Paper · 2025 · Brazilian Journal of Animal and Environmental Research

Allelopathy and cytotoxicity of Conyza bonariensis (L.) Cronq extract in vegetable species

Nadia Carolina Sanabria Verón; Rafael Marani Barbosa; Fanni Petrona Ruiz Samudio; et al.

6
claims
9
verbatim quotes
1
citations
3
research areas
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Open access · cc-by

Abstract

Allelopathic and cytotoxic effects inform possible changes due to changes in growth and can be studied using different plant species. The objective of this work was to evaluate the allelopathic and cytotoxic effect of the aqueous extract of Conyza bonariensis on horticultural species. The experiment was carried out in the Phytotechnics Laboratory at Universidade Estadual de Santa Cruz, Ilhéus, Brazil. Lettuce seeds (Vera) and melon seeds (Ouro) were evaluated in germination tests and phytotoxicity. C. bonariensis leaves, stalk, and flowers were selected and placed in a drying oven at 60 °C for 72 h and then weighed for extract aqueous at concentrations of 1, 3, 5, 7 and 10%. Were evaluated germination test (%), germination speed index (GSI), primary root and shoot length of seedlings. For the cytotoxicity test, the onion model was in five concentrations 0, 0.5; 1; 1.5, and 2% where the mitotic index and cell numbers in the cell division phases (prophase, metaphase, anaphase, telophase) were evaluated. The data were subjected to analysis of variance, and the means compared using Scott-Knott test at 5% probability. The results showed that C. bonariensis aqueous extract did not affect germination, germination speed index, and shoot length in melon, but showed phytotoxic effect on seedlings with decreasing root length. The aqueous extracts of C. bonariensis inhibited seed germination and primary root development and shoot length in lettuce. Chromosome disorganization on the equatorial plane during metaphase and chromosome breakage was observed in the mitotic process of onion roots in C. bonariensis aqueous extract concentrations. Higher concentrations of the extract have allelopathic activity with inhibitory action of cell division.

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 6

Intervention effectobservedoriginal resultno effectmeasured

Claim · model-written summary

Conyza extract did not affect melon germination, germination speed, or shoot length.

Taxon
melonCucumis meloe0
Treatment
C. bonariensis aqueous extracte0
Outcome
germination, germination speed index, and shoot lengthe0
Direction
did not affecte0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Cucumis melo
Cucumis melo · TaxonUSDA photo by Scott Bauer. Image Number K7355-11. · Public domain · Wikimedia Commons ↗

Verbatim

e0

“C. bonariensis aqueous extract did not affect germination, germination speed index, and shoot length in melon”

✓ located verbatim in the source · abstract, characters 1155–1264 · show in text ↑
Intervention effectobservedoriginal resultnegativemeasured

Claim · model-written summary

Conyza extract decreased melon seedling root length.

Taxon
melonCucumis meloe1
Treatment
C. bonariensis aqueous extracte2
Outcome
root lengthe0
Direction
decreasinge0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Cucumis melo
Cucumis melo · TaxonUSDA photo by Scott Bauer. Image Number K7355-11. · Public domain · Wikimedia Commons ↗

Verbatim

e0

“showed phytotoxic effect on seedlings with decreasing root length”

✓ located verbatim in the source · abstract, characters 1270–1335 · show in text ↑
e1

“shoot length in melon”

✓ located verbatim in the source · abstract, characters 1243–1264 · show in text ↑
e2

“The results showed that C. bonariensis aqueous extract did not affect germination”

✓ located verbatim in the source · abstract, characters 1131–1212 · show in text ↑
Intervention effectobservedoriginal resultnegativemeasured

Claim · model-written summary

Conyza extract inhibited lettuce seed germination.

Taxon
lettuceLactuca sativae0
Treatment
aqueous extracts of C. bonariensise0
Outcome
seed germinatione0
Direction
inhibitede0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Lactuca sativa
Lactuca sativa · Taxonen:User:Geographer · CC BY 1.0 · Wikimedia Commons ↗

Verbatim

e0

“The aqueous extracts of C. bonariensis inhibited seed germination and primary root development and shoot length in lettuce”

✓ located verbatim in the source · abstract, characters 1337–1459 · show in text ↑
Intervention effectobservedoriginal resultnegativemeasured

Claim · model-written summary

Conyza extract inhibited lettuce primary root development and shoot length.

Taxon
lettuceLactuca sativae0
Treatment
aqueous extracts of C. bonariensise0
Outcome
primary root development and shoot lengthe0
Direction
inhibitede0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Lactuca sativa
Lactuca sativa · Taxonen:User:Geographer · CC BY 1.0 · Wikimedia Commons ↗

Verbatim

e0

“The aqueous extracts of C. bonariensis inhibited seed germination and primary root development and shoot length in lettuce”

✓ located verbatim in the source · abstract, characters 1337–1459 · show in text ↑
Observationobservedoriginal resultnegativemeasured

Claim · model-written summary

Onion roots exposed to Conyza extract showed chromosome disorganization and breakage.

Taxon
onionAllium cepae0
Organ / stage
rootse0
Treatment
C. bonariensis aqueous extracte0
Outcome
Chromosome disorganization on the equatorial plane during metaphase and chromosome breakagee0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Allium cepa
Allium cepa · TaxonMehdi · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Chromosome disorganization on the equatorial plane during metaphase and chromosome breakage was observed in the mitotic process of onion roots in C. bonariensis aqueous extract concentrations”

✓ located verbatim in the source · abstract, characters 1461–1652 · show in text ↑
Intervention effectobservedoriginal resultnegativemeasured

Claim · model-written summary

Higher extract concentrations inhibited cell division.

Taxon
onionAllium cepae1
Treatment
Higher concentrations of the extracte0
Outcome
cell divisione0
Direction
inhibitorye0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Allium cepa
Allium cepa · TaxonMehdi · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Higher concentrations of the extract have allelopathic activity with inhibitory action of cell division”

✓ located verbatim in the source · abstract, characters 1654–1757 · show in text ↑
e1

“onion roots”

✓ located verbatim in the source · abstract, characters 1592–1603 · show in text ↑

Conyza bonariensis · growth · Lactuca sativa (garden lettuce)Positive and negative results

2 papers: 1 positive, 1 negative or no effect

1 in the opposite direction

  1. positive
See all 2 papers →

botanical · growth · Cucumis melo (muskmelon)Positive and negative results

16 papers: 12 positive, 4 negative or no effect

3 papers in the same direction as this paper · 12 in the opposite direction

  1. positive
  2. positive
  3. positive

12 papers more in this group

See all 16 papers →

botanical · cytology · Allium cepa (onion)Positive and negative results

116 papers: 26 positive, 90 negative or no effect

89 papers in the same direction as this paper · 26 in the opposite direction

  1. positive
  2. positive
  3. positive

112 papers more in this group

See all 116 papers →

botanical · growth · Lactuca sativa (garden lettuce)Positive and negative results

271 papers: 114 positive, 157 negative or no effect

156 papers in the same direction as this paper · 114 in the opposite direction

  1. positive
  2. positive
  3. positive

267 papers more in this group

See all 271 papers →

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.