砷胁迫对不同烟草品种光合色素和叶绿素荧光特性的影响

为了研究不同浓度砷(As)对烟草光合色素和叶绿素荧光特性的影响,首先将3个烟草品种翠碧1号、K326和云烟-87幼苗种植在从0到100 mg·kg-1亚砷酸钠(Na As O2)的6个浓度组中进行盆栽试验,并定期进行烟草受害症状的观测,测定叶片的光合色素含量、叶绿素荧光参数。结果表明:烟草在As胁迫下的反应因As胁迫浓度、胁迫时间和烟草品种而异。烟草光合色素含量、叶绿素荧光参数均表现为低浓度下有促进效应和高浓度下有抑制效应,同时3种烟草在40 mg·kg-1As浓度处理下出现生长受阻,且浓度越高胁迫症状越明显。K326和云烟-87表观症状较明显,对As毒害的敏感性高于翠碧1号。随着As胁迫时间的延长,烟草的耐性增强,对As胁迫的敏感性减弱。

Influence of Arsenic Stress on the Photosynthetic Pigments and Chlorophyll Fluorescence Characteristics of Different Tobacco Cultivars

In order to study the influence of different concentrations of arsenic on the photosynthetic pigments and chlorophyll fluorescence characteristics of tobaccos three tobacco cultivars including , K326 and Yunyan 87 were pot-planted and treated with six varied concentrations of sodium arsenite solutions, ranging from 0 to 100 mg·kg^-1. Leaf photosynthetic pigment contents and chlorophyll fluorescence parameters were determined, and harmful symptoms of tobaccos were observed at regular intervals.The results showed that the response of tobacco to arsenic stress varies according to arsenic concentrations, treated time and tobacco cultivars; leaf photosynthetic pigment contents and chlorophyll fluorescence parameters are enhanced at the condition of low arsenic concentrations, and inhibited at the condition of high arsenic concentrations; the growth of three tobacco cultivars is inhibited when treated with 40 mg·kg^-1 arsenic concentration, and the higher the arsenic concentration, the more obvious the symptoms of arsenic stress. The harmful symptoms of K326 and Yunyan 87 are more obvious, when compared with Cuibi 1, they have a higher susceptibility towards arsenic stress. With the extension of arsenic stress time, the tolerance of tobacco strengthens, and the susceptibility to arsenic stress weakens.