The photosynthetic and structural differences between leaves and siliques of Brassica napus exposed to potassium deficiency

Table 2 Effects of K supply on photosynthetic parameters of light- and CO₂-response curves

Organs	Treatment	A (μmol m⁻² s⁻¹)	g _s (mol m⁻² s⁻¹)	C _i (μmol mol⁻¹)	α	α/Chl (m⁻²/g)	CE	CE/Chl (m⁻²/g)
Leaf	-K	16.8 ± 1.7b¹	0.199 ± 0.009b	264 ± 7a	0.0463 ± 0.0023b	0.1103 ± 0.0054a	0.0604 ± 0.0012b	0.1438 ± 0.0027a
Leaf	+K	23.3 ± 1.1a	0.346 ± 0.012a	234 ± 6b	0.0552 ± 0.0022a	0.0863 ± 0.0034b	0.0811 ± 0.0008a	0.1267 ± 0.0022b
Silique	-K	6.5 ± 0.1b*	0.108 ± 0.009b*	281 ± 4a	0.0184 ± 0.0004b*	0.0921 ± 0.0018a*	0.0304 ± 0.0003b*	0.1521 ± 0.0028a
Silique	+K	8.1 ± 0.3a*²	0.162 ± 0.004a*	297 ± 4a*	0.0212 ± 0.0003a*	0.0663 ± 0.0009b*	0.0411 ± 0.0002a*	0.1285 ± 0.0008b

A, net photosynthetic rate; g _s, stomatal conductance; C _i, substomatal CO₂ concentration; α, apparent quantum yield; α/Chl, apparent quantum yield per chlorophyll concentration; CE, carboxylation efficiency; CE/Chl, carboxylation efficiency per chlorophyll concentration
Data represent mean ± standard error (SE) of four replicates for parameters under light saturation conditions and three replicates for simulation parameters of light- and CO₂-response curves
Different letters indicate statistically significant differences (P < 0.05) between the -K and +K treatments
*Indicates statistically significant differences (P < 0.05) between the two organs under the same treatment conditions

ISSN: 1471-2229