为探究‘红叶’紫薇（Lagerstroemia indica ‘Pink Velour’）对盐胁迫和碱胁迫的代谢响应机制，对‘红叶’紫薇1年生无性扦插苗分别进行盐胁迫（NaCl，pH=7.02）和碱胁迫（NaHCO₃和Na₂CO₃的Na⁺摩尔比为2∶1，pH=9.52）处理，采用液相色谱质谱（LC-MS）分析叶片代谢组学变化，并比较2个处理组与对照（CK）之间的代谢差异。结果表明：与CK相比，盐处理组共筛选出156个差异代谢物，碱处理组共筛选出176个差异代谢物，2个对比组共有23个差异代谢物，其余均为特有差异代谢物。KEGG富集分析表明，次生代谢产物生物合成、氨基酸代谢、糖类代谢、脂肪酸代谢和植物激素合成是响应盐胁迫和碱胁迫的主要代谢通路；甘氨酸、丝氨酸和苏氨酸合成代谢、ABC转运蛋白和维生素B₆合成代谢是盐胁迫组的特有代谢通路；缬氨酸、亮氨酸、异亮氨酸、精氨酸和脯氨酸生物合成代谢、叶酸合成代谢，以及戊糖和葡萄糖醛酸相互转化和抗坏血酸合成代谢是碱胁迫组的特有代谢通路。这些差异代谢物变化和代谢通路富集可能是紫薇响应盐胁迫和碱胁迫的主要机制。

To explore the metabolic response mechanism of Lagerstroemia indica ‘Pink Velour’ to salt and alkali stresses， one-year-old asexual cottage seedlings were treated to salt stress（NaCl， pH=7.02） and alkali stress（NaHCO₃ and Na₂CO₃， Na⁺ mole ratio 2∶1， pH=9.52） respectively， and the leaves metabolic changes and differences of the two treatment groups and the control group（CK） were analyzed and compared by using liquid chromatography mass spectrometry（LC-MS）. The results showed that 156 and 176 different metabolites were screened in salt and alkali stress group respectively， and 23 different metabolites were screened in both groups， and the rest were unique different metabolites. KEGG enrichment analysis showed that the biosynthesis of secondary metabolites， amino acid metabolism， carbohydrate metabolism， fatty acid metabolism and plant hormone synthesis were main metabolic pathways in response to salt and alkali stress. Glycine， serine and threonine anabolism， ABC transporter protein and Vitamin B₆ anabolism were the unique metabolic pathways in salt stress groups. Biosynthesis of valine， leucine， isoleucine， arginine， proline， folic acid and ascorbic acid， and mutual transformation between pentose and glucuronic were the unique metabolic pathway in alkali stress groups. The changes of different metabolites and enriched metabolic pathways might be the main mechanism of L. indica response to the salt stress and alkali stress.