盐胁迫对小麦代换系幼苗叶片保护酶活性影响及染色体效应

Effects of Salt Stress on Protective Enzyme Activities and Chromosome of Wheat Substitution Lines

为研究盐胁迫对小麦代换系酶活性的影响,以中国春-Synthetic 6x染色体代换系及其亲本为材料,通过测定在盐处理条件下幼苗抗氧化酶SOD、POD活性和丙二醛(MDA)含量变化,并对其相关耐盐特性的基因进行染色体定位。采用霍格兰营养液水培法,设置对照(0 mmol/L NaCl)和盐处理(150 mmol/L NaCl),在幼苗两叶一心时进行处理,四叶一心时取样,分别测定对照和盐处理条件下幼苗的SOD和POD活性以及MDA含量。在盐胁迫条件下,小麦代换系幼苗SOD和POD活性显著升高,丙二醛含量降低。其中,1A、5A、6A、1B、5B、6B、7B和5D代换系的SOD活性显著或极显著高于母本中国春,2A、1B、2B、3B、5B、6B、5D和6D代换系的相对SOD活性显著或极显著高于母本中国春;3A、4A、5A、6A、7A、6B和7D代换系的POD活性显著或极显著高于中国春,4A、5A、6B、1D和7D代换系的相对POD活性显著或极显著高于中国春。由于保护酶的作用,在盐胁迫条件下,多数代换系MDA含量明显减少,2A、3A、4A、6A、1B、3B、4B、5B、6B、7B、1D、5D和7D代换系的MDA含量显著或极显著低于母本中国春,2A、6A、6B、1D和2D代换系的相对MDA含量显著或极显著低于母本中国春。Synthetic 6x的1B、5B、6B和5D染色体上可能存在诱导幼苗SOD活性增强的基因,4A、5A、6B和7D染色体上可能存在诱导幼苗POD活性增强的基因,抑制幼苗MDA含量增高的基因可能存在于2A、6A、6B和1D染色体上。

Wheat substitution lines between Chinese Spring and Synthetic 6x under the treatments of salt stress were studied to research the effect on antioxidant enzymes SOD,POD activities and MDA content and locating the gene controlling antioxidant enzymes SOD,POD activities and MDA content. Two control groups were carried out under hydroponic experiment. The first control group was growing under Hoagland＇s solution（ 0 mmol /L NaCl）. The second control group was growing under Hoagland＇s solution with 150 mmol /L NaCl. Seedlings was treated at the two-leaf stage and measured SOD and POD activity and MDA content under control and salt treatment conditions at four-leaf stage. Substitution lines of wheat significantly increased of SOD and POD activity under salt stress conditions,but the MDA content decreased. SOD activity of 1A,5A,6A,1B,5B,6B,7B and 5D substitution lines were significantly or very significantly higher than female Chinese Spring. 2A,1B,2B,3B,5B,6B,5D and 6D substitution lines of relative SOD activity was significantly or very significantly higher than female Chinese Spring; POD activity of 3A,4A,5A,6A,7A,6B and 7D substitution lines were significantly or very significantly higher than China Spring,4A,5A,6B,1D and 7D substitution lines of relative POD activity significantly or very significantly higherthan Chinese Spring. As the role of protective enzymes under salt stress conditions,the MDA content of substitution lines was significantly reduced. 2A,3A,4A,6A,1B,3B,4B,5B,6B,7B,1D,5D and 7D substitution lines of MDA content were significantly or very significantly lower than female Chinese Spring,2A,6A,6B,1D and 2D substitution lines of relative MDA content significantly or very significantly lower than female Chinese Spring. The results showed that the genes increased SOD activity and POD activity might be located on 1B,5B,6B and 5D chromosome and4 A,5A,6B and 7D chromosome of Synthetic 6x respectively; while the genes inhibiting content might be exist in2 A,6A,6B and 1D chromosome of Synthetic 6x under salt stress.