TMTM influences plant growth under sulfur deficiency
Since TMTM contains sulfur, we tested the effect of the volatile onArabidopsis plants. Five days-old seedlings were transferred to MGRL agar medium with either high sulfate (HS, control) or low sulfate (LS) before the application of 0, 10, 100, 1000 µg TMTM (Table 2). After 7 days, the fresh and dry weights of the total seedlings, the shoots and the roots were analyzed. Figure 3 shows the effects of TMTM on the weights of seedlings grown under LS in comparison to seedlings grown sufficient sulfur in the medium (HS). In all instances, TMTM had the strongest growth promoting effect for seedlings grown on LS supplemented with 10 or 100 µg TMTM (Figure 3). The high dose of 1000 µg TMTM reduced plant growth. In summary, low doses of TMTM (10 - 100 µg) had positive effects on plant fresh and dry weights under sulfur deficiency, while the higher dose (1000 µg) had a negative effect.
We also tested whether TMTM promoted growth of seedlings which were grown on medium with sufficient sulfur (cf. Methods and Materials). Different doses of pure TMTM were applied to 10-days old seedlings grown on HS medium in desiccator for 1 or 2 weeks. Although the same trend was visible, the growth promoting effect of the volatile was not significant (data not shown).