Both hydrogen sulfide (H2S) and hydrogen peroxide (H2O2) are separately regarded as a highly reactive molecule involved in root morphogenesis. In this report, corresponding causal link governing lateral root formation was investigated. By using pharmacological, anatomic, and molecular approaches, evidence presented here revealed the molecular mechanism underlying tomato lateral root development triggered by H2S. A H2S donor sodium hydrosulfide (NaHS) triggered the accumulation of H2O2, the up-regulation of RBOH1 transcript, and thereafter tomato lateral root formation. Above responses were sensitive to the H2O2 scavenger (dimethylthiourea; DMTU) and the inhibitor of NADPH oxidase (diphenylene idonium; DPI), showing that the accumulations of H2O2 and increased RBOH1 transcript were respectively prevented. Lateral root primordial and lateral root formation were also impaired. Further molecular evidence revealed that H2S-modulated gene expression of cell cycle regulatory genes, including up-regulation of SlCYCA2;1, SlCYCA3;1, and SlCDKA1, and the down-regulation of SlKRP2, were prevented by the co-treatment with DMTU or DPI. Above mentioned inducing phenotypes were consistent with the changes of lateral root formation-related microRNA transcripts: up-regulation of miR390a and miR160, and with the opposite tendencies of their target genes (encoding auxin response factors). Contrasting tendencies were observed when DMTU or DPI was added together. The occurrence of H2S-mediated S-sulfhydration during above responses was preliminarily discovered. Overall, these results suggested an important role of RBOH1-mediated H2O2 in H2S-elicited tomato lateral root development, and corresponding H2S-target proteins regulated at transcriptional and post-translational levels.

How to use environmentally friendly technology to enhance rice field and grain quality is a challenge for the scientific community. Here, we showed that the application of molecular hydrogen in the form of hydrogen nanobubble water could increase the length, width, and thickness of brown/rough rice and white rice, as well as 1000-grain weight, compared to the irrigation with ditch water. The above results were well matched with the transcriptional profiles of representative genes related to high yield, including up-regulation of heterotrimeric G protein β-subunit gene (RGB1) for cellular proliferation, Grain size 5 (GS5) for grain width, Small grain 1 (SMG1) for grain length and width, Grain weight 8 (GW8) for grain width and weight, and down-regulation of negatively correlated gene Grain size 3 (GS3) for grain length. Meanwhile, although total starch content in white rice is not altered by HNW, the content of amylose was decreased by 31.6%, which was parallel to the changes in the transcripts of the amylose metabolism genes. In particular, cadmium accumulation in white rice was significantly reduced, reaching 52% of the control group. This phenomenon was correlated well with the differential expression of transporter genes responsible for Cd entering plants, including down-regulated Natural resistance-associated macrophage protein (Nramp5), Heavy metal transporting ATPase (HMA2 and HMA3), and Iron-regulated transporters (IRT1), and for decreasing Cd accumulation in grain, including down-regulated Low cadmium (LCD). This study clearly showed that the application of molecular hydrogen might be used as an effective approach to increase field and grain quality of rice.