Evidence for natural hybridization between Primula beesiana and P. bulleyana,two heterostylous primroses in NW Yunnan,China

Natural hybridization was assumed to play an essential role for the diversification of Primula; however, only one study of hybridization in the region of the Himalayas has been undertaken. In the present study, we examined another natural hybrid zone where morphologically putative hybrids as well as P. beesiana Forrest, P. bulleyana Forrest, and P. poissonii Franch. co-occurred. We used molecular data to confirm the parental species of putative hybrids and the unidirectional hybridization pattern between P. beesiana and P. bulleyana. Moreover, with reference to synthetic F₁s, most hybrids examined are possibly advanced generations, although the possibility of F₁ hybrids currently examined could not be completely excluded. In addition, pollinator observations on experimental arrays of transplanted parental species showed interspecific pollen flows during visitations of shared pollinators, indicating an incomplete pre-zygotic barrier between P. beesiana and P. bulleyana. Seed productions from both flower morphs of putative hybrids were significantly lower than parental species, suggesting lower reproductive success in these hybrids. Combined with the evidence of recent habitat disturbance in the study area, we might witness the early process of hybridization between P. beesianaand P. bulleyana.     

四种野生报春花种子萌发生物学特性

以多脉报春Primula polyneura、钟花报春P. sikkimensis、桔红灯台报春P. bulleyana 和粉被灯台报春P. pulverulenta 的种子为材料,研究其形态及光照、GA3 对种子萌发的影响。结果表明,4 种报春花种子形态各异,钟花报春种子质量最大,千粒重达0.458 g,粉被灯台报春种子质量最小,千粒重为0.192 g。光照处理及不同浓度GA3 处理对4 种报春花种子萌发的影响存在差异。光照对多脉报春的萌发效果最好,其次为钟花报春与桔红灯台报春,对粉被灯台报春无明显促进作用。光照条件下,400 mg·L^-1 GA3 处理对桔红灯台报春和粉被灯台报春的萌发效果较好,发芽率显著提高,发芽持续时间缩短;钟花报春萌发适宜的GA3浓度为200 mg·L^-1。     

Comparative study of pollination biology of two closely related alpine Primula species,namely Primula beesiana and P. bulleyana (Primulaceae)

Abstract The comparative pollination biology of a population of Primula beesiana, a population of P. bulleyana, and an overlapping population of these two species in Yulong Shan, Yunnan Province, China, was studied in 2004 and 2005. The results indicate that both P. beesiana and P. bulleyana are typical heterostylous and obligate outcrossing species; the main pollinators of the two species were bees and butterflies. At the sites of all three populations, the main pollinating visitors of the two species showed preference for one of the two species, resulting in the ethological isolation of the two species by the pollinators. This ethological isolation contributes to the reproductive isolation of the two species, which supports the hypothesis that P. beesiana and P. bulleyana are two distinct species. The reproductive isolation of the two species (ethological isolation) is probably an important mechanism in maintaining species boundaries in the genus and has contributed to the species diversification of Primula in the area. In addition, gene exchanges between P. beesiana and P. bulleyana has occurred to some extent in the overlapping population, but whether natural hybridization has contributed to species diversification in Primula remains to be determined.     

木里报春一新异名

将新近发表的Primula hongshanensis D. W. H. Rankin, Z. D. Fang &; H. Sun处理为木里报春P. boreiocalliantha的异名, 对近缘的几个种列出了检索表。     

特有珍稀濒危植物景东报春遗传多样性的ISSR分析(英文)

景东报春(Primula interjacens Chen)是一分布在中国云南中南部的稀有的、分布区狭窄的特有种。该种含2个变种:原变种景东报春(P.interjacens Chen var.interjacens),现存一个居群;和光叶景东报春(P.interjacens Chen var.epilosa C.M.Hu),有2个居群。本文用ISSR分子标记对景东报春现存的3个居群进行了遗传多样性分析。和我们最初的预计相反,尽管居群小、分布区狭窄,景东报春的遗传多样性却很高(在居群水平的多态位点率P=59.75％,基因多样性H_E=0.2368,Hpop=0.3459:在种的水平的多态位点率P=75.47％,遗传多样性H_T=0.3205,总的遗传多样性Hsp=0.4618)。推测异型花和杂交可能是维持高的遗传多样性的原因。Nei的遗传多样性水平(26.13％)和Shannon多样性指数(25.09％)显示居群间存在中度分化。尽管景东报春原变种和变种在形态上有区别,但用非加权配对算数平均法(UPGMA)聚类分析的结果表明,两者并没有明显的遗传分化,可处理为一个单一的分类单元。基于观察到的居群遗传信息,建议采取就地保护和迁地保护的保护措施。     

安徽特有植物安徽羽叶报春的繁殖生物学研究

本文分别从物候、繁育结构和传粉等方面研究了国家三级保护植物、安徽特有种--安徽羽叶报春(Primula merrilliana)的繁殖生物学特征。研究结果表明: (1) 安徽羽叶报春是典型的形态和功能意义上的花柱二型的二年生植物, 其始苗期为9月, 一直持续到第二年6月底或7月初死亡, 各居群长柱花植株比短柱花植株开花略早3–5 d; (2) 安徽羽叶报春的散孔型花粉显示其在报春花属中有重要的系统意义和进化意义。同时, 短柱花花粉量比长柱花少, 但其花粉直径是后者的1.78倍左右; (3) 长花柱的雌蕊长度是短花柱的1.64倍, 而且其柱头上的乳头状突起比短花柱上的长而稀; (4) 3个研究居群的P/O比都不相同, 我们发现花粉量比胚珠数量有更大的变异, 这可能与生境有关; (5) 安徽羽叶报春为异花授粉植物, 蓟马属(Thrips)昆虫为其重要的传粉者, 其同型花授粉可育性远比异型花授粉的高; (6) 其长、短柱型种子没有明显的形态差异, 多属不等边七面体, 少为其他多面体。据研究, 在小居群中两种花柱类型植株的比例失衡, 生境的破坏和伴生种的消失可能是导致安徽羽叶报春濒危的重要原因。     

报春花属滇海水仙花开花传粉特性研究

通过田间观察,运用杂交指数、花粉及柱头活力、花粉/胚珠比、坐果率等指标,对滇海水仙花人工种群的花部特征、开花动态及授粉特性等进行研究。在人工栽培条件下,滇海水仙花花期为12月至翌年2月,单株花期30～45 d,单花花期为9～14 d,花朵有长花柱花和短花柱花之分。滇海水仙花的传粉昆虫主要是蜜蜂,此外还有蝴蝶和蝇类,其繁育系统为兼性自交。     

特有珍稀濒危植物景东报春遗传多样性的ISSR分析

景东报春(Primula interjacens Chen)是一分布在中国云南中南部的稀有的、分布区狭窄的特有种.该种含2个变种:原变种景东报春(P.interjacens Chen var.interjacens),现存一个居群;和光叶景东报春(P.interjacens Chen var.epilosa C.M.Hu),有2个居群.本文用ISSR分子标记对景东报春现存的3个居群进行了遗传多样性分析.和我们最初的预计相反,尽管居群小、分布区狭窄,景东报春的遗传多样性却很高(在居群水平的多态位点率P=59.75%,基因多样性HE=0.236 8,Hpop=0.345 9;在种的水平的多态位点率P=75.47%,遗传多样性HT=0.320 5,总的遗传多样性Hsp=0.4618).推测异型花和杂交可能是维持高的遗传多样性的原因.Nei的遗传多样性水平(26.13%)和Shannon多样性指数(25.09%)显示居群间存在中度分化.尽管景东报春原变种和变种在形态上有区别,但用非加权配对算数平均法(UPGMA)聚类分析的结果表明,两者并没有明显的遗传分化,可处理为一个单一的分类单元.基于观察到的居群遗传信息,建议采取就地保护和迁地保护的保护措施.     

陕西羽叶报春的人工栽培技术

陕西羽叶报春是百年绝迹、曾被植物界视为已经灭绝或可能灭绝的植物,开展人工栽培研究,对于保护这一极危物种,实现园林开发都具有重要意义。介绍了陕西羽叶报春人工栽培方法,供参考。     

滇北球花报春和滇海水仙花的光合特性研究

用LI-6400便携式光合测定仪对引种栽培的滇北球花报春和滇海水仙花的光合参数进行测定,以探讨其光合生理特性.结果表明:(1)滇北球花报春的净光合速率(P_n)和蒸腾速率(T_r)日进程曲线均呈"单峰"型,它们的峰值分别出现在13:00和16:00;滇海水仙花的P_n、Tr较滇北球花报春低,且在一定范围内保持稳定,没有明显的峰值,与滇北球花报春表现出较明显的种间差异;(2)两种报春比叶重( LMA)和叶氮含量(LNC_a)对其光合相关特征参数没有显著影响,而叶氮在Rubisco中的分配系数PR、生物能库中的分配系数P_B和光合组分中总氮含量N_P与光合特征参数LCP、V_(cmax)、J_(max)、CE具有显著的正相关关系;(3)滇北球花报春具有较高的气孔导度(G_s)、P_n和T_r,对强光、高温、低湿度表现出较强的环境适应性,表现出较强的光合能力.     

Primula vallicola sp. nov. (Primulaceae) from Sichuan,China

A new species of Primula, P. vallicola Y. Xu, G. Hao & C.M. Hu, is described and illustrated from Sichuan province, China. Based on general morphology the new species is assigned to Primula sect. Aleuritia subsect. Yunnanensis. It is closely allied to P. kialensis, but can be distinguished by its larger stature, leaf shape, and the well‐differentiated petiole. The leaf shape of the new species is ovate to ovate‐elliptic and usually sub‐rounded at base. The new species also resembles P. homogama, but differs in being glabrous rather than with appressed hairs, and with longer petiole.     

Characterization of 24 microsatellite markers in Primula chungensis (Primulaceae), a distylous homostylous species,using MiSeq sequencing

Primula chungensis is a species with considerable floral and mating-system variation, including distylous (outcrossing), homostylous (selfing) and mixed populations that contain both outcrossing and selfing forms. We isolated 24 microsatellite markers from P.chungensis using Illumina MiSeq sequencing. Polymorphism and genetic diversity were then measured based on a sample of 24 individuals from a natural population in southern Tibet. All loci were polymorphic with the number of alleles per locus ranging from 2 to4. The observed and expected heterozygosity ranged from 0 to 1 and 0.219 to 0.708, respectively. The microsatellite markers we have identified will serve as valuable tools for the investigation of the population genetic structure and phylogeography of P.chungensis and will inform models of the evolutionary history of mating systems in the species.     

On the occurrence of unilateral incompatibility in Primula section Aleuritia Duby and the origin of Primula scotica Hook

The occurrence of unilateral incompatibility was tested for a distylous heteromorphic system, using crosses between a self-sterile and three self-fertile species in Primula L. section Aleuritia Duby. The crosses showed non-reciprocity but not in the same direction as would be predicted in the case of unilateral incompatibility. Pollen from the self-compatible (s-c) species was not always inhibited on the style of the self-incompatible (s-i) species, and cross-fertility between s-i and s-c crosses more resembled that between different s-c species, which was also non-reciprocal. Cytoplasmic-nuclear DNA interactions and the possibility of embryo-endosperm imbalance could both explain these results. In crosses between Primula farinosa L. (s-i diploid) and P. scotica Hook. (s-c hexaploid), heterostylous pin tetraploid offspring were produced. This result is discussed in relation to the genome of P. scotica and the possibility that pin morph plants may occur in wild P scotica populations.     

Effects of population size on reproductive success of the endangered and endemic species Primula merrilliana

The reproductive ability related to the population size of the endangered and endemic species Primula merrilliana Schltr.was investigated.In 26 populations observed,only four contain more than 500 flowering individuals,whereas most of them(53.8%) consist of less than 100 flowering individuals.Though the ratio of pin and thrum plants keeps its balance at 1:1 for all populations,the frequency of pin and thrum flowers was significantly biased in most small populations.Population size strongly affected reproductive success; plants in small populations produced significantly fewer flowers and fruits per plant and fewer seeds per fruit,and therefore fewer seeds per plant.The floral density was another important factor that influenced the reproductive success of P.merrilliana,because four main reproductive success parameters (fruits per plant,seeds per fruit,seeds per plant,and the proportion of flowers setting fruit) were all positively correlated with floral density.The size of plants and the number of leaves per plant (measure of habitat quality) were not influenced by the variation of population size,suggesting that the reduced fecundity in small populations may not be a consequence of lower habitat quality,inbreeding depression and pollen limitation as a result of less attractiveness in small populations are therefore likely explanations for these patterns.     

Pollen flow in a population of Primula vulgaris Huds.

A British population of Primula vulgaris was visited four times between 1971 and 1976 for study of the nature and functioning of distyly. The stainability and production of pollen from pins exceeded those of thrums. About 20% of pin pollen and 48% of thrum pollen was removed from anthers by insect visitors. Pins and thrums were present in a 1:1 ratio in 1971 but pins outnumbered thrums in 1976. Thrums produced more seeds per flower than pins though the number of ovules produced by each was similar. Two methods for collecting stigmas from open flowers and analyzing them for pollen loans produced somewhat different results. For pin stigmas, the pollen load consisted of 2–23% thrum pollen; for thrum stigmas, the pollen load consisted of 0–71% pin pollen with most stigmas having less than 50% pin pollen. In general, intermorph pollen flow is less than would be expected if pollen flow were random. It is probable that most intramorph pollen on stigmas is a result of self- or geitonogamous pollination. The extensive literature concerning the natural pollinators of the primrose is reviewed. Although Darwin's hypothesis concerning the functional significance of distyly in promoting intermorph pollination was never quantified, the pollen flow patterns observed in P. vulgaris are unexpectedly deviant and are similar to those patterns observed in several unrelated heterostylous species in other plant families.     

报春花属藏报春组、毛茛叶报春组的界定和系统发育关系 :核糖体DNAITS序列证据(英文)

报春花属 (PrimulaL .)藏报春组 (sect.AuganthusPaxexBalf.f.)和毛茛叶报春组 (sect.RanunculoidesChenetC .M .Hu)的界定一直是没有解决的问题。应用核糖体DNAITS序列数据探讨其系统发育关系。取样包括藏报春组和毛茛叶报春组的全部 5个种以及其他一些相关组的代表种。ITS系统树表明 ,陕西羽叶报春 (P .filchneraeKnuth)应与藏报春 (P .sinensisSabineexLindl.)和野藏报春 (P .rupestrisBalf.f.etFarrer)一起置于藏报春组 ;毛茛叶报春组只含两种 :毛茛叶报春 (P .cicutariifoliaPax)和安徽羽叶报春 (P .merrillianaSchltr.)。这两组并不具密切亲缘关系 ,它们在报春花属中与其他组的关系还需进一步研究。研究也表明ITS序列可以为报春花属的系统发育重建提供大量可靠资料     

安徽羽叶报春与毛茛叶报春的遗传多样性研究与新资源评估

采用RAPD方法对分布于安徽的珍稀濒危植物安徽羽叶报春(Primula merrilliana Schltr.)和毛茛叶报春(P．cicutariifolia Pax)的10个居群进行了DNA基因组多态性分析,从50条10碱基随机引物中筛选出14条能扩增出稳定性和重复性好的DNA片段的引物,共扩增出85条带,其中多态性带67条,占总数的78．8％。安徽羽叶报春与毛茛叶报春的多态位点分别达到71．6％与66．7％,因而推测主要致濒因素可能不是通常认为的低水平的遗传多样性。采用N—J法对遗传距离构建的树状图进行聚类分析,从分子角度证明了安徽羽叶报春与毛茛叶报春是2个自然的物种,同时也说明了它们的遗传多样性与生境多样性的密切相关性。由于这2个物种具有地处黄山风景区的地理优势和花朵多、花期长、花姿优美等观赏性特点以及遗传优势,如加以合理的开发与利用,可以作为观赏花卉新资源。     

报春花属植物的育种研究进展

本文对报春花属植物引种的历史和现状、育种途径和育种成果进行了综述.报春花属是报春花科最大的属,全世界约500余种,我国有296种.国外在杂交育种、多倍体育种、组织培养和体细胞融合等方面取得了许多研究成果,而国内有关报春花属植物育种的研究相对较少.目前通过杂交育种或多倍体育种等手段已培育出众多花色丰富、花型各异或不含报春碱的报春花新品种.今后我国应在保护种质资源的基础上,加强报春花新品种的培育,并尽快实现产业化生产.     

Development and characterization of 24 microsatellite markers in Primula tosaensis,an endangered primrose,using MiSeq

Primula tosaensis (Primulaceae) is an endangered primrose endemic to Japan. In this study, 24 novel microsatellite markers were developed using Illumina MiSeq sequencing to facilitate conservation of this endangered species. The genetic diversity and polymorphisms of these novel markers were measured in 32 individuals from a wild P. tosaensis population. The number of alleles and expected heterozygosities ranged from 2 to 5 (mean = 2.8) and from 0.119 to 0.724 (mean = 0.395), respectively. All loci were in Hardy–Weinberg equilibrium. The markers developed in this study will provide a powerful and practical tool for investigating the population structure and genetic diversity of P. tosaensis.     

五种野生观赏报春花引种驯化初报

报道了采自云南西北部的5种野生报春(灰岩皱叶报春Primula forrestii Franck,海仙花P,poissonii Franck,橘红灯台报春P.bulleyanan Forr.,偏花报春P.secundiflora Franch和钟花报春P.sikkimensis Hook)的引种驯化研究。将采自不同地方,不同气候以及不同生态环境下的种子,通过在不同控制条件下包括基质、温度、光照等“从种子到种子”整个过程的实验观察,得出结果如下：(1)虽然每个种的种子在不同的基质中萌发率参差不齐,但所有种子在昆明栽培条件下都有高的萌发适应性。(2)虽然它们的开花时间不同(海仙花和偏花报春除外),但所有从播种获得的植株要10—16个月才能开花,与野生报春相比栽培的报春花花期提前2—3个月,灰岩皱叶报春还出现了重瓣花。(3)苗圃的报春花结实率比在野生状态下的低,人工授粉后座果率有所提高。