Activation of the ascorbate-glutathione cycle by nitric oxide: signaling under stress conditions induced by arsenic

摘要

The study evaluated the effect of nitric oxide (NO) in Pistia stratiotes exposed to arsenic (As), with NOsupplied in the form of SNP. Plants were exposed to four treatments: control, SNP (0.1 mg L-1), As (1.5 mg L-1)and As + SNP (1.5 and 0.1 mg L-1, respectively), for 24 h. In plants exposed only to As, changes was observed inthe concentration of reduced ascorbate. The addition of SNP altered the concentration of reduced ascorbate,dehydroascorbate and enzymes APX, DHAR and GR, indicating activation of ascorbate-glutathione cycle.