Abstract
The Brazilian cerrado presents strong climate seasonality. During the dry season, plants may be exposed to stressful situations, such as a soil surface water deficit, that stimulate their chemical defenses. However, the seasonality effect on the production of allelopathic compounds of cerrado plant species is poorly understood. In this study, the phytotoxic activities of common native cerrado plants were evaluated during rainy and dry seasons. Crude leaves extracts (10% concentration: weight/volume, with dry leaves and distilled water) from eleven species were tested on lettuce and sesame germination. The negative effects on germination percentages, rates and informational entropies of the target species were higher when submitted to plant extracts from the dry season, where the germination rate was the most sensible parameter. The higher sensibility of lettuce and the germination rate parameter showed this difference. Only two exceptions had higher effects for rainy season extracts; one species showed higher negative effects on germination informational entropy of lettuce and another species on the germination rate of sesame. Thus, increases in the allelopathic activity were seen in the majority of the studied cerrado plant species during the dry season. These distinct responses to stressful situations in a complex environment such as the Brazilian cerrado may support the establishment and survival of some species.
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Claims 6
Claim · model-written summary
Dry-season plant extracts had stronger negative effects on target seed germination percentage, rate, and informational entropy than rainy-season extracts.
- Taxon
- lettuce and sesame
Sesamum indicum
Lactuca sativae1 - Treatment
- plant extracts from the dry seasone0
- Outcome
- germination percentages, rates and informational entropiese0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The negative effects on germination percentages, rates and informational entropies of the target species were higher when submitted to plant extracts from the dry season”
e1“Crude leaves extracts (10% concentration: weight/volume, with dry leaves and distilled water) from eleven species were tested on lettuce and sesame germination”
Claim · model-written summary
Germination rate was the most sensitive measure of the seasonal difference in allelopathic effects.
- Taxon
- lettuce and sesameSesamum indicumLactuca sativae1
- Outcome
- germination ratee0
- Direction
- most sensiblee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“where the germination rate was the most sensible parameter”
e1“Crude leaves extracts (10% concentration: weight/volume, with dry leaves and distilled water) from eleven species were tested on lettuce and sesame germination”
Claim · model-written summary
Lettuce was more sensitive to the plant extracts.
- Taxon
- lettuceLactuca sativae0
- Outcome
- sensibility of lettucee0
- Direction
- highere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The higher sensibility of lettuce and the germination rate parameter showed this difference”
Claim · model-written summary
One species had a stronger negative effect on lettuce germination informational entropy with rainy-season extracts.
- Taxon
- lettuceLactuca sativae0
- Treatment
- rainy season extractse0
- Outcome
- germination informational entropy of lettucee0
- Direction
- higher negative effectse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Only two exceptions had higher effects for rainy season extracts; one species showed higher negative effects on germination informational entropy of lettuce”
Claim · model-written summary
A different species had a stronger negative effect on sesame germination rate with rainy-season extracts.
- Taxon
- sesameSesamum indicume0
- Treatment
- rainy season extractse0
- Outcome
- germination rate of sesamee0
- Direction
- higher effectse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Only two exceptions had higher effects for rainy season extracts; one species showed higher negative effects on germination informational entropy of lettuce and another species on the germination rate of sesame”
Claim · model-written summary
Most studied cerrado species had increased allelopathic activity during the dry season.
Verbatim
e0“increases in the allelopathic activity were seen in the majority of the studied cerrado plant species during the dry season”
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See all 19 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.