1
|
Adu-Yeboah P, Lowor ST, Segbefia MA, Konlan S, Pobee P. Physiological and growth responses of cacao to glyphosate exposure. J Environ Sci Health B 2023; 58:91-99. [PMID: 36708092 DOI: 10.1080/03601234.2023.2169523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Herbicide drift phytotoxicity is a problem in plantation crops due to application failures and unfavorable spray conditions. With the increased use of glyphosate in cacao plantations in Ghana, there are concerns about the effect on cacao growth and productivity from doses that potentially could be expected from drift. The aim of this study was to evaluate the physiological and growth response of young cacao plants exposed to glyphosate. Two field experiments were conducted in randomized blocks, with four replications. Glyphosate was applied at rates 0 to 720 g a.e. ha-1. Crop injury, shikimate accumulation, chlorophyll content, quantum efficiency of PSІІ (Fv/Fm), height, and stem diameter were evaluated. Increased glyphosate rates increased crop injury and shikimate accumulation and decreased chlorophyll content, quantum efficiency of PSІІ (Fv/Fm), and plant growth. Glyphosate rates 360 g a.e. ha-1 or higher resulted in >60% foliar injury and more than 10-fold increase in shikimate accumulation. Glyphosate reduced chlorophyll content to <10 and Fv/Fm to <0.35 at the highest rates. Glyphosate rates ≥180 g a.e. ha-1 reduced height and stem diameter of plants and caused reductions in stand count. Thus, cacao showed sensitivity to glyphosate, and severe injury impaired plant growth.
Collapse
Affiliation(s)
| | | | | | | | - Prince Pobee
- Cocoa Research Institute of Ghana, New Tafo-Akim, Ghana
| |
Collapse
|
2
|
Borges MPDS, Silva DV, Souza MDF, Silva TS, Teófilo TMDS, da Silva CC, Pavão QS, Passos ABRDJ, Dos Santos JB. Glyphosate effects on tree species natives from Cerrado and Caatinga Brazilian biome: Assessing sensitivity to two ways of contamination. Sci Total Environ 2021; 769:144113. [PMID: 33486169 DOI: 10.1016/j.scitotenv.2020.144113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/18/2020] [Accepted: 11/21/2020] [Indexed: 06/12/2023]
Abstract
Glyphosate is applied for dissection in no-till and post-emergence management in transgenic crops in agricultural fields near the Cerrado and Caatinga biomes. These biomes together represent 33.8% of the Brazilian territory, contributing to the maintenance of great world diversity in flora and fauna. Despite actions to protect them, the proximity with agricultural areas and intense use of glyphosate puts at risk the preservation of native vegetation due to the contamination via herbicide transport processes. Our objectives were: i) to determine the sensitivity of native species from the Cerrado and Caatinga to glyphosate contamination via drift and groundwater; ii) evaluate the level of sensitivity to glyphosate among the different organs of plants. The highest intoxications (upper 80%) were observed for Bauhinia cheilantha, Mimosa caesalpiniaefolia, Mimosa tenuiflora and Amburana cearensis due to drift simullation. The species with 90% of total dry matter reduction were Bauhinia cheilantha, Enterolobium contortisiliquum, Mimosa caesalpiniaefolia, Mimosa tenuiflora, Tabebuia aurea. B. cheilantha and M. tenuiflora are most affected by exposure to glyphosate drift, with 50% of total dry matter reduction when exposed to doses below 444,0 g ha-1. Leaf growth is more sensitive to glyphosate for drift exposure for most species. Hymenaea courbaril is an exception, with greater sensitivity to root growth (50% dry matter reduction at doses below 666,0 g ha-1). B. cheilantha is the species most sensitive to drift exposure; however, it showed complete tolerance to contamination in subsurface waters. Other species such as Anadenanthera macrocarpa and M. caesalpiniifolia are also sensitive to drift, but without reach 90% of total dry matter reduction. A. macrocarpa, M. caesalpiniifolia and T. aurea were tolerant to contamination by subsurface water. The differential tolerance of trees confirms glyphosate's potential as a species selection agent in the Cerrado and Caatinga biomes.
Collapse
Affiliation(s)
- Maiara Pinheiro da Silva Borges
- Universidade Federal Rural do Semi-Árido, Agricultural Science Center, Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900 Mossoró, RN, Brazil.
| | - Daniel Valadão Silva
- Universidade Federal Rural do Semi-Árido, Agricultural Science Center, Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900 Mossoró, RN, Brazil
| | - Matheus de Freitas Souza
- Universidade Federal Rural do Semi-Árido, Agricultural Science Center, Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900 Mossoró, RN, Brazil
| | - Tatiane Severo Silva
- Universidade Federal Rural do Semi-Árido, Agricultural Science Center, Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900 Mossoró, RN, Brazil
| | - Taliane Maria da Silva Teófilo
- Universidade Federal Rural do Semi-Árido, Agricultural Science Center, Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900 Mossoró, RN, Brazil
| | - Cydianne Cavalcante da Silva
- Universidade Federal Rural do Semi-Árido, Agricultural Science Center, Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900 Mossoró, RN, Brazil
| | - Quésia Sá Pavão
- Universidade Federal Rural do Semi-Árido, Agricultural Science Center, Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900 Mossoró, RN, Brazil
| | - Ana Beatriz Rocha de Jesus Passos
- Universidade Federal Rural do Semi-Árido, Agricultural Science Center, Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900 Mossoró, RN, Brazil
| | - José Barbosa Dos Santos
- Universidade Federal dos Vales do Jequitinhonha e Mucuri - Campus JK, Agricultural Science Center, Rodovia MGT 367, Km 583, n° 5000, Alto da Jacuba, CEP: 39100-000 Diamantina, MG, Brazil
| |
Collapse
|
3
|
Carpenter DJ, Mathiassen SK, Boutin C, Strandberg B, Casey CS, Damgaard C. Effects of Herbicides on Flowering. Environ Toxicol Chem 2020; 39:1244-1256. [PMID: 32170767 DOI: 10.1002/etc.4712] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 12/10/2019] [Accepted: 03/06/2020] [Indexed: 06/10/2023]
Abstract
Herbicides have been shown to reduce flower production and to delay flowering, with results varying among herbicides and tested plant species. We investigated the effects of herbicides on flowering in an extensive greenhouse study conducted in Canada and Denmark. The effects of low doses of 5 different herbicides (bromoxynil, ioxynil + bromoxynil, metsulfuron-methyl, clopyralid, and glyphosate), simulating realistic drift scenarios (1 and 5% recommended field rates), on plant flowering were examined using 9 wild plant species exposed at either the seedling (6- to 8-leaf) or flower bud stage. Following herbicide exposure, initial flowering date as well as flower production over time were recorded over the growing period. The effect of herbicides on cumulative flower numbers and flowering time were modeled using Gompertz growth models. Significant delays to peak flowering and/or reductions in flower production were observed in at least one plant species for all tested herbicides, with glyphosate often exhibiting the greatest negative effects, that is, plant death. Except for ioxynil + bromoxynil, there was no clear evidence of either the seedling or the flower bud stage being more sensitive. Overall, 58% of all species × life stage × herbicide treatments resulted in either a statistically significant or a strong decline in flower production with herbicide application rates up to 5% of recommended field rates, whereas significant or strong delays in peak flowering were also detected but were slightly less common. Effects at 1% label rates were minimal. Simultaneous delays to peak flowering and reductions in total flower production occurred in approximately 25% of all cases, indicating that herbicide application rates simulating realistic drift scenarios would likely have negative effects on wild floral communities. Environ Toxicol Chem 2020;39:1244-1256. © 2020 SETAC.
Collapse
Affiliation(s)
- David J Carpenter
- Environment and Climate Change Canada, Science and Technology Branch, Carleton University, Ottawa, Ontario, Canada
| | | | - Céline Boutin
- Environment and Climate Change Canada, Science and Technology Branch, Carleton University, Ottawa, Ontario, Canada
| | | | - Carlene S Casey
- Environment and Climate Change Canada, Science and Technology Branch, Carleton University, Ottawa, Ontario, Canada
| | | |
Collapse
|
4
|
Boutin C, Montroy K, Mathiassen SK, Carpenter DJ, Strandberg B, Damgaard C. Effects of Sublethal Doses of Herbicides on the Competitive Interactions Between 2 Nontarget Plants, Centaurea cyanus L. and Silene noctiflora L. Environ Toxicol Chem 2019; 38:2053-2064. [PMID: 31145498 DOI: 10.1002/etc.4506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 02/20/2019] [Accepted: 05/23/2019] [Indexed: 06/09/2023]
Abstract
Plant competitive interactions influence the effect of herbicides, and the effect of competitive interactions on plant responses may be important to include in the ecological risk assessment of herbicides. In the present study the effect of competitive interactions and sublethal doses of 2 herbicides on plant species was investigated in competition experiments and fitted to empirical competition models. Two nontarget species commonly found in agroecosystems (Centaurea cyanus L. and Silene noctiflora L.) and 2 herbicides (glyphosate and metsulfuron methyl) were used in separate experiments. Plants were sprayed at the 6- to 8-leaf stage. Effects of herbicide treatments and plant density were modeled by generalization of a discrete hyperbolic competition model. The 10% effective dose (ED10) was calculated for C. cyanus. All experiments showed that as density increased, plants were negatively affected. Furthermore, in all cases, C. cyanus remained a better competitor than S. noctiflora. Nevertheless, the density of S. noctiflora (competitor) was an influential element in determining the ED10 of C. cyanus measured at the mature stage. With herbicide exposure, the competitive interactions were further altered; C. cyanus was less affected by glyphosate when S. noctiflora increased to high density. In contrast, at the young stage, conspecific density was important in determining the sensitivity of C. cyanus to metsulfuron methyl, whereas the density of the competitor S. noctiflora had a limited influence. Overall, the results demonstrate the importance of integrating the effect of herbicide and species interactions measured at the reproductive stage into the ecological risk assessments of pesticides. Environ Toxicol Chem 2019;38:2053-2064. © 2019 SETAC.
Collapse
Affiliation(s)
- Céline Boutin
- Science and Technology Branch, Environment and Climate Change Canada, Carleton University, Ottawa, Ontario, Canada
| | - Kaitlyn Montroy
- Science and Technology Branch, Environment and Climate Change Canada, Carleton University, Ottawa, Ontario, Canada
| | | | - David J Carpenter
- Science and Technology Branch, Environment and Climate Change Canada, Carleton University, Ottawa, Ontario, Canada
| | | | | |
Collapse
|
5
|
Egan JF, Graham IM, Mortensen DA. A comparison of the herbicide tolerances of rare and common plants in an agricultural landscape. Environ Toxicol Chem 2014; 33:696-702. [PMID: 24488525 DOI: 10.1002/etc.2491] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/12/2013] [Accepted: 11/07/2013] [Indexed: 06/03/2023]
Abstract
Declining plant biodiversity in agroecosystems has often been attributed to escalating use of chemical herbicides, but other changes in farming systems, including the clearing of seminatural habitat fragments, confound the influence of herbicides. The present study introduces a new approach to evaluate the impacts of herbicide pollution on plant communities at landscape or regional scales. If herbicides are in fact a key factor shaping agricultural plant diversity, one would expect to see the signal of past herbicide impacts in the current plant community composition of an intensively farmed region, with common, successful species more tolerant to widely used herbicides than rare or declining species. Data from an extensive field survey of plant diversity in Lancaster County, Pennsylvania, USA, were compared with herbicide bioassay experiments in a greenhouse to test the hypothesis that common species possess higher herbicide tolerances than rare species. Five congeneric pairs of rare and common species were treated with 3 commonly used herbicide modes of action in bioassay experiments, and few significant differences were found in the tolerances of rare species relative to common species. These preliminary results suggest that other factors beyond herbicide exposure may be more important in shaping the distribution and abundance of plant species diversity across an agricultural landscape.
Collapse
Affiliation(s)
- J Franklin Egan
- Department of Plant Science, The Pennsylvania State University, University Park, Pennsylvania, USA
| | | | | |
Collapse
|
6
|
Olszyk D, Blakeley-Smith M, Pfleeger T, Lee EH, Plocher M. Effects of low levels of herbicides on prairie species of the Willamette Valley, Oregon. Environ Toxicol Chem 2013; 32:2542-51. [PMID: 23881750 DOI: 10.1002/etc.2331] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 04/26/2013] [Accepted: 07/17/2013] [Indexed: 06/02/2023]
Abstract
The relative sensitivity of 17 noncrop plant species from Oregon's Willamette Valley was determined in response to glyphosate, tribenuron methyl (tribenuron), and fluazifop-p-butyl (fluazifop) herbicides. For glyphosate, Elymus trachycaulus, Festuca arundinacea, Madia elegans, Potentilla gracilis, and Ranunculus occidentalis were the most sensitive species, based on a concentration calculated to reduce shoot dry weight by 25% (IC25 values) of 0.02 to 0.04 × a field application rate of 1112 g active ingredient (a.i.) per hectare. Clarkia amoena and Lupinus albicaulis were the most tolerant to glyphosate, with IC25 values near the field application rate. Clarkia amoena, Prunella vulgaris, and R. occidentalis were the most sensitive to tribenuron, with IC25 values of 0.001 to 0.004 × a field application rate of 8.7 g a.i. ha(-1) for shoot dry weight. Five grass species were tolerant to tribenuron with no significant IC25 values. For fluazifop, 2 native grasses, E. trachycaulus and Danthonia californica, were the most sensitive species, with IC25 values of 0.007 and 0.010 × a field application rate of 210 g a.i. ha(-1) , respectively, for shoot dry weight, while a native grass, Festuca roemeri, and nearly all forbs showed little or no response. These results also indicated that the 3 introduced species used in the present study may be controlled with 1 of the tested herbicides: glyphosate (F. arundinacea), tribenuron (Leucanthemum vulgare), and fluazifop (Cynosurus echinatus).
Collapse
Affiliation(s)
- David Olszyk
- US Environmental Protection Agency, National Health and Environmental Effects Research Laboratory, Western Ecology Division, Corvallis, Oregon
| | | | | | | | | |
Collapse
|