关键词: 生态特征, 党参, 最大熵模型, 生态适宜区

Abstract: We examined the effects of exogenous ATP treatment on the growth of Brassica campestris seedlings under salt stress, and clarified the roles of signal molecules, hydrogen peroxide (H₂O₂) and calcium ion (Ca²⁺) in the ATP regulation of salt tolerance. The results showed that, compared with the single NaCl treatment, ATP+NaCl treatment decreased the number of dead cells, ROS (O₂^-_· and H₂O₂) content, ion (Ca²⁺, Na⁺, Cl^-) content, MDA content, Na⁺/K⁺ ratio, and relative electrical conductivity. The chlorophyll, proline, soluble sugar content, antioxidant enzyme (SOD, POD, CAT, APX) activity, transcriptional regulation of antioxidant enzyme genes (CAT, SOD, APX, GR), NADPH oxidase genes (RBOHD, RBOHF), P5CS1 gene, MAPK kinase genes (MAPK3, MAPK6), and salt tolerance genes (NHX1, SOS1) were all elevated. Compared with ATP+NaCl treatment, the relative electrical conductivity, MDA, chlorophyll, proline, soluble sugar, the activities of antioxidant enzymes (SOD, POD, CAT, APX), and the expression of the above genes were decreased when treated with ATP+NaCl+inhibitors (DPI, DMTU and EGTA). These results indicated that exogenous ATP application could increase cell activity, ROS content, ion content, chlorophyll content, osmotic regulator, antioxidant enzyme activity and related gene expression in B. campestris under salt stress. In addition, signal molecules of H₂O₂ and Ca²⁺ were involved in the ATP regulation of enhancing salt tolerance in B. campestris.

Key words: ecological suitable region, ecological characteristics., maximum entropy model, Codonopsis pilosula