Molecular and morphological evidence for natural hybridization between Rhododendron decorum and R. delavayi (Ericaceae)

doi:10.17520/biods.2017090

Abstract

Abstract:

The southwestern region of China is the center of differentiation for the genus Rhododendron. Studies on the natural hybridization of Rhododendron provide solutions for taxonomic problems and enhance the ability to breed new cultivars faster. In this paper, we compared the morphological features and sequenced nuclear internal transcribed spacer (ITS) and chloroplast trnL-trnF, rbcL, trnH-psbA for Rhododendron decorum, R. delavayi, and the putative hybrid offspring of these two species. All samples in this study were collected from Baili Rhododendron Nature Reserve in Guizhou Province, the Shibao Mountain of Yunnan Province and Kunming Botanical Garden. Results showed that all putative hybrids (natural and artificial) produced an intermediate morphology. Sequencing results revealed that all artificial hybrids and one collected from the Shibao Mountain inherited cpDNA from R. decorum, and all putative hybrids collected from Baili Rhododendron Nature Reserve and six from Shibao Mountain inherited cpDNA from R. delavayi. In this study, we have confirmed that natural hybridization between R. decorum and R. delavayi exists in the Guizhou and Yunnan sites. Hybridization was bilateral, and most of the hybrids were derived from maternal parent R. delavayi.

http://jtp.cnki.net/bilingual/detail/html/SWDY201706008

Key words: Rhododendron, natural hybridization, morphological traits, DNA sequences

Shuoli Zheng, Xiaoling Tian, Chengling Huang, Lingjun Wang, Yuan Feng, Jingli Zhang. Molecular and morphological evidence for natural hybridization between Rhododendron decorum and R. delavayi (Ericaceae)[J]. Biodiv Sci, 2017, 25(6): 627-637.

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URL: https://www.biodiversity-science.net/EN/10.17520/biods.2017090

https://www.biodiversity-science.net/EN/Y2017/V25/I6/627

Figures/Tables 9

References 45

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编号 Code	种类 Taxon	地点 Site	经纬度 Latitude and longitude	海拔 Altitude (m)	个体数量 Sample size
BLM (1-10)	马缨杜鹃 R. delavayi	贵州百里杜鹃自然保护区 Baili Rhododendron Nature Reserve in Guizhou Province	27°15′ N 105°58′ E	1,700-1,800	10
BLD (1-10)	大白杜鹃 R. decorum	贵州百里杜鹃自然保护区 Baili Rhododendron Nature Reserve in Guizhou Province	27°15′ N 105°58′ E	1,700-1,800	10
BLH (1-8)	疑似杂交后代 Putative hybrids	贵州百里杜鹃自然保护区 Baili Rhododendron Nature Reserve in Guizhou Province	27°15′ N 105°58′ E	1,700-1,800	8
SBSM (1-5)	马缨杜鹃 R. delavayi	云南大理石宝山 Shibao Mountain of Dali, Yunnan	26°22′ N 99°50′ E	2,400-2,600	5
SBSD (1-5)	大白杜鹃 R. decorum	云南大理石宝山 Shibao Mountain of Dali, Yunnan	26°22′ N 99°50′ E	2,400-2,600	5
SBSH (2/3/4/5/7/8/9)	疑似杂交后代 Putative hybrids	云南大理石宝山 Shibao Mountain of Dali, Yunnan	26°22′ N 99°50′ E	2,400-2,600	7
AH (1-5)	人工杂交后代 Artificial hybrids	昆明植物园 Kunming Botanical Garden			5
总计 Total					50

编号 Code	种类 Taxon	地点 Site	经纬度 Latitude and longitude	海拔 Altitude (m)	个体数量 Sample size
BLM (1-10)	马缨杜鹃 R. delavayi	贵州百里杜鹃自然保护区 Baili Rhododendron Nature Reserve in Guizhou Province	27°15′ N 105°58′ E	1,700-1,800	10
BLD (1-10)	大白杜鹃 R. decorum	贵州百里杜鹃自然保护区 Baili Rhododendron Nature Reserve in Guizhou Province	27°15′ N 105°58′ E	1,700-1,800	10
BLH (1-8)	疑似杂交后代 Putative hybrids	贵州百里杜鹃自然保护区 Baili Rhododendron Nature Reserve in Guizhou Province	27°15′ N 105°58′ E	1,700-1,800	8
SBSM (1-5)	马缨杜鹃 R. delavayi	云南大理石宝山 Shibao Mountain of Dali, Yunnan	26°22′ N 99°50′ E	2,400-2,600	5
SBSD (1-5)	大白杜鹃 R. decorum	云南大理石宝山 Shibao Mountain of Dali, Yunnan	26°22′ N 99°50′ E	2,400-2,600	5
SBSH (2/3/4/5/7/8/9)	疑似杂交后代 Putative hybrids	云南大理石宝山 Shibao Mountain of Dali, Yunnan	26°22′ N 99°50′ E	2,400-2,600	7
AH (1-5)	人工杂交后代 Artificial hybrids	昆明植物园 Kunming Botanical Garden			5
总计 Total					50

形态特征 Morphological characters	大白杜鹃 R. decorum	疑似自然杂交与人工杂交后代 Putative and artificial hybrids	马缨杜鹃 R. delavayi
花冠颜色 Corolla color	白色 White	粉红 Pink	红色 Red
花冠裂片数 No. of corolla lobes	6-8, 通常7 6-8, usually 7	5-6, 无规律 5-6, irregular	5
叶片形状 Leaf shape	长圆形 Oblong	长圆形至披针形 Oblong to lanceolate	披针形 Lanceolate
叶片毛被 Ventral leaf suraface indumentum	无毛 Glabrous	稀疏毛被 Thin indumentum	浓密海绵状毛被 Woolly indumentum
果实表面特征 Fruit surface character	有腺体 Glands	有腺体或毛被或两者均有 Glands or/and indumentum	密被棕红色毛被 Continuous brownish red indumentum
花期 Flowering period	5-6月 May to June	4月中旬-5月中旬 Mid-April to mid-May	3月-5月 March to May

形态特征 Morphological characters	大白杜鹃 R. decorum	疑似自然杂交与人工杂交后代 Putative and artificial hybrids	马缨杜鹃 R. delavayi
花冠颜色 Corolla color	白色 White	粉红 Pink	红色 Red
花冠裂片数 No. of corolla lobes	6-8, 通常7 6-8, usually 7	5-6, 无规律 5-6, irregular	5
叶片形状 Leaf shape	长圆形 Oblong	长圆形至披针形 Oblong to lanceolate	披针形 Lanceolate
叶片毛被 Ventral leaf suraface indumentum	无毛 Glabrous	稀疏毛被 Thin indumentum	浓密海绵状毛被 Woolly indumentum
果实表面特征 Fruit surface character	有腺体 Glands	有腺体或毛被或两者均有 Glands or/and indumentum	密被棕红色毛被 Continuous brownish red indumentum
花期 Flowering period	5-6月 May to June	4月中旬-5月中旬 Mid-April to mid-May	3月-5月 March to May

编号 Code	克隆数量 Clone numbers	类型 Type	差异位点 Variable sites (bp)						类型 Type
编号 Code	克隆数量 Clone numbers	类型 Type	94	101	114	203	494	505	A1	A2	A4
大白杜鹃 R. decorum	0	A1	T	G	G	T	T	C	15	0	0
马缨杜鹃 R. delavayi	0	A2	C	C	T	G	C	T	0	15	0
AH、BLH、SBSH		A3	Y	S	K	K	Y	Y
克隆测序 Clone sequences
BLH1	2								1	1	0
BLH2	4								1	2	1
BLH3	3								2	1	0
BLH4	3								2	1	0
BLH5	3								1	1	1
BLH6	5								1	1	3
BLH7	4								2	1	1
BLH8	4								2	1	1
AH1	3								1	2	1
AH2	3								1	2	0
AH3	4								2	2	0
AH4	3								2	1	0
AH5	4								2	2	1
SBSH2	6								4	2	0
SBSH3	8								5	3	0
SBSH4	5								4	1	0
SBSH5	5								4	1	0
SBSH7	7								5	2	0
SBSH8	7								6	1	0
SBSH9	5								3	2	0
克隆数量总计 Total clone numbers									53	31	10