五倍体和同源十倍体‘怀白菊’农艺性状及耐寒性的差异分析

Differential agronomic traits and cold tolerances in Chrysanthemum morifolium ‘Huaibai' between pentaploid and its corresponding autodecaploid

以前期获得的‘怀白菊’(Chrysanthemum morifolium‘Huaibai’)四个十倍体株系HB-D1、HB-D2、HB-D3、HB-D4和其对照株系HB-CK(五倍体)为试材,进行大田种植,观测其农艺性状,筛选出大田表现最优的十倍体株系;然后将筛选出的最优十倍体株系和对照株系的试管苗置于人工控制的低温胁迫(昼10°C/夜5°C)条件下7 d,比较分析二者的耐寒性。结果表明:在大田生长过程中,与五倍体对照株系HB-CK相比,同源十倍体株系中HB-D1、HB-D2、HB-D3长势更旺、冠幅增大、分蘖数增加、产量提高,以HB-D2表现最佳,而HB-D4表现不及对照;在人工控制的低温胁迫条件下,同源十倍体株系HB-D2叶片中叶绿素、可溶性蛋白及脯氨酸含量降幅及超氧化物歧化酶、过氧化物酶和过氧化氢酶活性的降幅均小于五倍体对照株系,且相对电导率、丙二醛含量的增幅也小于五倍体对照株系,说明染色体加倍后的‘怀白菊’在大田的表现并不一定都优于同源五倍体对照株系,同源十倍体株系HB-D2的耐寒性强于其五倍体对照株系。

Autodecaploid strains of Chrysanthemum morifolium ＇Huaibai＇, including HB-D1, HB-D2, HB-D3 and HB-D4, and their corresponding pentaploid, HB-CK, were used in this study. To identify autodecaploid strain with optimal field performance, these strains were transplanted into field and their agronomic traits were investigated. Then their tolerance to cold stress were compared at 10~C/5~C （night/day） for 7 days in an artifi- cially controlled chamber. The results show that the HB-D1, HB-D2 and HB-D3 showed better field growth than HB-CK in terms of growth vigor, crown breadth, tiller number and yield, in which HB-D2 was the best in all strains, but the agronomic traits of HB-D4 showed no better than control. Under the artificially controlled cold stress, in leaves of HB-D2, the decreasing of total chlorophyll, soluble protein, proline contents, the activi- ties of SOD, POD and CAT, the increasing of relative conductivity and MDA content was not as significant as the HB-CK control. It shows that chromosome doubling in ＇Huaibai＇ chrysanthemum did not result in better field performance in all traits, and the autodecaploid strain HB-D2 had a higher cold tolerance than its penta- ploid control.