Effects of environmental and genetic factors on phenotypic traits and species classification of Dendrobium huoshanense

doi:10.17520/biods.2021001

Abstract

Abstract:

Aims: Dendrobium is one of the largest genera in Orchidaceae. The species of this genus are characterized by high morphological diversity. Dendrobium huoshanense is an endemic species of China with high pharmaceutical and conservation value. However, the boundary of the species is still in debate. In this study, we aim to explore the variations of phenotypic traits affected by environmental and genetic factors, and define the boundaries among D. huoshanense and its related species.

Methods: We measured 12 phenotypic traits from 2,279 specimens in 16 populations from the dendrobiums planting base in Huoshan County, Anhui Province, East China, including wild and F₁, F₂ generation of D. huoshanense, wild D. henanense, D. moniliforme and D. catenatum. The F₁ and F₂ generations of D. huoshanense were cultivated from the seeds of random hand-pollination flowers in wild population and F₁ generation population from this base, respectively. We first used common-garden experiment method and intergenerational comparison to estimate the phenotypic variations of D. huoshanense affected by environmental and genetic factors. Furthermore, the phenotypic variations of D. huoshanense and its related species were estimated by statistical analysis.

Results: The results showed that F₁ and F₂ generations of D. huoshanense in greenhouse and woodland conditions had larger and longer pseudobulbs than that of wild specimens under the common-garden experiment method. With the intergenerational comparison, we found that the pseudobulb diameters of F₁ generation were wider than that of F₂ generation. Among related species, we found that the pseudobulb lengths and diameters as well as the petals of D. huoshanense were significantly different from that of D. catenatum and D. moniliforme. At the same time, D. huoshanense only showed significant differences in morphological traits of pseudobulbs with that of D. henanense.

Conclusion: Our results suggest that both environmental and genetic factors have significant effects on phenotypic changes of D. huoshanense and affect the delineation of species boundaries among D. huoshanense and its related species.

Key words: Dendrobium, Orchidaceae, phenotypic traits, environmental factors, genetic factors

Zhenbin Jiao, Yibo Luo. Effects of environmental and genetic factors on phenotypic traits and species classification of Dendrobium huoshanense[J]. Biodiv Sci, 2021, 29(8): 1073-1086.

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URL: https://www.biodiversity-science.net/EN/10.17520/biods.2021001

https://www.biodiversity-science.net/EN/Y2021/V29/I8/1073

Figures/Tables 5

References 64

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	野生型 Wild type	F₁代 F₁ generation		F₂代 F₂ generation
	野生型 Wild type	林间 Woodland	温室 Greenhouse	林间 Woodland	温室 Greenhouse
假鳞茎数量 Number of pseudobulbs	93	202	355	221	500
假鳞茎茎长 Pseudobulb length (cm)	1.84 ± 0.85^A	5.53 ± 2.59^BE	5.80 ± 2.65^BCE	4.92 ± 2.28^BD	5.77 ± 2.83^BCE
假鳞茎直径 Pseudobulb diameter (cm)	0.45 ± 0.07^A	0.70 ± 0.12^B	0.69 ± 0.13^B	0.58 ± 0.13^C	0.59 ± 0.13^C
假鳞茎茎长直径比 Length/diameter ratio of pseudobulb	4.17 ± 2.03^A	7.98 ± 3.70^B	8.64 ± 4.24^B	9.13 ± 5.07^BC	10.16 ± 5.55^C
假鳞茎节长 Internode length of pseudobulb (cm)	0.65 ± 0.18^A	1.14 ± 0.32^BE	1.26 ± 0.36^CE	1.18 ± 0.30^BcDE	1.20 ± 0.39^BCDE
假鳞茎节数 Number of pseudobulb internodes	3.67 ± 0.81^A	6.02 ± 1.46^BE	5.75 ± 1.28^Bce	5.48 ± 1.40^C	6.05 ± 1.62^BDE
花朵数量 Number of flowers	2	26	107	31	151
中萼片长 Dorsal sepal length (cm)	1.35 ± 0.07^A	1.41 ± 0.16^AB	1.29 ± 0.19^AC	1.51 ± 0.26^ABD	1.44 ± 0.23^ABD
中萼片宽 Dorsal sepal width (cm)	0.60 ± 0^AE	0.68 ± 0.09^Be	0.66 ± 0.11^BC	0.66 ± 0.10^aBCDE	0.61 ± 0.09^AbDE
中萼片长宽比 Length/width ratio of dorsal sepal	2.25 ± 0.11^A	2.11 ± 0.34^AB	2.02 ± 0.34^ABC	2.29 ± 0.38^ABD	2.39 ± 0.44^AD
花瓣长 Petal length (cm)	1.40 ± 0^A	1.37 ± 0.15^AB	1.28 ± 0.21^BC	1.47 ± 0.24^ABD	1.42 ± 0.22^ABD
花瓣宽 Petal width (cm)	0.80 ± 0^A	0.80 ± 0.11^A	0.77 ± 0.14^A	0.76 ± 0.13^AD	0.68 ± 0.13^d
花瓣长宽比 Length/width ratio of petal	1.75 ± 0^A	1.74 ± 0.28^AB	1.71 ± 0.30^ABC	1.99 ± 0.41^aBcD	2.13 ± 0.39^D
花梗长 Pedicel length (cm)	2.15 ± 0.07^A	1.93 ± 0.46^A	2.11 ± 0.44^A	2.07 ± 0.43^A	2.17 ± 0.51^A

	野生型 Wild type	F₁代 F₁ generation		F₂代 F₂ generation
	野生型 Wild type	林间 Woodland	温室 Greenhouse	林间 Woodland	温室 Greenhouse
假鳞茎数量 Number of pseudobulbs	93	202	355	221	500
假鳞茎茎长 Pseudobulb length (cm)	1.84 ± 0.85^A	5.53 ± 2.59^BE	5.80 ± 2.65^BCE	4.92 ± 2.28^BD	5.77 ± 2.83^BCE
假鳞茎直径 Pseudobulb diameter (cm)	0.45 ± 0.07^A	0.70 ± 0.12^B	0.69 ± 0.13^B	0.58 ± 0.13^C	0.59 ± 0.13^C
假鳞茎茎长直径比 Length/diameter ratio of pseudobulb	4.17 ± 2.03^A	7.98 ± 3.70^B	8.64 ± 4.24^B	9.13 ± 5.07^BC	10.16 ± 5.55^C
假鳞茎节长 Internode length of pseudobulb (cm)	0.65 ± 0.18^A	1.14 ± 0.32^BE	1.26 ± 0.36^CE	1.18 ± 0.30^BcDE	1.20 ± 0.39^BCDE
假鳞茎节数 Number of pseudobulb internodes	3.67 ± 0.81^A	6.02 ± 1.46^BE	5.75 ± 1.28^Bce	5.48 ± 1.40^C	6.05 ± 1.62^BDE
花朵数量 Number of flowers	2	26	107	31	151
中萼片长 Dorsal sepal length (cm)	1.35 ± 0.07^A	1.41 ± 0.16^AB	1.29 ± 0.19^AC	1.51 ± 0.26^ABD	1.44 ± 0.23^ABD
中萼片宽 Dorsal sepal width (cm)	0.60 ± 0^AE	0.68 ± 0.09^Be	0.66 ± 0.11^BC	0.66 ± 0.10^aBCDE	0.61 ± 0.09^AbDE
中萼片长宽比 Length/width ratio of dorsal sepal	2.25 ± 0.11^A	2.11 ± 0.34^AB	2.02 ± 0.34^ABC	2.29 ± 0.38^ABD	2.39 ± 0.44^AD
花瓣长 Petal length (cm)	1.40 ± 0^A	1.37 ± 0.15^AB	1.28 ± 0.21^BC	1.47 ± 0.24^ABD	1.42 ± 0.22^ABD
花瓣宽 Petal width (cm)	0.80 ± 0^A	0.80 ± 0.11^A	0.77 ± 0.14^A	0.76 ± 0.13^AD	0.68 ± 0.13^d
花瓣长宽比 Length/width ratio of petal	1.75 ± 0^A	1.74 ± 0.28^AB	1.71 ± 0.30^ABC	1.99 ± 0.41^aBcD	2.13 ± 0.39^D
花梗长 Pedicel length (cm)	2.15 ± 0.07^A	1.93 ± 0.46^A	2.11 ± 0.44^A	2.07 ± 0.43^A	2.17 ± 0.51^A

	霍山石斛 D. huoshanense			河南石斛 D. henanense	细茎石斛 D. moniliforme	铁皮石斛 D. catenatum
	Wild type	F₁ generation	F₂ generation	河南石斛 D. henanense	细茎石斛 D. moniliforme	铁皮石斛 D. catenatum
假鳞茎数量 No. of pseudobulbs	93	557	721	98	217	414
假鳞茎茎长 Pseudobulb length (cm)	1.84 ± 0.85^A	5.70 ± 2.63^B	5.51 ± 2.70^B	8.76 ± 2.12^C	18.54 ± 5.87^E	14.97 ± 8.26^D
假鳞茎直径 Pseudobulb diameter (cm)	0.45 ± 0.07^A	0.70 ± 0.13^B	0.59 ± 0.13^C	0.43 ± 0.06^AD	0.39 ± 0.09^F	0.53 ± 0.11^E
假鳞茎茎长直径比 Length/diameter ratio of pseudobulb	4.17 ± 2.03^A	8.40 ± 4.06^B	9.84 ± 5.42^C	20.75 ± 5.90^D	48.99 ± 16.88^F	30.16 ± 19.40^E
假鳞茎节长 Internode length of pseudobulb (cm)	0.65 ± 0.18^A	1.21 ± 0.35^B	1.19 ± 0.36^B	1.52 ± 0.32^C	2.38 ± 0.55^D	1.65 ± 0.57^c
假鳞茎节数 No. of pseudobulb internodes	3.67 ± 0.81^A	5.85 ± 1.35^B	5.87 ± 1.58^B	8.45 ± 1.44^C	10.42 ± 2.30^d	11.17 ± 3.21^D
花朵数量 Number of flowers	2	132	181	5	138	235
中萼片长 Dorsal sepal length (cm)	1.35 ± 0.07^A	1.32 ± 0.19^AB	1.45 ± 0.23^AC	1.62 ± 0.15^ABCD	1.47 ± 0.27^ACD	1.77 ± 0.23^ADE
中萼片宽 Dorsal sepal width (cm)	0.60 ± 0^A	0.66 ± 0.11^B	0.62 ± 0.09^abC	0.70 ± 0.09^ABCD	0.51 ± 0.08^DF	0.63 ± 0.07^bCDE
中萼片长宽比 Length/width ratio of dorsal sepal	2.25 ± 0.11^A	2.03 ± 0.34^AB	2.37 ± 0.43^AC	2.35 ± 0.31^ABCD	2.90 ± 0.45^ADE	2.83 ± 0.40^ADE
花瓣长 Petal length (cm)	1.40 ± 0^A	1.30 ± 0.20^B	1.43 ± 0.22^ACF	1.52 ± 0.07^AbCDF	1.49 ± 0.24^DF	1.67 ± 0.20^DE
花瓣宽 Petal width (cm)	0.80 ± 0^A	0.77 ± 0.14^AB	0.69 ± 0.13^C	0.82 ± 0.04^ABcD	0.52 ± 0.09^F	0.56 ± 0.07^E
花瓣长宽比 Length/width ratio of petal	1.75 ± 0^A	1.72 ± 0.29^AB	2.11 ± 0.40^C	1.86 ± 0.16^ABCD	2.92 ± 0.47^E	3.01 ± 0.46^E

	霍山石斛 D. huoshanense			河南石斛 D. henanense	细茎石斛 D. moniliforme	铁皮石斛 D. catenatum
	Wild type	F₁ generation	F₂ generation	河南石斛 D. henanense	细茎石斛 D. moniliforme	铁皮石斛 D. catenatum
假鳞茎数量 No. of pseudobulbs	93	557	721	98	217	414
假鳞茎茎长 Pseudobulb length (cm)	1.84 ± 0.85^A	5.70 ± 2.63^B	5.51 ± 2.70^B	8.76 ± 2.12^C	18.54 ± 5.87^E	14.97 ± 8.26^D
假鳞茎直径 Pseudobulb diameter (cm)	0.45 ± 0.07^A	0.70 ± 0.13^B	0.59 ± 0.13^C	0.43 ± 0.06^AD	0.39 ± 0.09^F	0.53 ± 0.11^E
假鳞茎茎长直径比 Length/diameter ratio of pseudobulb	4.17 ± 2.03^A	8.40 ± 4.06^B	9.84 ± 5.42^C	20.75 ± 5.90^D	48.99 ± 16.88^F	30.16 ± 19.40^E
假鳞茎节长 Internode length of pseudobulb (cm)	0.65 ± 0.18^A	1.21 ± 0.35^B	1.19 ± 0.36^B	1.52 ± 0.32^C	2.38 ± 0.55^D	1.65 ± 0.57^c
假鳞茎节数 No. of pseudobulb internodes	3.67 ± 0.81^A	5.85 ± 1.35^B	5.87 ± 1.58^B	8.45 ± 1.44^C	10.42 ± 2.30^d	11.17 ± 3.21^D
花朵数量 Number of flowers	2	132	181	5	138	235
中萼片长 Dorsal sepal length (cm)	1.35 ± 0.07^A	1.32 ± 0.19^AB	1.45 ± 0.23^AC	1.62 ± 0.15^ABCD	1.47 ± 0.27^ACD	1.77 ± 0.23^ADE
中萼片宽 Dorsal sepal width (cm)	0.60 ± 0^A	0.66 ± 0.11^B	0.62 ± 0.09^abC	0.70 ± 0.09^ABCD	0.51 ± 0.08^DF	0.63 ± 0.07^bCDE
中萼片长宽比 Length/width ratio of dorsal sepal	2.25 ± 0.11^A	2.03 ± 0.34^AB	2.37 ± 0.43^AC	2.35 ± 0.31^ABCD	2.90 ± 0.45^ADE	2.83 ± 0.40^ADE
花瓣长 Petal length (cm)	1.40 ± 0^A	1.30 ± 0.20^B	1.43 ± 0.22^ACF	1.52 ± 0.07^AbCDF	1.49 ± 0.24^DF	1.67 ± 0.20^DE
花瓣宽 Petal width (cm)	0.80 ± 0^A	0.77 ± 0.14^AB	0.69 ± 0.13^C	0.82 ± 0.04^ABcD	0.52 ± 0.09^F	0.56 ± 0.07^E
花瓣长宽比 Length/width ratio of petal	1.75 ± 0^A	1.72 ± 0.29^AB	2.11 ± 0.40^C	1.86 ± 0.16^ABCD	2.92 ± 0.47^E	3.01 ± 0.46^E