水稻spl5突变体类病变受光诱导的机理分析

Occurrence mechanism of lesion mimic induced by light in rice spl5 mutant

为了研究光诱导植物类病变发生的机理,以水稻spl5突变体及野生型对照为材料,进行遮光和滤光处理,观察其类病变的发生情况.透射电镜观察叶绿体亚显微结构,分光光度法测定叶绿素含量,DAB染色法分析光照和遮光条件下叶片中H2O2的积累情况.结果表明:2种光合作用的主要光源(蓝光与红光)及紫外光能诱发spl5突变体产生类病变;在spl5突变体未出现类病斑的叶片中,其叶绿体发育异常、叶绿素含量显著降低; spl5突变体叶片经光照后大量积累H2O2,遮光后则无H2O2积累.推测spl5突变体在光照下叶绿体不能进行正常的光能转化,产生大量的活性氧,从而引发细胞坏死.

In order to study the mechanism of light-induced plant pathological,the spl5 mutants of rice and wild-type controls were used as materials,through shading and filtering treatment,the occurrence of their lesions was observed;The submicroscopic structure of chloroplasts was also observed by TEM and the chlorophyll content was measured by spectrophotometry,and the accumulation of H 2O 2 in leaves under light and shading conditions was analyzed by DAB staining.The results showed that the two main photosynthetic light sources(blue and red light)and ultraviolet light could induce spl5 mutants.The chloroplast development was abnormal and chlorophyll contents were significantly decreased in the leaves of spl5 mutants without disease-like lesions;The spl5 mutant leaves accumulated H 2O 2 after light irradiation,and there was no H 2O 2 accumulation after shading.It was inferred that the chloroplasts of spl5 mutant could not undergo normal light energy transformation under light and would produce a large amount of reactive oxygen species,thus cause cell necrosis.