景宁木兰(Magnolia sinostellata)远缘杂交授粉过程障碍研究  

Distant Hybridization Barriers of Magnolia sinostellata in the Pollination Process

作　　者：陈翔翔[1] 卢璐[1] 范李节 王倩颖[1] 尹增芳 申亚梅[1] 

机构地区：[1]浙江农林大学风景园林与建筑学院,临安311300 [2]南京林业大学生物与环境学院,南京210037

出　　处：《植物研究》2017年第6期816-824,共9页Bulletin of Botanical Research

基　　金：国家自然科学基金资助项目(31400599);浙江省农业新品种选育重大科技专项(2012C12909-4)~~

摘　　要：以景宁木兰(Magnolia sinostellata)为亲本,分别与望春玉兰(M.biondii)、紫玉兰(M.liliiflora)、红运二乔(M.soulangeana‘Red lucky’)、丹馨玉兰(M.soulangeana‘Danxin’)进行种间远缘杂交,并以景宁木兰自交为对照,研究了景宁木兰自交和杂交亲和性。结果表明:(1)景宁木兰具有较高的花粉活力与柱头可授性,花粉管能正常进入杂交母本花柱,自交结实率为2%;(2)以景宁木兰为父本,紫玉兰柱头对其花粉具有较好的识别性,花粉萌发率和花粉管生长速度均高于以红运二乔和丹馨玉兰做母本的组合,花粉管生长较为正常,结实率为25%,而与红运玉兰杂交的结实率为4%,与丹馨玉兰杂交的结实率为0%;(3)以景宁木兰为母本,望春玉兰花粉在其柱头上的萌发比率高于其他4个组合,但花粉管生长过程中出现扭曲,景宁木兰花柱内出现胼胝质沉积,且最终并未获得种子。花粉管发育镜检结果表明:受精前障碍即花粉管进入花柱基部前生长异常是引起景宁木兰与丹馨玉兰、望春玉兰杂交不结实的主要原因;并进一步推测花粉管进入子房后的异常状态是导致景宁木兰自交,与红运二乔杂交结实率低的主要原因。With selfing of Magnolia sinostellata as a control, distant crosses of M. sinosteUata with M. biondii,M. liliiflora, M. soulangeana ＇ Red lucky＇ and M. soulangeana ＇ Danxin＇ , respectively, were conducted to study the compatibility of selfing and that between species. M. sinostellata had a relatively high pollen viability and stigma receptivity, and its pollen tube could go into the maternal style normally but had a selfing-based fruiting rate of 2%. The pollen from M. sinostellata was fast identified by the stigma of M. liliiflora and germinated at a higher percentage with a faster growing normal tube than by those of M. soulangeana ＇ Red lucky＇ and M. soulangeana ＇ Danxin＇. M. liliiflora × M. sinostellata had a fruiting rate of 25% while the fruiting rate of M. soulangeana ＇ Red lucky＇ × M. sinostellata and M. ＇ Fragrant cloud＇ × M. sinostellata was only 4% and 0, respectively. With M. sinostellata as a maternal parent, the pollen of M. biondii had a higher pollen germination rate than that of other three species, but the pollen tube twisted during growth and the callose was formed inside the style of M. sinostellata, which resulted in no seed formation. All these indicated that pre- fertilization barriers, i.e. abnormal growth of pollen tube before reaching the bottom of the style, was the main reason for no fruiting in the cross of M. sinostellata with either of M. soulangeana ＇ Danxin＇ and M. biondii. The abnormal state of pollen tube after entering into the ovary might lead to a low fruiting rate from selfing of M. sinostellata and hybridization of M. sinostellata with M. liliiflora, or M. soulangeana ＇ Red lucky＇.

关 键 词：景宁木兰 人工杂交 花粉萌发 结实率 杂交亲和性 

分 类 号：S685.11[农业科学—观赏园艺]