Abstract
Plants in nutrient-poor habitats converge towards lower rates of leaf net CO2 assimilation (Aarea); however, they display variability in leaf mass investment per area (LMA). How a plant optimizes its leaf internal carbon investment may have knock-on effects on structural traits and, in turn, affect leaf carbon fixation. Quantitative models were applied to evaluate the structural causes of variations in LMA and their relevance to Aarea in rapeseed (Brassica napus) based on their responses to nitrogen (N), phosphorus (P), potassium (K), and boron (B) deficiencies. Leaf carbon fixation decreased in response to nutrient deficiency, but the photosynthetic limitations varied greatly depending on the deficient nutrient. In comparison with Aarea, the LMA exhibited diverse responses, being increased under P or B deficiency, decreased under K deficiency, and unaffected under N deficiency. These variations were due to changes in cell- and tissue-level carbon investments between cell dry mass density (N or K deficiency) and cellular anatomy, including cell dimension and number (P deficiency), or both (B deficiency). However, there was a conserved pattern independent of nutrient-specific limitations-low nutrient availability reduced leaf carbon fixation but increased carbon investment in non-photosynthetic structures, resulting in larger but fewer mesophyll cells with a thicker cell wall but a lower chloroplast surface area appressed to the intercellular airspace, which reduced the mesophyll conductance and feedback-limited Aarea. Our results provide insight into the importance of mineral nutrients in balancing the leaf carbon economy by coordinating leaf carbon assimilation and internal distribution.
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 13
Claim · model-written summary
Nutrient deficiency decreased leaf carbon fixation.
Not reportedComparator
Verbatim
e0“Leaf carbon fixation decreased in response to nutrient deficiency”
e1“rapeseed (Brassica napus)”
Claim · model-written summary
Photosynthetic limitations differed by deficient nutrient.
Verbatim
e0“photosynthetic limitations varied greatly depending on the deficient nutrient”
e1“rapeseed (Brassica napus)”
Claim · model-written summary
Phosphorus deficiency increased leaf mass per area.
Not reportedComparator
Verbatim
e0“LMA exhibited diverse responses, being increased under P or B deficiency”
e1“rapeseed (Brassica napus)”
e2“cellular anatomy, including cell dimension and number (P deficiency)”
Claim · model-written summary
Boron deficiency increased leaf mass per area.
Not reportedComparator
Verbatim
e0“LMA exhibited diverse responses, being increased under P or B deficiency”
e1“rapeseed (Brassica napus)”
Claim · model-written summary
Potassium deficiency decreased leaf mass per area.
Not reportedComparator
Verbatim
e0“decreased under K deficiency”
e1“LMA exhibited diverse responses”
e2“rapeseed (Brassica napus)”
Claim · model-written summary
Nitrogen deficiency did not change leaf mass per area.
Not reportedComparator
Verbatim
e0“unaffected under N deficiency”
e1“LMA exhibited diverse responses”
e2“rapeseed (Brassica napus)”
Claim · model-written summary
Under nitrogen or potassium deficiency, leaf mass variations reflected changes in cell dry mass density.
Verbatim
e0“variations were due to changes in cell- and tissue-level carbon investments between cell dry mass density (N or K deficiency)”
e1“rapeseed (Brassica napus)”
Claim · model-written summary
Under phosphorus deficiency, leaf mass variations reflected cellular dimensions and numbers.
Verbatim
e0“cellular anatomy, including cell dimension and number (P deficiency)”
e1“These variations were due to changes in cell- and tissue-level carbon investments”
e2“rapeseed (Brassica napus)”
Claim · model-written summary
Under boron deficiency, leaf mass variations reflected both cell density and anatomy.
Verbatim
e0“or both (B deficiency)”
e1“cell dry mass density (N or K deficiency) and cellular anatomy”
e2“rapeseed (Brassica napus)”
Claim · model-written summary
Low nutrient availability increased investment in non-photosynthetic structures.
- Taxon
- rapeseede1
- Treatment
- low nutrient availabilitye0
- Outcome
- carbon investment in non-photosynthetic structurese0
- Direction
- increasede0
Not reportedComparator
Verbatim
e0“low nutrient availability reduced leaf carbon fixation but increased carbon investment in non-photosynthetic structures”
e1“rapeseed (Brassica napus)”
Claim · model-written summary
Low nutrient availability produced larger but fewer mesophyll cells and thicker cell walls.
- Taxon
- rapeseede2
- Treatment
- low nutrient availabilitye1
- Outcome
- larger but fewer mesophyll cells with a thicker cell walle0
Not reportedComparatorDirection
Verbatim
e0“larger but fewer mesophyll cells with a thicker cell wall”
e1“low nutrient availability”
e2“rapeseed (Brassica napus)”
Claim · model-written summary
Low nutrient availability lowered chloroplast surface area facing intercellular airspace.
- Taxon
- rapeseede2
- Treatment
- low nutrient availabilitye1
- Outcome
- chloroplast surface area appressed to the intercellular airspacee0
- Direction
- lowere0
Not reportedComparator
Verbatim
e0“lower chloroplast surface area appressed to the intercellular airspace”
e1“low nutrient availability”
e2“rapeseed (Brassica napus)”
Claim · model-written summary
Reduced chloroplast surface area lowered mesophyll conductance and limited photosynthesis.
Verbatim
e0“lower chloroplast surface area appressed to the intercellular airspace, which reduced the mesophyll conductance and feedback-limited Aarea”
e1“rapeseed (Brassica napus)”
The same questions in other papers
nitrogen · growth · Brassica napus (oilseed rape)Positive and negative results
16 papers in the same direction as this paper · 65 in the opposite direction
This paper is about lacking the nutrient, so it counts the other way round here.
- positive
- positive
- positive
78 papers more in this group
See all 82 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.