NaCl胁迫对黑麦根尖细胞染色体行为的影响

Effect of Salt Stress on Chromosomal Behavior of Root Tip Cells in Rye (Secale Cereale L. )

黑麦是一种耐盐、抗寒、抗旱性强的作物,其根系比小麦发达,是改良小麦抗性的重要外源基因供体。为了丰富小麦遗传变异,挖掘黑麦在小麦遗传改良中的利用潜力,本实验采用不同浓度的NaCl溶液,用两类不同方法对黑麦分别处理24 h和48 h(共四种处理),观察其根尖分生组织细胞的染色体行为。结果表明,经NaCl胁迫后的根尖细胞染色体行为产生异常(处理24 h,引起染色体畸变的盐浓度范田≥0.15 mol/L;处理48 h,盐浓度范围是≥0.10 mol/L),且随着NaCl溶液浓度的升高染色体异常行为不断增多,二者呈极显著正相关。其异常行为类型有微核、多核(2～3核)、小细胞核(细胞核高度浓缩)、染色体粘连、断裂、染色体桥、染色体落后、染色体多极分布和不均等分离。四种处理作以比较,发现萌发后根长0.5～1 cm再进行盐处理48 h,染色体受到的影响最大,染色体畸变率最高。

Rye is one kind of crop which have capacity of salt tolerance, cold resistance and drought resistance. The root of rye is stronger than the root of wheat. Rye is an important alien genetic donor for wheat resistance breeding. In order to obtain ideal new wheat varieties and exploit the potentials of rye, the abnormal chromosome behavior of root tip cells in rye was studied when rye was treated in 24 hours and 48 hours under different concentration of NaCl salt solution, respectively. The results showed that abnormal chromosome behavior emerged in rye root tip cells when treated by Salt. (In 24 hour, it was more than 0. 15 mol/L for critical concentration that lead to aberration of chromosomes; In 48 hours, it was more than 0. 1 mol/L). There existed significantly positive correlation between abnormal chromosome behavior and salt solution concentration. The types of abnormal chromosome behavior were micronucleus, multi-nucleus (two or three). Small nucleus (most concentrated nucleus), chromosome sticking, fragment, bridge, chromosome lagging, chromosome multidirectional distribution and unequal separation. Among four treatments, abnormal chromosome frequency was the highest when 0. 5-1 cm length rye root after germination was treated by salt in 48 hours.