Abstract
Alkalies are important agricultural contaminants complexly affecting plant metabolism. In this study, rice seedlings were subjected to alkaline stress (NaHCO3:Na2CO3 = 9:1; pH 8.9) for 30 days. The results showed that stress mightily reduced net photosynthetic rate (P N), but slightly decreased transpiration rate and stomatal conductance. This indicated that decline of P N might be a result of nonstomatal factors. Alkaline stress caused a large accumulation of Na+ in leaves up to toxic concentration, which possibly affected chloroplast ultrastructure and photosynthesis. We found that alkaline stress reduced chlorophyll fluorescence parameters, such as ratios of Fv'/Fm', Fv/Fm, photosystem (PS) II efficiency, and electron transport rates in rice plants, i.e. it influenced the efficiencies of photon capture and electron transport by PSII. This might be a main reason for the decrease of P N under such conditions. Deficiency of minerals could be another reason for the decline of P N. Alkaline stress lowered contents of N, K, Cu, Zn, P, and Fe in rice plants. In addition, the stress strongly affected metabolism of amino acids. This might be caused by imbalance in carbon metabolism as a result of photosynthesis reduction.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. 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 10
Claim · model-written summary
Alkaline stress reduced net photosynthetic rate in rice seedlings.
- Taxon
- rice
Oryza sativae0 - Treatment
- alkaline stresse0
- Outcome
- net photosynthetic ratee1
- Direction
- reducede1
- Qualifier
- for 30 dayse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“rice seedlings were subjected to alkaline stress (NaHCO3:Na2CO3 = 9:1; pH 8.9) for 30 days”
e1“stress mightily reduced net photosynthetic rate (P N)”
Claim · model-written summary
Alkaline stress slightly decreased transpiration rate and stomatal conductance.
- Taxon
- riceOryza sativae0
- Treatment
- alkaline stresse0
- Outcome
- transpiration rate and stomatal conductancee1
- Direction
- decreasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“rice seedlings were subjected to alkaline stress (NaHCO3:Na2CO3 = 9:1; pH 8.9) for 30 days”
e1“slightly decreased transpiration rate and stomatal conductance”
Claim · model-written summary
Alkaline stress caused sodium accumulation in rice leaves up to a toxic concentration.
- Taxon
- riceOryza sativae0
- Organ / stage
- leavese1
- Treatment
- Alkaline stresse1
- Outcome
- accumulation of Na+ in leavese1
- Direction
- accumulatione1
- Qualifier
- up to toxic concentratione1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“rice seedlings were subjected to alkaline stress”
e1“Alkaline stress caused a large accumulation of Na+ in leaves up to toxic concentration”
Claim · model-written summary
Alkaline stress reduced rice chlorophyll fluorescence parameters and electron transport rates.
- Taxon
- riceOryza sativae0
- Treatment
- alkaline stresse0
- Outcome
- chlorophyll fluorescence parameterse0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“alkaline stress reduced chlorophyll fluorescence parameters, such as ratios of Fv'/Fm', Fv/Fm, photosystem (PS) II efficiency, and electron transport rates in rice plants”
Claim · model-written summary
Alkaline stress reduced rice photosystem II efficiency and electron transport rates.
- Taxon
- riceOryza sativae0
- Treatment
- alkaline stresse0
- Outcome
- photosystem (PS) II efficiency, and electron transport ratese0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“alkaline stress reduced chlorophyll fluorescence parameters, such as ratios of Fv'/Fm', Fv/Fm, photosystem (PS) II efficiency, and electron transport rates in rice plants”
Claim · model-written summary
Alkaline stress lowered N, K and Cu contents in rice.
- Taxon
- riceOryza sativae0
- Treatment
- Alkaline stresse0
- Outcome
- contents of N, K, Cue0
- Direction
- lowerede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Alkaline stress lowered contents of N, K, Cu, Zn, P, and Fe in rice plants”
Claim · model-written summary
Alkaline stress lowered Zn, P and Fe contents in rice.
- Taxon
- riceOryza sativae0
- Treatment
- Alkaline stresse0
- Outcome
- Zn, P, and Fee0
- Direction
- lowerede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Alkaline stress lowered contents of N, K, Cu, Zn, P, and Fe in rice plants”
Claim · model-written summary
Alkaline stress strongly affected amino acid metabolism in rice.
- Taxon
- riceOryza sativae0
- Treatment
- alkaline stresse0
- Outcome
- metabolism of amino acidse1
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“rice seedlings were subjected to alkaline stress”
e1“the stress strongly affected metabolism of amino acids”
Claim · model-written summary
The authors suggested that reduced photosystem II photon capture and electron transport might explain the decrease in net photosynthesis under alkaline stress.
- Taxon
- riceOryza sativae0
- Outcome
- decrease of P Ne1
- Qualifier
- efficiencies of photon capture and electron transport by PSIIe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“rice seedlings were subjected to alkaline stress”
e1“it influenced the efficiencies of photon capture and electron transport by PSII. This might be a main reason for the decrease of P N under such conditions”
Claim · model-written summary
The authors suggested mineral deficiency could also explain the decline in rice net photosynthesis.
- Taxon
- riceOryza sativae0
- Outcome
- decline of P Ne1
- Qualifier
- Deficiency of mineralse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“rice seedlings were subjected to alkaline stress”
e1“Deficiency of minerals could be another reason for the decline of P N”
The same questions in other papers
alkalinity · physiology: ion balance · Oryza sativa (rice)Positive and negative results
1 paper in the same direction as this paper · 1 in the opposite direction
- positive
- negative
alkalinity · nutrient: content · Oryza sativa (rice)Positive and negative results
5 papers in the same direction as this paper · 4 in the opposite direction
- positive
- positive
- positive
6 papers more in this group
See all 10 papers →alkalinity · physiology: photosynthesis · Oryza sativa (rice)Results agree
1 paper in the same direction as this paper
- negative
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.