Fig. 11From: Exogenous melatonin improves the salt tolerance of cotton by removing active oxygen and protecting photosynthetic organsPrincipal component analysis (PCA) of 18 aboveground traits. Clockwise, the abbreviations stand for: LAX leaf area of xylem, LAP leaf area of phloem, Pro proline, SN stomatal number, PT palisade tissue thickness, Na+ sodium ion, NPQ non-photochemical quenching, H2O2 hydrogen peroxide, \( {O}_2^{\cdotp -} \) superoxide anion, ST spongy tissue thickness, K+ potassium ion, SPT stem phloem thickness, TDW total dry weight, Pn the net photosynthetic rate, SPAD SPAD value, SXT stem xylem thickness, Fv/Fm the maximum photochemical efficiency of PSII, SA stomatal apertureBack to article page