Fig. 7.

The qRT-PCR expression of the tomato SlMTP genes from root and leaf samples under various metal ion stresses. The reactions were normalized using the β-actin reference gene. The standard deviations have been represented by the error bars from three independent technical replicates. The mean expression levels of three replicates were analyzed with the five heavy metals treatments (Cd²⁺, Co²⁺, Fe²⁺, Mn²⁺ and Zn²⁺) using t-tests (p < 0.05). At the same time, the CK represents control samples which represented by different letters (a, b and c) indicate significant differences among each tested tissues under normal condition. Asterisks indicate significant differences between the treatment samples and the corresponding control samples in roots and leaves. (n = 9, p < 0.05, Student’s t-test).