Conclusions
In current study, we investigated the regulation mechanism of SLs signaling-mediated tillering process in S. alterniflora under different salinity conditions. Our results demonstrated that S. alterniflora produced more tillers in moderate salinity condition, which could partly explain the fast expansion of S. alternifloraat the mesohaline area along the coast of China (Figure 2, Figure 4). Moreover, SLs participated in tiller outgrowth of S. alternifloraby reducing the expression of SaD10 and SaD17 and lead to less SLs production in S. alterniflora roots (Table 1; Figure 6). Importantly, the result of SaD14 and SaD53 expression analysis implied that S. alterniflora grown in 15‰ salinity promote the tillering by inhibiting the SLs perception but activating the downstream pathway regulated by SaD53 (Figure 6). According these results, a schematic diagram of SLs signaling-mediated tillering process in S. alterniflora under different salinity treatments were proposed (Figure 7). Such a regulation mechanism of SL-mediated tillering in S. alterniflora under salt condition may provide a new insight into the mechanism of the fast invasion of S. alterniflora along the coast of China.