Abstract
Agricultural intensification has led to an elevated use of pesticides and fertilizers such as urea, without considering the negative effects these products can cause, such as acidification of the soil and the entry of lead (Pb) into the trophic chain. The objective of this research was to determine the effect of urea on the absorption of lead (Pb) in the leaf structure of corn (Zea mays L.), spinach (Spinacia oleracea L.), and cabbage (Brassica oleracea L.). These three plant species were exposed to five different concentrations of urea and a constant concentration of Pb in the form of Pb acetate for 93 days. The effect of urea and Pb was determined through analysis of the leaf structure. The results showed an increase in the dry weight of corn, whereas in spinach (T4) (1.5 g urea kg-1 of soil plus 0.5 g Pb kg-1 of soil) dry weight decreased as well as the fresh weight and foliar area. An increase in the chlorophyll index in corn, spinach, and cabbage was observed in the treatments with urea, and there was an influence on soil acidification. We also observed that spinach concentrated more Pb (T4) in its foliage at higher rates of N application. The idiosyncratic nature of the crop combined effects of Pb and N highlights the need for more research on this subject.
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Claims 8
Claim · model-written summary
Corn dry weight increased under the tested urea and Pb exposure.
- Taxon
- corn
Zea mays subsp. mayse0 - Treatment
- ureat0
- Outcome
- dry weighte0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results showed an increase in the dry weight of corn”
t0“urea”
t1“urea”
Claim · model-written summary
Spinach dry weight decreased under T4.
- Taxon
- spinach
Spinacia oleraceae0 - Treatment
- 1.5 g urea kg-1 of soil plus 0.5 g Pb kg-1 of soile0
- Outcome
- dry weighte0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in spinach (T4) (1.5 g urea kg-1 of soil plus 0.5 g Pb kg-1 of soil) dry weight decreased as well as the fresh weight and foliar area”
Claim · model-written summary
Spinach fresh weight and foliar area decreased under T4.
- Taxon
- spinachSpinacia oleraceae0
- Treatment
- 1.5 g urea kg-1 of soil plus 0.5 g Pb kg-1 of soile0
- Outcome
- fresh weight and foliar areae0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in spinach (T4) (1.5 g urea kg-1 of soil plus 0.5 g Pb kg-1 of soil) dry weight decreased as well as the fresh weight and foliar area”
Claim · model-written summary
Urea increased the chlorophyll index in corn.
- Taxon
- cornZea mays subsp. mayse0
- Treatment
- ureae0
- Outcome
- chlorophyll indexe0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An increase in the chlorophyll index in corn, spinach, and cabbage was observed in the treatments with urea”
Claim · model-written summary
Urea increased the chlorophyll index in spinach.
- Taxon
- spinachSpinacia oleraceae0
- Treatment
- ureae0
- Outcome
- chlorophyll indexe0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An increase in the chlorophyll index in corn, spinach, and cabbage was observed in the treatments with urea”
Claim · model-written summary
Urea increased the chlorophyll index in cabbage.
- Taxon
- cabbage
Brassica oleracea var. capitatae0 - Treatment
- ureae0
- Outcome
- chlorophyll indexe0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An increase in the chlorophyll index in corn, spinach, and cabbage was observed in the treatments with urea”
Claim · model-written summary
Urea treatments influenced soil acidification.
- Outcome
- soil acidificatione0
Not reportedTaxon
Verbatim
e0“there was an influence on soil acidification”
Claim · model-written summary
Spinach accumulated more foliage Pb at higher N application rates under T4.
- Taxon
- spinachSpinacia oleraceae0
- Organ / stage
- foliagee0
- Treatment
- higher rates of N applicatione0
- Outcome
- concentrated more Pbe0
- Direction
- moree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“spinach concentrated more Pb (T4) in its foliage at higher rates of N application”
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See all 748 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.