inhibition data with measured concentrations using a 4-parameter logistic model (SigmaPlot 11). The herbicide inhibition concentrations (ICxx) that inhibited deltaF/Fm' and Fv/Fm by 10 and 50% (IC10 and IC50, respectively) were determined from each curve. 3. Leaves were screened for acceptable levels of photosynthetic efficiency before the start of each experiment. 4. Rapid light curves were used to assess the photosynthetic performance of the seagrass as a function of irradiance and to enable the selection of ambient illumination for the experiments. 5. Fluorescence images were taken using the I-PAM to spatially assess photosynthetic impact of Diuron in the isolated leaves. 6. The photosynthetic condition of plants were re-examined by I-PAM regularly over 24 h in the absence of herbicide to test for leaf deterioration over the exposure period. 7. Dose-response relationships were compared between I-PAM and Mini-PAM data to verify consistency with other studies. 8. Dose-response relationships were compared between isolated leaves in 12-well plates and intact plants (both potted and hydroponic) to validate the sensitivity of the well-plate method. 9. Dose-response relationships were compared using the well plate method at four light levels to (i) test consistency and repeatability under different irradiance conditions and (ii) examine the potential for Diuron to impact on seagrass under varying light conditions. 10. Potential interactions between irradiance and Diuron on effective and maximum quantum yields were explored using the Independent Action (IA) model. Format: Miniature bioassay dataset_Wilkinson_et_al_2014.xlsx: This is the measured response of the photosystem of Halophila ovalis (a seagrass species) to Diuron over time. Plant rep: Plant replicate (3 plants used in each potted and hydroponic tank). Leaf rep: leaf replicate (21 leaves used for solvent control and 9 leaves used per treatment). deltaF/Fm': effective quantum (light adapted) yield measured by a Pulse Amplitude Modulated (PAM) fluorometer. Fv/Fm: maximum quantum (dark adapted) yield measured by a Pulse Amplitude Modulated (PAM) fluorometer. Solvent control: no herbicide but contains less than 0.03% v/v ethanol carrier as per the treatments. Time (hr): duration of exposure in hours (24 h was the duration of the herbicide exposure). PAR: Photosynthetically active radiation

This dataset shows the effects of imazapic (detected in the Great Barrier Reef catchments) on the growth rate (from cell density data) on the cyanobacteria Microcystis aeruginosa over a 72 hour exposure period during laboratory experiments conducted in 2019. The aims of this project were to develop and apply standard ecotoxicology protocols to determine the effects of Photosystem II (PSII) and alternative herbicides on the growth of the cyanobacteria Microcystis aeruginosa. Growth bioassays were performed over 3-day exposures using imazapic which has been detected in the Great Barrier Reef catchment area (O’Brien et al. 2016). This toxicity data will enable improved assessment of the risks posed by the herbicide imazapic to cyanobacteria for both regulatory purposes and for comparison with other taxa. Methods: The cyanobacteria Microcystis aeruginosa (Kutzing) Kutzing 1846 (Cyanophyceae) (CS338/01) was purchased from the Australian National Algae Supply Service, Hobart (CSIRO). Cultures of M. aeruginosa were established in MLA medium (Bolch and Blackburn 1996). Cultures were maintained in sterile 250 mL Erlenmeyer flasks as batch cultures in exponential growth phase with weekly transfers of 1 - 3 mL of a 7 day-old M. aeruginosa suspension to 100 mL MLA medium under sterile conditions. Clean culture solutions were maintained at 26 ± 2°C, and under a 12:12 h light:dark cycle (91 ± 12 µmol photons m–2 s–1). Imazapic stock solution was prepared using PESTANAL (Sigma-Aldrich) analytical grade (HPLC greater than or equal to 98%) imazapic (CAS 104098-48-8). The selection of imazapic was based on application rates and detection in coastal waters of the GBR (Grant et al. 2017, O’Brien et al. 2016). Imazapic stock solution was prepared in 1 L volumetric flasks using milli-Q water. Imazapic was dissolved using analytical grade methanol (final concentration < 0.01% (v/v) in exposures). Cultures of M. aeruginosa were exposed to a range of herbicide concentrations over a period of 72 h. The inoculum was taken from cultures in the exponential growth phase (4 - 7-day-old cultures). A M. aeruginosa working suspension was prepared in a 100 mL volumetric flask. A 1:10 and 1:100 dilution was prepared and counted using a haemocytometer under a compound microscope to determine appropriate dilution volumes. The pre-determined inoculum was added to 50 mL of each test and control treatment replicates to the required dilution (3.1 x 104 cells / mL). A control (no herbicide) and solvent control treatment was added to support the validity of the test protocols and to monitor continued performance of the assays. All treatment concentrations were prepared in 0.5x strength MLA medium. Replicates were incubated at 26.6 ± 0.5 °C under a 12:12 h light:dark cycle (59 ± 9.7 µmol photons m–2 s–1). Sub-samples were taken from each replicate to measure cell densities of algal populations at 72 h using a haemocytometer under phase contrast conditions. Cell counts were done manually. Specific growth rates (SGR) were expressed as the logarithmic increase in cell density from day i (ti) to day j (tj) as per equation (1), where SGRi-j is the specific growth rate from time i to j; Xj is the cell density at day j and Xi is the cell density at day i (OECD 2011). SGR i-j = [(ln Xj - ln Xi )/(tj - ti )] (day-1) (1) SGR relative to the solvent control treatment was used to derive chronic effect values for growth inhibition. A test was considered valid if the SGR of solvent control replicates was ? 0.92 day-1 (OECD 2011). Physical and chemical characteristics (pH, electrical conductivity and temperature) of each treatment solution was measured at 0 hr and 72 hr. Growth cabinet temperature was logged in 15-min intervals over the total test duration. Analytical samples were taken at 0 hr and 72 hr. Mean percent inhibition in SGR of each treatment relative to the control treatment was calculated as per equation (2)(OECD 2011), where Xcontrol is the average SGR of solvent control

This dataset shows the effects of herbicides (detected in the Great Barrier Reef catchments) on growth rates (from surface area and biomass) and photosynthesis (effective quantum yield) on the aquatic fern Azolla pinnata during laboratory experiments conducted in 2019. The aims of this project were to develop and apply standard ecotoxicology protocols to determine the effects of Photosystem II (PSII) and alternative herbicides on the growth and photosynthetic efficiency of the aquatic fern Azolla pinnata. Growth bioassays were performed over 14-day exposures using herbicides that have been detected in the Great Barrier Reef catchment area (O’Brien et al. 2016). Chronic effects of herbicides on the photophysiology of A. pinnata, measured by chlorophyll fluorescence as the effective quantum yield (Delta F/Fm’) were investigated using PAM fluorometry after 14-day herbicide exposure. These toxicity data will enable improved assessment of the risks posed by PSII and alternative herbicides to aquatic macrophytes for both regulatory purposes and for comparison with other taxa. Methods: The aquatic fern Azolla pinnata was sourced from Watergarden Paradise Nursery, NSW. Cultures were established in IRRI2 medium (Pereira & Carrapiço 2009). Cultures were maintained in 10 L tubs containing 3–5 L IRRI2 as batch cultures with weekly transfers to fresh medium. Clean culture solutions were maintained at 26 ± 1 °C, under a 12:12 hr light:dark cycle (65-77µmol photons m–2 s–1). Herbicide stock solutions were prepared using PESTANAL (Sigma-Aldrich) analytical grade products (HPLC greater than or equal to 98%): diuron (CAS 330-54-1), fluometuron (CAS 2164-17-2), fluroxypyr (CAS 69377-81-7), haloxyfop-p-methyl (CAS 72619-32-0), imazapic (CAS 104098-48-8), isoxaflutole (CAS 141112-29-0) and triclopyr (CAS 5535-06-3). The selection of herbicides was based on application rates and detection in coastal waters of the GBR (Grant et al. 2017, O’Brien et al. 2016). Stock solutions were prepared in 100 mL glass volumetric flasks using milli-Q water. Diuron, haloxyfop-p-methyl and isoxaflutole were dissolved using analytical grade acetone (< 0.01% (v/v) in exposures). Imazapic was dissolved in methanol (less than 0.01% (v/v) in exposure). No solvent carrier was used for the preparation of the remaining herbicide stock solutions. Cultures of A. pinnata were exposed to a range of herbicide concentrations over a period of 14 days. Fronds were selected from actively growing cultures free of overt disease or deformity. Four triplicate fronds each comprising eight ramets were added to 100 mL of each herbicide solution concentration and control treatment. In each toxicity test, control (no herbicide) and solvent control (if used) treatments were added to support the validity of the test protocols and to monitor continued performance of the assays. Experiments were conducted in IRRI2 medium (Pereira & Carrapiço 2009) with solutions replaced at Day 7. Three replicates of each treatment solution and control were prepared and incubated at 26.6 ± 0.5 °C under a 12:12 h light:dark cycle (90 ± 6 µmol photons m–2 s–1). Each replicate treatment was photographed at a standard height to estimate surface area at Day 0 and Day 14. Biomass of a representative numbers of fronds were weighed to 4 significant figures using an analytical balance after blotting for 15 seconds to remove excess moisture. Fronds from each treatment replicate were weighed at Day 14 using the same technique. Specific growth rates (SGR) were expressed as the logarithmic increase in surface area or biomass from day i (ti) to day j (tj) as per equation (1), where SGRi-j is the specific growth rate from time i to j; Xj is the surface area or biomass at day j and Xi is the surface area or biomass at day i (OECD 2006). SGR i-j = [(ln Xj - ln Xi )/(tj - ti )] (day-1) SGR relative to the control / solvent control treatment was used to derive chronic effect values for growth inhibition. A test was considered

지표성분(2차 대사산물), 활성화 물질 1차 분석 데이터

The exotic grass-fire cycle is degrading semiarid rangelands, such as the vast areas of shrub-steppe in North America now invaded by fire-promoting cheatgrass. Chemical- or bio-herbicides are sprayed onto soils to inhibit the invaders, but information on chemical- or bio-herbicide effects on plant communities is limited. We asked how the plant community responded to the bioherbicide Pseudomonas fluorescens strain ACK55 (Battalion Pro®) in comparison to the separate and combined effects of the most conventional pre-emergent chemical herbicide, imazapic (Plateau®), in two cheatgrass-invaded sagebrush-steppe sites. Plant community responses are compared with soil microbial community responses in the Larger Work, and soil microbial data are available in GenBank. Plant community responses are compared with soil microbial community responses in the Larger Work, and soil microbial sequence data were deposited to the NCBI Short Read Archive (BioProject PRJNA1254875).

This dataset shows the measured response of the photosystems of seagrasses to herbicides in experiments conducted in 2012-2013. The data is provided as a multi-sheet spreadsheet. The aim of this study was to apply standard ecotoxicology protocols to quantify the concentrations of four priority PSII herbicides that inhibit photochemistry by 10, 20 and 50% (IC10, IC20 and IC50) over 72 hrs in two common seagrass species from the GBR lagoon. This data will enable improved assessment of the risks posed by PSII herbicides to tropical seagrass for both regulatory purposes and for comparison with other taxa. Methods: Four seagrass species (H. uninervis, C. rotundata, T. hemprichii and Z. muelleri) were used in preliminary studies to determine the time taken for PSII herbicides to affect photosynthesis, while more detailed ecotoxicology studies were undertaken with two of these species (H. uninervis and Z. muelleri). H. uninervis, C. rotundata and T. hemprichii were collected from intertidal seagrass meadows (<1 m) from Cockle Bay, Magnetic Island (19°10.88’ S, 146°50.63’ E) while Z. muelleri was collected from Pelican Banks, Gladstone, Australia (23°46.005’ S, 151°18.052’ E). Halodule uninervis, Cymodocea rotundata Ascherson (Cymodoceaceae) and Thalassia hemprichii Ascherson (Hydrocharitaceae) are tropical seagrass species widely distributed throughout the Indo-West Pacific while Zostera muelleri Irmisch ex Ascherson (Zosteraceae), (syn Zostera capricorni) is a tropical to temperate species found in Australia and New Zealand. Potted seagrasses were exposed to dissolved herbicides in static-replacement seawater (24 h water changes). All experiments were conducted under 273 ± 17 µmol photons m-2 s-1 (12h light:dark photoperiods, Aqua Illumination LED). This light intensity was chosen as the median daily irradiance at the Magnetic Island collection site. The glass aquaria were placed into water baths and maintained at 25.8 ± 0.3°C (range), equivalent to the annual average temperature in the GBR. Herbicide concentrations ranged from 0.1 to 300 µg herbicide l-1 depending on the potency of the herbicide. Duplicate tanks were used for each herbicide concentration and each tank contained individually potted seagrass plant of each species. Inhibition of photosynthesis was measured after 72 h exposure using pulse amplitude modulation (PAM) fluorometry. Two parameters were measured (effective quantum yield, deltaF/F’m and maximum quantum yield, Fv/Fm). The inhibition of photosynthetic yields relative to controls were plotted as dose-response curves by fitting inhibition data with measured concentrations using a 4 parameter logistic model (SigmaPlot 11). The herbicide inhibition concentrations (ICxx) that inhibited deltaF/F’m and Fv/Fm by 10, 20 and 50% (IC10, IC20 and IC50, respectively) were determined from each curve. Initially a series of pilot studies were performed to measure the time it takes for the four PSII herbicides to illicit 90% steady state (maximum) inhibition of effective quantum yield (deltaF/F’m) in Z. muelleri at single herbicide concentrations. These findings were used to ensure that the exposure duration of later dose-response curves was sufficient. The nominal herbicide concentrations used were 10 µg l-1 Diuron, 50 µg l-1 Atrazine, 10 µg l-1 Hexazinone and 400 µg l-1 Tebuthiuron. This data can be found in the “Kinetics” worksheet. We also exposed all four species of seagrass to 10 µg l-1 Diuron to examine the consistency of response times between species. Inhibition of deltaF/F’m by the herbicides compared with carrier controls were conducted at multiple times up to 24 h. This data can be found in the “4 seagrasses at Diuron 10ug_L” worksheet. Further information can be found in this publication: Flores F, Collier CJ, Mercurio P, Negri AP (2013) Phytotoxicity of Four Photosystem II Herbicides to Tropical Seagrasses. PLoS ONE 8(9): e75798. doi: 10.1371/journal.pone.0075798 Format:

Data, associated metadata, and calculation tools.. This dataset is not publicly accessible because: Data is controlled by Proctor and Gamble, and is available upon request. It can be accessed through the following means: Available from the upon request from Kristin Connors (connors.ka@pg.com). Format: Data, associated metadata, and calculation tools. This dataset is associated with the following publication: Connors, K., J. Brill, T. Norberg-King, M. Barron, G. Carr, and S. Belanger. Daphnia magna and Ceriodaphnia dubia Have Similar Sensitivity in Standard Acute and Chronic Toxicity Tests. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 41(1): 134-147, (2022).