Abstract
Nitrogen (N) and exogenous melatonin (MT) have been demonstrated to effectively mitigate drought stress. However, the regulatory mechanisms underlying their interactive effects on post-anthesis drought responses in wheat remain unclear. This study explored the impacts of N and MT on photosynthesis, plant water relations, antioxidant defense system, N metabolism and remobilization, root architecture, yield, and water and N use efficiency. Compared with drought stress (DS), the co-application of 260 kg N hm -2 (N2) and 100 µmol·L -1 MT (M1) markedly increased the leaf photosynthetic rate root vitality, and root hydraulic conductivity. Under N2 conditions, MT treatment further enhanced the activities of superoxide dismutase, peroxidase, catalase, and glutathione reductase, as well as the contents of proline and betaine, thereby improving antioxidant capacity and cell membrane stability, as evidenced by the lower levels of superoxide anion and malondialdehyde. Additionally, N2 enhanced the regulatory effect of M1 on N metabolism, as evidenced by higher activities of nitrate reductase, glutamine synthetase, glutamate dehydrogenase, and elevated free amino acids content. Compared with DS, N2M1 treatment increased aboveground N accumulation and the contribution of pre-anthesis N translocation to grain N by 30.8% and 11.1%, respectively, resulting in a 20.4% increase in wheat yield. The higher water use efficiency for grain and biomass was mainly attributed to the increased root density and root hydraulic conductivity in the deep soil layer. N use efficiency increased with the rise in MT concentration, particularly under the N1 conditions. Collectively, appropriate N augmentation combined with MT can enhance drought tolerance in wheat, representing a promising cultivation management strategy to mitigate the adverse effects of post-anthesis drought.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by-nc. 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 11
Claim · model-written summary
Combined nitrogen and melatonin increased wheat leaf photosynthetic rate, root vitality, and root hydraulic conductivity relative to drought stress.
- Taxon
- wheat
Triticum aestivumt0 - Treatment
- co-application of 260 kg N hm -2 (N2) and 100 µmol·L -1 MT (M1)e0
- Outcome
- leaf photosynthetic rate root vitality, and root hydraulic conductivitye0
- Direction
- increasede0
- Comparator
- drought stress (DS)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Compared with drought stress (DS), the co-application of 260 kg N hm -2 (N2) and 100 µmol·L -1 MT (M1) markedly increased the leaf photosynthetic rate root vitality, and root hydraulic conductivity”
t0“wheat”
Claim · model-written summary
Under N2, melatonin enhanced four antioxidant enzyme activities.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- MT treatmente0
- Outcome
- activities of superoxide dismutase, peroxidase, catalase, and glutathione reductasee0
- Direction
- enhancede0
- Comparator
- N2 conditionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Under N2 conditions, MT treatment further enhanced the activities of superoxide dismutase, peroxidase, catalase, and glutathione reductase”
t0“wheat”
Claim · model-written summary
Under N2, melatonin enhanced proline and betaine content.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- MT treatmente1
- Outcome
- contents of proline and betainee0
- Direction
- enhancede1
- Comparator
- N2 conditionse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“as well as the contents of proline and betaine, thereby improving antioxidant capacity and cell membrane stability”
e1“Under N2 conditions, MT treatment further enhanced”
t0“wheat”
Claim · model-written summary
The treatment improved antioxidant capacity and cell membrane stability.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- MT treatmente1
- Outcome
- antioxidant capacity and cell membrane stabilitye0
- Direction
- improvinge0
- Comparator
- N2 conditionse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“thereby improving antioxidant capacity and cell membrane stability, as evidenced by the lower levels of superoxide anion and malondialdehyde”
e1“Under N2 conditions, MT treatment further enhanced”
t0“wheat”
Claim · model-written summary
Under N2, M1 increased nitrate reductase, glutamine synthetase, and glutamate dehydrogenase activities.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- M1e0
- Outcome
- activities of nitrate reductase, glutamine synthetase, glutamate dehydrogenasee0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N2 enhanced the regulatory effect of M1 on N metabolism, as evidenced by higher activities of nitrate reductase, glutamine synthetase, glutamate dehydrogenase, and elevated free amino acids content”
t0“wheat”
Claim · model-written summary
Under N2, M1 elevated free amino acids content.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- M1e0
- Outcome
- free amino acids contente0
- Direction
- elevatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N2 enhanced the regulatory effect of M1 on N metabolism, as evidenced by higher activities of nitrate reductase, glutamine synthetase, glutamate dehydrogenase, and elevated free amino acids content”
t0“wheat”
Claim · model-written summary
N2M1 increased aboveground nitrogen accumulation by 30.8%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- N2M1 treatmente0
- Outcome
- aboveground N accumulatione0
- Direction
- increasede0
- Value
- 30.8%e0
- Comparator
- DSe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Compared with DS, N2M1 treatment increased aboveground N accumulation and the contribution of pre-anthesis N translocation to grain N by 30.8% and 11.1%, respectively”
t0“wheat”
Claim · model-written summary
N2M1 increased the contribution of pre-anthesis nitrogen translocation to grain nitrogen by 11.1%.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- N2M1 treatmente0
- Outcome
- contribution of pre-anthesis N translocation to grain Ne0
- Direction
- increasede0
- Value
- 11.1%e0
- Comparator
- DSe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Compared with DS, N2M1 treatment increased aboveground N accumulation and the contribution of pre-anthesis N translocation to grain N by 30.8% and 11.1%, respectively”
t0“wheat”
Claim · model-written summary
N2M1 increased wheat yield by 20.4%.
- Taxon
- wheatTriticum aestivume0
- Treatment
- N2M1 treatmente1
- Outcome
- wheat yielde0
- Direction
- increasee0
- Value
- 20.4%e0
- Comparator
- DSe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“resulting in a 20.4% increase in wheat yield”
e1“Compared with DS, N2M1 treatment”
e2“wheat yield”
Claim · model-written summary
Water use efficiency for grain and biomass was higher, attributed to increased deep root density and hydraulic conductivity.
- Taxon
- wheatTriticum aestivumt0
- Outcome
- water use efficiency for grain and biomasse0
- Direction
- highere0
- Qualifier
- increased root density and root hydraulic conductivity in the deep soil layere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The higher water use efficiency for grain and biomass was mainly attributed to the increased root density and root hydraulic conductivity in the deep soil layer”
t0“wheat”
Claim · model-written summary
Nitrogen use efficiency increased with melatonin concentration, particularly under N1.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- MT concentratione0
- Outcome
- N use efficiencye0
- Direction
- increasede0
- Qualifier
- particularly under the N1 conditionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N use efficiency increased with the rise in MT concentration, particularly under the N1 conditions”
t0“wheat”
The same questions in other papers
melatonin · physiology: osmolytes · Triticum aestivum (wheat)Results differ
8 papers in the same direction as this paper · 1 in the opposite direction
- positive
- no effect
- positive
6 papers more in this group
See all 10 papers →melatonin · physiology: photosynthesis · Triticum aestivum (wheat)Results differ
17 papers in the same direction as this paper
- positive
- positive
- positive
14 papers more in this group
See all 18 papers →melatonin · physiology: antioxidant enzymes · Triticum aestivum (wheat)Results agree
20 papers in the same direction as this paper
- positive
- positive
- positive
17 papers more in this group
See all 21 papers →melatonin · physiology: oxidative · Triticum aestivum (wheat)Results agree
22 papers in the same direction as this paper
- positive
- positive
- positive
19 papers more in this group
See all 23 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.