Plant Breeding and Acclimatization Institute-National Research Institute, Department of Genetics and Breeding of Oilseed Crops, Poznań, Poland.
Institute of Plant Genetics, Polish Academy of Sciences, Department of Biometry and Bioinformatics, Poznań, Poland.
PLoS One. 2019 Apr 18;14(4):e0215661. doi: 10.1371/journal.pone.0215661. eCollection 2019.
Resynthesized (RS) Brassica napus can be used to increase the genetic diversity of this important crop plant and to develop the heterotic gene pool required for successful hybrid breeding programmes. The level of heterosis in F1 hybrids depends on the individual performance of the parents and on the degree of genetic difference between them. However, RS forms obtained from crosses of B. rapa ssp. with B. oleracea ssp. possess many undesirable agronomic traits, such as low quality of seeds, low yield and seed oil content, high erucic acid level in the oil and high glucosinolate content in seed meal. Therefore, RS oilseed rape needs to be improved by crossing with natural double-low oilseed rape, leading to selected double-low quality semi-RS lines that can be used for breeding. In this study, we evaluated the seed yield potential of F1 hybrids derived from crosses between Ogura cytoplasmic male-sterility (CMS) lines and doubled haploid (DH) semi-RS lines with restorer gene in three locations in Poland. The genotype by environment interaction (GE interaction) and general combining ability (GCA) of the restorer and CMS line effects, as well as the effects of heterosis, were also assessed. The results of the study provide the first insights into the use of semi-RS lines as components for the development of new hybrid cultivars. Even the introduction of 50% of the RS oilseed rape genotype to natural restorer lines resulted in a marked heterosis effect, with seed yield ranging from 4.56% to 90.17% more than that of the better parent. The yield of the best hybrid amounted to 108.6% of the seed yield of the open-pollinated cultivar Monolit and 94.4% of that of the hybrid cultivar Arsenal. The best DH semi-RS line S1, which had a significantly positive GCA for seed yield, can be recommended as a possible parent for inclusion in breeding programmes aimed at developing new hybrid cultivars.
再合成（RS）油菜可以用于增加这种重要作物的遗传多样性，并开发用于成功杂交育种计划所需的杂种优势基因库。F1 杂种的杂种优势水平取决于亲本的个体表现和它们之间的遗传差异程度。然而，从甘蓝型油菜亚种与芸薹亚种杂交获得的 RS 形式具有许多不良的农艺性状，如种子质量低、产量和种子油含量低、油中芥酸水平高以及种子粉中硫代葡萄糖苷含量高。因此，RS 油菜需要通过与天然双低油菜杂交进行改良，从而产生具有所选双低质量的半 RS 系，可用于育种。在这项研究中，我们在波兰的三个地点评估了来自 Ogura 细胞质雄性不育（CMS）系和具有恢复基因的加倍单倍体（DH）半 RS 系杂交产生的 F1 杂种的种子产量潜力。还评估了恢复系和 CMS 系效应的基因型与环境互作（GE 互作）和一般配合力（GCA）以及杂种优势的效应。该研究的结果首次提供了有关将半 RS 系用作开发新杂交品种的组成部分的见解。即使将 50%的 RS 油菜基因型引入到天然恢复系中，也会产生明显的杂种优势效应，种子产量比较好的亲本高 4.56%至 90.17%。最佳杂种的产量达到了自交品种 Monolit 种子产量的 108.6%和杂交品种 Arsenal 的 94.4%。具有显著正种子产量 GCA 的最佳 DH 半 RS 系 S1 可推荐作为可能的亲本，用于旨在开发新杂交品种的育种计划。
