Dibutyl Dithiophosphate Increases Radish and Bush Beans Growth

Hydrogen sulfide (H 2 S) is a gasotransmitter that can promote growth and protect plants from environmental stressors. In this study, we tested the impact of dibutyl dithiophosphate (DBDTP), which releases H 2 S as it is metabolized by plants, upon radish and bush bean growth. Experiments examined applications of DBDTP as a seed treatment in combination with soil drenches, and as a foliar spray under greenhouse and field conditions. In greenhouse trials, one application of 12.5 mM DBDTP as a seed treatment plus three applications of 0.5 mM DBDTP as a soil drench increased radish fresh and dry weight by 4%. Under field conditions, seed treatment using a solution of 12.5 or 25 mM DBDTP increased radish plant biomass by 5% to 7%, while radish root fresh weight was increased by 7.3% and 12.4%, respectively. We also examined the phytotoxicity of DBDTP foliar sprays and found that 0.5 mM DBDTP led to foliar damage at 8 and 15 d after germination. Bush bean seeds were treated with DBDTP at 12.5 mM, 25 mM, and 50 mM concentrations leading to trends of increased fresh weight and pod fresh weight. Our results suggest that DBDTP shows potential as an H 2 S donor to enhance plant growth as a seed treatment. However, the mixed responses in seed treatments and the observed foliar phytotoxicity indicate that further research is required before broad use in agricultural settings can be recommended.