不同保护剂对烤烟叶片日灼伤害的活性氧系统及内源激素的影响

Effects of Different Protective Agents on Reactive Oxygen System and Endogenous Hormones in Sunburned Flue-Cured Tobacco Leaves

为探明不同保护剂对烤烟叶片日灼伤害的防治作用,本试验采用日灼模拟方式对烤烟叶片分别喷施清水、0.1%黄腐酸钾(T1)、56 mg·L^(-1)硫氢化钠(T2)、75 mg·L^(-1)水滴破除剂(T3)和0.2%商品防晒剂(T4)后进行强光(2000μmol·m^(-2)·s^(-1))处理并进行大田防效应用试验,研究其对叶片温度、活性氧含量、抗氧化酶活性、相关激素含量及烤后烟经济性状的影响。结果表明,与喷施清水后强光处理(CK2)相比,叶面喷施黄腐酸钾显著降低叶片温度2.36℃;叶面喷施保护剂整体上显著提高SOD、CAT、POD活性,T1~T4处理SOD活性增幅为17.68%~48.54%,T2~T4处理CAT活性增幅为48.29%~81.39%,T1~T4处理POD活性增幅为4.50%~22.18%;叶面喷施保护剂诱导ABA和JA含量显著降低,降幅分别为34.29%~71.43%和9.15%~60.31%。田间叶面喷施保护剂较喷施清水可降低烟株灼伤率及灼伤指数,两者降幅分别为33.40%~60.00%和11.38%~66.47%;可提升烤后烟产量、产值、均价、上等烟比例和上中等烟比例,增幅依次为2.33%~6.91%、0.42%~1.36%、3.08%~8.38%、0.47%~5.06%和1.85%~4.39%。综上,本试验所用保护剂均可通过调控烟叶抗氧化酶活性和激素ABA、JA含量来提高烟叶对强光的抗性,以喷施75 mg·L^(-1)水滴破除剂保护效果最优。本研究可为烟叶日灼的防治提供理论依据,为日灼保护剂在生产上的应用提供技术支撑。

In order to explore the preventive effects of different protective agents on sunburn injury of flue-cured tobacco leaves,this experiment was conducted using sunburn simulation method through treating with strong light(2000μmol·m^(-2)·s^(-1))after spraying clean water,0.1%potassium fulvate(T1),56 mg·L^(-1)sodium hydrosulfide(T2),75 mg·L^(-1)water droplet breaker(T3)and 0.2%commercial sunscreen(T4)on tobacco leaves,respectively.The field test was carried out to research their effects on leaf temperature,reac-tive oxygen content,antioxidase activity,related hormone content and economic characters of cured tobacco.The results showed that compared with spraying clean water before treating with strong light(CK2),spraying potassium fulvate significantly reduced leaf temperature by 2.36℃.Spraying protective agents on leaves signif-icantly increased the activities of SOD,CAT and POD as a whole,among which,SOD activity increased by 17.68%~48.54%in T1~T4 treatments,CAT activity increased by 48.29%~81.39%in T2~T4 treatments and POD activity increased by 4.50%~22.18%in T1~T4 treatments.Spraying protective agents on leaves sig-nificantly reduced ABA and JA contents,and the decrease rates were 34.29%~71.43%and 9.15%~60.31%,respectively.Compared with spraying clean water,spraying protective agents on leaves could reduce the burn rate and burn index of tobacco plants by 33.40%~60.00%and 11.38%~66.47%,and increase the yield,output value,average price,proportion of superior tobacco and proportion of upper and middle tobacco after cured by 2.33%~6.91%,0.42%~1.36%,3.08%~8.38%,0.47%~5.06%and 1.85%~4.39%,respective-ly.To sum up,the protective agents used in this experiment could improve the resistance of tobacco leaves to strong light by regulating the activities of antioxidant enzymes and the contents of ABA and JA,and spraying 75 mg·L^(-1)water droplet breaker had the best protective effect.This study could provide theoretical basis for the control of tobacco sunburn injury,and provide technical support for the application of sunburn protection agent in production.