Clomazone exposure-driven photosynthetic responses plasticity of Pontederia crassipes.

Autor: Rodrigues BJS; Department of Botany, Federal University of Pelotas (UFPel), C.P. 354, Pelotas, RS, 96160-000, Brazil., de Moura Silva IA; Institute of Biological Sciences, Federal University of Rio Grande (FURG), C.P. 474, Rio Grande, RS, 96203-900, Brazil., Dos Santos Silva M; Department of Botany, Federal University of Pelotas (UFPel), C.P. 354, Pelotas, RS, 96160-000, Brazil., Posso DA; Department of Botany, Federal University of Pelotas (UFPel), C.P. 354, Pelotas, RS, 96160-000, Brazil., Hüther CM; Department of Agricultural and Environmental Engineering, Federal Fluminense University (UFF), C.P. 156, Niterói, RJ, 24210-240, Brazil., do Amarante L; Department of Botany, Federal University of Pelotas (UFPel), C.P. 354, Pelotas, RS, 96160-000, Brazil., Bacarin MA; Department of Botany, Federal University of Pelotas (UFPel), C.P. 354, Pelotas, RS, 96160-000, Brazil., Borella J; Department of Botany, Federal University of Pelotas (UFPel), C.P. 354, Pelotas, RS, 96160-000, Brazil. borellaj@gmail.com.; Institute of Biological Sciences, Federal University of Rio Grande (FURG), C.P. 474, Rio Grande, RS, 96203-900, Brazil. borellaj@gmail.com.
Jazyk: angličtina
Zdroj: Environmental science and pollution research international [Environ Sci Pollut Res Int] 2024 Nov; Vol. 31 (51), pp. 61220-61235. Date of Electronic Publication: 2024 Oct 16.
DOI: 10.1007/s11356-024-35319-x
Abstrakt: Clomazone is known to contaminate aquatic environments and have a negative impact on macrophytes. However, recent reports suggests that Pontederia crassipes Mart. can withstand clomazone exposure while maintaining growth rates. We hypothesized that this maintenance of growth is supported by photosynthetic plasticity of old leaves (developed before herbicide application), while new leaves (developed after application) exhibit phytotoxic symptoms. To investigate, two experiments were conducted with doses ranging from 0.1 mg L -1 to 0.5 mg L -1 plus untreated controls. Various parameters were measured in old and new leaves over 7, 12, and 15 d post-application, including visual symptoms, chlorophyll index, photosynthetic pigments, chlorophyll fluorescence, gas exchange, glycolate oxidase activity, carbohydrate content, leaf epidermis anatomy, and growth parameters. Clomazone exposure induced chlorosis, particularly in new leaves across all doses. These visual symptoms were accompanied by stomatal closure, restricting gas exchange and CO 2 fixation, leading to reduced photosynthetic rates and carbohydrate synthesis. However, clomazone did not affect old leaves, which maintained photosynthetic activity, sustaining essential metabolic processes of the plant, including reproductive functions. By ensuring high reproductive rates and metabolic continuity, old leaves supported the species' persistence despite clomazone presence.
(© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
Databáze: MEDLINE
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