【作者】 刘冬云；

【导师】 刘燕；

【作者基本信息】 北京林业大学 ， 园林植物与观赏园艺， 2011， 博士

【摘要】 山丹(Lilium pumilum DC.)别名细叶百合,为百合科百合属多年生草本,其花色鲜艳、姿形秀丽,适应性强,具有许多优良性状,是百合育种和品质改良的重要基因资源。我国拥有丰富的野生山丹种质资源,开展其野生种质资源的调查收集,研究其居群在不同地理位置、生境、气候条件等生态因子下的遗传变异,了解山丹的抗逆特性,对于野生山丹种质资源的保护和百合育种具有重要意义。本研究以中国山丹野生种质为材料,在居群水平上从形态学、孢粉学、染色体核型、分子标记、抗逆性等方面进行了较为系统的研究,并初步探讨了山丹在百合杂交育种中的利用,对于野生山丹种质资源的保护和百合育种具有重要意义。主要结果如下：1.通过引种种植观测,25个山丹居群的物候期及形态性状表现出居群间的差异大于居群内的差异。差异主要来源于花蕾毛的有无、叶宽、株高、花色等性状。叶长、花药长、花朵直径、果实纵径等性状与地理因子(经度、纬度、海拔)存在显著或极显著相关性。物候期、株高、花型、花色的多样性在育种中均有较高的利用价值。扫描电镜观察山丹花粉粒形态为单花粉粒,极面观椭圆体,具单萌发沟,且居群间花粉性状的变异大于居群内的变异。2.核型分析表明,25个居群间染色体核型存在一定的多样性。各居群山丹均为二倍体种,染色体基数为x=12,根尖细胞中的染色体数目大多数为2n=2x=24,但根尖细胞中的染色体数目并不完一致,除2n=2x=24外,还存在着附加1-3条额外染色体的非整倍体细胞。山丹染色体类型有st, sm, t, m, T。最长与最短染色体的比值在1.73～5.90之间,多数在2-4之间；不对称系数介于75.6%-89.6%之间；核型类型有3B、4B、3A、4A、3C、4C,其中以3B类型最多,占56%。表明不同山丹居群在染色体水平上表现出一定的多样性。3.SSR分析表明,12对EST-SSR引物在25个居群种内多念位点百分率达93.5%。不同居群内的多态性带数比例变幅在78.55%～91.92%之间,平均值为82.36%,表明野生山丹居群在分子水平上表现出丰富的遗传多样性。这与对山丹形态、花粉、核型多样性的分析结果一致。综合各居群的观测等位基因数(A)、有效等位基因数(Ae)、香浓信息指数(I)、观测杂合度(Ho)、预期杂合度(He)得出的结论为,25个山丹居群中白石山居群遗传多样性最高,邢台的最低。4.抗逆研究表明：不同山丹居群抗尖孢镰刀菌的能力不同,25个山丹居群抗尖孢镰刀菌的能力以唐山、甘肃居群抗性最强,以宁夏、辽宁居群最弱。山丹能够忍耐.30。C的低温；山丹在37℃高温下生长良好,并能够忍耐短时间(<72h)的40。C高温。山丹在含盐量≤0.3%的土壤中能够正常生长,在高于0.3%的土壤中则会受到伤害。山丹适合在30%-60%的遮荫度下生长。5.山丹花粉适宜的萌发培养基为5%蔗糖+10%硼酸,.20。C下贮减120天时山丹花粉仍有50.5%萌发率。杂交授粉研究表明,山丹ב西伯利亚’有较高的亲和性。延迟授粉、切割花柱、施用萘乙酸(NAA)等方法对山丹与‘西伯利亚’、‘白天堂’、‘精粹’等的杂交座果率有一定提高。综合分析认为,山丹在中国北方各省分布广泛,具有从形态、花粉、核型到DNA分子水平的多层和丰富的遗传变异,是我国百合育种得天独厚的宝贵资源,且其适应性强,有较强的抗病、抗寒及抗热性,在百合杂交育种中具有特殊意义。更多还原

【Abstract】 Lilium pumilum DC, also known as lilium tenuifolium, is perennial herbs belonging to Lilium sp. in Liliaceae. With a special taxonomic and many superior characteristics,L. pumilum is an important genetic resource for lily breeding and breed improvement. There are abundant germplasm resources of native L. pumilum in China. It has important significance for protection and innovation of germplasm resources, and lily breeding, which was collection of resources, studying on genetic variation of population under the ecological factor, such as different geographical location, ecological environment and climate condition, and finding out the adverse resistance. The germplasm resources of native L. pumilum were researched systematically in morphology, palynology, chromosme Karyotype, molecular marker, adversity resistance, and the crossbreeding were carried out preliminarily. The main results were as follows:1. By introduction and cultivation of Lilium pumilum, the differences within populations were greater than that among twenty five L. pumilum populations, the differences were mainly in the morphological characters, including hair of flower bud, leaf wideth, plant height, flower color, etc. There were significant or very significant correlation between the characters of leaf wideth, anther wideth, flower diameter and the geographical factors (longitude, latitude, elevation). The correlation analysis showed that character variations would be the result of joint action of heredity and environment. The pollen morphology were observed with the scanning electron microscope, the results showed that the pollen grain of L. pumilum was single, nearly elliptic in shape, with one germination groove on its surface. Variability coefficient of pollen traits within populations was greater than that among populations.2. Karyotype analysis revealed the diversity among populations. Every populations of L. pumilum were diploid, with basic chromosome number 12. In root tip cells, Chromosome numbers was mostly 2n=2x=24, In addition, there were aneuploid somatic cells attached 1-3 accessory chromosome. Chromosome types of L. pumilum included st, sm, t, m and T. The ratio of the longest chromosome/the shortest chromosome was from 1.73 to 5.90, mostly in the range from 2 to 4; asymmetry coefficient was between 75.6% and 89.6%; By karyotype analysis, six types could be divided:3B,4B,3A,4A,3C,4C, and 3B was the most type, which was 56%.3. SSR analysis showed 93.5% polymorphic loci percentage of intra-species was obtained from 25 lily populations using 12 pairs of primers. Ratio of polymorphic bands among populations ranged from 78.55% to 91.92%, with the average being 82.36%, which indicated that native populations had rich genetic diversity revealed by EST-SSR molecular marker. The results were in good agreement with those determined from morphology, pollen and karyotype. Based on number of allele (A), number of effective alleles(Ae), ShannonWiener’s diversity index(I)、observed heterozygosity(Ho), and expected heterozygosity (He), it draws the following conclusions:among twenty five populations, the genetic diversity of BSS populations was the highest, while XT populations was the lowest.4. Researches in adversity resistance of L. pumilum indicated that:Different population of L. pumilum has different anti-Fusarium oxysporum capacities, among the 25 populations, the most resistant populations in Tangshan and Gansu, and the weakest populations are Ningxia and Liaoning. L. pumilum could endure short-term low temperature -30℃; Under the higher temperature37℃, L. pumilum grow well, and could endure short-term high temperature 40℃; L. pumilum grow well in the soil of salt content lower than 0.3%, while they would be injured in the soil of salt content highter than 0.3%; L. pumilum was suitable for planting at shade degree from 30% to 60%.5. The best medium for pollen culture of L. pumilum was suerose5% and H3BO3 10%. Pollen germination rate of L. pumilum was still 50.5% at -20℃for 120d. By regular pollination, the higher cross compatibility of combinations was L. pumilum×’seberia’. It could improve fruit setting ratio by delaying pollination, cut-style pollination, and application of NAA to the combinations between and ’seberia’,’White Heaven’,’Elite’.As a result, L. pumilum was widely distributed in the provinces of North China. There was abundant genetic variation on morphology, pollen, karyotype and DNA molecular level within and between the species, so as an valuable resource for lily breeding, L. pumilum has special significance in lily cross breeding in China.更多还原