Interaction of pretilachlor with PS‐II activity of the cyanobacterium Desmonostoc muscorum PUPCCC 405.10

Abstract

Interaction of pretilachlor with photosystem (PS)‐II of the cyanobacterium Desmonostoc muscorum PUPCCC 405.10 has been studied in this paper. Pretilachlor negatively affected growth, chlorophyll a (Chl a), photosynthesis, and carbon dissimilation in a dose‐dependent manner. Effects were also observed in PSs, especially PS‐II (an 11–35% decrease), as well as the whole photosynthetic electron transport activity. The fluorescence emission spectrum of Chl a revealed a dose‐dependent effect of pretilachlor on both the antenna and the core complex of PSs, with more severe effect on the former. Data of O‐J‐I‐P fluorescence transient of Chl a revealed that pretilachlor interfered with electron flow between QA and QB sites of PS‐II. It was further observed that pretilachlor decreased maximum fluorescence, variable and relative variable fluorescence, maximum quantum yield, quantum yield of electron transport, the rate of trapped exciton movement, quantum yield of electron transfer, and performance index of primary photochemistry; however, there was a progressive increase in the net rate of PS‐II closure, quantum yield of energy dissipation, and effective antenna size per active reaction center. A decrease in photosynthetic activity leads to a decrease in carbon dissimilation, as evidenced by low activity of glucose‐6‐phosphate dehydrogenase and pyruvate kinase. Thus, pretilachlor, which is otherwise known to kill weeds by interfering with cell division, affected the growth of the cyanobacteria by interacting with PS‐II.

Ultimate fate, transformation, and toxicological consequences of herbicide pretilachlor to biotic components and associated environment: An overview

“…was found to be maximum in untreated supra‐optimum and suboptimum light acclimatized cells, respectively. In another study, similar toxicological results were obtained in a test over Desmonostoc muscorum using different concentrations (2.5–15 mg/L) of pretilachlor, which revealed a dose‐dependent growth inhibition of cultures (Swatch et al, 2020). At higher concentration of pretilachlor (15 mg/L), the species did not survive, and cells were ruptured with release of pigments in medium.…”

“…pretilachlor, which revealed a dose-dependent growth inhibition of cultures (Swatch et al, 2020). At higher concentration of pretilachlor (15 mg/L), the species did not survive, and cells were ruptured with release of pigments in medium.…”

Long-Chain Molecules with Agro-Bioactivities and Their Applications

“…Pretilachlor ( 48) is a selective pre-or post-emergence herbicide that belongs to the chloroacetanilide class (Figure 24). It is widely used to control broadleaved weeds, various grasses, and sedges in transplanted and directly seeded paddy fields [139][140][141][142][143][144][145][146][147][148]. Pretilachlor works by inhibiting the synthesis of very-long-chain fatty acids (VLCFAs) and cell division.…”

A Sensitive and Specific Monoclonal Antibody Based Enzyme-Linked Immunosorbent Assay for the Rapid Detection of Pretilachlor in Grains and the Environment

“…Consequently, it has gained widespread application in rice transplanting and weed management practices [ 3 ]. But its overuse has potential problems, such as increased weed resistance and contamination of the surrounding environment; PR has also shown toxic effects on fish [ 2 , 4 , 5 , 6 , 7 ], and algae [ 8 , 9 ]. It is important to note that the perceived low toxicity of PR is relative and prolonged ultra-limited exposure still carries risks.…”