Abstract: DNA methylation inhibitors can affect plant flowering, growth and stress responses by altering the genome DNA methylation level. In this study, salt-tolerant and salt-sensitive rice cultivars were treated with DNA methylation inhibitor at germination and seedling stages, respectively. And salt stress was applied to the treated seedlings. The results showed that the DNA methylation inhibitors treatment at germination stage resulted in a significant decrease in germination rate, and the seedlings, which showed short stature, clusters, death and other traits, and plant height, root length and dry weight were also significantly inhibited. Meanwhile, DNA methylation inhibitor could reduce the sodium ion concentration in the shoots under salt stress and increase the activity of ascorbate peroxidase (APX). Above results showed DNA methylation inhibitor affected rice growth and development and the salt tolerance in rice by changing the methylation level of genomic DNA to affect potassium and sodium ion concentrations and antioxidant enzyme activities.

Key words: DNA methylation inhibitors, rice, growth and development, salt tolerance

摘要： DNA甲基化抑制剂能够通过改变植物基因组的DNA甲基化水平从而对植物的开花、生长发育和抗逆性产生影响。以耐盐和盐敏感水稻品种为材料，分别在水稻萌发期和幼苗期用DNA甲基化抑制剂进行处理，并对处理后的幼苗进行盐胁迫。结果表明：萌发期抑制剂处理导致种子萌发率显著降低，幼苗出现矮化、成簇、死亡等症状，株高、根长和干重也受到了显著的抑制；同时，DNA甲基化抑制剂处理可以降低盐胁迫时地上部的钠离子浓度、提高抗坏血酸过氧化物酶（APX）的活性。上述结果表明DNA甲基化抑制剂通过改变基因组DNA的甲基化水平来影响水稻的生长发育，并通过影响离子吸收和抗氧化酶类的活性来影响水稻的耐盐性。

关键词: DNA甲基化抑制剂, 水稻, 生长发育, 耐盐性