小麦种子萌发对盐胁迫的生物学响应

Response of wheat seed germination to salt stress

为了比较不同小麦品种(系)间萌发期的耐盐性差异,筛选出适合盐渍化土壤种植的小麦品种,采用NaCl水溶液模拟盐胁迫的方法,以蒸馏水为对照(CK),设置50、100、150和200 mmol/L 4个盐浓度梯度,对偃展4110、百农201、周麦18、周麦22、百农207、华育198、百农307(系)和百农AK58进行盐胁迫处理,研究小麦种子萌发对盐胁迫的生物学响应.结果表明:(1)随着NaCl浓度的增加,8个小麦品种(系)的种子发芽率及幼苗株高、根长、苗鲜质量、根鲜质量大体呈下降趋势,根数呈先上升后下降趋势.(2)在50 mmol/L NaCl处理下,百农207、百农307和百农201种子发芽率分别较对照提高了5.42%(P<0.05)、4.99%(P<0.05)和0.10%,浓度为150~200 mmol/L时各小麦品种(系)发芽率严重受到抑制.(3)50~150 mmol/L NaCl处理时,不同小麦品种(系)根长受抑制作用大于幼苗株高,200 mmol/L时则相反,对周麦22和百农201株高和根长的抑制率较小;小麦根数在低中盐浓度(≤100 mmol/L)下增加,高盐浓度(≥150 mmol/L)下减少,以百农201、周麦22和偃展4110根数较多;NaCl胁迫使所有小麦品种(系)的苗鲜质量和根鲜质量均下降,以百农201、周麦22和百农307苗鲜质量和根鲜质量较高.按照耐盐性将8个供试小麦品种(系)聚类为4类:第一类包括百农201和周麦22(强耐盐小麦组);第二类包括偃展4110和百农307(较强耐盐小麦组);第三类包括百农207(一般耐盐小麦组);第四类包括周麦18、华育198和百农AK58(耐盐能力较差).

In order to identify differences of salt tolerance among different wheat varieties （lines） in emergence stage,some varieties （lines） were selected for the experiment.By simulated salt stress with NaC1 aqueous solution,the distilled water was used as the control （CK）.The experiment was conducted with eight wheat cuhivars including Yanzhan 4110,Bainong 201,Zhoumai 18,Zhoumai 22,Bainong 207,Huayu 198,Bainong 307（line） and Bainong AK58. The seeds of each cultivar were water cultivated in five salt concentrations of CK,50,100,150 and 200 mmol/L.The seedlings of each treatment were sampled after cultivated for 7 and 18 d respectively,for studying response of wheat seed germination to salt stress.The results showed as follows： （1）The germinating rate,seedling height,root length, seedling fresh weight and root fresh weight decreased with the increasing of NaC1 concentration,but root number first increased then decreased. （2）The seed germinating rate of Bainong 207,Bainong 307 （line） and Bainong 201 increased by 4.99%（P〈0.05）,5.00% （P〈0.05） and 0.10% than the control respectively under the 50 mmol/L NaC1 treatment,the seed germinating rate of eight wheat varieties（lines） was seriously inhibited under the 150-200 mmol/L NaC1 treatment. （3）Under the 50-150 mmol/L NaCI treatment,the root length was inhibited more than the seedling height,while the 200 mmol/L NaC1 treatment showed the opposite results,the inhibition rates of seedling height and root length against Zhoumai 22 and Bainong 201 were lower,the root numbers increased under the low or moderate salt stress（lower than or equal to 100 mmol/L）,but decreased under high salt concentration（higher than or equal to 150 mmol/L）,cultivar with Bainong 207,Zhoumai 22 and Yanzhan 4110 had much more root number.The fresh weight of seedling and root of the eight cuhivars declined under the salt stress,the fresh weight of the seedling and root of Bainong 201,Zhoumai 22 and Bainong 307 （line） were higher.Eight kinds of wheat were divided into four categories by clustering analysis.The first category was strong salt-tolerant group which included Bainong 201 and Zhoumai 22.The second category was stronger sah-tolerant group which included Yanzhan 4110 and Bainong 307 （line）.The third category was generally salt-tolerant group which included Bainong 207.The fourth category included Zhoumai 18,Huayu 198 and Bainong AK58,and the ability of resistant to salt of these three varieties（lines） was poor.