白菜型冬油菜抗寒相关性状的遗传分析

【目的】了解白菜型冬油菜抗寒相关性状的遗传方式,为油菜抗寒性的遗传育种提供一定的理论依据。【方法】以6个抗寒性不同的白菜型冬油菜品种(系)为亲本材料,按照GriffingⅠ配制完全双列杂交组合,将亲本和F_1种植后测定抗寒性相关的性状以获得试验数据。采用QGAStation软件中的加性-显性遗传模型和MINQUE(1)法,对白菜型冬油菜越冬率及11个理化性状的遗传方差分量比率、遗传相关性、亲本加性效应、组合显性效应和遗传率以及杂种优势进行分析。【结果】越冬率、POD活性、SOD活性、可溶性糖含量、相对电导率、叶绿素含量、蒸腾速率和气孔导度的遗传主要以加性效应为主,显性效应影响较小;CAT活性、丙二醛含量、可溶性蛋白含量和净光合速率则主要以显性效应为主。在基因型和表现型的相关分析上,越冬率与CAT活性、POD活性、SOD活性、可溶性蛋白含量、可溶性糖含量、叶绿素含量、蒸腾速率、气孔导度和净光合速率呈极显著正相关,与丙二醛含量和相对电导率则呈极显著负相关。陇油7号和陇油8号在越冬率、CAT活性、POD活性、SOD活性、可溶性蛋白含量、可溶性糖含量、叶绿素含量、蒸腾速率、气孔导度和净光合速率上的加性效应均呈正值,表明陇油7号和陇油8号可用作提高后代抗寒性的亲本。显性效应分析表明,陇油7号×GY和陇油7号×陇油8号是抗寒性强的组合。狭义遗传率以SOD活性、相对电导率、蒸腾速率和越冬率的表现最好,分别为74.63%、59.06%、57.49%和56.87%,CAT活性最低,为2.83%。CAT活性、可溶性蛋白含量和净光合速率3个抗寒相关性状具有很强的群体平均优势和群体超亲优势。【结论】越冬率、SOD活性、相对电导率和蒸腾速率适宜在早代选择,亲本评价分析指出,陇油7号的一般配合力高,可作为冬油菜抗寒性改良的首选亲本。

Genetic Analysis of Traits Related to Cold Resistance in Winter Rapeseed (Brassica rapa L.)

【Objective】The objective of this paper is to understand genetic way and to provide a theoretical foundation of cold resistance traits in winter rapeseed (Brassica rapa L.). 【Method】 In this study, six winter rapeseed cultivars with different cold resistances were used as parent materials to make complete diallel cross combinations with the Griffing methodⅠ. The parents and F1 generations were planted to obtain the data of cold resistance traits. By using the additive-dominant model and MINQUE(1) method, the genetic variance, genetic correlation, parent additive effects, combination dominant effects and heritability, and heterosis of over wintering rate and 11 traits in winter rapeseed were analyzed.【Result】Over wintering rate, POD activity, SOD activity, SS content, relative electrolytic leakage, chlorophyll content, transpiration rate and stomatal conductance were mainly controlled by additive effects, and dominant effects were much less important. The dominant effects prevailed in the traits of CAT activity, MDA content, SP content and net photosynthetic rate. Over wintering rate was detected to be significantly and positively correlated with CAT activity, POD activity, SOD activity, SP content, SS content, chlorophyll content, transpiration rate, stomatal conductance and net photosynthetic rate, but negatively correlated with MDA content and relative electrolytic leakage. Longyou 7 and Longyou 8 had positively additive effects in the traits of overwintering rate, CAT activity, POD activity, SOD activity, SP content, SS content, chlorophyll content, transpiration rate, stomatal conductance and net photosynthetic rate, which indicated Longyou 7 and Longyou 8 could be used as parents that improved cold resistance of generations. The results of dominant effects analysis showed that Longyou 7×GY and Longyou 7×Longyou 8 had stronger cold resistance. As for the narrow heritabilities, SOD activity, relative electrolytic leakage, transpiration rate and overwintering rate were 74.63%, 59.06%, 57.49% and 56.87%, respectively, and CAT activity was the lowest (2.83%). CAT activity, SP content and net photosynthetic rate had stronger population mean heterosis and population over-parent heterosis. 【Conclusion】Overwintering rate, SOD activity, relative electrolytic leakage and transpiration rate were used in selection at early generation. Among the 6 elite breeding lines, Longyou 7 was recommended for using as direct parental line due to its higher general combining ability in cold resistance traits.