偏花报春和海仙报春3个同域居群的不对称杂交

doi:10.17520/biods.2017001

摘要/Abstract

摘要：

自然杂交是进化生物学研究中的热点, 而杂交方向则是理解自然杂交和生殖隔离机制的一个关键环节。偏花报春(Primula secundifora)和海仙报春(P. poissonii)在横断山区重叠分布且存在自然杂交现象, 研究仅证实了种间杂交的发生, 但对不同地域的这2个物种间的杂交方向并未开展深入研究。本研究选取偏花报春和海仙报春3个同域分布点的居群, 利用双亲遗传的核转录间隔区ITS和母系遗传的叶绿体片段trnH-psbA构建系统树, 检测了3个居群中的自然杂交以及杂交方向; 通过人工授粉实验检测种内种间杂交以及不同物种作为母本时对结籽数的影响水平。DNA分子标记结果显示每个居群中的杂交方向都是不对称的, 海仙报春更容易在杂交中作为母本。人工授粉的结果表明种内种间交配以及哪个种作为母本对结籽数有非常显著的影响。海仙报春作为母本时能够显著提高结籽数。这2个物种之间不同的生殖隔离强度可能是造成不对称杂交的原因。3个居群中都是以海仙报春更易作母本, 可能是因为这3个地点的种间生殖隔离具有相似的机制。

关键词: 报春花属, 同域分布, 杂交方向, 不对称

Abstract

Natural hybridization is one of the research hotspots in evolutionary biology. The direction of hybridization is a critical aspect to understanding natural hybridization and interspecific reproductive isolation. Although natural hybridization between Primula secundiflora and P. poissonii has been confirmed in overlapping areas in the Hengduan Mountains, the interspecific hybridization directions among different populations remain unclear. We chose three sympatric populations to test interspecific hybridization directions. Biparentally inherited nuclear internal transcribed spacer (ITS) and maternally inherited chloroplast sequence trnH-psbA techniques were used to confirm hybridization and to test directions. Moreover, hand pollination of intraspecies and interspecies populations were performed to detect which factors influence seed numbers and hybridization patterns. Results of DNA marker analysis suggested that the direction of hybridization was asymmetric in each population, and P. poissonii was found to be the most maternal parent. Intraspecific crossing produced significantly more seeds than interspecific crossing. Primula poissonii produced significantly higher seed numbers when it was treated as the maternal parent. The asymmetric direction may be the result of the asymmetric strength of reproductive barriers between P. secundiflora and P. poissonii. Similar mechanisms of reproductive isolation may contribute to the asymmetric hybridization among the three sympatric sites.

Key words: Primula, sympatric distribution, hybridization direction, asymmetric

谢艳萍, 赵建立, 朱兴福, 李莉, 李庆军 (2017) 偏花报春和海仙报春3个同域居群的不对称杂交. 生物多样性, 25, 647-653. DOI: 10.17520/biods.2017001.

Yanping Xie, Jianli Zhao, Xingfu Zhu, Li Li, Qingjun Li (2017) Asymmetric hybridization of Primula secundiflora and P. poissonii in three sympatric populations. Biodiversity Science, 25, 647-653. DOI: 10.17520/biods.2017001.

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链接本文: https://www.biodiversity-science.net/CN/10.17520/biods.2017001

https://www.biodiversity-science.net/CN/Y2017/V25/I6/647

图/表 5

图1 香格里拉格咱乡(GZ)、普达措国家公园(PTS)和香格里拉高山植物园(SABG) 3个海仙报春和偏花报春居群的地理位置

Fig. 1 Locations of the three populations from Geza Village (GZ), Potatso National Park (PTS) and Shangri-La Alpine Botanical Garden (SABG) in Shangri-La

图2 海仙报春(A)、杂交个体(B)和偏花报春(C)核转录间隔区ITS序列中的双峰结构

Fig. 2 Double waves on part of internal transcribed spacer (ITS) sequences in Primula poissonii (A), Hybrids (B) and P. secundiflora (C)

表1 叶绿体片段trnH-psbA中杂交个体和亲本存在变异的位点及位置

Table 1 Positions at which hybrids and parents differ in the trnH-psbA sequence

居群 Population	物种 Species	个体数 No. of individuals	trnH-psbA变异位点及位置 Sequence region and position (bp) of trnH-psbA
居群 Population	物种 Species	个体数 No. of individuals	36 bp	63 bp	103 bp	112-386 bp
	海仙报春 Primula poissonii	7	G	C	A	1*
	偏花报春 P. secundiflora	7	A	A	T	2*
格咱 Geza Village (GZ)	杂交个体类型1 Hybrid type-1	6	G	C	A	1*
格咱 Geza Village (GZ)	杂交个体类型2 Hybrid type-2	4	A	A	T	2*
香格里拉高山植物园 Shangri-La Alpine Botanical Garden (SABG)	杂交个体类型1 Hybrid type-1	2	G	C	A	1*
普达措国家公园 Potatso National Park (PTS)	杂交个体类型1 Hybrid type-1	15	G	C	A	1*
普达措国家公园 Potatso National Park (PTS)	杂交个体类型2 Hybrid type-2	5	A	A	T	2*

图3 基于Bayes法构建的核转录间隔区ITS和叶绿体基因trnH-psbA系统树。GZ、PTS和SABG分别代表格咱乡、普达措国家公园和香格里拉高山植物园居群。

Fig. 3 The nuclear ITS and chloroplast trnH-psbA phylogeny tree based on Bayes method. GZ, PTS and SABG are the abbreviations of populations from Geza Village, Potatso National Park and Shangri-La Alpine Botanical Garden.

表2 种内种间交配对结籽数的影响

Table 2 Effects of cross-pollination treatments (within or between species and mother species) on seed production

来源 Source	Wald 卡方值	自由度	P值
	Wald Chi-Square	df	P-value
种内 vs. 种间 Within vs. between species (WBS)	61.110	1	< 0.001
海仙报春 vs. 偏花报春作母本 Primula poissonii vs. P. secundiflora as mother (PSM)	29.078	1	< 0.001
交互作用 Interaction (WBS × PSM)	22.074	1	< 0.001

参考文献 31

[32]	Richards J (2003) Primula. Timber Press Inc., Oregon.
[33]	Runyeon-Lager H, Prentice HC (2000) Morphometric variation in a hybrid zone between the weed, Silene vulgaris, and the endemic, Silene uniflora ssp. petraea (Caryophyllaceae), on the Baltic Island of Öland. Canadian Journal of Botany, 78, 1384-1397.
[34]	Sang T, Crawford DJ, Stuessy TF (1997) Chloroplast DNA phylogeny, reticulate evolution, and biogeography of Paeonia (Paeoniaceae). American Journal of Botany, 84, 1120-1136.
[35]	Stace CA (1975) Hybridization and the Flora of the British Isles. Academic Press, London.
[36]	Tang XL, Liu YM, Pan HT, Ma YL, Li XY, Zhang QX (2014) Intergeneric cross-compatibility between Primula forbesii (Section Monocarpicae) and Primula saxatilis (Section Cortusoides). Acta Botanica Boreali-Occidentalia Sinica, 34, 270-275. (in Chinese with English abstract)
	[唐星林, 刘艳梅, 潘会堂, 马玉磊, 李小远, 张启翔 (2014) 小报春与岩生报春种间杂交亲和性研究. 西北植物学报, 34, 270-275.]
[37]	Terzioglu S, Coskuncelebi K, Gultepe M (2012) Primula × uzungolensis (Primulaceae): a new natural hybrid from NE Anatolia. Turkish Journal of Botany, 36, 9-19.
[38]	Thompson JD, Gibson T, Higgins DG (2002) Multiple sequence alignment using Clustal W and Clustal X. In: Current Protocols in Bioinformatics (ed. Baxevanis AD). John Wiley & Sons, New York.
[39]	Tiffin P, Olson MS, Moyle LC (2001) Asymmetrical crossing barriers in angiosperms. Proceedings of the Royal Society B: Biological Sciences, 268, 861-867.
[40]	van der Velde M, Bijlsma R (2004) Hybridization and asymmetric reproductive isolation between the closely related bryophyte taxa Polytrichum commune and P. uliginosum. Molecular Ecology, 13, 1447-1454.
[41]	van Droogenbroeck B, Kyndt T, Romeijn-Peeters E, van Thuyne W, Goetghebeur P, Romero-Motochi JP, Gheysen G (2006) Evidence of natural hybridization and introgression between Vasconcellea species (Caricaceae) from southern Ecuador revealed by chloroplast, mitochondrial and nuclear DNA markers. Annals of Botany, 97, 793-805.
[42]	Wang XR, Szmidt AE, Savolainen O (2001) Genetic composition and diploid hybrid speciation of a high mountain pine, Pinus densata, native to the Tibetan Plateau. Genetics, 159, 337-346.
[43]	White TJ, Bruns T, Lee S, Taylor JW (1990) Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In: PCR Protocols: A Guide to Methods and Applications (eds Innis MA, Gelfand DH, Sninsky JJ, White TJ), pp. 315-322. Academic Press, New York.
[44]	Wu ZK, Zhang CQ (2010) Comparative study of pollination biology of two closely related alpine Primula species, namely Primula beesiana and P. bulleyana (Primulaceae). Journal of Systematics and Evolution, 48, 109-117.
[45]	Xiang LL, Werth CR, Emery SN, McCauley DE (2000) Population-specific gender-biased hybridization between Dryopteris intermedia and D. carthusiana: evidence from chloroplast DNA. American Journal of Botany, 87, 1175-1180.
[46]	Yu JJ, Kuroda C, Gong X (2014) Natural hybridization and introgression between Ligularia cymbulifera and L. tongolensis (Asteraceae, Senecioneae) in four different locations. PLoS ONE, 9, e115167.
[47]	Zha HG, Milne RI, Sun H (2008) Morphological and molecular evidence of natural hybridization between two distantly related Rhododendron species from the Sino-Himalaya. Botanical Journal of the Linnean Society, 156, 119-129.
[48]	Zha HG, Milne RI, Sun H (2010) Asymmetric hybridization in Rhododendron agastuma: hybrid taxon comprising mainly F1s in Yunnan, China. Annals of Botany, 105, 89-100.
[49]	Zhang JJ, Montgomery BR, Huang SQ (2016) Evidence for asymmetrical hybridization despite pre- and post-pollination reproductive barriers between two Silene species. Aob Plants, 8, plw032.
[50]	Zhou RC, Gong X, Boufford D, Wu CI, Shi SH (2008) Testing a hypothesis of unidirectional hybridization in plants: observations on Sonneratia, Bruguiera and Ligularia. BMC Evolutionary Biology, 8, 149.
[1]	Abbott R, Albach D, Ansell S, Arntzen JW, Baird SJE, Bierne N, Boughman J, Brelsford A, Buerkle CA, Buggs R (2013) Hybridization and speciation. Journal of Evolutionary Biology, 26, 229-246.
[2]	Anderson E (1948) Hybridization of the habitat. Evolution, 2, 1-9.
[3]	Arnold ES, Richards AJ (1998) On the occurrence of unilateral incompatibility in Primula section Aleuritia Duby and the origin of Primula scotica Hook. Botanical Journal of the Linnean Society, 128, 359-368.
[4]	Arnold ML (1997) Natural Hybridization and Evolution. Oxford University Press, New York.
[5]	Arnold ML, Ballerini ES, Brothers AN (2012) Hybrid fitness, adaptation and evolutionary diversification: lessons learned from Louisiana Irises. Heredity, 108, 159-166.
[6]	Balao F, Casimiro-Soriguer R, Luis GCJ, Terrab A, Talavera S (2015) Big thistle eats the little thistle: does unidirectional introgressive hybridization endanger the conservation of Onopordum hinojense? New Phytologist, 206, 448-458.
[7]	Barton NH, Hewitt GM (1985) Analysis of hybrid zones. Annual Review of Ecology and Systematics, 16, 113-148.
[8]	Broyles SB (2002) Hybrid bridges to gene flow: a case study in milkweeds (Asclepias). Evolution, 56, 1943-1953.
[9]	Carney SE, Gardner KA, Rieseberg LH (2000) Evolutionary changes over the fifty-year history of a hybrid population of sunflowers (Helianthus). Evolution, 54, 462-474.
[10]	Darriba D, Taboada GL, Doallo R, Posada D (2012) jModelTest 2: more models, new heuristics and parallel computing. Nature Methods, 9, 772.
[11]	Doyle JJ, Doyle JL (1987) A rapid DNA isolation procedure for small quantities of fresh leaf material. Phytochemical Bulletin, 19, 11-15.
[12]	Du GH, Zhang ZQ, Li QJ (2012) Morphological and molecular evidence for natural hybridization in sympatric population of Roscoea humeana and R. cautleoides (Zingiberaceae). Journal of Plant Research, 125, 595-603.
[13]	Ellstrand NC, Prentice HC, Hancock JF (1999) Gene flow and introgression from domesticated plants into their wild relatives. Annual Review of Ecology and Systematics, 30, 539-563.
[14]	Field DL, Ayre DJ, Whelan RJ, Young AG (2011) The importance of pre-mating barriers and the local demographic context for contemporary mating patterns in hybrid zones of Eucalyptus aggregata and Eucalyptus rubida. Molecular Ecology, 20, 2367-2379.
[15]	Guindon S, Gascuel O (2003) A simple, fast and accurate method to estimate large phylogenies by maximum- likelihood. Systematic Biology, 52, 696-704.
[16]	Hall TA (1999) BioEdita user-friendly biological sequence alignment editor and analysis program for Windows 95/98/ NT. Nucleic Acids Symposium Series, 41, 95-98.
[17]	Huelsenbeck JP, Ronquist F (2001) MRBAYES Bayesian inference of phylogenetic trees. Bioinformatics, 17, 754-755.
[18]	Jensen AB, Palmer KA, Boomsma JJ, Pedersen BV (2005) Varying degrees of Apis mellifera ligustica introgression in protected populations of the black honeybee, Apis mellifera mellifera, in Northwest Europe. Molecular Ecology, 14, 93-106.
[19]	Kress WJ, Wurdack KJ, Zimmer EA, Weigt LA, Janzen DH (2005) Use of DNA barcodes to identify flowering plants. Proceedings of the National Academy of Sciences, USA, 102, 8369-8374.
[20]	Levin DA, Francisco-Ortega J, Jansen RK (1996) Hybridization and the extinction of rare plant species. Conservation Biology, 10, 10-16.
[21]	Li XJ, Wang LY, Yang HL, Liu JQ (2007) Confirmation of natural hybrids between Gentiana straminea and G. siphonantha (Gentianaceae) based on molecular evidence. Acta Botanica Yunnanica, 29, 91-97. (in Chinese with English abstract)
	[李小娟, 王留阳, 杨惠玲, 刘建全 (2007) 麻花艽和管花秦艽(龙胆科)之间自然杂交类型的分子验证. 云南植物研究, 29, 91-97.]
[22]	Li XW, Li J (1993) A preliminary floristic study on the seed plants from the region of Hengduan Mountain. Acta Botanica Yunnanica, 15, 217-231. (in Chinese with English abstract)
	[李锡文, 李捷 (1993) 横断山脉地区种子植物区系的初步研究. 云南植物研究, 15, 217-231.]
[23]	Liao RL, Ma YP, Gong WC, Chen G, Sun WB, Zhou RC, Marczewski T (2015) Natural hybridization and asymmetric introgression at the distribution margin of two Buddleja species with a large overlap. BMC Plant Biology, 15, 146.
[24]	Ma YP, Xie WJ, Tian XL, Sun WB, Wu ZK, Milne R (2014) Unidirectional hybridization and reproductive barriers between two heterostylous primrose species in north-west Yunnan, China. Annals of Botany, 113, 763-775.
[25]	Mallet J (2005) Hybridization as an invasion of the genome. Trends in Ecology & Evolution, 20, 229-237.
[26]	Mao JF, Wang XR (2011) Distinct niche divergence characterizes the homoploid hybrid speciation of Pinus densata on the Tibetan Plateau. The American Naturalist, 177, 424-439.
[27]	Muranishi S, Tamaki I, Setsuko S, Tomaru N (2013) Asymmetric introgression between Magnolia stellata and M. salicifolia at a site where the two species grow sympatrically. Tree Genetics & Genomes, 9, 1005-1015.
[28]	Mutke J, Barthlott W (2005) Patterns of vascular plant diversity at continental to global scales. In: Plant Diversity and Complexity Patterns, Local, Regional and Global Dimensions (eds Friis I, Balslev H), pp. 521-537. The Royal Danish Academy of Sciences and Letters, Copenhagen, Biologiske Skrifter.
[29]	Myers N, Mittermeier RA, Mittermeier CG, da Fonseca GAB, Kent J (2000) Biodiversity hotspots for conservation priorities. Nature, 403, 853-858.
[30]	Natalis LC, Wesselingh RA (2012) Post-pollination barriers and their role in asymmetric hybridization in Rhinanthus (Orobanchaceae). American Journal of Botany, 99, 1847-1856.
[51]	Zhu XF, Li Y, Wu GL, Fang ZD, Li QJ, Liu JQ (2009) Molecular and morphological evidence for natural hybridization between Primula secundiflora Franchet and P. poissonii Franchet (Primulaceae). Acta Biologica Cracoviensia Series Botanica, 51, 29-36.
[31]	Noyes RD (2006) Intraspecific nuclear ribosomal DNA divergence and reticulation in sexual diploid Erigeron strigosus (Asteraceae). American Journal of Botany, 93, 470-479.