湿地植物大花百合种群的性系统特征

开花植物性系统特征是植物在长期适应进化过程中逐渐形成的繁殖策略, 它在一定程度上影响了物种的种群结构及其在生境中的分布格局, 因此性系统特征一直是植物进化与生态学领域的研究热点。本研究于2012年和2020年在吉林省金川泥炭沼泽湿地, 通过样地调查取样的方法, 研究了湿地植物大花百合(Lilium concolor var. megalanthum)的性系统特征以及不同性别表型植株的比例、密度及空间分布格局, 并探究了大花百合植株个体大小和其性别表达的联系, 比较了不同性别表型的花粉实际可育性和来源不同的花粉授粉处理结实后的种子活力。结果显示, 个体水平上, 大花百合具有雄花植株、两性花植株和雄花两性花同株(即雄全同株) 3种性表型; 种群水平上, 具有雄花的个体充当父本, 通过花粉向下一代传递基因, 而具有两性花的个体主要充当母本, 通过胚珠实现基因的传递。2020年大花百合雄花植株占种群内开花植株的39.14%, 相比2012年雄花植株比例增加了22.80%; 大花百合种群分布密度为0.06株/m², 较2012年下降了0.09株/m²。从2012年到2020年, 总体表现为种群密度降低, 雄花植株相对比例增加的趋势。两性花植株和雄花植株在小尺度范围主要呈聚集分布, 随着尺度增大, 趋于随机分布。雄花植株显著小于两性花植株, 但鳞茎资源分配显著高于两性花植株。大花百合植株的性表达遵循大小依赖的性分配假说: 个体较小的植株表达为雄花植株, 而个体较大的植株则为两性花植株或雄全同株。在不同授粉处理下的结籽率和种子萌发结果表明, 大花百合自花授粉结籽率和坐果率显著低于异花授粉, 雄花植株和两性花植株花粉可育性以及对两性花植株授粉后所获得种子活力无显著差异。大花百合雄花植株的出现可能是对有限环境资源条件适应的结果, 反映了湿地条件下该植物在生长和繁殖资源之间的权衡策略, 在长期的湿地演变过程中, 这种性系统特征的出现具有一定的适应性意义。     

离体条件下2种除草剂诱导泸定百合多倍体的比较研究

在离体条件下,以野生泸定百合(Lilium sargentiae)不定芽(2n=2x=24)为材料,以无菌水(CK)和秋水仙素为对照,分别用不同浓度(100、200、300μmol/L)除草剂(氟乐灵、二甲戊灵)溶液分别浸泡(12h、24h、36h)处理,通过根尖细胞染色体数和叶片下表皮保卫细胞及叶片形态特征观察,比较2种除草剂不同浓度及不同处理时间对泸定百合多倍体诱导的效果。结果表明:300μmol/L二甲戊灵浸泡36h,变异率达30.0%,200μmol/L氟乐灵浸泡36h,变异率达32.2%,但2种诱变剂处理后材料诱导变异和存活率的差异不显著。对变异材料通过细胞学鉴定,发现2种诱变剂均能够诱导出四倍体泸定百合,但与秋水仙素处理相比,2种诱变剂处理时间短,材料死亡率低,变异率较高,而且对人畜伤害小,成本低;此外,与二倍体植株相比,四倍体植株的叶片气孔显著增大、气孔密度显著降低。研究认为,除草剂二甲戊灵和氟乐灵可作为秋水仙素诱导多倍体的替代品,而且叶片气孔大小可作为初步快速检测多倍体的有效指标。     

Proteomic analysis reveals the differential histone programs between male germline cells and vegetative cells in Lilium davidii

In flowering plants, male germline fate is determined after asymmetric division of the haploid microspore. Daughter cells have distinct fates: the generative cell (GC) undergoes further mitosis to generate sperm cells (SCs), and the vegetative cell (VC) terminally differentiates. However, our understanding of the mechanisms underlying germline development remains limited. Histone variants and modifications define chromatin states, and contribute to establishing and maintaining cell identities by affecting gene expression. Here, we constructed a lily protein database, then extracted and detailed histone entries into a comprehensive lily histone database. We isolated large amounts of nuclei from VCs, GCs and SCs from lily, and profiled histone variants of all five histone families in all three cell types using proteomics approaches. We revealed 92 identities representing 32 histone variants: six for H1, 11 for H2A, eight for H2B, five for H3 and two for H4. Nine variants, including five H1, two H2B, one H3 and one H4 variant, specifically accumulated in GCs and SCs. We also detected H3 modification patterns in the three cell types. GCs and SCs had almost identical histone profiles and similar H3 modification patterns, which were significantly different from those of VCs. Our study also revealed the presence of multiple isoforms, and differential expression patterns between isoforms of a variant. The results suggest that differential histone programs between the germline and companion VCs may be established following the asymmetric division, and are important for identity establishment and differentiation of the male germline as well as the VC.     

基于UPLC-Q-TOF-MS法分析百合珠芽化学成分及其薯蓣皂苷元抗肿瘤活性研究

为建立超高效液相色谱-四级杆飞行时间质谱(UPLC-Q-TOF-MS)快速鉴定百合珠芽中10种化学成分的分析方法,并对薯蓣皂苷元进行抗肿瘤研究。实验采用Thermo Hypersil Gold C₁₈柱(100 mm×2.1 mm,1.9μm);乙腈(A)-0.5%乙酸(B)为流动相,梯度洗脱;电喷雾离子源(ESI),正负离子同步监测。采用CCK8法进行薯蓣皂苷元抗肺肿瘤A549细胞、胃肿瘤HGC-27细胞的药效筛选。结果表明,通过二级高分辨质谱分析结合相关文献,共鉴定对香豆酸、薯蓣皂苷、槲皮素等10个化合物。药理研究显示,薯蓣皂苷元对肺癌A549细胞增殖只有微弱的抑制活性,而对胃癌HGC-27细胞增殖表现出较强的抑制作用。本试验证实UPLC-Q-TOF-MS/MS可从保留时间、紫外吸收光谱、精确相对分子质量、分子式和二级结构碎片等方面对百合珠芽的主要成分进行定性分析,为寻找百合珠芽中活性物质提供一种快速准确的分析方法,且揭示百合珠芽中鉴定得到的单体成分可能具有较强的抗肿瘤活性。     

Factors influencing T-DNA transferring into pollen of lily in vitro

Direct pollen transformation method improves the classical transformation procedures because some tissue culture steps and subsequent regeneration can be avoided. A critical step in the development of Agrobacterium-mediated transformation is the establishment of optimum conditions for T-DNA delivery into tissue. The pollen grains of David lily (Lilium davidii Duchartre) are transformable by Agrobacterium during their germination, and extremely high GUS expression frequency of pollen had been achieved (92.7 ± 2.7%), but not for the ungerminated pollen. The culture medium, Agrobacterium cell density, duration of co-cultivation, and the combination of bacterial strains and plasmids should be optimized to get the highest transformation frequency. Thus, a method for pollen monocotyledonous species reproductive tissues transformation by Agrobacterium in monocots has been successfully developed. Published in Russian in Fiziologiya Rastenii, 2007, Vol. 54, No. 3, pp. 475–480 The text was submitted by the authors in English.     

Changes in the composition of ionogenic groups of the wall of the lily pollen grain during germination

Changes in the composition of ionogenic groups of the polymeric matrix of the cell walls of lily (Lilium longiflorum Thunb.) pollen grains were studied during its activation at the early stages of pollen germination. In the cell walls isolated from nonactivated and activated pollen grains, four types of ionogenic groups were identified: amino groups, carboxylic groups of uronic acids, phenolic OH-groups. and groups with pK_a 7–8. During the early stages of germination, ionization constants of each type groups remained unchanged, but the quantitative composition of ionogenic groups in the intine changed. In this matrix, a decrease in the content of phenolic groups and demethylated carboxylic groups of uronic acids was detected. It is supposed that, at early stages of germination, the intine loses some part of acid pectins and some phenolic compounds.     

亚洲百合花丝离体培养器官形成的细胞形态学研究

对亚洲百合的花丝进行离体培养,并利用常规石蜡制片技术对诱导效果最好的材料进行细胞形态学观察,研究花丝在离体培养过程中器官形成的细胞形态学变化。结果表明:花丝在MS+BA0.5 mg/L+NAA0.5 mg/L的培养基上诱导效果最好。离体培养后其形态学下端切口内方的1～3层细胞首先启动脱分化,然后是内方的10～12层细胞,而其他部位的细胞自始至终未启动脱分化。亚洲百合的再生方式为器官发生型,器官通过胚性愈伤组织间接产生,在胚性愈伤组织团表面附近形成芽原基,或在胚性愈伤组织团内部形成根原基,有时同时分别在内、外形成根原基和芽原基后再通过维管组织连接成完整的植株。本研究为亚洲百合的人工调控提供基础理论依据。     

Covalently bound wall proteins of pollen grains and pollen tubes grown in vitro and in styles after self- and cross-pollination in Lilium longiflorum

Summary A method was worked out using trifluoromethanesulfonic acid (TFMS) as a reagent to split the covalently bound proteins, which are NaCl insoluble, from pollen tube walls of Lilium longiflorum, leaving the peptide bonds essentially intact. After electrophoretic separation, comparisons were made among these proteins from pollen grains and pollen tubes grown in vitro and in styles after self- and cross-pollination. It was found that a) the patterns of covalently bound wall proteins were different between tubes grown in vitro and in vivo; b) fewer bands were found in covalently bound wall proteins than that in noncovalently bound proteins; c) the bands remained almost the same no matter whether the tubes had been cross pollinated or self pollinated, indicating that while the noncovalently bound proteins were involved in incompatibility as shown in the previous paper, the covalently bound proteins may only serve as a structural component, having little to do with incompatibility.     

用酶解方法观察卷丹的贝母型胚囊发育过程

酶法分离技术作为观察胚囊发育的一种简捷技术已经应用于不少植物。然而,百合科植物迄今未见类似报道。最近,作者以卷丹为实验材料观察了大孢子发生和雌配子体发育,表明这一技术对于具有贝母型四孢子胚囊发育特点的百合属植物是同样适用的。