Abstract
Abstract Amounts of extractable phenylalanine ammonia‐lyase (PAL; E.C. 4.3.1.5) activity increased in the axes of 3–day‐old, dark‐grown soybean seedlings [ Glycine max (L.) Merr.] shortly after the seedlings were transferred to glyphosate [ N ‐(phosphonomethyl)‐glycine] solutions. The stimulation of PAL activity in herbicide‐treated tissue (as compared to control tissue) was detectable as early as 12 h after treatment, whereas growth inhibition (length, fresh weight and dry weight) was not significantly affected until 24 h on a fresh‐weight basis and at 48 h on a dry‐weight basis. PAL activity increased with time (12–72 h) in herbicide‐treated axes when expressed as activity per gram fresh weight, specific activity, and on a per axis basis. PAL activity stimulation correlated positively with glyphosate concentration from 10 –4 to 10 –3 M . PAL activity in control tissues remained nearly constant over the sampling period (12–72 h). Total alcohol‐soluble hydroxyphenolic compound levels in treated axes were not significantly different from the control at any sampling period. The total soluble amino acid pool showed a general decrease with time in glyphosate‐treated tissues. The phenylalanine pool was lowered with treatment time and the ammonia concentration (per g fr. wt. basis) was increased after treatment. No significant differences were noted in the concentration of soluble protein of glyphosate‐treated tissue when compared to controls. Visual effects (stunting, lack of secondary root formation, and necrotic areas) of glyphosate were more obvious in the root than in the hypocotyl. Analysis of various chemical constituents substantiated that other glyphosate effects were more clearly demonstrable in the root than in the hypocotyl or in the intact axis. On a per root basis glyphosate markedly increased PAL activity while reducing free phenylalanine, free tyrosine, soluble hydroxyphenolics, total free amino acids and ammonia content. The effect of glyphosate in the root was greatest on phenylalanine content, reducing it five‐fold. The results indicate that glyphosate could exert its effect through either induction of PAL activity and/or inhibition of aromatic amino acid synthesis.
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Claims 20
Claim · model-written summary
Glyphosate increased PAL activity in axes of young dark-grown soybean seedlings.
- Taxon
- soybean seedlings
Glycine maxe0 - Organ / stage
- axese0
- Treatment
- glyphosatee0
- Outcome
- phenylalanine ammonia‐lyase (PAL; E.C. 4.3.1.5) activitye0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Amounts of extractable phenylalanine ammonia‐lyase (PAL; E.C. 4.3.1.5) activity increased in the axes of 3–day‐old, dark‐grown soybean seedlings [ Glycine max (L.) Merr.] shortly after the seedlings were transferred to glyphosate [ N ‐(phosphonomethyl)‐glycine] solutions.”
Claim · model-written summary
PAL stimulation was detectable 12 hours after treatment relative to controls.
- Taxon
- soybeanGlycine maxe1
- Treatment
- herbicide‐treated tissuee0
- Outcome
- PAL activitye0
- Direction
- stimulatione0
- Value
- 12 he0
- Comparator
- control tissuee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The stimulation of PAL activity in herbicide‐treated tissue (as compared to control tissue) was detectable as early as 12 h after treatment, whereas growth inhibition (length, fresh weight and dry weight) was not significantly affected until 24 h on a fresh‐weight basis and at 48 h on a dry‐weight basis.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Fresh-weight growth inhibition was not significant until 24 hours after herbicide treatment.
- Taxon
- soybeanGlycine maxe1
- Treatment
- herbicide‐treated tissuee0
- Outcome
- growth inhibitione0
- Direction
- not significantly affectede0
- Value
- 24 he0
- Qualifier
- fresh‐weight basise0
- Comparator
- control tissuee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The stimulation of PAL activity in herbicide‐treated tissue (as compared to control tissue) was detectable as early as 12 h after treatment, whereas growth inhibition (length, fresh weight and dry weight) was not significantly affected until 24 h on a fresh‐weight basis and at 48 h on a dry‐weight basis.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Dry-weight growth inhibition was not significant until 48 hours after herbicide treatment.
- Taxon
- soybeanGlycine maxe1
- Treatment
- herbicide‐treated tissuee0
- Outcome
- growth inhibitione0
- Direction
- not significantly affectede0
- Value
- 48 he0
- Qualifier
- dry‐weight basise0
- Comparator
- control tissuee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The stimulation of PAL activity in herbicide‐treated tissue (as compared to control tissue) was detectable as early as 12 h after treatment, whereas growth inhibition (length, fresh weight and dry weight) was not significantly affected until 24 h on a fresh‐weight basis and at 48 h on a dry‐weight basis.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
PAL activity increased over 12–72 hours in treated axes across three expression bases.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- axese0
- Treatment
- herbicide‐treatede0
- Outcome
- PAL activitye0
- Direction
- increasede0
- Qualifier
- 12–72 he0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“PAL activity increased with time (12–72 h) in herbicide‐treated axes when expressed as activity per gram fresh weight, specific activity, and on a per axis basis.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
PAL stimulation correlated positively with glyphosate concentration.
- Taxon
- soybeanGlycine maxe1
- Treatment
- glyphosate concentratione0
- Outcome
- PAL activity stimulatione0
- Direction
- positivelye0
- Qualifier
- 10 –4 to 10 –3 Me0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“PAL activity stimulation correlated positively with glyphosate concentration from 10 –4 to 10 –3 M .”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Control PAL activity remained nearly constant over 12–72 hours.
- Taxon
- soybeanGlycine maxe1
- Outcome
- PAL activitye0
- Direction
- remained nearly constante0
- Qualifier
- 12–72 he0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“PAL activity in control tissues remained nearly constant over the sampling period (12–72 h).”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Total alcohol-soluble hydroxyphenolic levels in treated axes did not differ significantly from controls.
- Taxon
- soybeanGlycine maxe1
- Treatment
- treated axese0
- Outcome
- Total alcohol‐soluble hydroxyphenolic compound levelse0
- Direction
- not significantly differente0
- Comparator
- controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Total alcohol‐soluble hydroxyphenolic compound levels in treated axes were not significantly different from the control at any sampling period.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Total soluble amino acids generally decreased over time in treated tissues.
- Taxon
- soybeanGlycine maxe1
- Treatment
- glyphosate‐treated tissuese0
- Outcome
- total soluble amino acid poole0
- Direction
- decreasee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The total soluble amino acid pool showed a general decrease with time in glyphosate‐treated tissues.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
The phenylalanine pool decreased with treatment time.
- Taxon
- soybeanGlycine maxe1
- Treatment
- treatmente0
- Outcome
- phenylalanine poole0
- Direction
- lowerede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The phenylalanine pool was lowered with treatment time and the ammonia concentration (per g fr. wt. basis) was increased after treatment.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Ammonia concentration increased after treatment.
- Taxon
- soybeanGlycine maxe1
- Treatment
- treatmente0
- Outcome
- ammonia concentratione0
- Direction
- increasede0
- Qualifier
- per g fr. wt. basise0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The phenylalanine pool was lowered with treatment time and the ammonia concentration (per g fr. wt. basis) was increased after treatment.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Soluble protein concentration did not significantly differ from controls after glyphosate.
- Taxon
- soybeanGlycine maxe1
- Treatment
- glyphosate‐treated tissuee0
- Outcome
- concentration of soluble proteine0
- Direction
- No significant differencese0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“No significant differences were noted in the concentration of soluble protein of glyphosate‐treated tissue when compared to controls.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Glyphosate visual damage was more obvious in roots than hypocotyls.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- roote0
- Treatment
- glyphosatee0
- Outcome
- Visual effects (stunting, lack of secondary root formation, and necrotic areas)e0
- Direction
- more obviouse0
- Comparator
- hypocotyle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Visual effects (stunting, lack of secondary root formation, and necrotic areas) of glyphosate were more obvious in the root than in the hypocotyl.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Glyphosate markedly increased root PAL activity.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- roote0
- Treatment
- glyphosatee0
- Outcome
- PAL activitye0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“On a per root basis glyphosate markedly increased PAL activity while reducing free phenylalanine, free tyrosine, soluble hydroxyphenolics, total free amino acids and ammonia content.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Glyphosate reduced root free phenylalanine.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- roote0
- Treatment
- glyphosatee0
- Outcome
- free phenylalaninee0
- Direction
- reducinge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“On a per root basis glyphosate markedly increased PAL activity while reducing free phenylalanine, free tyrosine, soluble hydroxyphenolics, total free amino acids and ammonia content.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Glyphosate reduced root free tyrosine.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- roote0
- Treatment
- glyphosatee0
- Outcome
- free tyrosinee0
- Direction
- reducinge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“On a per root basis glyphosate markedly increased PAL activity while reducing free phenylalanine, free tyrosine, soluble hydroxyphenolics, total free amino acids and ammonia content.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Glyphosate reduced root soluble hydroxyphenolics.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- roote0
- Treatment
- glyphosatee0
- Outcome
- soluble hydroxyphenolicse0
- Direction
- reducinge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“On a per root basis glyphosate markedly increased PAL activity while reducing free phenylalanine, free tyrosine, soluble hydroxyphenolics, total free amino acids and ammonia content.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Glyphosate reduced root total free amino acids.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- roote0
- Treatment
- glyphosatee0
- Outcome
- total free amino acidse0
- Direction
- reducinge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“On a per root basis glyphosate markedly increased PAL activity while reducing free phenylalanine, free tyrosine, soluble hydroxyphenolics, total free amino acids and ammonia content.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Glyphosate reduced root ammonia content.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- roote0
- Treatment
- glyphosatee0
- Outcome
- ammonia contente0
- Direction
- reducinge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“On a per root basis glyphosate markedly increased PAL activity while reducing free phenylalanine, free tyrosine, soluble hydroxyphenolics, total free amino acids and ammonia content.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
Claim · model-written summary
Glyphosate reduced root phenylalanine content fivefold, its largest root effect.
- Taxon
- soybeanGlycine maxe1
- Organ / stage
- roote0
- Treatment
- glyphosatee0
- Outcome
- phenylalanine contente0
- Direction
- reducinge0
- Value
- five‐folde0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effect of glyphosate in the root was greatest on phenylalanine content, reducing it five‐fold.”
e1“soybean seedlings [ Glycine max (L.) Merr.]”
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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.