Effects of Trehalose on the Physicochemical Properties of Soil and Flue-cured Tobacco Leaf Quality under Tobacco Continuous Cropping

Wang Binjie; Zhang Yuehua; Yang Xue; Wang Dong; Zhang Mingjin; Ma Junkuan; Yan Min; Mao Min; Li Yanqiang; Zhang Liang; Luo Dongsheng; Zhu Guozhi; Qian Yu; Jing Yanqiu

doi:10.15933/j.cnki.1004-3268.2026.07.009

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 microbial richness 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.