Phenols, Ozone, and Their Involvement in Pigmentation and Physiology of Plant Injury

Abstract Field trials were conducted to determine the effects of glyphosate and/or dicamba simulated drift rates on chipping potatoes ‘Atlantic’ and ‘Dakota Pearl’. Sublethal herbicide rates were applied at the tuber initiation stage and consisted of dicamba at 99 g ae ha−1 or glyphosate at 197 g ae ha−1 applied alone or the combinations of dicamba at 20 or 99 g ae ha−1 and glyphosate at 40 or 197 g ae ha−1, respectively. At 7 days after treatment (DAT), the high spray combination of glyphosate plus dicamba resulted in the greatest plant damage (28%). Plant injury from plants treated with the low combination of glyphosate plus dicamba did not differ from the nontreated control. At 21 DAT, visible injury increased to 40% for plants treated with the high combination of glyphosate plus dicamba treatment. Total yield suggested that dicamba and glyphosate caused similar yield reductions as plants that received glyphosate at 197 g ha−1 or dicamba at 99 g ha−1 had lower total yields compared to the nontreated and plants that received the combination of glyphosate (197 g ha−1) and dicamba (99 g ha−1) had lower total yields compared to plants that received either herbicide alone. However, ‘Dakota Pearl’ plants were more sensitive to glyphosate at 197 g ha−1 than ‘Atlantic’ causing the interaction for most tuber grades. Tuber specific gravity was lower for plants that received glyphosate at 197 g ha−1, dicamba at 99 g ha−1, or this combination, but this reduction would not prevent chip processing. Results reinforce the need for diligence when applying these herbicides in proximity to a susceptible crop such as chipping potatoes and the need to thoroughly clean sprayers before applications to a sensitive crop.

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Flux-Based Ozone Risk Assessment for a Plant Injury Index (PII) in Three European Cool-Temperate Deciduous Tree Species

Forests ◽

10.3390/f11010082 ◽

2020 ◽

Vol 11 (1) ◽

pp. 82 ◽

Cited By ~ 2

Author(s):

Yasutomo Hoshika ◽

Elisa Carrari ◽

Barbara Mariotti ◽

Sofia Martini ◽

Alessandra De Marco ◽

...

Keyword(s):

Risk Assessment ◽

Tree Species ◽

Growth Patterns ◽

Deciduous Tree ◽

Visible Injury ◽

Injury Index ◽

Leaf Formation ◽

Plant Level ◽

Plant Injury ◽

Species Specific

This study investigated visible foliar ozone (O3) injury in three deciduous tree species with different growth patterns (indeterminate, Alnus glutinosa (L.) Gaertn.; intermediate, Sorbus aucuparia L.; and determinate, Vaccinium myrtillus L.) from May to August 2018. Ozone effects on the timing of injury onset and a plant injury index (PII) were investigated using two O3 indices, i.e., AOT40 (accumulative O3 exposure over 40 ppb during daylight hours) and PODY (phytotoxic O3 dose above a flux threshold of Y nmol m−2 s−1). A new parameterization for PODY estimation was developed for each species. Measurements were carried out in an O3 free-air controlled exposure (FACE) experiment with three levels of O3 treatment (ambient, AA; 1.5 × AA; and 2.0 × AA). Injury onset was found in May at 2.0 × AA in all three species and the timing of the onset was determined by the amount of stomatal O3 uptake. It required 4.0 mmol m−2 POD0 and 5.5 to 9.0 ppm·h AOT40. As a result, A. glutinosa with high stomatal conductance (gs) showed the earliest emergence of O3 visible injury among the three species. After the onset, O3 visible injury expanded to the plant level as confirmed by increased PII values. In A. glutinosa with indeterminate growth pattern, a new leaf formation alleviated the expansion of O3 visible injury at the plant level. V. myrtillus showed a dramatic increase of PII from June to July due to higher sensitivity to O3 in its flowering and fruiting stage. Ozone impacts on PII were better explained by the flux-based index, PODY, as compared with the exposure-based index, AOT40. The critical levels (CLs) corresponding to PII = 5 were 8.1 mmol m−2 POD7 in A. glutinosa, 22 mmol m−2 POD0 in S. aucuparia, and 5.8 mmol m−2 POD1 in V. myrtillus. The results highlight that the CLs for PII are species-specific. Establishing species-specific O3 flux-effect relationships should be key for a quantitative O3 risk assessment.

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Direct Release of Ethylene from Methionine and Methionine Containing Peptides by Action of 13-Hydroperoxy-(9cis, 11trans)-octadecadienoic Acid

Zeitschrift für Naturforschung C ◽

10.1515/znc-1996-7-809 ◽

1996 ◽

Vol 51 (7-8) ◽

pp. 513-517 ◽

Cited By ~ 1

Author(s):

C. Scheick ◽

G. Spiteller

Keyword(s):

Mass Spectrometry ◽

Slow Release ◽

Octadecadienoic Acid ◽

Lipid Peroxides ◽

Time Interval ◽

Terminal Position ◽

Noic Acid ◽

Methionine Residue ◽

N Terminus ◽

Plant Injury

Abstract 13-Hydroperoxy-9cis,12trans-octadecadienoic acid (13-LOOH) reacts with methionine and methionine-containing peptides in absence of any other reagent by slow release of ethylene. Ethylene was identified by mass spectrometry and quantified by gas chromatography. The amount of ethylene released in a certain time interval depends on the position of the methionine residue in the peptide chain. Highest rates of ethylene release were measured with peptides carrying methionine at the N-terminus. 13-Hydroperoxy-9cis,12trans-octadecadie-noic acid can be substituted by linoleic acid, lipoxigenase and oxygen. We assume that the instant formation of lipid peroxides after plant injury and the instant release of ′wound ethylene′ are related. Since the initiator tRNA in eucaryontic cells always carries a methionine, all newly produced proteins contain methionine at the N-terminal position and are therefore sensitive to oxidative damage by hydroperoxides of fatty acids.

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Flue-cured tobacco tolerance to S-metolachlor

Weed Technology ◽

10.1017/wet.2020.71 ◽

2020 ◽

Vol 34 (6) ◽

pp. 843-848

Author(s):

Andrew M. Clapp ◽

Matthew C. Vann ◽

Charles W. Cahoon ◽

David L. Jordan ◽

Loren R. Fisher ◽

...

Keyword(s):

Field Experiments ◽

Leaf Quality ◽

Growing Seasons ◽

Application Rates ◽

Tobacco Production ◽

Leaf Yield ◽

Yield Quality ◽

Negative Impacts ◽

Plant Injury ◽

Injury Potential

AbstractCurrently, there are seven herbicides labeled for U.S. tobacco production; however, additional modes of action are greatly needed in order to reduce the risk of herbicide resistance. Field experiments were conducted at five locations during the 2017 and 2018 growing seasons to evaluate flue-cured tobacco tolerance to S-metolachlor applied pretransplanting incorporated (PTI) and pretransplanting (PRETR) at 1.07 (1×) and 2.14 (2×) kg ai ha−1. Severe injury was observed 6 wk after transplanting at the Whiteville environment in 2017 when S-metolachlor was applied PTI. End-of-season plant heights from PTI treatments at Whiteville were likewise reduced by 9% to 29% compared with nontreated controls, although cured leaf yield and value were reduced only when S-metolachlor was applied PTI at the 2× rate. Severe growth reduction was also observed at the Kinston location in 2018 where S-metolachlor was applied at the 2× rate. End-of-season plant heights were reduced 11% (PTI, 2×) and 20% (PRETR, 2×) compared with nontreated control plants. Cured leaf yield was reduced in Kinston when S-metolachlor was applied PRETR at the 2× rate; however, treatments did not impact cured leaf quality or value. Visual injury and reductions in stalk height, yield, quality, and value were not observed at the other three locations. Ultimately, it appears that injury potential from S-metolachlor is promoted by coarse soil texture and high early-season precipitation close to transplanting, both of which were documented at the Whiteville and Kinston locations. To reduce plant injury and the negative impacts to leaf yield and value, application rates lower than 1.07 kg ha−1 may be required in these scenarios.

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Methods To Measure Herbicide Volatility

Weed Science ◽

10.1614/ws-d-13-00127.1 ◽

2015 ◽

Vol 63 (SP1) ◽

pp. 116-120 ◽

Cited By ~ 6

Author(s):

Thomas C. Mueller

Keyword(s):

Environmental Protection Agency ◽

Target Area ◽

Negative Effects ◽

Agronomic Crops ◽

Chemical Agents ◽

Nontarget Species ◽

Time Of Year ◽

Plant Injury ◽

Herbicide Drift ◽

Herbicide Use

Herbicides are powerful chemical agents that exert strong biological activity on plants. The release of new formulations of dicamba and 2,4-D and their use in transgenic agronomic crops will probably result in many more applications during the time of year when sensitive nontarget vegetation will be present. The use of herbicides is regulated by the U.S. Environmental Protection Agency, and there are usually no negative effects on nontarget species. One negative aspect of herbicide use occurs when the application moves away from the target area and causes unwanted plant injury on susceptible species. Interest in herbicide drift is increasing, as evidenced by the number of refereed articles that investigate the mitigation or potential for herbicide drift (Figure 1). Although the topic of herbicide drift is broad, in this manuscript I will focus on an overview of off-site movement from a historical perspective and then discuss specific research protocols to examine vapor drift.

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Dry Pea (Pisum sativumL.) Response to Low Rates of Selected Foliar- and Soil-Applied Sulfonylurea and Growth Regulator Herbicides

Weed Technology ◽

10.1017/s0890037x00042184 ◽

1999 ◽

Vol 13 (4) ◽

pp. 753-758 ◽

Cited By ~ 15

Author(s):

Kassim Al-Khatib ◽

Ajit Tamhane

Keyword(s):

United States ◽

Pisum Sativum ◽

Growth Regulator ◽

Field Experiments ◽

The United States ◽

Large Reduction ◽

Soil Application ◽

Effect On Yield ◽

Plant Injury ◽

Significant Injury

Field experiments on dry pea (Pisum sativum) were conducted at five locations across the United States in 1995 and 1996 to investigate the effects of low rates of chlorsulfuron, thifensulfuron, and dicamba applied postemergence and of chlorsulfuron, metsulfuron, and clopyralid applied preplant incorporated in the soil on pea plants. Although chlorsulfuron, thifensulfuron, and dicamba caused significant injury symptoms on pea plants, they had little effect on yield. The lowest rates of foliar applications that caused observable symptoms were 0.035, 0.086, and 1.56 g ai/ha for chlorsulfuron, thifensulfuron, and dicamba, respectively, whereas chlorsulfuron, thifensulfuron, and dicamba rates that reduced pea yield by 25% were 0.18, 1.36, and 25 g/ha, respectively. Clopyralid caused more injury symptoms than metsulfuron or chlorsulfuron with soil application. However, the lowest rates of chlorsulfuron, metsulfuron, and clopyralid that caused observable symptoms were lower than the rates that reduced yield. This study showed that pea plants can sustain some level of plant injury without a large reduction in yield.

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Sensitivity of sunflower cultivar PR63E82 to tribenuron and propaquizafop in different weather conditions

Plant Soil and Environment ◽

10.17221/343/2018-pse ◽

2018 ◽

Vol 64 (No. 10) ◽

pp. 479-483

Author(s):

Tichý Lukáš ◽

Jursík Miroslav ◽

Kolářová Michaela ◽

Hejnák Václav ◽

Andr Jiří ◽

...

Keyword(s):

Czech Republic ◽

Growth Retardation ◽

Weather Conditions ◽

Field Trials ◽

Ionic Surfactant ◽

Leaf Chlorosis ◽

Herbicide Treatments ◽

Small Plot ◽

Plant Injury

The aim of this work was to verify and assess the tolerance of the PR63E82 (ExpressSun) sunflower cultivar to tribenuron, propaquizafop and their tank-mix combination in two rates under various weather conditions. Three small-plot field trials were carried out on sunflower in Prague, Czech Republic, from 2015 to 2017. High phytotoxicity (25–56%) of tribenuron (TBM) + non-ionic surfactant was observed in 2015 and 2016 when the sunflower was sown in mid-April. In 2017, phytotoxicity was significantly lower (4–6%), probably due to a later sowing of sunflower (May), and hence higher temperatures. The main symptoms of TBM phytotoxicity were leaf chlorosis, necrosis and growth retardation. Propaquizafop (PQF) injury was minimal in 2015 and 2017. A higher phytotoxicity (10–13%) was recorded in 2016, probably due to a hail which occurred 2 days after T2 (second application term (sunflower BBCH 14)) application. Plant injury had puckered leaves and also made more side branches. TBM + PQF damaged sunflower plants most of the tested herbicide treatments (phytotoxicity 3–62%). High phytotoxicity caused stem branching, increased number of sunflower heads and decreased yield.

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