Fig. 2
Physiological indicators and correlation analysis of potato leaves. (a) Measurement of photosynthetic data of potato leaves after proper low-temperature treatment for 48 days. (b) Changes in the chlorophyll content, relative conductivity and MDA content in leaves of two potato varieties under low-temperature treatment. (c) Changes in SOD activity and POD activity in the leaves of two potato varieties under low-temperature treatment. (d) Correlation analysis of physiological indexes of potato leaves. The red color represents a positive correlation, and the blue color represents a negative correlation. REC means relative conductivity; Chl means chlorophyll; Fn means net photosynthetic rate, Gs means stomatal conductance; Ci means intercellular CO2 concentration; Tr means Transpiration rate. The data are the mean ± SD; n = 3; the larger the value, the more significant it is (P < 0.05)