秋水仙素对大蒜茎尖试管苗四倍体的诱导  

The Tetraploid Induction of Shoot-Tip Plantlets with Colchicine in Garlic

作　　者：孔素萍[1,2] 曹齐卫[2] 孙敬强[2] 刘波[2] 徐坤[1] 

机构地区：[1]山东农业大学园艺科学与工程学院/农业部黄淮地区园艺作物生物学与种质创制重点实验室,山东泰安271018 [2]山东省农业科学院蔬菜花卉研究所/山东省设施蔬菜生物学重点实验室,济南250100

出　　处：《中国农业科学》2014年第15期3025-3033,共9页Scientia Agricultura Sinica

基　　金：国家公益性行业(农业)科研专项(200903018);山东省农业良种工程(2011LZ06-01)

摘　　要：【目的】大蒜为无性繁殖作物,难以采用常规育种方法选育新品种,而化学诱变作为种质创制的重要方法之一,在一些作物上获得了较好的效果。探讨秋水仙素对大蒜茎尖组培试管苗多倍体的诱变效应,旨在为创新大蒜种质提供理论依据和技术方法。【方法】选用山东‘苍山蒲棵’、四川‘正月早’和‘新疆紫皮’3个生态区域的大蒜品种,鳞茎经自然晾干通过休眠后,取鳞芽茎尖为外植体接种到不同处理的培养基上,采用二次饱和-D最优设计方法,研究秋水仙素不同浓度及处理时间对大蒜茎尖试管苗成苗率及染色体加倍率的影响,并建立相关回归模型;通过对回归模型进行解析,确定诱变大蒜四倍体的优化方案;采用流式细胞仪检测幼叶和根尖压片染色体计数相结合的方法进行染色体倍性鉴定。【结果】利用流式细胞仪检测的四倍体大蒜植株叶片DNA相对含量是二倍体对照大蒜‘苍山蒲棵’的2倍;通过染色体计数法鉴定二倍体植株根尖染色体为2n=2x=16,而四倍体植株染色体为2n=4x=32。在秋水仙素处理大蒜茎尖诱变四倍体过程中,随秋水仙素处理浓度的升高及时间的延长,3个大蒜品种试管苗成苗率均逐渐降低,且处理浓度的影响大于处理时间;品种间成苗率存在显著差异,以‘正月早’较高,‘新疆紫皮’次之,‘苍山蒲棵’较低,其处理间平均成苗率分别为48.69%、46.73%和41.83%。秋水仙素对大蒜四倍体的诱变效应以处理浓度大于处理时间,不同大蒜品种对秋水仙素的反应存在显著差异,虽然‘苍山蒲棵’、‘正月早’与‘新疆紫皮’的最高四倍体诱导率分别达15.69%、15.69%和23.53%,但大蒜四倍体平均诱导率则以‘正月早’最高,‘苍山蒲棵’次之,‘新疆紫皮’最低,分别为9.15%、7.84%和6.53%。经计算机模拟寻优,求得的3个大蒜品种试管苗成苗率均超过50%的处理方案为秋水�[Objective]Garlic is a vegetative crop. It is difficult to use conventional method to breed new varieties. Chemical mutagenesis plays an important role in germplasm innovation, and the effect is admirable in some crops. This paper mainly discussed the mutagenic effect of colchicine on in vitro shoot-tips of garlic with the aim at finding a theoretical and methodical basis for obtaining new garlic germplasm. [Method] Garlic cultivars of Cangshan Puke, Zhengyuezao, and Xinjiang purple were collected from different regions. After dormancy broken, the selected shoot-tips from bulbs of garlic were cultured in different media and proceeded to plant regeneration. The rate of plantlet regeneration and tetraploid in vitro shoot-tips were studied in three garlic varieties induced by colchicine exposure. Correlative model of different colchicine concentrations and time duration was established by applying D-optimal design, so as to determine the optimum scheme of the tetraploid induction of garlic. The plant ploidy was identified by Flow Cytometry Analysis and chromosome counts of the root-tips.[Result]The result showed that the DNA content of tetraploid garlic leaf was twice that of diploid garlic Cangshan Puke by flow cytometry analysis. The diploid chromosome number was 2n=2x=16 and the tetraploid chromosome number was 2n=4x=32 by chromosome counting. In colchicine treatment process, the rate of plantlet regeneration was significantly decreased when treated with colchicine at higher concentration and after longer duration. And the concentration of colchicine had a stronger effect on plantlet regeneration than time duration. The difference among the three garlic varieties was significant. As an outstanding example, the plantlet of Cangshan Puke survived significantly fewer than Zhengyuezao and Xinjiang purple. And the plantlet rates were 41.83%, 48.69% and 46.73%, respectively. The concentration of colchicine had a more significant effect on tetraploid induction than the treatment duration. The difference of tetraploid ra

关 键 词：大蒜 试管苗 秋水仙素 四倍体 

分 类 号：S633.4[农业科学—蔬菜学]