Nikzad Azam, Kebede Berisso, Pinzon Jaime, Bhavikkumar Jani, Wang Xin, Yang Rong-Cai, Rahman Habibur
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
Northern Forestry Centre, Natural Resources Canada, Edmonton, AB, Canada.
Front Plant Sci. 2020 Jan 17;10:1691. doi: 10.3389/fpls.2019.01691. eCollection 2019.
The genetic base of canola need to be broadened for exploitation of heterosis at a greater level in the breeding of F hybrid canola cultivars. In this study, we evaluated 228 inbred canola lines derived from six × interspecific crosses and following two breeding methods (F- and BC-derived lines) to understand the effect of the alleles on heterosis for different agronomic and seed quality traits. Test hybrids of the inbreds derived from crosses involving vars. (cauliflower), (Chinese kale) and (cabbage) cv. Badger Shipper, on an average, gave about 10% mid-parent heterosis (MPH), and about 67% of the test hybrids gave higher seed yield than the common parent indicating that alleles can contribute to heterosis for seed yield in spring canola hybrids. This was also evident from a positive correlation of the genetic distance of the inbred lines from the common parent with MPH for seed yield ( = 0.31) as well as with hybrid yield ( = 0.26). Almost no correlation was found between genetic distance and MPH for seed oil and protein content as well as with the performance of the test hybrids for these two traits. The occurrence of positive correlation between seed yield of the inbred lines and test hybrids suggested the importance of the genes exerting additive effect for high seed yield in the hybrids. Very little or almost no heterosis was found for the other agronomic traits as well as for seed oil and protein content. While comparing the two breeding methods, no significant difference was found for seed yield of the test hybrids or the level of MPH; however, the BC-derived inbred and test hybrid populations flowered and matured earlier and had longer grain-filling period than the F-derived population. Thus, the results suggested that the gene pool can be used in the breeding of spring canola to improve seed yield in hybrid cultivars.
为了在杂交油菜品种的育种中更充分地利用杂种优势，需要拓宽油菜的遗传基础。在本研究中，我们评估了228个自交油菜品系，这些品系来自6个甘蓝型油菜×其他种间杂交组合，并采用了两种育种方法（F衍生系和BC衍生系），以了解甘蓝型油菜等位基因对不同农艺和种子品质性状杂种优势的影响。涉及甘蓝型油菜品种（花椰菜）、（芥蓝）和（甘蓝）cv. Badger Shipper杂交产生的自交系的测试杂种，平均产生约10%的中亲杂种优势（MPH），约67%的测试杂种种子产量高于普通甘蓝型油菜亲本，表明甘蓝型油菜等位基因可对春油菜杂种的种子产量杂种优势作出贡献。这也从自交系与普通甘蓝型油菜亲本的遗传距离与种子产量的MPH（r = 0.31）以及与杂种产量（r = 0.2）的正相关中得到证明。在遗传距离与种子油和蛋白质含量的MPH之间以及与这两个性状的测试杂种表现之间几乎没有发现相关性。自交系种子产量与测试杂种之间存在正相关，这表明在杂种中发挥加性效应的基因对高种子产量的重要性。对于其他农艺性状以及种子油和蛋白质含量，发现很少或几乎没有杂种优势。在比较两种育种方法时发现，测试杂种的种子产量或MPH水平没有显著差异；然而，BC衍生的自交系和测试杂种群体比F衍生群体开花和成熟更早，灌浆期更长。因此，结果表明甘蓝型油菜基因库可用于春油菜育种以提高杂交品种的种子产量。
