摘要
运用荧光显微技术、整体透明法和石蜡切片法,对楸树自交及种内、种间杂交亲和性进行了显微观察。结果表明:无论自交或种内、种间杂交花粉均可在柱头萌发,但萌发时间和萌发率存在显著差异。花粉管在柱头分泌物中生长或穿透乳突细胞沿柱头中部维管束生长,之后进入花柱引导组织胞间隙。大量种内和种间杂交花粉管于授粉后12～24 h迅速生长至花柱基部;48～72 h进入子房;96～120 h前后发生双受精,肉眼可见子房发红膨大。自交授粉后约36%的花粉管在柱头和花柱上端终止生长;42%的花粉管于授粉后72～96 h进入子房;直到授粉后120 h花冠脱落为止,少数花粉管能够穿透胚囊,但未见双受精发生,子房无膨大。研究认为:楸树具有自交不亲和性,而种内和种间杂交是亲和的;其不亲和反应发生的最终位置在子房,时间在合子形成前,为合子前晚期自交不亲和类型。
By means of fluorescence microscopic technique, whole stain-clearing technique, and paraffin sectioning pro- cedure, the fertilization compatibility of Catalpa bungei after self, intraspecifie and interspeeifie cross-pollination were examined. It was founded that pollens could germinate whether self pollination or intraspeeific and interspeeific pollina- tion. But both the germination time and germination rate was significantly different. The pollen tubes either grew in the secretions of stigmas or penetrated the papilla cells, and then went along the inner vascular bundle, finally grew into the styles along the intercellular space of transmitting tissues. Most pollen tubes grew quickly to the basement of the style at 12 to 24 hours after intraspecifie and interspecific pollination, and entered the ovary after 1 or 2 days entered the ovary. Double fertilization was observed about 96 to120 hours after cross-pollination. At the same time we saw with naked eyes that the ovaries turned red and swelling. After self-pollination, 36% of pollen tubes ceased on the stigma or in the upper styles. 42% of pollen tubes could grow into the ovaries at 72 to 96 hours after self-pollination. Double fertilization could not be observed although part of pollen tubes penetrated the ovules. Pistils fell off at 120 hours after self-pollination with- out presenting any swelling of the ovary. It was clear that C. bungei exhibited self-incompatibility, intraspecific cross- compatibility, and interspecific cross-compatibility. Because the site of pollen tube termination was in the ovary, and the time was pre-zygotic, C. bungei was considered to be a pre-zygotic late-acting seff-incompatibility type.
出处
《南京林业大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第4期1-7,共7页
Journal of Nanjing Forestry University：Natural Sciences Edition
基金
"十二五"国家科技支撑计划(2012BAD21B03)
江苏省农业科技支撑项目(BE2010311)
关键词
楸树
花粉萌发
花粉管生长
晚期自交不亲和
Catalpa bungei
pollen germination
pollen tube growth
late-acting self-incompatibility
