Abstract: To clarify the effects of trehalose on soil vitality and flue⁃cured tobacco quality，and to address issues such as soil degradation and decreased flue⁃cured tobacco quality caused by long⁃term continuous cropping，using Yunyan 87 as the experimental material，experiments were conducted in long⁃term continuous cropping plots of flue⁃cured tobacco.We set three concentrations of trehalose（79.40，154.64，393.67 mg/L） and three application frequencies（once every 10，15 and 20 days），root irrigation was started 10 days after transplantation and was applied for 3 times in total，soil physicochemical properties，enzyme activity，microbial quantity and diversity，as well as flue⁃cured tobacco chemical composition，aroma causing substances，and disease index were measured at key growth stages of flue⁃cured tobacco.The results showed that the application of 393.67 mg/L trehalose every 15 days significantly improved soil nutrient content，enzyme activity，microbial diversity，and quantity. Among them，the organic matter content increased by 14.54% compared to the control（CK，equal amount of clean water applied every 15 days），soil enzyme activity increased by 15.07%—61.09% compared to CK，and soil microbialrichness index increased by 16.49% compared to CK.The application of 393.67 mg/L trehalose every 10 days had a better effect on the prevention and control of black shank disease，and the application every 15 days had a better effect on the prevention and control of bacterial wilt disease，with disease indices reduced by 6. 82% and 5.76% respectively compared to CK.The application of 393.67 mg/L trehalose every 15 days significantly increased the total sugar and potassium content of middle and upper flue⁃cured tobacco leaves，and promoted the accumulation of aromatic substances in flue⁃cured tobacco leaves.The total amount of aromatic substances in middle and upper flue⁃cured tobacco leaves increased by 30.81% and 31.11% respectively compared to CK.In summary，applying 393.67 mg/L trehalose for root irrigation every 15 days after transplanting flue⁃cured tobacco can significantly increase soil nutrient content and enzyme activity，promote chemical composition coordination and aroma substance accumulation in flue⁃cured tobacco leaves，effectively alleviate the accumulation of soil borne diseases in continuous cropping flue⁃cured tobacco fields，and comprehensively improve flue⁃cured tobacco leaf quality.

Key words: Flue?cured tobacco, Trehalose, Continuous cropping obstacle, Soil physicochemical property, Disease index, Chemical composition, Aromatic substance

摘要： 为明确海藻糖对土壤活力及烤烟品质的影响，解决长期连作引发的土壤退化及烤烟品质下降等问题，以云烟 87为试验材料，在烤烟长期连作地块开展试验。设置 3 个海藻糖质量浓度（79.40、154.64、393.67 mg/L）及3种施用频率（每10、15、20 d 施 1 次），于移栽后10 d开始进行灌根处理，各处理均连续施用3次，并于烤烟关键生育节点测定土壤理化性质、酶活性、微生物数量及多样性，以及烤烟化学成分、致香物质及病情指数等。结果表明，每15 d施用393.67 mg/L海藻糖对土壤养分含量、酶活性、微生物多样性及数量提升效果显著，其中，有机质含量较对照（CK，每15 d施用等量清水）提升14.54%，土壤酶活性较CK提升15.07%~61.09%，土壤微生物丰富度指数较CK提升16.49%。每10 d施用393.67 mg/L海藻糖对黑胫病防控效果较好，每15 d施用对青枯病防控效果较好，其病情指数较CK分别降低6.82%、5.76%。每15 d施用393.67 mg/L海藻糖对中上部烟叶总糖、钾含量提升效果显著，并可促进烟叶致香物质积累，中部及上部烟叶致香物质总量较CK分别提升30.81%、31.11%。综上，烤烟移栽后每15 d用393.67 mg/L 的海藻糖进行灌根处理，能够显著提高土壤养分含量及酶活性，促进烟叶化学成分协调及香气物质积累，有效缓解连作烟田土传病害累积，综合改善烟叶品质。

关键词: 烤烟, 海藻糖, 连作障碍, 土壤理化性质, 病情指数, 化学成分, 致香物质