Kuang Yi, Lu Chi-Hsuan, Hsu Fu-Chiun
Department of Horticulture and Landscape Architecture, National Taiwan University, Taipei 10617, Taiwan.
Plants (Basel). 2021 Jan 22;10(2):209. doi: 10.3390/plants10020209.
Interspecific hybridization is an effective strategy in breeding programs for the introduction of new traits. Wild species within the genus are valuable genetic resources for providing new horticulture traits and to improve environmental adaptations. However, reproductive barriers associated with fertilization and hybrid sterility must be overcome to produce fertile hybrid progenies. To approach the breeding objectives for cut flower cultivars with long stem traits and adaptation to tropical/subtropical regions, a tropical species endemic to Taiwan, Kudo, was used as a parent to cross with other long stem species. Reciprocal crossing was effective in overcoming interspecific unilateral incompatibility in our crossed pairs. One superior hybrid, '103-1', produced capsules without seeds by selfing and backcrossing with pollens from either parent. Other than the seedless trait, failure of pollen releasing from anther, pollen aggregation and no pollen germination in '103-1' suggested its F sterility. Colchicine treatments on apical buds of '103-1' successfully overcame potential meiotic abnormalities by doubling ploidy. For the first time, fertile interspecific hybrids of and Engler were generated. The fertile hybrid has further produced progeny populations by crossing with or von Poelln, 'Ida'.
种间杂交是育种计划中引入新性状的有效策略。该属内的野生种是宝贵的遗传资源，可提供新的园艺性状并改善环境适应性。然而，必须克服与受精和杂种不育相关的生殖障碍才能产生可育的杂交后代。为了实现培育具有长茎性状且适应热带/亚热带地区的切花品种的育种目标，以台湾特有的热带物种Kudo作为亲本与其他长茎物种进行杂交。在我们的杂交组合中，正反交有效地克服了种间单向不亲和性。一个优良杂种‘103-1’，通过自交以及用双亲的花粉回交均产生了无籽的蒴果。除了无籽性状外，‘103-1’花药不释放花粉、花粉聚集且无花粉萌发表明其F不育。对‘103-1’顶芽进行秋水仙素处理通过使倍性加倍成功克服了潜在的减数分裂异常。首次获得了[具体物种1]和[具体物种2] Engler的可育种间杂种。该可育杂种通过与[具体物种3]或[具体物种4] von Poelln的‘Ida’杂交进一步产生了后代群体。
