Effect of low temperature on conductivity change, indicative of cell membrane damage, in cucumber leaves of various ages. (A) ‘Baekbongdadagi’. (B) ‘Jangbaekdadagi’. (C) ‘Kyoulsalicheongjang’. Leaf 1 is the oldest. Values are the mean ±se of three replicates. In some cases, the error bar is obscured by the symbol. FW, fresh weight.