3.1 | Changes in growing S. miltiorrhizaseedlings
Abiotic stress is not conducive to the growth of S. miltiorrhizaseedlings, among which P, synergistic stresses of drought and nitrogen deficiency (DN), synergistic stresses of drought, nitrogen deficiency and phosphorus deficiency (DNP) and synergistic stresses of drought, high-temperature, nitrogen deficiency and phosphorus deficiency (DTNP) stresses reached a significant level (p <0.05). P, DN, synergistic stresses of drought, high-temperature and nitrogen deficiency (DTN), synergistic stresses of drought high-temperature and phosphorus deficiency (DTP), DNP, synergistic stresses of high-temperature, nitrogen deficiency and phosphorus deficiency (TNP), and DTNP stresses significantly inhibited the fresh weight of aboveground parts of S. miltiorrhiza (p <0.05) (Figure 1). Drought or synergistic stresses of drought and high-temperature exacerbated the plant growth inhibition of nitrogen deficiency, but not significantly. (e.g., DN and DTN stresses) (Figure 1-a). Drought or high-temperature or synergistic stresses of drought and high-temperatures alleviated the plant growth inhibition of phosphorus deficiency, but not significantly. (e.g., DP, TP, and DTP stresses) (Figure 1-b). Synergistic stresses of drought and high-temperatures aggravated the plant growth inhibition of nitrogen and phosphorus deficiency (e.g., DTNP stresses) (p <0.05) (Figure 1-c). The synergistic stresses of drought and high-temperatures exacerbated the effects of single-factor inhibition, but not to a significant extent (e.g., DT stress) (Figure 1-d).