Abstract
In the last 60 years, auxinic herbicides like 2,4-dichlorophenoxyacetic acid (2,4-D) have been among the widest and successful herbicides used in agriculture because it is a selective herbicide that kills dicots and mimics the natural plant phytohormone indol-3-acetic acid (IAA) at the molecular level. In spite of industry attempts to reformulate 2,4-D-based herbicides and reduce their off-target movement, damage has been reported on sensitive plants, like tomato, at low ratesdi. Therefore, it is important to study the responses of such species to such conditions so that yield losses can be avoided or, at least, reduced. It is known that ethylene, abscisic acid (ABA) and reactive oxygen species (ROS) play a central role in 2,4-D toxicity, leading to numerous unbeneficial changes in plant tissues. Yet, how glutathione-related defense- and/or stress-related genes’ expressions are affected needs to be more studied. In this study, tomato plants (Solanum lycopersicum L.) were used to determine the expression and participation of the different GST phi class gene family members, plus the plans’ antioxidant system, in response to 2,4-D. When tomato plants were root-treated with 2.26 mM 2,4-D for 48 h, H2O2 and O2•− levels increased in shoots. Contrarily, in roots, 2,4-D did not provoke clear symptoms of oxidative stress, as lipid peroxidation, H2O2 and O2•− levels decreased. Despite the difference in ROS levels observed in both organs, the exposure of tomato plants to 2,4-D lead to the activation of key antioxidant enzymes in both organs, apart from superoxide dismutase (SOD), whose activity increased only in roots, while ascorbate peroxidase (APX) and catalase (CAT) activities increased in both. Also, tomato plants responded to 2.26 mM 2,4-D by increasing Ascorbate (AsA) levels in both organs while an increase in Glutathione (GSH) was only observed in shoots. The herbicide increased both the synthesis and the regeneration of GSH, as well as its usage to conjugate 2,4-D, as shoot γ-glutamyl-cysteinyl synthetase (γ-ECS), glutathione reductase (GR) and glutathione S-transferase (GST) activities increased. Shoot GST increased activity was due to an increased expression of SlGSTF4 and SlGSTF5, while no SlGSTFs increased their expression in roots. Shoots and roots of tomato plants were differentially affected by 2.26 mM 2,4-D, with 2,4-D detoxification occurring predominantly in leaves, with the specific participation of the GST phi class members SlGSTF4 and SlGSTF5. Also, this study reinforces the notion that the cultivation of tomato in 2,4-D-contaminated soils may result in yield reduction.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 12
Claim · model-written summary
Root-treated 2.26 mM 2,4-D for 48 h increased H2O2 and O2•− levels in tomato shoots.
- Taxon
- tomato
Solanum lycopersicumt0 - Organ / stage
- shootse1
- Treatment
- root-treated with 2.26 mM 2,4-D for 48 he1
- Outcome
- H2O2 and O2•− levelse1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“When tomato plants were root-treated with 2.26 mM 2,4-D for 48 h, H2O2 and O2•− levels increased in shoots”
Claim · model-written summary
2,4-D decreased lipid peroxidation, H2O2 and O2•− levels in tomato roots.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- rootse1
- Treatment
- 2,4-De1
- Outcome
- lipid peroxidation, H2O2 and O2•− levelse1
- Direction
- decreasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“in roots, 2,4-D did not provoke clear symptoms of oxidative stress, as lipid peroxidation, H2O2 and O2•− levels decreased”
Claim · model-written summary
2,4-D increased superoxide dismutase (SOD) activity only in tomato roots.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- rootse1
- Treatment
- 2,4-De1
- Gene
- superoxide dismutase (SOD)e1
- Outcome
- activitye1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“the exposure of tomato plants to 2,4-D lead to the activation of key antioxidant enzymes in both organs, apart from superoxide dismutase (SOD), whose activity increased only in roots, while ascorbate peroxidase (APX) and catalase (CAT) activities increased in both”
Claim · model-written summary
2,4-D increased ascorbate peroxidase (APX) and catalase (CAT) activities in both organs of tomato.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- both organse1
- Treatment
- 2,4-De1
- Gene
- ascorbate peroxidase (APX) and catalase (CAT)e1
- Outcome
- activitiese1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“the exposure of tomato plants to 2,4-D lead to the activation of key antioxidant enzymes in both organs, apart from superoxide dismutase (SOD), whose activity increased only in roots, while ascorbate peroxidase (APX) and catalase (CAT) activities increased in both”
Claim · model-written summary
2,4-D increased ascorbate (AsA) levels in both organs of tomato.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- both organse1
- Treatment
- 2.26 mM 2,4-De1
- Outcome
- Ascorbate (AsA) levelse1
- Direction
- increasinge1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“tomato plants responded to 2.26 mM 2,4-D by increasing Ascorbate (AsA) levels in both organs while an increase in Glutathione (GSH) was only observed in shoots”
Claim · model-written summary
2,4-D increased glutathione (GSH) only in tomato shoots.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- shootse1
- Treatment
- 2.26 mM 2,4-De1
- Outcome
- Glutathione (GSH)e1
- Direction
- increasee1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“tomato plants responded to 2.26 mM 2,4-D by increasing Ascorbate (AsA) levels in both organs while an increase in Glutathione (GSH) was only observed in shoots”
Claim · model-written summary
The herbicide increased GSH synthesis and regeneration in tomato.
- Taxon
- tomatoSolanum lycopersicumt0
- Treatment
- The herbicidee1
- Outcome
- synthesis and the regeneration of GSHe1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“The herbicide increased both the synthesis and the regeneration of GSH, as well as its usage to conjugate 2,4-D, as shoot γ-glutamyl-cysteinyl synthetase (γ-ECS), glutathione reductase (GR) and glutathione S-transferase (GST) activities increased”
Claim · model-written summary
The herbicide increased GSH use for conjugating 2,4-D in tomato.
- Taxon
- tomatoSolanum lycopersicumt0
- Treatment
- The herbicidee1
- Outcome
- its usage to conjugate 2,4-De1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“The herbicide increased both the synthesis and the regeneration of GSH, as well as its usage to conjugate 2,4-D, as shoot γ-glutamyl-cysteinyl synthetase (γ-ECS), glutathione reductase (GR) and glutathione S-transferase (GST) activities increased”
Claim · model-written summary
The herbicide increased activities of gamma-ECS, glutathione reductase and GST in tomato shoots.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- shoote1
- Treatment
- The herbicidee1
- Gene
- γ-glutamyl-cysteinyl synthetase (γ-ECS), glutathione reductase (GR) and glutathione S-transferase (GST)e1
- Outcome
- activitiese1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“The herbicide increased both the synthesis and the regeneration of GSH, as well as its usage to conjugate 2,4-D, as shoot γ-glutamyl-cysteinyl synthetase (γ-ECS), glutathione reductase (GR) and glutathione S-transferase (GST) activities increased”
Claim · model-written summary
Increased shoot GST activity was due to increased expression of SlGSTF4 and SlGSTF5 in tomato.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- Shoote1
- Gene
- SlGSTF4 and SlGSTF5e1
- Outcome
- Shoot GST increased activitye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“Shoot GST increased activity was due to an increased expression of SlGSTF4 and SlGSTF5, while no SlGSTFs increased their expression in roots”
Claim · model-written summary
No SlGSTF gene increased its expression in tomato roots after 2,4-D.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- rootse1
- Treatment
- 2.26 mM 2,4-De2
- Gene
- SlGSTFse1
- Outcome
- expressione1
- Direction
- no_changeinferrede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“Shoot GST increased activity was due to an increased expression of SlGSTF4 and SlGSTF5, while no SlGSTFs increased their expression in roots”
e2“Shoots and roots of tomato plants were differentially affected by 2.26 mM 2,4-D”
Claim · model-written summary
2,4-D detoxification in tomato occurs predominantly in leaves, with SlGSTF4 and SlGSTF5 participating.
- Taxon
- tomatoSolanum lycopersicumt0
- Organ / stage
- leavese1
- Gene
- SlGSTF4 and SlGSTF5e1
- Outcome
- 2,4-D detoxificatione1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaves”
e1“with 2,4-D detoxification occurring predominantly in leaves, with the specific participation of the GST phi class members SlGSTF4 and SlGSTF5”
The same questions in other papers
2,4-D · physiology: oxidative · Solanum lycopersicum (tomato)Positive and negative results
1 in the opposite direction
- negative
2,4-D · molecular: expression · Solanum lycopersicum (tomato)Positive and negative results
2 in the opposite direction
- positive
- positive
2,4-D · molecular: metabolites · Solanum lycopersicum (tomato)Results agree
1 paper in the same direction as this paper
- positive
herbicide · growth · Solanum lycopersicum (tomato)Positive and negative results
11 papers in the same direction as this paper · 8 in the opposite direction
- negative
- no effect
- negative
16 papers more in this group
See all 20 papers →herbicide · molecular: metabolites · Solanum lycopersicum (tomato)Results agree
1 paper in the same direction as this paper
- positive
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.