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Isolation and Characterization of Microsatellite Markers for the Chinese Endemic Species Rhododendron spinuliferum (Ericaceae)

中国特有种爆杖花的微卫星分子标记开发与评价



全 文 :中国特有种爆杖花的微卫星分子标记开发与评价∗
严丽君1ꎬ2ꎬ3ꎬ 张志荣2ꎬ 李德铢1ꎬ2ꎬ 高连明1∗∗
(1 中国科学院昆明植物研究所东亚植物多样性与生物地理学重点实验室ꎬ 云南 昆明  650201ꎻ 2 中国科学院
西南野生生物种质资源库ꎬ 云南 昆明  650201ꎻ 3 中国科学院大学ꎬ 北京  100049)
摘要: 爆杖花 (Rhododendron spinuliferum) 是中国西南地区特有的观赏和药用植物ꎮ 为了研究爆杖花和碎
米花之间的杂交物种形成过程ꎬ 本研究利用 FIASCO方法对爆杖花进行微卫星引物开发ꎬ 从 100对引物中
筛选出 28个微卫星标记ꎬ 其中 22个为多态ꎮ 利用爆杖花两个居群共 24个个体对 22个多态性位点进行分
析ꎬ 结果显示: 每个位点具有 2~5个等位基因ꎬ 平均为 3􀆰 4个ꎬ 其观测杂合度和期望杂合度分别为 0􀆰 083
~0􀆰 792和 0􀆰 153~0􀆰 744ꎮ 对筛出的 28个微卫星标记在碎米花的两个自然居群中也做了检测ꎬ 结果显示:
有 22个微卫星标记成功扩增ꎬ 其中 20个有多态性ꎻ 每个多态位点有 2~6个等位基因ꎬ 平均为 3􀆰 2个ꎬ 其
观测杂合度和期望杂合度分别为 0􀆰 000~0􀆰 833和 0􀆰 117~0􀆰 736ꎮ 开发的微卫星标记可用于爆杖花及其近缘
物种的居群遗传学分析和杂交物种形成研究ꎮ
关键词: 微卫星标记ꎻ 爆杖花ꎻ 碎米花ꎻ FIASCOꎻ 多态性
中图分类号: Q 943            文献标识码: A              文章编号: 2095-0845(2014)01-041-06
Isolation and Characterization of Microsatellite Markers
for the Chinese Endemic Species Rhododendron
spinuliferum (Ericaceae)
YAN Li ̄Jun1ꎬ2ꎬ3ꎬ ZHANG Zhi ̄Rong2ꎬ LI De ̄Zhu1ꎬ2ꎬ GAO Lian ̄Ming1∗
(1 Key Laboratory for Plant Diversity and Biogeography of East Asiaꎬ Kunming Institute of Botanyꎬ Chinese Academy of Sciencesꎬ
Kunming 650201ꎬ Chinaꎻ 2 Germplasm Bank of Wild Speciesꎬ Kunming Institute of Botanyꎬ Chinese Academy of Sciencesꎬ
Kunming 650201ꎬ Chinaꎻ 3 University of Chinese Academy of Sciencesꎬ Beijing 100049ꎬ China)
Abstract: Rhododendron spinuliferum (Ericaceae) is an ornamental and medicinal plant endemic to southwest Chi ̄
na. In order to study hybridization between R􀆰 spinuliferum and R􀆰 spiciferumꎬ a FIASCO (Fast Isolation by AFLP of
Sequences Containing Repeats) method was used to develop microsatellite markers in R􀆰 spinuliferum. A total of 28
microsatellite markers were isolated from 100 SSR primer pairsꎬ of which 22 were polymorphic. Polymorphism of the
22 polymorphic loci was assessed separately in 24 individuals collected from two wild populations. The number of al ̄
leles per locus ranged from 2 to 5ꎬ with an average of 3􀆰 4ꎬ while observed (HO) and expected (HE) heterozygosi ̄
ties varied from 0􀆰 083 to 0􀆰 792 and from 0􀆰 153 to 0􀆰 744ꎬ respectively. The same 28 microsatellite markers were al ̄
so tested in two wild populations (12 individuals from each) of R􀆰 spiciferum. Twenty two of the markers were suc ̄
cessfully amplifiedꎬ of which 20 were polymorphic. Estimates of diversity in two natural populations of R􀆰 spiciferum
based on the 20 polymorphic markers revealed that number of alleles per locus ranged from 2 to 6ꎬ with a mean of
3􀆰 2ꎬ while observed (HO ) and expected (HE ) heterozygosities ranged from 0􀆰 000 to 0􀆰 833 and from 0􀆰 117 to
植 物 分 类 与 资 源 学 报  2014ꎬ 36 (1): 41~46
Plant Diversity and Resources                                    DOI: 10.7677 / ynzwyj201413019

∗∗
Funding: The Key Program of the Chinese Academy of Sciences (KSCX2 ̄EW ̄Q ̄10ꎬ KSCX2 ̄EW ̄Z ̄2) and Key Research Program of the
Chinese Academy of Sciences (KJZD ̄EW ̄L07)
Author for correspondenceꎻ E ̄mail: gaolm@ mail. kib. ac. cn
Received date: 2013-02-20ꎬ Accepted date: 2013-04-11
作者简介: 严丽君 (1988-) 女ꎬ 博士研究生ꎬ 主要从事杜鹃花属系统发育与物种形成研究ꎮ E ̄mail: yanlijun@ mail. kib. ac. cn
0􀆰 736ꎬ respectively. These newly developed microsatellite markers will be used in future studies of hybridization and
the population genetics of R􀆰 spinuliferum and its closely related species.
Key words: Microsatellite markersꎻ Rhododendron spinuliferumꎻ Rhododendron spiciferumꎻ FIASCOꎻ Polymorphism
  Rhododendron L. is the largest genus in Ericace ̄
ae including about 1 025 speciesꎬ distributed from the
northern temperate zonesꎬ throughout tropical south ̄
eastern Asia to northeastern Australia (Chamberlain
et al.ꎬ 1996). There are 571 species in Chinaꎬ of
which 405 are endemic (Fang et al.ꎬ 2005). There is
a long horticultural history of Rhododendronꎬ and lots
of species in this genus have been used as ornamental
plants (Yang et al.ꎬ 1999). Rhododendron spinulife ̄
rum Franch. is one of the important ornamental spe ̄
ciesꎬ which is endemic to southwest China. The
dried stemsꎬ leaves and flowers of R􀆰 spinuliferum
can be used as Chinese folk medicine for eliminating
phlegmꎬ diminishing inflammationꎬ relieving cough
and asthma (Chen et al.ꎬ 1996).
Natural hybridization has been recognized as an
important factor of speciation and diversification
within Rhododendron (Milne et al.ꎬ 2010). Numer ̄
ous instances of natural hybridization have been re ̄
ported in Rhododendron in previous studies (Kron et
al.ꎬ 1993ꎻ Zhang et al.ꎬ 2007ꎻ Milne and Abbottꎬ
2008ꎻ Ma et al.ꎬ 2010ꎻ Zha et al.ꎬ 2010). Rhodo ̄
dendron × duclouxii is an inferred natural hybrid spe ̄
cies between R􀆰 spinuliferum and R􀆰 spiciferum
Franch. based on morphological characters (Handel ̄
Mazzettiꎬ 1936). This had been confirmed by mo ̄
lecular sequence data recently (Yan et al.ꎬ 2013).
To further study the extent of hybridization between
R􀆰 spinuliferum and R􀆰 spiciferumꎬ codominant micro ̄
satellite markers will be used. In this studyꎬ we tried
to isolate and characterize suitable microsatellite
markers from R􀆰 spinuliferumꎬ and test their feasibili ̄
ty in R􀆰 spiciferum samples.
1  Materials and methods
1􀆰 1  Materials
Leaf samples of R􀆰 spinuliferum used to develop
microsatellite markers were collected from two natu ̄
ral populations in Yunnan provinceꎬ China. Total of
24 individuals from two R􀆰 spinuliferum populations
(12 individuals from each) were selected to assess
polymorphisms of the developed microsatellite mark ̄
ers (Table 1). The feasibility of the developed mic ̄
rosatellite markers was also assessed in 24 individu ̄
als from two R􀆰 spiciferum natural populations ( 12
individuals from each) (Table 1). Voucher speci ̄
mens were deposited in the herbarium of the Kun ̄
ming Institute of Botanyꎬ Chinese Academy of Sci ̄
ences (KUN).
1􀆰 2  Methods
1􀆰 2􀆰 1  DNA extraction
Total genomic DNA was extracted from silica ̄gel ̄
dried leaves using an improved CTAB (cetyltrimethyl
ammonium bromide) method (Liu and Gaoꎬ 2011).
Table 1  Details of materials information used in this study
Taxon Locality Gepgraphic Altitude / m             Collection number
R􀆰 spinuliferum Kunmingꎬ Panlong areaꎬShuanglong town
N 25􀆰 10°
E 102􀆰 80° 2070
YLJ ̄12008ꎬ YLJ ̄12009ꎬ YLJ ̄120010ꎬ YLJ ̄12011ꎬ
YLJ ̄12012ꎬ YLJ ̄12013ꎬ YLJ ̄12014ꎬ YLJ ̄12015ꎬ
YLJ ̄12016ꎬ YLJ ̄12017ꎬ YLJ ̄12023ꎬ YLJ ̄12031
R􀆰 spinuliferum Chuxiongꎬ Shuangbaicountyꎬ Tuodian town
N 24􀆰 68°
E 101􀆰 66° 1775
YLJ ̄12802ꎬ YLJ ̄12803ꎬ YLJ ̄12804ꎬ YLJ ̄12805ꎬ
YLJ ̄12806ꎬ YLJ ̄12807ꎬ YLJ ̄12808ꎬ YLJ ̄12809ꎬ
YLJ ̄12810ꎬ YLJ ̄12811ꎬ YLJ ̄12813ꎬ YLJ ̄12817
R􀆰 spiciferum Kunmingꎬ Panlong areaꎬShuanglong town
N 25􀆰 10°
E 102􀆰 80° 2070
YLJ ̄12001ꎬ YLJ ̄12018ꎬ YLJ ̄12019ꎬ YLJ ̄12020ꎬ
YLJ ̄12025ꎬ YLJ ̄12027ꎬ YLJ ̄12029ꎬ YLJ ̄12030ꎬ
YLJ ̄12036ꎬ YLJ ̄12037ꎬ YLJ ̄12043ꎬ YLJ ̄12051
R􀆰 spiciferum Yuxiꎬ Eshan countyꎬGaoping town
N 24􀆰 22°
E 102􀆰 32° 1830
YLJ ̄121089ꎬ YLJ ̄121093ꎬ YLJ ̄121097ꎬ YLJ ̄121111ꎬ
YLJ ̄121120ꎬ YLJ ̄121122ꎬ YLJ ̄121123ꎬ YLJ ̄121124ꎬ
YLJ ̄121126ꎬ YLJ ̄121127ꎬ YLJ ̄121128ꎬ YLJ ̄121130
24                                  植 物 分 类 与 资 源 学 报                            第 36卷
1􀆰 2􀆰 2  Microsatellite loci isolationꎬ PCR amplifica ̄
tion and polymorphism assessment
The microsatellite loci were isolated based on
the FIASCO protocol ( Zane et al.ꎬ 2002). About
300- 500 ng genomic DNA was digested with MseI
(New England Biolabsꎬ Beverlyꎬ Massachusettsꎬ USA)ꎬ
and the digested DNA fragments were ligated to an
MseI AFLP adaptor pair ( 5′ ̄TACTCAGGACTCAT ̄
3′ / 5′ ̄GACGATGAGTCCTGAG ̄3′) at 37 ℃ for 2 h
with T4 DNA ligase (Fermentasꎬ Burlingtonꎬ Ontar ̄
ioꎬ Canada). Total of 5 μL of a diluted digestion ̄
ligation mixture (1 ∶ 10) was used for amplification
reactions with the adaptor ̄specific primers MseI ̄N
(5′ ̄GATGAGTCCTGAGTAAN ̄3′)ꎬ with the follow ̄
ing cycle program: 95 ℃ for 3 minꎬ 30 cycles of 94 ℃
for 45 sꎬ 50 ℃ for 60 sꎬ 72 ℃ for 60 sꎬ and a final
extension step of 7 min at 72 ℃ . The amplified frag ̄
ments (200-800 bp) were enriched for microsatel ̄
lite repeats by magnetic bead selection with 5′ ̄bioti ̄
nylated (AC) 15 and (AG) 15 . These enriched frag ̄
ments were amplified again with the MseI ̄N primers.
The PCR products were purified using an EZNA Gel
Extraction Kit (Omega Bio ̄Tekꎬ Guangzhouꎬ Chi ̄
na). The purified PCR products with enriched micro ̄
satellite repeats were ligated into the pGEM ̄T vector
(Promegaꎬ Madisonꎬ Wisconsinꎬ USA) and trans ̄
formed into DH5α cells (TaKaRaꎬ Dalianꎬ China).
Identification of recombinant clones was performed in
a blue / white selection assay. Positive clones were
then tested for microsatellite inserts by PCR with
(AC)10 / (AG)10 and T7 / Sp6 primersꎬ respectively.
Clones with positive inserts and appropriate size (300
-700 bp) were then sequenced. The sequences of
which contain microsatellite repeats ( SSRs)ꎬ and
with sufficient flanking regions were then used for de ̄
signing locus ̄specific primers with the program Oligo
6􀆰 0 (Offerman and Rychlikꎬ 2003).
The polymorphisms of all microsatellite loci
were then assessed in 24 individuals from two natural
populations (12 individuals from each) of R. spinu ̄
liferum (Table 1). PCR reactions were performed in
20 μL volumes containing 50-100 ng genomic DNAꎬ
0􀆰 6 μM of each primerꎬ 7􀆰 5 μL 2× Taq PCR Mas ̄
terMix (containing 0􀆰 1 U Taq polymerase / μLꎬ 0􀆰 5
mM dNTP eachꎬ 20 mM Tris ̄HCl (pH= 8􀆰 3)ꎬ 100
mM KClꎬ 3 mM MgCl2 (Tiangenꎬ Beijinꎬ China).
The PCR amplifications were conducted under the
following conditions: 95 ℃ for 3 min followed by 32
cycles at 94 ℃ for 30 sꎬ an annealing temperature op ̄
timized specifically for each primer pair (Table 2) for
45 sꎬ 72℃ for 60 sꎬ and a final extension step at 72℃
for 7 min. The amplified fragments were separated on
8% polyacrylamide denaturing gels with a 20 bp mo ̄
lecular size standard ladder (Fermentasꎬ Burlingtonꎬ
Ontarioꎬ Canada) and visualized by silver staining.
The polymorphic information content was calculated
by PIC Calculator. Standard genetic diversity param ̄
eters and deviations from the Hardy ̄Weinberg equi ̄
librium were estimated in GENEPOP version 4􀆰 0􀆰 10
(Roussetꎬ 2008) for all polymorphic loci. Estimation
for linkage disequilibrium between pairs of loci was
performed also in GENEPOP version 4􀆰 0􀆰 10.
2  Results and discussion
A total of 294 clones with positive inserts and
appropriate size were sequenced. Among these se ̄
quencesꎬ 217 ( 73􀆰 8%) sequences were found to
contain microsatellite repeats ( SSRs)ꎬ and 133 of
these sequences with sufficient flanking regions were
suitable for designing locus ̄specific primers. Final ̄
lyꎬ total of 100 primer sets were designed for develo ̄
ping microsatellite loci.
The evaluation criteria for the amplification suc ̄
cess rate of the loci followed Gao et al. (2012). Of
the 100 primer pairs testedꎬ 28 loci were successful ̄
ly amplifiedꎬ of which 22 showed polymorphismsꎬ
and six were monomorphic (Table 2). Sequences of
these primers were deposited in GenBank under the
accession numbers KC155596 to KC155623. For these
polymorphic primersꎬ the number of alleles per locus
(A) ranged from 2 to 5ꎬ with an average of 3􀆰 4ꎬ and
the values for the observed ( HO ) and expected
(HE) heterozygosities ranged from 0􀆰 083 to 0􀆰 792
and from 0􀆰 153 to 0􀆰 744ꎬ respectively. Five of the
341期      YAN Li ̄Jun et al.: Isolation and Characterization of Microsatellite Markers for the Chinese Endemic 􀆺     
22 polymorphic microsatellite loci deviated from Har ̄
dy ̄Weinberg equilibrium ( P < 0􀆰 01) ( Table 3)ꎬ
likely due to the presence of null alleles or few test ̄
ed samples included. There was no significant geno ̄
typic linkage disequilibrium (LD) between any pair
of loci at P<0􀆰 001.
Table 2  Characteristics of 28 microsatellite loci developed in R. spinuliferum
Locus Primer sequence (5′-3′) Repeat motif Size range / bp Ta / ℃
GenBank
accession No.
Polymorphic microsatellites
Rh003∗
F: TCTTCGTCTCCCTCTATCTTT
R: AACACACACAGACCTCAAATC
(TC)8 152-176 58 KC155596
Rh005∗
F: ATCATTGCTTCTTTTTCCCT
R: TCCACCCTCTGTCTCACTCT
(AG)12 164-182 55 KC155597
Rh008∗
F: TTGGAGTGAGAACAGAGAGG
R: TAATAGGCAGCATCTCCCAT
(AG)14 202-234 55 KC155598
Rh009∗
F: GGTAGCCACACTGTTGAAAT
R: CTTCCCCTCCATCTTGTTCT
(AG)8 216-230 54 KC155599
Rh017∗
F: TTTGGCTCATCGCTTTTAGT
R: GAGAGCATCCAAGTCCCTAT
(TC)10 151-175 54 KC155600
Rh020∗
F: GCATCTCAAGAACACAATA
R: TCAAGAAGGTCCTCCCAGTC
(AG)9 109-143 51 KC155601
Rh031∗
F: GAGGAGAGAAAAGGACAAG
R: AGTCTTCTTCCTTACCAACG
(AG)14 231-237 49 KC155603
Rh032∗
F: GGGCAAACATTCATACATAA
R: AGGCAGGCAGGCACCAGAAG
(TC)16 296-308 59 KC155604
Rh034∗
F: CAAAAAACACACCGCAGACG
R: TGATGGGTGGATGGATAAT
(AG)9 193-203 52 KC155605
Rh037
F: CCTGGGCAAGAGAGAAAACT
R: ACAGCGATGGCGATTTGAAC
(AG)8􀆺(AG)11 279-287 55 KC155606
Rh039∗
F: TCCTAATCCCTCCATCTCCC
R: GCCGTTCCATACAGTACCAA
(TC)10 156-168 57 KC155607
Rh041∗
F: CGATTGCCATTTGCCACTACCT
R: CCACAACTCCGCTGCTACTG
(TC)7 148-178 55 KC155608
Rh043∗
F: AGTTCCCCAAATCTCTTCTC
R: TCATTTTCTTTTCTCTGCCT
(AG)23 149-175 53 KC155610
Rh054
F: TGTAGCAAACCCATCTCACC
R: TCACCTGGGCATAACTAATC
(TC)8 261-275 58 KC155611
Rh058∗
F: GATATGGACTCCGACAAGGT
R: GGCGAGATCGTGGAGAAAAT
(TC)9 174-180 58 KC155612
Rh060∗
F: AAGAGATTGGAAGGGTTGAT
R: TCATAGTGTGGCAAAACGAC
(AG)7􀆺(AG)7 166-172 54 KC155613
Rh063
F: TGACGACATGGGACTTTAGA
R: ACCCTTTCTTCATCTTCCAG
(TC)20 164-172 52 KC155614
Rh065
F: TAAAAAAATGGGGCTAAAGT
R: GACATTGACGCAGCCGAACC
(AG)16 261-283 50 KC155616
Rh072∗
F: GCTCTACCCTTATCATTTTA
R: AAGACGGACGAAACACATC
(TC)25 169-181 57 KC155617
Rh076∗
F: ATACACCACCATTCATACGC
R: TAGAGAGTGGGGTTGATTAG
(AG)17G(AG)6􀆺(AG)8 258-310 20 KC155618
Rh078∗
F: CAATGATGTGAAAGCCCTGG
R: AGGATTCCAATTAGTAAACG
(TG)8 284-300 50 KC155619
44                                  植 物 分 类 与 资 源 学 报                            第 36卷
Table 2 continued
Locus Primer sequence (5′-3′) Repeat motif Size range / bp Ta / ℃
GenBank
accession No.
Rh086∗
F: ATCACCCAAGCAATAGTCTG
R: ATTTTCCACACGATACAGGC
(TC) 9􀆺 (TG) 8 269-281 57 KC155620
Monomorphic microsatellites
Rh023∗
F: CTACCATCAACATCACACTG
R: AGTAAAAAGAGAAGGGGAGT
(TC)8 131 52 KC155602
Rh042∗
F: CACAAGTGTTCCAAGATTCG
R: GACGGGAGTTATCGGTGAAG
(TC)7C(TC)9 165 55 KC155609
Rh064∗
F: GATGGTAGTTTCAACGCAAG
R: ACTCCTTTCTTTTCTCACCT
(AG)9 193 52 KC155615
Rh087
F: AGAATAGAAGGTTGAAGGGT
R: AAGGCTTGAATGAGGTTGAT
(TC)13 217 52 KC155621
Rh096∗
F: CCCTCCTCTCTCAACAAAAG
R: TCAGAGTTGTTCGGTGTGTG
(TC)10 157 54 KC155622
Rh098
F: AAACCCCATTACAGTAGATT
R: ACTGGACCCTTGAAACCTAAC
(AG)9 189 50 KC155623
Note: Taꎬ PCR annealing temperatureꎻ ∗ꎬ successful amplification in R􀆰 spiciferum
Table 3  Results of the polymorphic microsatellite loci evaluated in two wild populations (12 individuals from each)
of R􀆰 spinuliferum and R􀆰 spicifeum respectively
Locus
R􀆰 spinuliferum
NA HO HE PHW
R􀆰 spicifeum
NA HO HE PHW
Rh003 4􀆰 000 0􀆰 739 0􀆰 616 0􀆰 113 3􀆰 000 0􀆰 833 0􀆰 542 0􀆰 005∗
Rh005 4􀆰 000 0􀆰 375 0􀆰 318 1􀆰 000 2􀆰 000 0􀆰 250 0􀆰 278 0􀆰 502
Rh008 4􀆰 000 0􀆰 417 0􀆰 357 1􀆰 000 4􀆰 000 0􀆰 667 0􀆰 587 0􀆰 142
Rh009 2􀆰 000 0􀆰 083 0􀆰 153 0􀆰 128 2􀆰 000 0􀆰 545 0􀆰 496 1􀆰 000
Rh017 5􀆰 000 0􀆰 750 0􀆰 724 0􀆰 254 2􀆰 000 0􀆰 500 0􀆰 469 1􀆰 000
Rh020 4􀆰 000 0􀆰 792 0􀆰 744 0􀆰 090 2􀆰 000 0􀆰 542 0􀆰 430 0􀆰 355
Rh023 2􀆰 000 0􀆰 042 0􀆰 117 0􀆰 063
Rh031 4􀆰 000 0􀆰 333 0􀆰 510 0􀆰 011 4􀆰 000 0􀆰 500 0􀆰 688 0􀆰 148
Rh032 3􀆰 000 0􀆰 565 0􀆰 638 0􀆰 336 4􀆰 000 0􀆰 333 0􀆰 641 0􀆰 001∗
Rh034 3􀆰 000 0􀆰 250 0􀆰 227 1􀆰 000 4􀆰 000 0􀆰 708 0􀆰 736 0􀆰 023
Rh037 4􀆰 000 0􀆰 227 0􀆰 714 0􀆰 000∗
Rh039 4􀆰 000 0􀆰 667 0􀆰 643 0􀆰 565 3􀆰 000 0􀆰 542 0􀆰 594 0􀆰 477
Rh041 4􀆰 000 0􀆰 583 0􀆰 513 1􀆰 000 3􀆰 000 0􀆰 500 0􀆰 492 0􀆰 301
Rh043 2􀆰 000 0􀆰 458 0􀆰 430 1􀆰 000 3􀆰 000 0􀆰 250 0􀆰 624 0􀆰 000∗
Rh054 2􀆰 000 0􀆰 174 0􀆰 476 0􀆰 002∗
Rh058 4􀆰 000 0􀆰 417 0􀆰 506 0􀆰 091 4􀆰 000 0􀆰 792 0􀆰 711 0􀆰 104
Rh060 3􀆰 000 0􀆰 250 0􀆰 473 0􀆰 001∗ 3􀆰 000 0􀆰 333 0􀆰 645 0􀆰 008∗
Rh063 3􀆰 000 0􀆰 625 0􀆰 555 1􀆰 000
Rh065 3􀆰 000 0􀆰 708 0􀆰 661 0􀆰 670
Rh072 3􀆰 000 0􀆰 208 0􀆰 659 0􀆰 000∗ 5􀆰 000 0􀆰 708 0􀆰 728 0􀆰 523
Rh076 4􀆰 000 0􀆰 375 0􀆰 704 0􀆰 000∗ 6􀆰 000 0􀆰 333 0􀆰 538 0􀆰 016
Rh078 3􀆰 000 0􀆰 333 0􀆰 351 0􀆰 157 3􀆰 000 0􀆰 333 0􀆰 586 0􀆰 015
Rh086 3􀆰 000 0􀆰 208 0􀆰 320 0􀆰 056 2􀆰 000 0􀆰 000 0􀆰 287 0􀆰 000∗
Rh096 2􀆰 000 0􀆰 208 0􀆰 492 0􀆰 006∗
Note: NAꎬ number of alleles revealedꎻ HOꎬ observed heterozygosityꎻ HEꎬ expected heterozygosityꎻ ∗ꎬ polymorphic microsatellite loci deviating
from Hardy ̄Weinberg equilibrium (P<0􀆰 01) .
541期      YAN Li ̄Jun et al.: Isolation and Characterization of Microsatellite Markers for the Chinese Endemic 􀆺     
    The 28 microsatellite markers were also tested
in R􀆰 spiciferum using the same PCR conditions as in
R􀆰 spinuliferum. Of the 28 loci testedꎬ 22 SSR mark ̄
ers were amplified successfullyꎬ of which 20 loci
showed polymorphisms and two loci were monomor ̄
phic (Rh042 and Rh064) in R􀆰 spiciferum (Table 2
& 3). The two monomorphic microsatellite markers
(Rh023 and Rh096) in R􀆰 spinuliferum showed pol ̄
ymorphism in R􀆰 spiciferum (Table 2 & 3). For the
20 polymorphic markers of R􀆰 spiciferumꎬ the number
of alleles per locus ranged from 2 to 6ꎬ with a mean
of 3􀆰 2. The observed (HO) and expected (HE) het ̄
erozygosity ranged from 0􀆰 000 to 0􀆰 833 and from
0􀆰 117 to 0􀆰 736ꎬ respectively. Six of the 20 polymor ̄
phic microsatellite loci deviated from the Hardy ̄
Weinberg equilibrium (P<0􀆰 01) (Table 3).
In summaryꎬ of the 28 microsatellite markers
firstly developed in R􀆰 spinuliferumꎬ most worked in
R􀆰 spiciferum (79%). Thusꎬ these codominant mic ̄
rosatellite markers developed in this study will be
very useful to investigate the hybrid speciation sce ̄
nario between R􀆰 spinuliferum and R􀆰 spiciferumꎬ and
also be useful to assess the genetic diversity and
population structure of R􀆰 spinuliferum and other
closely related species.
Acknowledgements: We are grateful to JB Yangꎬ J Yangꎬ
HT Liꎬ WB Yuan and CY Lin for their help in lab work and
data analysis. We also thank Michael Möller from Royal Bo ̄
tanic Garden Edinburgh for improving English of the MS. La ̄
boratory work was performed at the Laboratory of Molecular
Biology at the Germplasm Bank of Wild Speciesꎬ Kunming
Institute of Botanyꎬ Chinese Academy of Sciences.
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64                                  植 物 分 类 与 资 源 学 报                            第 36卷