Transgenerational Effect of Drought Stress and Sub-Lethal Doses of Quizalofop-p-ethyl: Decreasing Sensitivity to Herbicide and Biochemical Adjustment in Eragrostis plana

Abstract

(1) Background: Eragrostis plana Ness is a invasive C4 perennial grass in South America and very adaptable to environmental stresses. Our hypothesis is that there is a transgenerational cross-talk between environmental stresses and weed response to herbicides. This study’s objectives were to: (1) evaluate if E. plana primed by drought stress (DRY), a sub-lethal dose of quizalofop-p-ethyl (QPE), or a combination of both drought and herbicide stresses (DRY × QPE), produce a progeny with decreased sensitivity to quizalofop and (2) investigate the potential mechanisms involved in this adaptation; (2) Methods: A population of E. plana was isolatedly submitted to treatments for drought, quizalofop or drought plus quizalofop for two generations. The progenies were analyzed for sensitivity to the herbicide quizalofop and performed biochemical, chromatographic and molecular analyses.; (3) Results: In the G2 generation, the quizalofop-treated CHK population had reduced stomatal conductance and increased hydrogen peroxide and lipid peroxidation. On the other hand, there was no change in stomatal conductance, hydrogen peroxide level, and lipid peroxidation in the quizalofop-treated DRY population. In addition, this population had increased antioxidant enzyme activity and upregulated CYP72A31 and CYP81A12 expression, which was accompanied by reduced quizalofop-p-ethyl concentrations; (4) Conclusions: E. plana demonstrated a capacity for transgenerational adaptation to abiotic stresses, with the population exposed to drought stress (DRY) becoming less sensitive to quizalofop-p-ethyl treatment.

Environmental conditions affect herbicide selectivity on paddy rice in Southern Brazil

“…In addition to that, even being selective to the crops, herbicides promote biochemical and physiological alterations as a secondary effect, causing metabolism disorders in plants (DAYAN et al, 2019), increasing their toxicity and decreasing their selectivity (XIMENEZ et al, 2019). According to previous studies, reactive oxygen species (ROS) generation comprises one of the most common secondary effects promoted by herbicides (FIPKE et al, 2022;LUO et al, 2017). These molecules are generated during the peroxisome metabolism and are induced by environmental stimuli to which the plants are exposed (GUO et al, 2006).…”

Transgenerational memory of drought stress and low rates of glyphosate reduce the sensitivity of Eragrostis plana to the herbicide

“…H 2 O 2 content and lipid peroxidation measurement were performed using leaf tissues (0.250 g) to determine H 2 O 2 content according to Fipke et al (2022); and malondialdehyde (MDA) determination was performed according to (Fipke et al, 2022;Velikova et al, 2000).…”

“…Antioxidant enzymes: were performed with leaf tissues (0.250 g) to extract and determine SOD (EC 1.15.1.1), CAT (EC 1.11.1.6), APX (EC 1.11.1.11) activity adapted by Fipke et al (2022).…”

“…The amplification efficiency and specificity of each oligonucleotide were determined in validation experiments using four dilutions of cDNA. The reactions were performed following the protocol described by Fipke et al (2022). Gene expression was calculated following the 2^(-delta-delta CT) method (Livak, Schmittgen, 2001), using CHK population without glyphosate (0 g a.e.…”

“…The conjunction of factors, including the upregulation of EPSPS and the ABC MRP10 transporter, antioxidant enzymes seem to decrease the sensitivity of the DRYxGLY population to glyphosate. that plants adapted to abiotic stresses may have greater tolerance to herbicide stresses and vice-versa (Burns et al, 2018;Fipke et al, 2022). An increase in ROS-detoxifying enzymes promotes acclimation to drought and heat stress in Conyza bonariensis and Abutilon theophrasti, increasing the tolerance to paraquat and glyphosate (Dyer, 2018;Zhou et al, 2007).…”