126份黄瓜种质资源果实外观品质的遗传多样性分析与筛选
作者: 赵陆滟 许俊强 许彬 吕霞 张应华
摘要 以来自云南、省外及国外的126份黄瓜种质为试料,对其11个果实外观性状进行了测定,通过遗传变异分析、相关性分析、主成分分析和聚类分析方法,对126份黄瓜种质进行遗传多样性分析及综合评价,筛选出优质种质。126份黄瓜种质中刺瘤大小变异系数最大为 83.82%,瓜肉颜色变异系数最小为 16.45%;平均遗传多样性指数为 1.505,瓜横径遗传多样性指数最高,为1.997, 而果肉颜色的遗传多样性指数最低,为0.594。相关性分析结果显示,瓜形指数与瓜长、瓜柄长、单瓜重、瓜把长、瓜皮颜色、刺瘤大小和刺瘤密度呈极显著正相关,与瓜横径和瓜刺颜色呈极显著负相关;瓜皮颜色与瓜柄长、瓜长、瓜形指数、瓜把长、刺瘤密度和瓜肉颜色呈极显著正相关,与瓜刺颜色呈极显著负相关;单瓜重与刺瘤大小呈显著正相关,与瓜长、瓜横径、瓜形指数、瓜把长呈极显著正相关,与瓜肉颜色呈显著负相关。主成分分析结果显示,前4个主成分因子累计贡献率达 79.024%,第一因子看作是瓜长主分量,第二因子看作是瓜刺颜色主分量,第三因子看作是瓜横径主分量,第四因子看作是瓜柄长主分量。聚类分析结果显示,126份黄瓜种质材料分成七大类(Ⅰ~Ⅶ),其中第Ⅰ类和Ⅱ类,含有白皮种质,可用来选育白皮品种;第Ⅴ类,都为水果黄瓜,单性结实率高,具有较高的丰产潜力,在育种中可以筛选作为母本材料,也可用来选育口感好和瓜面光滑的品种;第Ⅵ类和Ⅶ类,瓜大,单性结实率高,具有较高的丰产潜力, 在育种中可以筛选为大瓜型亲本材料。综上所述,126份黄瓜种质具有丰富的遗传多样性,选择育种潜力较大。在黄瓜育种时,可将刺瘤大小、瓜长、瓜横径、瓜形指数、瓜把长等性状作为单瓜重性状进行改良,且选育优良外观果实品种时应注重瓜形、瓜色、刺瘤等性状。
关键词 黄瓜;种质资源;果实外观品质性状;遗传多样性
中图分类号 S 642.2 文献标识码 A 文章编号 0517-6611(2022)15-0039-08
doi: 10.3969/j.issn.0517-6611.2022.15.012
开放科学(资源服务)标识码(OSID):
Genetic Analysis of Fruit Appearance Quality in 126 Cucumber Germplasm Resources
ZHAO Lu-yan1,2,XU Jun-qiang1,XU Bin3 et al
(1.Dian-Tai Engineering Research Center for Characteristic Agriculture Industrialization of Yunnan Province,Yunnan Agricultural University,Kunming,Yunnan 650201;2.Key Laboratory of Economic Plants and Biotechnology,Kunming Institute of Botany,Chinese Academy of Sciences,Kunming,Yunnan 650201;3.College of Landscape and Horticulture,Yunnan Agricultural University,Kunming,Yunnan 650201)
Abstract 126 cucumber germplasm resources were used in this experiment,among them,31 collected from local Yunnan,4 were from other provinces and 91 accessions were from Europe countries.The genetic variation levels of 5 quality traits and 6 quantitative traits were evaluated by using genetic variation analysis,correlation analysis,principal component analysis and cluster analysis.The variation coefficient of papilloma size was maximum (83.82%) and melon flesh color variation coefficient was minimum (16.45%),the average genetic diversity index was 1.505, the genetic diversity index of melon transverse diameter was highest of 1.997 and melon flesh color genetic diversity index was lowest of 0.594.Correlation analysis showed the melon shape index was extremely significantly positively correlated to melon length,carpopodium length,single melon weight,melon handle length,skin color,papilloma size and papilloma density,while it was extremely significantly negatively correlated with melon diameter and papilloma color.Skin color was extremely significantly positively correlated with carpopodium length,melon length,melon shape index,melon handle length,papilloma density and melon flesh color.It was significantly negatively correlated to papilloma color.Single fruit weigh was extremely significantly positively correlated to papilloma size.It was extremely significantly positively correlated to melon length,melon transverse diameter,melon shape index,melon handle length.It was significantly negatively correlated to melon flesh color.Principal component analysis of traits showed that the cumulative contribution rate of the first four principal component factors reached 79.024%.The first factor was regarded as the main component of melon length,the second factor as the main component of papilloma color,the third factor as the main component of melon transverse diameter,and the fourth factor as the main component of carpopodium length.Cluster analysis showed that 126 cucumber accessions were classified into 7 groups.Group I contained white skin germplasm,which could be used to breed white skin varieties.Group VI had high yield potential and could be selected as mother material in breeding since they had high parthenocarpy rate,and could also be used to select fruit cucumber with good taste and smooth surface.Group VI and VII had large fruits,high parthenocarpy rate and high yield potential,which could be used as breeding material for breeding large fruit varieties.126 cucumber germplasm resources had high genetic diversity,and huge potential of selection and breeding.In cucumber breeding,single melon weight could be increased through selection of papilloma size,melon length,melon transverse diameter,melon shape index,melon handle length,the excellent appearance fruit variety of cucumber depended the appearance of the melon shape,melon color and papilloma.
Key words Cucumis sativus;Germplasm resources;Fruit appearance quality;Genetic diversity
黄瓜(Cucumis sativus L.,2n=2x=14)属葫芦科黄瓜属,是世界各地广泛种植的一种重要蔬菜,因其具有丰富的营养价值和一定的保健功效而深受广泛消费者的喜爱[1-2]。近年来,随着人们生活水平的不断提高,对黄瓜安全性和商品质量等性状的要求越来越高,为满足消费者需求,黄瓜品种在不断地更新换代。因此,目前黄瓜育种研究的重要目标是改善果实相关性状[3],一般包括瓜皮颜色、瓜刺颜色、刺瘤大小、刺瘤稀密、瓜长、瓜横径、瓜把长、瓜肉颜色及单瓜重等性状[4]。根据研究角度不同,可以把黄瓜的果实品质分为3类,分别是外观(商品)品质、营养品质以及风味品质。而果实外观品质性状一直都是黄瓜研究的重点[5-8],因为黄瓜的外观品种直接刺激消费者的购买欲望,且直接影响黄瓜的商品价值及经济价值[9]。近几年,有关果实外观品质性状的研究集中于我国部分地区地方品种及已育成的商品种,对野生种、区域适应性极强的本土品种(我国云南、湖北)及国外(欧洲国家) 种质果实性状鉴定及遗传多样性分析的研究较少。笔者以收集的31份云南地方种质、4份省外湖北黄瓜种质和91份国外欧洲国家黄瓜种质为试材,通过温室内小区地块种植对其11个相关农艺性状进行观测,并进行果实性状的遗传变异、相关性、主成分和聚类分析及营养品质综合评价,筛选出综合性状优良的品种,以期为我国今后选择具有优良性状的黄瓜品种提供理论依据。
1 材料与方法
1.1 试验材料
从国内外收集黄瓜种质126份,其中云南省31份(表1)、湖北省4份(表2)及欧洲地区91份(表3)。
1.2 试验设计
参试种质资源于2019年4月播种于云南农业大学云南省滇台特色农业产业化工程研究中心蔬菜温室大棚内,每份材料每个小区播种20株,分为2行,株行距25 cm×30 cm,播种前提前置于28 ℃黑暗恒温箱进行催芽,并选择露白萌发的种子进行双粒点播。栽培管理均按黄瓜常规生产种植管理进行。
1.3 农艺性状指标测定及标准
在盛果期进行果实性状统计,每个材料小区随机选取3~6条达到商品成熟度的正常瓜进行性状调查,包括瓜皮颜色、瓜刺颜色、刺瘤大小、刺瘤稀密、瓜柄长、瓜长、瓜横径、瓜形指数、瓜把长、瓜肉颜色及单瓜重,调查后进行数据统计分析。性状数据采集和测量方法及标准主要参照李锡香等[4]的《黄瓜种质资源描述规范和数据标准制定的原则和方法》,并结合种植后结果时期的实际生长情况进行。
1.4 数据标准化处理和分析
上述11个农艺性状中,瓜柄长、瓜长、瓜横径、瓜形指数、瓜把长及单瓜重6个为数量性状,其他5个为质量性状。参照李锡香等[4]的《黄瓜种质资源描述规范和数据标准制定的原则和方法》对11个果实性状进行赋值。在计算遗传多样性指数时,因数量性状统计的数值较多,需对数量性状原数据进行分级处理[10-11],即将原数据分成10个等级,1级<x-2δ,中间每级间隔0.5δ,10级>x+2δ(x为原数据平均值,δ为原数据标准差)(表4),质量性状则直接按赋值结果分级。
1.5 统计分析
试验数据采用Excel 2010进行统计整理,计算果实性状的平均值、标准差、变异系数,利用SPSS 17.0 计算遗传多样性指数(Shannon-Weaver多样性指数,H′)[2],计算公式:H′=-PilnPi,其中,Pi为性状第i级别内材料份数占总份数的百分比。并采用SPSS 17.0进行相关性及主成分分析。采用DPS 2008进行聚类分析,聚类分析方法采用欧氏距离及离差平方和法选择进行,为消除性状单位不统一对数据分析的影响,故数据转化方式选择标准化转换[9]。
2 结果与分析
2.1 黄瓜种质资源果实性状变异情况
由表5可知,在黄瓜果实性状方面,瓜柄长、单瓜重、瓜长、瓜横径、瓜形指数、瓜把长、瓜皮颜色、瓜刺颜色、刺瘤大小、刺瘤密度和瓜肉颜色的变异系数差异明显,其中刺瘤大小变异系数最大,达83.82%,变异系数最小的为瓜肉颜色,为16.45%。表明这些种质资源刺瘤大小的类型较为丰富,而瓜肉颜色类型较为单一。
2.2 黄瓜种质资源果实性状遗传多样性分析
基于126份种质材料的果实性状测定结果计算遗传多样性指数,结果见表6。由表6可知,11个果实性状的平均遗传多样性指数为1.505,不同性状的遗传多样性指数差异较大,其中瓜柄长、单瓜重、瓜长、瓜横径、瓜形指数、瓜皮颜色、瓜把长、瓜刺颜色、刺瘤大小、刺瘤密度10个性状的遗传多样性指数均大于1,瓜横径遗传多样性指数最高,为1.997,而瓜肉颜色的遗传多样性指数小于1,其遗传多样性指数最低,为0.594。可见,数量性状的遗传多样性明显高于质量性状,可能与质量赋值相关,但平均遗传多样性指数较质量性状高,说明该研究中所收集到的种质材料遗传多样性丰富。
2.3 黄瓜种质资源农艺性状相关性分析
对126份黄瓜种质资源的11个果实性状进行相关性分析,结果见表7。由表7可知,瓜形指数与瓜长、瓜柄长、单瓜重、瓜把长、瓜皮颜色、刺瘤大小和刺瘤密度呈极显著正相关,与瓜横径和瓜刺颜色呈极显著负相关;瓜皮颜色与瓜柄长、瓜长、瓜形指数、瓜把长、刺瘤密度和瓜肉颜色呈极显著正相关,与瓜刺颜色呈极显著负相关。可见,果实在瓜形、瓜色、刺瘤等外观品质方面存在紧密的关联性。在瓜重方面,单瓜重与刺瘤大小呈显著正相关,与瓜长、瓜横径、瓜形指数、瓜把长呈极显著正相关,与瓜肉颜色呈显著负相关。综上所述,可以通过刺瘤大小、瓜长、瓜横径、瓜形指数和瓜把长等性状选择单瓜重高的材料。