Rapid Reduction of Herbicide Susceptibility in Junglerice by Recurrent Selection with Sublethal Dose of Herbicides and Heat Stress

Abstract

Global climate change, specifically rising temperature, can alter the molecular physiology of weedy plants. These changes affect herbicide efficacy and weed management. This research aimed to investigate the combined effect of heat stress (HS) and sublethal doses of herbicides (four active ingredients) on adaptive gene expression and efficacy of herbicide on Echinochloa colona (L.) Link (junglerice). Three factors were evaluated; factor A was E. colona generation (G0-original population from susceptible standard; G1 and G2 were progenies of recurrent selection), factor B was herbicide treatment (florpyrauxifen-benzyl, glufosinate-ammonium, imazethapyr, quinclorac and nontreated check) and factor C was HS (30 and 45 °C). The herbicides were applied at 0.125× the recommended dose. Recurrent exposure to HS, combined with sublethal doses of herbicides, favors the selection of plants less susceptible to the herbicide. Upregulation of defense (antioxidant) genes (APX: Ascorbate peroxidase), herbicide detoxification genes (CYP450 family: Cytochrome P450), stress acclimation genes (HSP: Heat shock protein, TPP: Trehalose phosphate phosphatase and TPS: Trehalose phosphate synthase) and genes related to herbicide conjugation (UGT: UDP Glucosyltransferase) was significant. The positive regulation of these genes may promote increased tolerance of E. colona to these herbicides.

Rapid photosynthetic and physiological response of 2,4-D–resistant Sumatran fleabane (Conyza sumatrensis) to 2,4-D as a survival strategy

“…The exposure of plants to herbicides may cause oxidative stress, leading to the generation of ROS, such as superoxide radicals (O 2 .− ), hydrogen peroxide (H 2 O 2 ), and hydroxyl radicals (•OH) (Caverzan et al 2019). In response to the damage caused by ROS, the antioxidative enzyme system (including superoxide dismutase [SOD], catalase [CAT], peroxidases, ascorbate peroxidase [APX], and glutathione reductase) (Gill and Tuteja 2010) may be differentially expressed/activated in resistant and susceptible biotypes (Benedetti et al 2020). The herbicide can also differentially modulate the induction of enzymatic antioxidant systems in resistant and susceptible biotypes (Caverzan et al 2019).…”

Florpyrauxifen-Benzyl Selectivity to Rice

“…Our results demonstrated no upregulation of this gene in rice after FPB application; however, other genes from this family may be affected by FPB application and different environmental factors. For example, CYP72A1 increases expression in E. colona treated with FPB (4.2-fold) compared with the untreated which was down-regulated (−0.3-fold), and this expression was greater induced when plants grow at optimal conditions (30 • C: 4.2-fold) and drought stress (4.2-fold) than at heat stress (45 • C: 3.2-fold) and well-watering (1.7-fold) [53,54]. Correspondingly, CYP72A15 was greater induced at 45 • C rather than at 30 • C (4.5-fold and 0.1-fold, respectively).…”

Recurrent Selection with Low Herbicide Rates and Salt Stress Decrease Sensitivity of Echinochloa colona to Imidazolinone

“…Markus et al [36] and Rouse [37] proposed epigenetic regulation models that may be involved in herbicide resistance and adaptation to abiotic stresses. Additionally, Benedetti et al [15,21] reported a reduction in sensitivity to certain herbicides in E. colona submitted to the recurrent selection of sublethal doses of herbicides and abiotic stresses, as drought and heat.…”

“…Weed control has been almost exclusively done with herbicides and when used at the conditions recommended and at the registered label rate, they cause very high mortality [12,13]. However, 'low-dose selection' of weed populations occurs in the field all the time, for example, in crop production fields arises from insufficient coverage of some individuals partially covered by other plants; variations in per-plant dose due to differences in weed size, weed density, field topography, or soil type; drift rates to populations on field edges; and other biological, physical, or environmental factors [14][15][16]. The recurrent selection at sublethal doses and the dynamics of resistance evolution are being investigated by some research groups, as previously reported in Amaranthus palmeri with dicamba, Avena fatua with diclofop-methyl, Lolium rigidum with glyphosate, Raphanus raphanistrum with 2,4-D, among others [14,[17][18][19][20].…”

“…We hypothesize that non-target site weed resistance evolution may be driven by sublethal rates of herbicides and by environmental stresses such as heat stress, drought stress, and salt stress [15,21]. Climate change impacts on the ecosystem need attention, such as soil and saline water management and the dynamics of interactions [22].…”