Abstract
Background The unique physicochemical properties of soda saline-alkali soils significantly reduce soil nitrogen availability and crop nitrogen use efficiency. While high-yield and high-efficiency cultivation practice offer a key strategy for the synergistic improvement of both crop productivity and resource use efficiency. However, the optimal nitrogen input rate for these practices remains to be determined. Methods Hence, a three-year field study was implemented with nitrogen fertilizer application rates ranging from 0 to 325 kg ha −1 (0, 125, 175, 225, 275, 325 kg ha −1 ) to assess their effects on ionic balance, stress physiology, nitrogen use efficiency, and grain yield in rice grown under soda saline-alkali soil conditions. Results The findings indicate that additional nitrogen fertilizer, particularly at 275 kg ha −1 within the high-yield and high-efficiency cultivation practice, significantly reduced the leaf Na + /K + ratio and levels of superoxide anion (O 2 − ) and malondialdehyde (MDA), while increasing K + concentration and enhancing the levels of soluble proteins and proline, as well as the activities of peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX). Conversely, leaf Na + concentration increased significantly with rising nitrogen application rates. Furthermore, supplementary nitrogen fertilizer significantly improved total nitrogen uptake, nitrogen use efficiency (NUE), and nitrogen agronomic efficiency (NAE) in rice, which can be attributed to markedly enhanced activities of key nitrogen metabolism enzymes. Consequently, grain yields under the N4 (275 kg ha −1 ), N5 (325 kg ha −1 ), N3 (225 kg ha −1 ), N2 (175 kg ha −1 ), and N1 (125 kg ha −1 ) treatments exhibited significant increases of 94.34%, 62.40%, 56.15%, 37.78%, and 24.01%, respectively, relative to the N0 control. These results demonstrate that, within the high-yield and high-efficiency cultivation practice, nitrogen fertilization at a rate of 275 kg ha −1 plays a crucial role in improving rice productivity and optimizing nitrogen use efficiency in soda saline-alkali paddy fields.
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Claims 12
Claim · model-written summary
Additional nitrogen at 275 kg ha−1 significantly reduced leaf Na+/K+ ratio, superoxide anion and MDA levels in rice.
- Taxon
- rice
Oryza sativae1 - Treatment
- additional nitrogen fertilizer, particularly at 275 kg ha −1e3
- Outcome
- leaf Na + /K + ratio and levels of superoxide anion (O 2 − ) and malondialdehyde (MDA)e3
- Direction
- reducede3
- Setting
- three-year field studye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e3“additional nitrogen fertilizer, particularly at 275 kg ha −1 within the high-yield and high-efficiency cultivation practice, significantly reduced the leaf Na + /K + ratio and levels of superoxide anion (O 2 − ) and malondialdehyde (MDA)”
Claim · model-written summary
Additional nitrogen at 275 kg ha−1 increased K+ concentration in rice leaves.
- Taxon
- riceOryza sativae1
- Treatment
- additional nitrogen fertilizer, particularly at 275 kg ha −1e3
- Outcome
- K + concentratione4
- Direction
- increasinge4
- Setting
- three-year field studye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e3“additional nitrogen fertilizer, particularly at 275 kg ha −1 within the high-yield and high-efficiency cultivation practice, significantly reduced the leaf Na + /K + ratio and levels of superoxide anion (O 2 − ) and malondialdehyde (MDA)”
e4“while increasing K + concentration and enhancing the levels of soluble proteins and proline, as well as the activities of peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)”
Claim · model-written summary
Additional nitrogen at 275 kg ha−1 enhanced soluble protein and proline levels in rice leaves.
- Taxon
- riceOryza sativae1
- Treatment
- additional nitrogen fertilizer, particularly at 275 kg ha −1e3
- Outcome
- levels of soluble proteins and prolinee4
- Direction
- enhancinge4
- Setting
- three-year field studye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e3“additional nitrogen fertilizer, particularly at 275 kg ha −1 within the high-yield and high-efficiency cultivation practice, significantly reduced the leaf Na + /K + ratio and levels of superoxide anion (O 2 − ) and malondialdehyde (MDA)”
e4“while increasing K + concentration and enhancing the levels of soluble proteins and proline, as well as the activities of peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)”
Claim · model-written summary
Additional nitrogen at 275 kg ha−1 enhanced POD, CAT and APX activities in rice leaves.
- Taxon
- riceOryza sativae1
- Treatment
- additional nitrogen fertilizer, particularly at 275 kg ha −1e3
- Outcome
- activities of peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)e4
- Direction
- enhancinge4
- Setting
- three-year field studye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e3“additional nitrogen fertilizer, particularly at 275 kg ha −1 within the high-yield and high-efficiency cultivation practice, significantly reduced the leaf Na + /K + ratio and levels of superoxide anion (O 2 − ) and malondialdehyde (MDA)”
e4“while increasing K + concentration and enhancing the levels of soluble proteins and proline, as well as the activities of peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)”
Claim · model-written summary
Leaf Na+ concentration in rice increased significantly with rising nitrogen rates.
- Taxon
- riceOryza sativae1
- Treatment
- rising nitrogen application ratese5
- Outcome
- leaf Na + concentratione5
- Direction
- increasede5
- Setting
- three-year field studye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e5“Conversely, leaf Na + concentration increased significantly with rising nitrogen application rates”
Claim · model-written summary
Supplementary nitrogen fertilizer significantly improved total nitrogen uptake, NUE and NAE in rice.
- Taxon
- riceOryza sativae6
- Treatment
- supplementary nitrogen fertilizere6
- Outcome
- total nitrogen uptake, nitrogen use efficiency (NUE), and nitrogen agronomic efficiency (NAE)e6
- Direction
- improvede6
- Setting
- three-year field studye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e6“supplementary nitrogen fertilizer significantly improved total nitrogen uptake, nitrogen use efficiency (NUE), and nitrogen agronomic efficiency (NAE) in rice”
Claim · model-written summary
Grain yield under N4 (275 kg ha−1) increased by 94.34% relative to the N0 control.
- Taxon
- riceOryza sativae1
- Treatment
- N4 (275 kg ha −1 )e7
- Outcome
- grain yieldse7
- Direction
- increasese7
- Value
- 94.34%e7
- Comparator
- N0 controle7
- Setting
- three-year field studye2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e7“grain yields under the N4 (275 kg ha −1 ), N5 (325 kg ha −1 ), N3 (225 kg ha −1 ), N2 (175 kg ha −1 ), and N1 (125 kg ha −1 ) treatments exhibited significant increases of 94.34%, 62.40%, 56.15%, 37.78%, and 24.01%, respectively, relative to the N0 control”
Claim · model-written summary
Grain yield under N5 (325 kg ha−1) increased by 62.40% relative to the N0 control.
- Taxon
- riceOryza sativae1
- Treatment
- N5 (325 kg ha −1 )e7
- Outcome
- grain yieldse7
- Direction
- increasese7
- Value
- 62.40%e7
- Comparator
- N0 controle7
- Setting
- three-year field studye2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e7“grain yields under the N4 (275 kg ha −1 ), N5 (325 kg ha −1 ), N3 (225 kg ha −1 ), N2 (175 kg ha −1 ), and N1 (125 kg ha −1 ) treatments exhibited significant increases of 94.34%, 62.40%, 56.15%, 37.78%, and 24.01%, respectively, relative to the N0 control”
Claim · model-written summary
Grain yield under N3 (225 kg ha−1) increased by 56.15% relative to the N0 control.
- Taxon
- riceOryza sativae1
- Treatment
- N3 (225 kg ha −1 )e7
- Outcome
- grain yieldse7
- Direction
- increasese7
- Value
- 56.15%e7
- Comparator
- N0 controle7
- Setting
- three-year field studye2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e7“grain yields under the N4 (275 kg ha −1 ), N5 (325 kg ha −1 ), N3 (225 kg ha −1 ), N2 (175 kg ha −1 ), and N1 (125 kg ha −1 ) treatments exhibited significant increases of 94.34%, 62.40%, 56.15%, 37.78%, and 24.01%, respectively, relative to the N0 control”
Claim · model-written summary
Grain yield under N2 (175 kg ha−1) increased by 37.78% relative to the N0 control.
- Taxon
- riceOryza sativae1
- Treatment
- N2 (175 kg ha −1 )e7
- Outcome
- grain yieldse7
- Direction
- increasese7
- Value
- 37.78%e7
- Comparator
- N0 controle7
- Setting
- three-year field studye2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e7“grain yields under the N4 (275 kg ha −1 ), N5 (325 kg ha −1 ), N3 (225 kg ha −1 ), N2 (175 kg ha −1 ), and N1 (125 kg ha −1 ) treatments exhibited significant increases of 94.34%, 62.40%, 56.15%, 37.78%, and 24.01%, respectively, relative to the N0 control”
Claim · model-written summary
Grain yield under N1 (125 kg ha−1) increased by 24.01% relative to the N0 control.
- Taxon
- riceOryza sativae1
- Treatment
- N1 (125 kg ha −1 )e7
- Outcome
- grain yieldse7
- Direction
- increasese7
- Value
- 24.01%e7
- Comparator
- N0 controle7
- Setting
- three-year field studye2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in rice grown under soda saline-alkali soil conditions”
e2“a three-year field study was implemented”
e7“grain yields under the N4 (275 kg ha −1 ), N5 (325 kg ha −1 ), N3 (225 kg ha −1 ), N2 (175 kg ha −1 ), and N1 (125 kg ha −1 ) treatments exhibited significant increases of 94.34%, 62.40%, 56.15%, 37.78%, and 24.01%, respectively, relative to the N0 control”
Claim · model-written summary
Nitrogen fertilization at 275 kg ha−1 is recommended to improve rice productivity and nitrogen use efficiency in soda saline-alkali paddy fields.
- Taxon
- riceOryza sativae0
- Treatment
- nitrogen fertilization at a rate of 275 kg ha −1e0
- Outcome
- rice productivity and optimizing nitrogen use efficiencye0
- Setting
- soda saline-alkali paddy fieldse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“nitrogen fertilization at a rate of 275 kg ha −1 plays a crucial role in improving rice productivity and optimizing nitrogen use efficiency in soda saline-alkali paddy fields”
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