滤减UV-B辐射强度对植烟环境小气候要素的影响

摘要

Potted experiment for flue-cured tobacco(Nicotiana tabacum L. )K326 was conducted with 3 different attenuated UV-B radiation treatments. The impacts of different treatments on microclimate factors were analyaed at early maturity stage of flue-tobacco by using ridge regression analysis. The results showed that the diurnal curve of air temperature (Ta), photosynthetic active radiation (PAR) and vapor pressure deficit (VPD) around tobacco leaf increased,and the diurnal curve of Carbon-dioxide concentration (Ca) and air relative humidity (RH) decreased. All treatments inhibited Ca and RH, but promoted Ta, especially in treatment 2. Treatment 3 was helpful for tobacco leaf absorbing and utilizing radiation. To sum, the impacts of UV-B radiation on microclimate factors were different with different attenuated UV-B radiation treatments.%以烤烟(Nicotiana tabacum L.)品种'K326'为试验材料,采用盆栽方法,以覆盖3种不同厚度透明薄膜滤减UV-B辐射的处理方式进行试验.在成熟初期,于试验设定时间点分别测定50cm和150cm高度处烤烟环境小气候要素,应用多元统计岭回归分析方法分析了滤减自然条件下25%(T1)、50%(T2)和65%(T3)的UV-B辐射强度对各要素的影响.结果表明:叶片周围空气温度(Ta)、光合有效辐射(PAR)和饱和水汽压亏缺(VPD)的日变化曲线总体呈上升趋势,而二氧化碳浓度(Ca)、相对湿度(RH)则呈下降趋势.岭回归分析表明,滤减UV-B辐射对植烟环境小气候要素作用显著,具体表现在T1、T2、T3处理对Ca和RH总体上均具有抑制作用,滤减50%的UV-B辐射对叶片周围Ca的抑制作用最大;滤减UV-B辐射对Ta有明显的促进作用,滤减50%的UV-B辐射对Ta促进作用最强;相对于自然条件而言,滤减65%的UV-B辐射更有利于烟叶对辐射能的吸收和利用;T1处理对VPD具有明显的促进作用,T2处理在不同高度上对VPD作用方向不一致,T3处理的抑制效应则表现不明显,即在不同处理的UV-B辐射强度水平下,植烟环境小气候要素对UV-B辐射的响应存在一定的差异.