宽皮柑橘果实的剥皮性及与细胞壁多糖的关系

doi:10.16420/j.issn.0513-353x.2020-0973

摘要/Abstract

摘要：

以‘向山’（Citrus reticulata Blanco‘Mukaiyama’）、‘克里曼丁’（C. clementina hort.ex. Tanaka）、‘弗莱蒙特’（C. reticulata Blanco‘Fremont’）和‘药香柑’（C. reticulata Blanco‘Yaoxianggan’）4种宽皮柑橘为试材,比较分析了果实成熟过程不同时期的剥皮性、果皮形态、细胞壁多糖含量、细胞壁多糖降解相关酶活性及部分基因表达的变化。在果实成熟过程中,反映剥皮性的两个力学指标（果皮粘力和硬度）均显著下降。不同材料的剥皮性有所差异,‘药香柑’与‘弗莱蒙特’的果皮粘力较高,‘克里曼丁’和‘向山’较低;‘药香柑’的果皮硬度最高,‘弗莱蒙特’次之,‘克里曼丁’和‘向山’最低。相关性分析表明果皮粘力和硬度呈显著正相关,且易剥皮性状与低水平的细胞壁多糖物质和高水平的细胞壁多糖降解相关酶活性密切相关。在果实成熟过程中,4种柑橘果皮中的多种细胞壁多糖组分的含量均有不同程度的下降,参与细胞壁降解的酶活性及部分编码基因表达水平随之上升,另有部分编码木聚糖酶抑制蛋白和果胶甲酯酶抑制蛋白的基因下调表达。易剥皮的‘向山’和‘克里曼丁’果皮中的总细胞壁干物质和部分细胞壁多糖组分（半纤维素、纤维素、原果胶）的含量低于难剥皮的‘药香柑’和‘弗莱蒙特’,这可能与木聚糖酶、纤维素酶和多种果胶降解相关酶的活性水平较高有关。

关键词: 柑橘, 剥皮性, 硬度, 粘力, 细胞壁多糖, 酶活性, 基因表达

Abstract:

To clarify the relationship between the ease of peeling of mandarins and cell wall polysaccharides,which are thought to support the plant cell integration,adherence and mechanical strength,the ease of peeling,peel morphology,cell wall polysaccharide contents,the activities of the enzymes related to cell wall polysaccharide degradation and the expression level of some related genes were analyzed in four mandarin varieties,Citrus reticulata Blanco‘Mukaiyama’,C. clementina hort. ex. Tanaka,C. reticulata Blanco‘Fremont’and C. reticulata Blanco‘Yaoxianggan’. During the fruit ripening,peel adherence and firmness,which reflect the ease of peeling,remarkably decreased,suggesting that the peeling is easier as the fruit mature. In different varieties,the ease of peeling also showed great diversity. Fremont and Yaoxianggan had higher peel adherence than Mukaiyama and Clementine,and Yaoxianggan had the highest peel firmness in the four varieties,whereas Mukaiyama and Clementine had the similarly lowest peel firmness,indicating that Fremont and Yaoxianggan were hard peeling and Mukaiyama and Clementine were easy peeling. The correlation analysis indicated the significant positive correlation between the peel adherence and firmness,and that the ease of peeling is relevant to the low level of cell wall polysaccharides and high activities of their degradation-related enzymes. The contents of cell wall polysaccharides in all varieties dramatically dropped during the fruit maturation,and coincidently,the activities of some enzymes related to cell wall polysaccharide degradation and the expression level of the encoded genes also ascended. At the same time the expression of some genes encoding xylanase inhibitors and pectin methylesterase inhibitors was decreased. In these four varieties,the peels in the easy-peeling Mukaiyama and Clementine had lower content of total cell wall biomass as well as some polysaccharide fractions including hemicellulose,cellulose and protopectin,which were relevant to the higher activities of xylanase,cellulose and pectin degradation-related enzymes. Nevertheless,the pivot gene controlling the distinct ease of peeling in different varieties remains obscure.

Key words: mandarin, ease of peeling, peel firmness, peel-pulp adherence, cell wall polysaccharides, enzyme activity, gene expression

中图分类号:

S666

张晓楠, 余歆, 叶子茂, 刘小丰, 朱延松, 杨胜男, 王旭, 刘梦雨, 赵晓春. 宽皮柑橘果实的剥皮性及与细胞壁多糖的关系[J]. 园艺学报, 2021, 48(12): 2336-2348.

ZHANG Xiaonan, YU Xin, YE Zimao, LIU Xiaofeng, ZHU Yansong, YANG Shengnan, WANG Xu, LIU Mengyu, ZHAO Xiaochun. Ease of Peeling and Its Relationship with Cell Wall Polysaccharides in Mandarin Fruit[J]. Acta Horticulturae Sinica, 2021, 48(12): 2336-2348.

图/表 7

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编码蛋白 Encoding protein	基因 Gene ID	目的片段长度/nt Amplicon length	引物（5′-3′） Primer sequence
	Ciclev10025866m/ β-actin	102	F：CCAAGCAGCATGAAGATCAA;R：ATCTGCTGGAAGGTGCTGAG
木聚糖酶Xylanase	Ciclev10028089m	165	F：TTGCTGCCAACTTCACAAGC;R：GAAACCTCACCTTGCGCTTG
	Ciclev10028121m	248	F：TTGTGTAGGGTCTGCTGCTG;R：CTCCACTTCCATCTGCTGCA
	Ciclev10000171m	158	F：TCAGGACTGGATTGCAGCAG;R：TTTCCGAACACAGCCCAGTT
木聚糖酶抑制蛋白	Ciclev10005000m	221	F：TGGAACGAAGGTCAGCACTG;R：CGTAGATTTTCCACACGCGG
Xylanase inhibitor	Ciclev10007187m	161	F：GATGTGTCGTGTCTGGGGTT;R：TTGTCGCAAACTGTTCGCTG
	Ciclev10005127m	115	F：AGGGTTTAATGGGTCAGCGG;R：GCACACCACCTCCTCATTCA
	Ciclev10006689m	124	F：CCAGCAGTGCCTCAGATTGA;R：CTCCACCGTCCACAAAACCT
	Ciclev10006962m	130	F：TTGCAAAGGGTGTTACGGGT;R：CCGTTGGCTTTGGTAGAGGA
纤维素酶Cellulase	Ciclev10000600m	112	F：CTGGTCCTGACAAGCACGAT;R：CCTGACAAAGCCACAAGTGC
	Ciclev10019301m	181	F：AACTGGCTGGGGAATGACTG;R：CTGAACATTCCGGGAGCCTT
	Ciclev10020376m	210	F：CTGGACTTTGTGGTGGCAGA;R：GATTCTCGTCAGCACTGCCT
	Ciclev10031098m	112	F：AAGCACGTTGGAAAACCAGC;R：TGCCATTGTCTGCCTTCGAT
多聚半乳糖醛酸酶活性亚基	Ciclev10027523m	196	F：GTGCAAACCAGACTTCAGCTG;R：GACCCGTAAGCTTCCCAACA
Polygalacturonase	Ciclev10019941m	114	F：CGGGATTTCGAGTGGTGTGA;R：TCCATGTTCTCAACGGGCAA
active subunit	Ciclev10004942m	218	F：AGCGAAATGTCTGGTGGCAT;R：GGGAGTGCATCAGGGTCAAA
	Ciclev10020162m	172	F：TTCCGGAATTGCAGTTGGGA;R：CTTGCGCGCGTTTTCCATAT
多聚半乳糖醛酸酶抑	Ciclev10014467m	150	F：CGCTTTTGAGTGTTGGTGGG;R：CTTCCACTCCTGCCCCTAGA
制蛋白PG inhibitor	Ciclev10019113m	150	F：GATTTTCCCACAGGCAAGCG;R：CCTCATCCATCTCTCGGTGC
	Ciclev10000484m	208	F：CTTTCTCTCCGGTCAGCCTC;R：AGGTGCTGCAGGAATTGTGT
果胶裂解酶	Ciclev10004783m	125	F：AAGGGCTGGAACTGGAGATC;R：ATGGAGGAAGACTTGGCTCC
Pectate lyase	Ciclev10020423m	191	F：GGACAAGAACATGCAAGCCA;R：TGTCAGGGGCAGCAAATCTA
	Ciclev10019202m	203	F：ATGTTGTTAGCGACCCAGGG;R：GATGCAAGCACCATTGGCAA
果胶甲酯酶	Ciclev10010616m	172	F：TCTCTCGCGTTGTCTTTGCT;R：TCAGTGAGTTCCCTAGCCCA
Pectin methyl esterase	Ciclev10031872m	174	F：CTTGGGCAGAGCATGGAAGA;R：TCAACCCTCTCAGCTGGACT
	Ciclev10012239m	137	F：TGGGAATGGAGGGACAGGAT;R：TCTCGTTCTCCACTTTGCCC
	Ciclev10027321m	173	F：CATTGAAGGCTCGGTCGACT;R：GAGCACCTGACCCTGTAACC
果胶甲酯酶抑制蛋白	Ciclev10007806m	109	F：CCGGTAGCAGGAATGTGGTT;R：CCCGCCGTGTTTTGAAATGT
Pectin methyl esterase	Ciclev10007940m	103	F：CTGGCACGGGACCTAACAAT;R：AGCTGCATCTGAACAAGGCT
inhibitor	Ciclev10007964m	146	F：CGACATCTACGGGACCATCG;R：AGAAGCCCGTGTTTTGTCCA
	Ciclev10014888m	123	F：CGCCAATTCTACCGCAACTG;R：AGTGTTCTTTTGGCCGCCTA

编码蛋白 Encoding protein	基因 Gene ID	目的片段长度/nt Amplicon length	引物（5′-3′） Primer sequence
	Ciclev10025866m/ β-actin	102	F：CCAAGCAGCATGAAGATCAA;R：ATCTGCTGGAAGGTGCTGAG
木聚糖酶Xylanase	Ciclev10028089m	165	F：TTGCTGCCAACTTCACAAGC;R：GAAACCTCACCTTGCGCTTG
	Ciclev10028121m	248	F：TTGTGTAGGGTCTGCTGCTG;R：CTCCACTTCCATCTGCTGCA
	Ciclev10000171m	158	F：TCAGGACTGGATTGCAGCAG;R：TTTCCGAACACAGCCCAGTT
木聚糖酶抑制蛋白	Ciclev10005000m	221	F：TGGAACGAAGGTCAGCACTG;R：CGTAGATTTTCCACACGCGG
Xylanase inhibitor	Ciclev10007187m	161	F：GATGTGTCGTGTCTGGGGTT;R：TTGTCGCAAACTGTTCGCTG
	Ciclev10005127m	115	F：AGGGTTTAATGGGTCAGCGG;R：GCACACCACCTCCTCATTCA
	Ciclev10006689m	124	F：CCAGCAGTGCCTCAGATTGA;R：CTCCACCGTCCACAAAACCT
	Ciclev10006962m	130	F：TTGCAAAGGGTGTTACGGGT;R：CCGTTGGCTTTGGTAGAGGA
纤维素酶Cellulase	Ciclev10000600m	112	F：CTGGTCCTGACAAGCACGAT;R：CCTGACAAAGCCACAAGTGC
	Ciclev10019301m	181	F：AACTGGCTGGGGAATGACTG;R：CTGAACATTCCGGGAGCCTT
	Ciclev10020376m	210	F：CTGGACTTTGTGGTGGCAGA;R：GATTCTCGTCAGCACTGCCT
	Ciclev10031098m	112	F：AAGCACGTTGGAAAACCAGC;R：TGCCATTGTCTGCCTTCGAT
多聚半乳糖醛酸酶活性亚基	Ciclev10027523m	196	F：GTGCAAACCAGACTTCAGCTG;R：GACCCGTAAGCTTCCCAACA
Polygalacturonase	Ciclev10019941m	114	F：CGGGATTTCGAGTGGTGTGA;R：TCCATGTTCTCAACGGGCAA
active subunit	Ciclev10004942m	218	F：AGCGAAATGTCTGGTGGCAT;R：GGGAGTGCATCAGGGTCAAA
	Ciclev10020162m	172	F：TTCCGGAATTGCAGTTGGGA;R：CTTGCGCGCGTTTTCCATAT
多聚半乳糖醛酸酶抑	Ciclev10014467m	150	F：CGCTTTTGAGTGTTGGTGGG;R：CTTCCACTCCTGCCCCTAGA
制蛋白PG inhibitor	Ciclev10019113m	150	F：GATTTTCCCACAGGCAAGCG;R：CCTCATCCATCTCTCGGTGC
	Ciclev10000484m	208	F：CTTTCTCTCCGGTCAGCCTC;R：AGGTGCTGCAGGAATTGTGT
果胶裂解酶	Ciclev10004783m	125	F：AAGGGCTGGAACTGGAGATC;R：ATGGAGGAAGACTTGGCTCC
Pectate lyase	Ciclev10020423m	191	F：GGACAAGAACATGCAAGCCA;R：TGTCAGGGGCAGCAAATCTA
	Ciclev10019202m	203	F：ATGTTGTTAGCGACCCAGGG;R：GATGCAAGCACCATTGGCAA
果胶甲酯酶	Ciclev10010616m	172	F：TCTCTCGCGTTGTCTTTGCT;R：TCAGTGAGTTCCCTAGCCCA
Pectin methyl esterase	Ciclev10031872m	174	F：CTTGGGCAGAGCATGGAAGA;R：TCAACCCTCTCAGCTGGACT
	Ciclev10012239m	137	F：TGGGAATGGAGGGACAGGAT;R：TCTCGTTCTCCACTTTGCCC
	Ciclev10027321m	173	F：CATTGAAGGCTCGGTCGACT;R：GAGCACCTGACCCTGTAACC
果胶甲酯酶抑制蛋白	Ciclev10007806m	109	F：CCGGTAGCAGGAATGTGGTT;R：CCCGCCGTGTTTTGAAATGT
Pectin methyl esterase	Ciclev10007940m	103	F：CTGGCACGGGACCTAACAAT;R：AGCTGCATCTGAACAAGGCT
inhibitor	Ciclev10007964m	146	F：CGACATCTACGGGACCATCG;R：AGAAGCCCGTGTTTTGTCCA
	Ciclev10014888m	123	F：CGCCAATTCTACCGCAACTG;R：AGTGTTCTTTTGGCCGCCTA

皮层 Peel	剥皮性 Ease of peeling	细胞壁总干物质 Cell wall material	纤维素 Cellulose	半纤维素 Hcellulose	原果胶 Protopectin	水溶性果胶 Water soluble pectin	螯合剂溶性果胶 CDTA-soluble pectin
黄皮层	粘力Adherence	0.89^**	0.83^**	0.91^**	0.84^**	0.79^**	0.89^**
Flavedo	硬度Firmness	0.94^**	0.84^**	0.97^**	0.95^**	0.86^**	0.90^**
白皮层	粘力Adherence	0.83^**	0.79^**	0.94^**	0.82^**	0.61^*	0.47
Albedo	硬度Firmness	0.82^**	0.63^*	0.93^**	0.89^**	0.73^**	0.46
皮层	剥皮性 Ease of peeling	纤维素酶 Cellulase	木聚糖酶 Xylanase	果胶酶 Pectase	多聚半乳糖醛酸酶 Polygalacturonase	果胶裂解酶 Pectate lyase	果胶甲酯酶 Pectin methyl esterase
黄皮层	粘力Adherence	-0.69^**	-0.68^**	-0.70^**	-0.75^**	-0.78^**	-0.46
Flavedo	硬度Firmness	-0.70^**	-0.74^**	-0.75^**	-0.78^**	-0.76^**	-0.50
白皮层	粘力Adherence	-0.21	-0.79^**	-0.73^**	-0.85^**	-0.73^**	-0.53
Albedo	硬度Firmness	0	-0.78^**	-0.79^**	-0.85^**	-0.80^**	-0.48

皮层 Peel	剥皮性 Ease of peeling	细胞壁总干物质 Cell wall material	纤维素 Cellulose	半纤维素 Hcellulose	原果胶 Protopectin	水溶性果胶 Water soluble pectin	螯合剂溶性果胶 CDTA-soluble pectin
黄皮层	粘力Adherence	0.89^**	0.83^**	0.91^**	0.84^**	0.79^**	0.89^**
Flavedo	硬度Firmness	0.94^**	0.84^**	0.97^**	0.95^**	0.86^**	0.90^**
白皮层	粘力Adherence	0.83^**	0.79^**	0.94^**	0.82^**	0.61^*	0.47
Albedo	硬度Firmness	0.82^**	0.63^*	0.93^**	0.89^**	0.73^**	0.46
皮层	剥皮性 Ease of peeling	纤维素酶 Cellulase	木聚糖酶 Xylanase	果胶酶 Pectase	多聚半乳糖醛酸酶 Polygalacturonase	果胶裂解酶 Pectate lyase	果胶甲酯酶 Pectin methyl esterase
黄皮层	粘力Adherence	-0.69^**	-0.68^**	-0.70^**	-0.75^**	-0.78^**	-0.46
Flavedo	硬度Firmness	-0.70^**	-0.74^**	-0.75^**	-0.78^**	-0.76^**	-0.50
白皮层	粘力Adherence	-0.21	-0.79^**	-0.73^**	-0.85^**	-0.73^**	-0.53
Albedo	硬度Firmness	0	-0.78^**	-0.79^**	-0.85^**	-0.80^**	-0.48