Induction of Ethephon on Aerenchyma Formation in Rice Roots

Abstract

Abstract: The effects of ethephon on the constitutive aerenchyma formation in the roots were studied with Yangdao 6 as material. The results showed that the number of air spaces formed by disintegrated cells in mediopellis increased significantly with the rising ethephon concentrations, while superoxide dismutase enzyme activity showed downward trends. Compared with the control, the expression levels of xyloglucan endotransglycosylase(XET) gene were markedly higher both at apical 10 mm and distal part of roots in the 100 mg/L ethephon treated plants. The accumulation of XET gene was supposed to be associated with the aerenchyma development. Furthermore, earlier cortical cell death was observed under ethephon treatment，most of nucleus of cells at 4 mm from the root apex disintegrated with many Golgi apparatus, mitochondria and membranebound vesicles around the cell wall.

Key words: rice, root, ethephon, constitutive aerenchyma, xyloglucan endotransglycosylase gene

摘要： 以扬稻6号（Oryza sativa L.）幼苗为材料，研究乙烯利对根内组成型通气组织形成的影响。结果表明，随营养液中乙烯利浓度的增高，中皮层部位细胞解体形成通气空腔数增多，超氧化物歧化酶的活性呈下降趋势；以正常生长的水稻根系为对照，100 mg/L乙烯利处理后根尖10 mm和距根尖10 mm以上部位的木葡聚糖转葡糖苷酶（XET）基因表达量均显著高于对照相应部位，XET基因的积累与通气组织形成具有一致性；对处理与对照根尖10 mm部位超微结构比较发现，乙烯利处理后根系皮层细胞发生死亡解体的时间早，在距离根尖4 mm处多数细胞内核已解体消亡，细胞壁周围可见较多的高尔基体、线粒体和膜包裹的空泡等。

关键词: 水稻, 根, 乙烯利, 组成型通气组织, 木葡聚糖转葡糖苷酶基因

KONG Yu ,WANG Zhong ,GU Yunjie ,XIONG Fei ,CHEN Gang ,HAN Ying. Induction of Ethephon on Aerenchyma Formation in Rice Roots[J]. Chinese Journal of Rice Science.

孔妤王忠, 顾蕴洁,熊飞, 陈刚,韩鹰. 乙烯利诱导水稻根内通气组织形成的研究
[J]. 中国水稻科学.

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