Synergistic effect of antioxidant system and osmolyte in hydrogen sulfide and salicylic acid crosstalk-induced heat tolerance in maize (Zea mays L.) seedlings

Salicylic acid (SA), is a plant hormone with multifunction that is involved in plant growth, development and the acquisition of stress tolerance. Hydrogen sulfide (H2S) is emerging similar functions, but crosstalk between SA and H2S in the acquisition of heat tolerance is not clear. Our recent study firstly reported that SA treatment enhanced the activity of L-cysteine desulfhydrase (L-DES), a key enzyme in H2S biosynthesis, followed by induced endogenous H2S accumulation, which in turn improved the heat tolerance of maize seedlings.1 In addition, NaHS, a H2S donor, enhanced SA-induced heat tolerance, while its biosynthesis inhibitor DL-propargylglycine (PAG) and scavenger hydroxylamine (HT) weakened SA-induced heat tolerance. Also, NaHS had no significant effect on SA accumulation and its biosynthesis enzymes phenylalanine ammonia lyase (PAL) and benzoic-acid-2-hydroxylase (BA2H) activities, as well as significant difference was not observed in NaHS-induced heat tolerance of maize seedlings by SA biosynt...