羊粪和硅藻土对铅胁迫下不同基因型烟草生理特性的影响

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中图分类号：S572 文献标识号：A 文章编号：1001-4942（2025）07-0123-10

AbstractIn this experiment，lead low-enriched tobacco variety Yunyan 87 and high-enriched tobacco variety K326 were used as materials，and five treatments were set as CK（control group），T1（lead 500mg⋅kg-1 ）， T2 （lead 500mg⋅kg-1+ sheep manure 1.33g⋅kg-1 ），T3（lead 500mg⋅kg-1+ diatomite 30g⋅kg-1 ）， T4 （lead 500mg⋅kg-1+ sheep manure 1.33g⋅kg-1+ diatomite 30g⋅kg-1 ）. Through pot experiments，the effects of sheep manure，diatomite and their combining application on physiological characteristics of tobacco leaves under lead stresswere investigated， including fluorescence characteristics of Fv/Fm （maximum photochemical efciency），chlorophyll content， photosynthetic parameters of Pn （net photosynthetic rate），Tr （transpiration rate）and Gs（stomatal conductivity），antioxidant enzyme activity and related substances contents of SOD（superoxide dismutase），MDA（malondialdehyde）and H2O2 （hydrogen peroxide），osmotic adjustment substances contents of proline（Pro）and soluble protein（SP），and root activity. The results showed that，T1 treatment，namely lead stress，could inhibit the physiological activityof tobacco.On the whole，T4 treatment could significantly increase the chlorophyll content，Fv/Fm，Gs，Tr and Pn of Yunyan 87 leaves， significantly increase the Fv/Fm and Tr of K326 leaves. That was， sheep manure + diatomite treatment could significantly promote the photosynthesis of tobacco，and reduce the MDA，Pro， H2O2 and soluble protein content and SOD activityof Yunyan 87 leaves under lead stress at the same time，thus reducing the toxicity of lead stress to tobacco. The treatments of sheep manure， diatomite and sheep manure + diatomite all could improve the vitality of tobacco root system under lead stress.In conclusion，applying appropriate amount of sheep manure + diatomite in the soil could improve the resistance of diferent genotypes of tobacco to lead stress，and contribute to the growth，development and physiological activity of tobacco.

KeywordsTobacco； Lead stress;； Sheep manure； Diatomite; Photosynthetic characteristics； Physiolog-ical characteristics

重金属一般是指密度大于 4.5g⋅cm-3 的金属元素，如铅（Pb）、镉（Cd）、汞（ Hg） 等[]，具有隐蔽性强、来源广、易积累、治理难等特点，可通过多种迁移方式或者媒介进入土壤、大气和水体中[2-4]随着我国农业的快速发展，农田中使用过量的化肥、农药及污水灌溉，导致田间土壤重金属含量超标[5」；汽车排放的尾气和行驶过程中的轮胎磨损也使道路两侧田间重金属含量显著升高；固体垃圾的不规范处理也使土壤环境受到重金属的污染[6]

烟草是一种特殊的叶用经济作物[7]，对铅元素有较强的吸收和富集能力[8]。（剩余17396字）