柑橘2个三倍体有性后代群体果实品质性状的遗传特点

管书萍1,王婷婷1,周阳广1,朱虹娴1,伍小萌1,龙春瑞2,高俊燕2,郭文武1,解凯东1*

1华中农业大学园艺林学学院·果蔬园艺作物种质创新与利用全国重点实验室,武汉 430070;2云南省农业科学院热带亚热带经济作物研究所,云南保山 678000)

摘 要:【目的】研究柑橘三倍体有性后代果实品质性状的遗传特点,为倍性杂交创制无核三倍体新种质科学选配亲本提供理论依据。【方法】以柑橘二倍体品种秋辉橘、清见橘橙为母本,异源四倍体体细胞杂种橘柚+甜橙(NS)、甜橙+红橘(SD)为父本倍性杂交获得的2个三倍体有性后代群体成熟果实为材料,通过测定其果实横纵径、单果质量、果皮厚度、可溶性固形物和可滴定酸含量等性状,探究柑橘三倍体有性后代果实品质性状的遗传特点。【结果】三倍体后代单果质量和果实横径平均值均介于双亲之间,呈趋中变异;果实纵径变化趋势在2个组合间有差异,秋辉橘×NS组合后代呈趋大变异,而清见橘橙×SD组合则呈趋中变异;果皮厚度平均值均大于亲中值且多数高于高值亲本,存在一定程度的超高亲本遗传现象;2个组合三倍体有性后代果实可溶性固形物含量平均低低亲比率分别为74.4%、66.88%,呈趋小变异;而2个三倍体有性后代群体果实可滴定酸含量平均值均低于亲中值,且不同年份间酸含量介于亲本间和低于低值亲本的后代比例较高。【结论】推测柑橘三倍体有性后代果实单果质量、果实横径、纵径、果形指数、果皮厚度和可溶性固形物含量性状是由多基因控制的数量性状,可滴定酸含量性状可能存在主效控制基因。

关键词:柑橘;三倍体;倍性育种;果实性状;遗传倾向

柑橘(Citrus L.)是世界第一大水果,也是我国南方最重要的果树[1],是柑橘产区乡村振兴和农民脱贫致富的支柱产业。我国柑橘主要用于鲜食,培育果实品质佳的新品种是柑橘核心育种目标[2-3]。柑橘果实品质主要由外观品质和内在品质共同决定,包括果实大小(横、纵径)、质量、果皮颜色、果皮厚度、可溶性固形物和有机酸含量等[4-5]。关于果实品质性状遗传规律的研究在梨、葡萄、李、杏和枇杷等多种果树中已有报道[6-17],认为果实外观品质性状和可溶性固形物含量在大多数果树中为多基因控制的数量性状,杂交后代呈正态分布;但可滴定酸含量一般呈偏正态分布,可能为主效基因和微效基因共同控制的复杂性状。上述研究多以二倍体为研究对象,关于果树多倍体果实品质性状遗传特点的报道较少。

柑橘三倍体一般果实无核,且由于倍性增加,果实有益代谢物含量可能增加。因此,培育三倍体是获得无核且品质优良柑橘新品种的重要途径[18]。但柑橘多数品种存在多胚性,常规杂交难以获得有性后代。利用单胚性品种为母本与四倍体倍性杂交[19-21],虽然在一定程度上可克服珠心胚干扰,但三倍体胚在发育早期易败育,往往需借助幼胚离体挽救培养才能再生三倍体,耗时长且难以获得较大的三倍体群体,导致对柑橘三倍体有性后代果实相关性状的遗传规律知之甚少。针对我国柑橘地方良种多数有核的问题,华中农业大学以二倍体为母本与四倍体倍性杂交,创制了3500余株柑橘三倍体新种质,部分已经连续开花结果多年,为研究柑橘三倍体果实性状遗传特点奠定了宝贵的材料基础。笔者在本研究中以前期秋辉橘、清见橘橙为母本倍性杂交创制的2 个三倍体有性后代群体为材料,对其果实大小、果实质量、果皮厚度、果实可溶性固形物和可滴定酸含量等品质性状进行测定,探讨三倍体有性后代果实品质性状的遗传特点,为未来三倍体育种亲本选配和无核新品种培育奠定理论基础。

1 材料和方法

1.1 试验材料

课题组前期以秋辉橘{[Citrus reticulata Blanco×(C.paradis Macf.×C.reticulata Blanco)]×(C.reticulata Blanco × C. sinensis Osbeck)}和清见橘橙(C.unshiu Marcow.×C.sinesis Osbeck)为母本,异源四倍体体细胞杂种Nova橘柚+Succari甜橙(C.reticu-lata Blanco × C. paradis Macf + C. sinensis Osbeck,简称NS)、Succari甜橙+Dancy红橘(C.sinensis Osbeck+C.reticulata Blanco,简称SD)为父本,进行倍性杂交培育的2 个三倍体有性群体为材料[19],探究三倍体后代果实品质性状的遗传特点。秋辉橘×NS组合共155株三倍体后代,2018和2019年分别有43株和50株后代开花结果;秋辉橘×NS组合共135株三倍体后代,2018 和2019 年分别有34 株和43 株开花结果。上述材料定植于云南省农业科学院热带亚热带经济作物研究所,株行距3.0 m×4.0 m。果实成熟期,每个样品随机采摘树冠外围不同方向、果实大小有代表性且无病虫害的果实12个,对果实横纵径、果实质量、果皮厚度、果实可溶性固形物和可滴定酸含量进行测定。

1.2 试验方法

1.2.1 果实横纵径、单果质量和果皮厚度测定 果实横纵径、果皮厚度采用游标卡尺进行测量。果实赤道面最宽的直径为果实横径,果顶到果蒂的距离为果实纵径;果实赤道面的果皮厚度为果皮厚度,每个果实取不同部位测量3 次取平均值;果实单果质量采用百分之一电子天平测定。

1.2.2 可溶性固形物和可滴定酸含量测定 果实可溶性固形物和可滴定酸含量采用糖酸一体机(Atago,日本)进行测定。4 个果实为一组,将其果汁挤入同一个杯子为1 个生物学重复,设置3 次生物学重复。糖酸一体机校准后,每个生物学重复吸取100µL 混匀的果汁滴于糖酸一体机传感器上,测定其可溶性固形物含量;随后吸取4.9 mL去离子水加至传感器上,将果汁稀释50倍后再测定可滴定酸含量,每个生物学重复测定3次。

1.2.3 数据统计 用Excel 2020对数据进行整理和分析。参考崔艳波等[6]的方法对三倍体有性后代群体果实横纵径、单果质量、果皮厚度、可溶性固形物和可滴定酸含量的亲中值、杂交群体的平均值、变异系数、遗传传递力进行计算。超高亲比率和低低亲比率的计算参考刘有春等[11]的方法。

2 结果与分析

2.1 三倍体有性后代群体果实横、纵径的遗传特点

秋辉橘×NS和清见橘橙×SD 2个组合三倍体有性后代群体果实横径和纵径频率分布如图1 所示,均趋近于正态分布,为典型的数量性状遗传特征,表明三倍体后代的果实横纵径可能为多基因控制的数量性状。由表1可知,2个三倍体有性后代群体果实横径平均值均低于亲中值但高于低值亲本,且杂交后代果实横径多介于亲本之间,表现趋中变异。如清见橘橙×SD 组合三倍体后代果实横径介于双亲间的比率分别为67.65%(2018 年)和83.78%(2019年)。与果实横径不同,不同组合三倍体有性后代果实纵径的遗传趋势不同,秋辉橘× NS 组合2018 和2019 年果实纵径超高亲比率分别为60.47%和42.00%,表现出超亲遗传变异趋势;而清见橘橙×SD组合2018和2019年果实纵径介于亲本之间的比率分别为94.12%和97.30%,呈趋中变异(表2)。对果实横纵径的变异系数和遗传传递力进行分析,2个杂交组合连续2 a(年)果实横纵径的变异系数均较小但遗传传递力较高(表1 和表2),如秋辉橘×NS 组合2018 和2019 年横径的变异系数分别为13.26%和14.61%,遗传传递力分别为96.40%和93.18%;纵径变异系数分别为13.74%和15.53%,遗传传递力分别为107.20%和102.96%,表明三倍体有性杂交后代果实横纵径变异程度较小,但主要由遗传因素决定。

表1 2 个三倍体有性后代群体果实横径的遗传变异
Table 1 Variation and inheritance of fruit transverse diameter in the two triploid hybrid populations

注:MP.亲中值;x.杂交群体的平均值;CV.变异系数;Ta.遗传传递力。下同。
Note:MP.Median parental value;x.Population average value;CV.Coefficient of variation;Ta.Genetic transmitting ability.The same below.

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表2 2 个三倍体有性后代群体果实纵径的遗传变异
Table 2 Variation and inheritance of fruit longitudinal diameter in the two triploid hybrid populations

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图1 三倍体有性后代群体果实横径(A、B)、果实纵径(C、D)、单果质量(E、F)、果皮厚度(G、H)的频率分布
Fig.1 The frequency distribution of fruit transverse diameter(A,B),fruit longitudinal diameter(C,D),fruit weight(E,F),thickness of peel(G,H)in two triploid hybrid populations

A、C、E、G 为秋辉橘×NS 组合;B、D、F、H 为清见橘橙×SD 组合。
A,C,E,G refer to the cross of Fallglo mandarin×NS;B,D,F,H refer to the cross of Kiyomi tangor×SD.

2.2 三倍体有性后代群体单果质量和果皮厚度的遗传特点

2 个三倍体有性后代群体的单果质量、果皮厚度的频率分布也趋近于正态分布(图1),且不同年份间规律相似,表明三倍体有性后代的单果质量和果皮厚度也为多基因控制的数量性状。对单果质量和果皮厚度的遗传特点分析表明,2 个三倍体有性后代群体平均单果质量在不同年份间均低于亲中值但高于低值亲本且多数介于亲本之间,表现趋中变异;而2 个三倍体有性后代群体的果皮厚度平均值连续2 a均大于亲中值且多数高于高值亲本,表明三倍体有性后代果皮厚度表现超亲遗传特点,大部分三倍体后代果皮变厚。进一步对三倍体单果质量、果皮厚度的变异系数进行分析,发现2 个三倍体有性后代群体单果质量的变异系数在不同年份间均较大(表3),但果皮厚度连续2 a 的变异系数偏小(表4),表明三倍体有性后代的单果质量易发生性状分离,而果皮厚度分离程度有限。对2 个三倍体有性后代群体单果质量和果皮厚度的遗传力分析表明,不同组合单果质量的遗传力不同;如秋辉橘×NS连续2 a 单果质量的遗传传递力均较高(99.79%和91.84%),而清见橘橙×SD 组合的遗传传递力比较低(55.93%和63.30%),表明不同组合三倍体有性后代的单果质量遗传受亲本影响较大。2个三倍体有性后代群体果皮厚度的遗传传递力均较高(表4),表明三倍体有性后代果皮厚度性状主要由遗传因素决定。

表3 2 个柑橘三倍体有性后代群体单果质量的遗传变异
Table 3 Variation and inheritance of fruit mass in the two triploid hybrid populations of citrus

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表4 2 个三倍体有性后代群体果皮厚度的遗传变异
Table 4 Variation and inheritance of peel thickness in the two triploid hybrid populations

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2.3 三倍体有性后代群体果实可溶性固形物和可滴定酸含量的遗传特点

2个三倍体有性后代群体果实可溶性固形物含量的频率分布连续2 a呈正态分布,而可滴定酸含量则呈偏正态分布(图2),表明柑橘三倍体有性后代可溶性固形物含量为数量性状,而可滴定酸含量则可能存在主效控制基因。且2个三倍体有性后代群体果实可溶性固形物含量平均值连续2 a 均小于亲中值且低低亲比率较高,表明可溶性固形物含量总体呈趋小变异。如秋辉橘×NS组合连续2 a的低低亲比率分别为84.62%和64.29%。2 个三倍体有性后代群体的可滴定酸含量平均值低于亲中值高于低亲值,且杂交后代可滴定酸含量多介于亲本之间或低于低值亲本,呈趋中或趋小变异,2个三倍体后代的果实可滴定酸含量连续2 a 介于双亲间的平均比率分别为58.79%(秋辉橘× NS)和52.98%(清见橘橙×SD),低于双亲的平均比率分别为33.29%(秋辉橘×NS)和37.57%(清见橘橙×SD)。

图2 三倍体有性后代群体可溶性固形物(A、B)、可滴定酸(C、D)含量的频率分布
Fig.2 The frequency distribution of soluble solid content(A,B),titratable acid content(C,D)in two triploid hybrid populations

A、C 为秋辉橘×NS 组合;B、D 为清见橘橙×SD 组合。
A,C refer to the cross of Fallglo mandarin×NS;B,D refer to the cross of Kiyomi tangor×SD.

对2个三倍体有性后代群体果实可溶性固形物和可滴定酸含量的变异系数和遗传传递力分析表明,2 个三倍体有性后代群体果实可溶性固形物含量变异系数均较小,未出现广泛的性状分离(表5);而2个三倍体有性后代群体果实可滴定酸含量的变异系数连续2 a 均较高,表现出现广泛的性状分离,选择潜力较大(表6);且2个性状的遗传传递力均较高,表明三倍体有性后代果实糖酸变异主要受遗传因素影响。

表5 三倍体有性后代群体果实可溶性固形物含量的遗传变异
Table 5 Inheritance and variation of soluble solids content in the fruits of two triploid hybrid populations

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表6 三倍体有性后代群体果实可滴定酸含量的遗传变异
Table 6 Inheritance and variation of titratable acid(TA)content in the fruits of two triploid hybrid populations

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3 讨 论

3.1 不同亲本组合对三倍体有性后代果实外观品质的影响

柑橘外观品质通常包括果实大小、果实形状、果皮颜色及光泽度、果皮厚度和果实整齐度等,其中果实大小(果实横纵径)、果实质量和果皮厚度是衡量柑橘果实的重要经济性状指标。因此,笔者在本研究中着重对秋辉橘×NS和清见橘橙×SD 2个三倍体有性后代群体的果实横纵径、单果质量和果皮厚度3 个外观品质性状的遗传特点进行了评价,上述性状在2个组合三倍体后代中频次分布均呈现连续正态分布,推测均为多基因共同控制的数量性状。2个三倍体有性后代群体的果实横径和单果质量表现出相同的遗传倾向,杂交后代果实横径和单果质量平均值均低于亲中值高于低亲亲本,呈现趋中偏小变异,且单果质量变异系数较大,后代分离广泛,可能是由亲本的非加性效应解体造成的。与果实横径和单果质量的遗传倾向不同,2 个三倍体有性后代群体的果实纵径表现出不同的遗传倾向,秋辉橘×NS 组合呈现出趋大遗传变异,而清见橘橙×SD 组合呈趋中变异。该结果与前人在梨和枇杷中的报道差别较大(杂交后代果实横径、纵径和果实质量呈趋小变异)[6,16,22],可能是因为前人所用材料为二倍体间的有性杂交后代,后代倍性与父母本一致,而笔者在本研究中所用材料为二倍体与四倍体倍性杂交获得的三倍体有性后代,后代由于倍性增加,大多数表现出果实大于二倍体母本(器官巨大性)的特点,为培育柑橘大果无核新品种提供了数据支撑。

2个三倍体有性后代群体的果皮厚度平均值均高于亲中值且多数高于高值亲本,呈现超亲遗传变异,遗传传递力均高于100%,变异系数较小,表明三倍体有性后代果皮厚度分离程度有限,受环境影响较小,遗传稳定,该结果与前人在红美人上的研究结果一致[23]。但三倍体后代中也存在部分株系果皮厚度较双亲薄的情况,如清见橘橙×SD组合三倍体有性后代在2018 年和2019 年的低低亲比率分别为9.09%和16.22%,为培育无核且果皮薄的柑橘新品种提供了宝贵的育种材料。

3.2 不同亲本组合对三倍体有性后代群体果实内在品质的影响

可溶性糖和有机酸含量是影响柑橘果实内在品质的重要风味物质,其含量和比例决定了柑橘果实的口感和风味[4,24-25],是评价柑橘品种是否优良的重要指标。在实际的果实品质评价过程中,通常用可溶性固形物和可滴定酸含量2个指标来衡量柑橘果实的可溶性糖和有机酸含量,因此笔者在本研究中通过测定2个三倍体有性后代群体的可溶性固形物和可滴定酸含量来评价三倍体有性后代果实可溶性糖和有机酸的遗传倾向。结果显示2个三倍体有性后代群体的可溶性固形物和可滴定酸含量均低于亲中值,且可溶性固形物含量的低低亲比率均较高,表现为趋小变异,这与前人在越橘[11]和柑橘[26]上的报道一致,暗示出未来要想培育出高糖的三倍体无核优系,亲本必须选择可溶性固形物含量高的品种或材料。在本研究中,2 个三倍体有性后代群体果实可滴定酸含量平均值均低于亲中值,且不同年份间含量介于亲本间和低于低值亲的后代比例较高,该结果与王婷婷等[26]的结果(50%以上的三倍体后代可滴定酸含量超过高酸亲本)差别较大,推测可能是母本的不同对三倍体酸含量的影响较大,这为未来培育低酸的三倍体新品种提供了思路,可选择类似清见橘橙和秋辉橘的二倍体母本与四倍体倍性杂交创制三倍体新种质,培育低酸无核的三倍体新品种。

4 结 论

2 个三倍体有性后代群体的单果质量、果实横径和可滴定酸含量均呈趋中变异,果皮厚度呈超亲遗传;可溶性固形物含量呈趋小变异,果实纵径不同组合遗传倾向不同;单果质量和可滴定酸含量变异系数大,后代易出现性状分离,而其他性状变异系数小;几个性状的遗传传递力高低顺序依次为果皮厚度>果实纵径>果实横径>可滴定酸含量>可溶性固形物含量>单果质量,遗传传递力越高,杂种优势越明显,为未来倍性杂交创制三倍体的亲本选配奠定了理论基础。

参考文献References:

[1] 郭文武,叶俊丽,邓秀新.新中国果树科学研究70 年:柑橘[J].果树学报,2019,36(10):1264-1272.GUO Wenwu,YE Junli,DENG Xiuxin. Fruit scientific research in New China in the past 70 years:Citrus[J]. Journal of Fruit Science,2019,36(10):1264-1272.

[2] 邓秀新.中国柑橘育种60 年回顾与展望[J].园艺学报,2022,49(10):2063-2074.DENG Xiuxin.A review and perspective for Citrus breeding in China during the last six decades[J].Acta Horticulturae Sinica,2022,49(10):2063-2074.

[3] NAVARRO L,ALEZA P,CUENCA J,JUÁREZ J,PINA J A,ORTEGA C,NAVARRO A,ORTEGA V. The mandarin triploid breeding program in Spain[J]. Acta Horticulturae,2015(1065):389-395.

[4] HUSSAIN S B,SHI C Y,GUO L X,KAMRAN H M,SADKA A,LIU Y Z.Recent advances in the regulation of citric acid metabolism in Citrus fruit[J]. Critical Reviews in Plant Sciences,2017,36(4):241-256.

[5] RAO M J,ZUO H,XU Q.Genomic insights into citrus domestication and its important agronomic traits[J]. Plant Communications,2021,2(1):100138.

[6] 崔艳波,陈慧,乐文全,张树军,伍涛,陶书田,张绍铃.‘京白梨’与‘鸭梨’正反交后代果实性状遗传倾向研究[J].园艺学报,2011,38(2):215-224.CUI Yanbo,CHEN Hui,LE Wenquan,ZHANG Shujun,WU Tao,TAO Shutian,ZHANG Shaoling. Studies on genetic tendency of fruit characters in reciprocal crosses generation between‘Jingbaili’and‘Yali’pear cultivars[J]. Acta Horticulturae Sinica,2011,38(2):215-224.

[7] 高洪娜,张武杰,刘凤芝,徐德海,周文志.黑穗醋栗杂交后代部分性状的遗传倾向[J]. 分子植物育种,2021,19(23):7932-7937.GAO Hongna,ZHANG Wujie,LIU Fengzhi,XU Dehai,ZHOU Wenzhi.Genetic tendency of some characters in the hybrid progeny of black currant (Ribes nigrum L.) [J]. Molecular Plant Breeding,2021,19(23):7932-7937.

[8] 郭权,郭印山,郭修武.葡萄‘红地球’与‘双优’杂交后代果实糖酸的遗传规律[J].分子植物育种,2021,19(10):3424-3431.GUO Quan,GUO Yinshan,GUO Xiuwu. Genetic law of sugar and acid in the fruits of hybrids between‘Red globe’and‘Shuangyou’[J]. Molecular Plant Breeding,2021,19(10):3424-3431.

[9] 李俊才,伊凯,刘成,隋洪涛,王家珍.梨果实部分性状遗传倾向研究[J].果树学报,2002,19(2):87-93.LI Juncai,YI Kai,LIU Cheng,SUI Hongtao,WANG Jiazhen.Studies on the trend of inheritance of some characters of pear fruit[J].Journal of Fruit Science,2002,19(2):87-93.

[10] 刘家成,章秋平,牛铁泉,刘宁,张玉萍,徐铭,马小雪,张玉君,刘硕,刘威生.’串枝红’与‘赛买提’杏正、反交后代果实性状遗传倾向分析[J].果树学报,2020,37(5):625-634.LIU Jiacheng,ZHANG Qiuping,NIU Tiequan,LIU Ning,ZHANG Yuping,XU Ming,MA Xiaoxue,ZHANG Yujun,LIU Shuo,LIU Weisheng.Analysis of inherited tendency of fruit characteristics in F1 group of reciprocal crossing between‘Chuanzhihong’and‘Saimaiti’in apricots[J]. Journal of Fruit Science,2020,37(5):625-634.

[11] 刘有春,鄂辉邦,刘成,王兴东,杨艳敏,孙斌,张舵,袁兴福,魏永祥.越橘半同胞系杂交后代果实糖酸性状的变异和遗传倾向[J].果树学报,2016,33(6):664-675.LIU Youchun,E Huibang,LIU Cheng,WANG Xingdong,YANG Yanmin,SUN Bin,ZHANG Duo,YUAN Xingfu,WEI Yongxiang.Variability and inheritance of sugar and acid content in blueberry (Vaccinium) fruit of half-sib crosses[J]. Journal of Fruit Science,2016,33(6):664-675.

[12] 刘政海,董志刚,李晓梅,谭敏,杨镕兆,杨兆亮,唐晓萍.‘威代尔’与‘霞多丽’葡萄杂交F1 代果实性状遗传倾向分析[J].果树学报,2020,37(8):1122-1131.LIU Zhenghai,DONG Zhigang,LI Xiaomei,TAN Min,YANG Rongzhao,YANG Zhaoliang,TANG Xiaoping. Inheritance trend of fruit traits in F1 progenies of‘Vidal’and‘Chardonnay’of grape[J].Journal of Fruit Science,2020,37(8):1122-1131.

[13] 武晓红,景晨娟,陈雪峰,赵习平,袁立勇,梁爽,张宪成,唐焕英,李立颖.‘金太阳’与‘串枝红’杏正反交后代果实性状的遗传倾向研究[J].江西农业学报,2018,30(10):13-18.WU Xiaohong,JING Chenjuan,CHEN Xuefeng,ZHAO Xiping,YUAN Liyong,LIANG Shuang,ZHANG Xiancheng,TANG Huanying,LI Liying. Studies on genetic tendency of fruit characters in F1 generation of reciprocal crosses between apricot cultivars‘Jintaiyang’and‘Chuanzhihong’[J]. Acta Agriculturae Jiangxi,2018,30(10):13-18.

[14] 徐豆,付鸿博,杜灵敏,郭晋鸣,杜俊杰,王鹏飞,穆霄鹏,张建成.欧李正反交F1 果实性状的遗传变异分析[J].山西农业科学,2020,48(5):696-699.XU Dou,FU Hongbo,DU Lingmin,GUO Jinming,DU Junjie,WANG Pengfei,MU Xiaopeng,ZHANG Jiancheng. Genetic variation analysis of fruit traits in positive and negative cross F1 generation of Chinese dwarf cherry[J]. Journal of Shanxi Agricultural Sciences,2020,48(5):696-699.

[15] 许家辉,余东,魏秀清,许玲,蒋际谋,黄金松.枇杷正反交杂种后代果实性状遗传分析[J]. 云南农业大学学报,2008,23(5):663-667.XU Jiahui,YU Dong,WEI Xiuqing,XU Ling,JIANG Jimou,HUANG Jinsong.Genetic analysis of fruit agronomic characters in reciprocal hybrid progeny of loquat[J].Journal of Yunnan Agricultural University(Natural Science),2008,23(5):663-667.

[16] 赵崇斌,郭乙含,李舒庆,徐红霞,黄天启,林顺权,陈俊伟,杨向晖.宁海白×大房枇杷F1 杂交群体果实性状的相关性及遗传分析[J].果树学报,2021,38(7):1055-1065.ZHAO Chongbin,GUO Yihan,LI Shuqing,XU Hongxia,HUANG Tianqi,LIN Shunquan,CHEN Junwei,YANG Xianghui. Correlation and genetic analysis of fruit traits in F1 hybrid population of loquat generated from Ninghaibai × Dafang[J].Journal of Fruit Science,2021,38(7):1055-1065.

[17] 刘月,刘海楠,邓宇,刘禹姗,殷秀岩,孙海悦,李亚东.越橘正反交后代部分性状的遗传倾向[J].吉林农业大学学报,2019,41(1):35-41.LIU Yue,LIU Hainan,DENG Yu,LIU Yushan,YIN Xiuyan,SUN Haiyue,LI Yadong. Genetic predisposition of some traits of blueberry in hybrid progenies[J]. Journal of Jilin Agricultural University,2019,41(1):35-41.

[18] CUENCA J,GARCÍA-LOR A,JUÁREZ J,PINA J A,NAVARRO L,ALEZA P.Alborea:a new mid-late mandarin triploid hybrid [(Citrus clementina × C. tangerina) × (C. nobilis × C. deliciosa)[J].HortScience,2020,55(8):1387-1392.

[19] 解凯东,彭珺,袁东亚,强瑞瑞,谢善鹏,周锐,夏强明,伍小萌,柯甫志,刘高平,GROSSER J W,郭文武.以本地早橘和槾橘为母本倍性杂交创制柑橘三倍体[J].中国农业科学,2020,53(23):4961-4968.XIE Kaidong,PENG Jun,YUAN Dongya,QIANG Ruirui,XIE Shanpeng,ZHOU Rui,XIA Qiangming,WU Xiaomeng,KE Fuzhi,LIU Gaoping,GROSSER J W,GUO Wenwu.Production of citrus triploids based on interploidy crossing with bendizao and man tangerines as female parents[J].Scientia Agricultura Sinica,2020,53(23):4961-4968.

[20] 解凯东,王惠芹,王晓培,梁武军,谢宗周,伊华林,邓秀新,GROSSER J W,郭文武.单胚性二倍体为母本与异源四倍体杂交大规模创制柑橘三倍体[J].中国农业科学,2013,46(21):4550-4557.XIE Kaidong,WANG Huiqin,WANG Xiaopei,LIANG Wujun,XIE Zongzhou,YI Hualin,DENG Xiuxin,GROSSER J W,GUO Wenwu. Extensive Citrus triploid breeding by crossing monoembryonic diploid females with allotetraploid male parents[J].Scientia Agricultura Sinica,2013,46(21):4550-4557.

[21] 宋健坤,郭文武,伊华林,刘继红,陈春丽,邓秀新.以异源四倍体体细胞杂种为父本与二倍体杂交创造柑橘三倍体的研究[J].园艺学报,2005,32(4):594-598.SONG Jiankun,GUO Wenwu,YI Hualin,LIU Jihong,CHEN Chunli,DENG Xiuxin. Creation of triploid Citrus plants by crossing elite allotetraploid somatic hybrid pollen parents with diploid cultivars[J].Acta Horticulturae Sinica,2005,32(4):594-598.

[22] 白牡丹,郝国伟,张晓伟,杨盛,郭黄萍.‘玉露香梨’与‘黄冠’梨杂交后代果实性状遗传倾向的初步研究[J].中国果树,2017(增刊1):13-16.BAI Mudan,HAO Guowei,ZHANG Xiaowei,YANG Sheng,GUO Huangping. Primary research on genetic tendency of fruit characters in hybrid progenies between‘Yuluxiangli’and‘Huangguan’pear cultivars[J].China Fruits,2017(Suppl.1):13-16.

[23] 郑妮.‘红美人’柑橘杂交后代群体果实主要性状的遗传分析及早熟优株的筛选[D].重庆:西南大学,2021.ZHENG Ni. Genetic analysis of major fruit traits in the hybrid offspring of Citrus‘Hongmeiren’and screening for the superior early-maturing varieties[D]. Chongqing:Southwest University,2021.

[24] SUN L F,NASRULLA H,KE F Z,NIE Z P,WANG P,XU J G.Citrus genetic engineering for disease resistance:past,present and future[J].International Journal of Molecular Sciences,2019,20(21):5256.

[25] AHMED D,EVRARD J C,OLLITRAULT P,FROELICHER Y.The effect of cross direction and ploidy level on phenotypic variation of reciprocal diploid and triploid mandarin hybrids[J].Tree Genetics&Genomes,2020,16(1):25.

[26] 王婷婷,周阳广,朱虹娴,张苗,段耀园,曹惠祥,管书萍,解凯东,伍小萌,龙春瑞,高俊燕,郭文武.2 个柑橘三倍体有性群体果实糖酸性状遗传评价[J].果树学报,2022,39(7):1147-1156.WANG Tingting,ZHOU Yangguang,ZHU Hongxian,ZHANG Miao,DUAN Yaoyuan,CAO Huixiang,GUAN Shuping,XIE Kaidong,WU Xiaomeng,LONG Chunrui,GAO Junyan,GUO Wenwu. Inheritance of sugar and acid contents in the fruits of triploid hybrids originated from two 2x×4x crosses with Nadorcott tangor as a female parent[J].Journal of Fruit Science,2022,39(7):1147-1156.

Inheritance of some quality traits of the fruits in triploid hybrids derived from two citrus 2x×4x interploidy crosses

GUAN Shuping1, WANG Tingting1, ZHOU Yangguang1, ZHU Hongxian1, WU Xiaomeng1, LONG Chunrui2,GAO Junyan2,GUO Wenwu1,XIE Kaidong1*

(1College of Horticulture&Forestry Sciences,Huazhong Agricultural University/National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops,Wuhan 430070,Hubei,China;2Institute of Tropical and Subtropical Cash Crops,Yunnan Academy of Agricultural Sciences,Baoshan 678000,Yunnan,China)

Abstract:【Objective】The study aimed to investigate the inheritance of some fruit quality traits and to provide a basis for selecting parents in the interploidy cross breeding of citrus.【Methods】Two previously produced triploid hybrid populations derived from the cross of Fallglo mandarin×NS(Nova tangor + Succari sweet orange) and another cross of Kiyomi tangor × SD (Succari sweet orange + Dancy red tangerine)were used as materials.Fully matured fruits were collected in two successive years(2018 and 2019) for fruit quality analysis. For each triploid plant, twelve fruits were collected and pooled for three technical replicates. The transverse diameter, longitudinal diameter and peel thickness were measured using a digital vernier caliper.The fruit weight was determined by a precise 1/100 electronic balance. Furthermore, the soluble solids content and titratable acid content of the fruit pulp were determined using an ATAGO handheld digital refractometer. The genetic variation of the fruit traits was assessed by the coefficient of variation (CV), transmitting ability (Ta) and transgression rate. The normal distribution map was employed to depict the genetic tendencies of the triploid progenies.All data were processed using Microsoft excel.【Results】The distribution of fruit transverse and longitudinal diameter,fruit weight,peel thickness,and soluble solids content frequency in two citrus sexual offspring populations showed a continuous normal distribution, while the distribution of the titratable acid content showed a partial normal distribution. The fruit transverse diameter and fruit quality of the two triploid sexual offsprings were mostly distributed between those of the parents, indicating a trend of intermediate variation.The fruit longitudinal diameter exhibited diverse patterns in different combinations.For instance,60.47%and 42.00%of the fruit longitudinal diameters of individuals from the Fallglo mandarin×NS cross was significantly higher than that of the higher value of the parents in 2018 and, respectively,indicating a genetic trend of transgressive variation.In contrast,94.12%and 97.0%of the fruit longitudinal diameter of the individuals from the Kiyomi tangor × SD combination in 2018 and 2019 fell between the values of the two parents, respectively, showing an intermediate variation trend.The average peel thickness of the fruits was greater than the median value of the parents and most of them were higher than the high-value parents,showing a phenomenon of transgressive inheritance.The ratios of the average value of the soluble solids content of the fruits from the two triploid crosses lower than that of the lower value of the parent were 74.4%and 66.88%,respectively.The average value of the titratable acid content in the fruits of the both two triploid progeny populations was lower than that of the median value of the parents,which was different from the results reported previously,implying that the occurrence rate of the low-acid offspring might be related to the acid content of the female parents.The coefficient of variation for the fruit weight and titratable acid content in the fruit traits exceeded 30%,indicating extensive separation of these traits in the triploid sexual offsprings.In contrast,the coefficient of variation for the fruit transverse and longitudinal diameter,peel thickness,and soluble solids content remained below 30%,implying a limited separation in these traits in the triploid sexual offsprings.The genetic transmission ability of the fruit transverse and longitudinal diameter,peel thickness,soluble solids and titratable acids of the triploid sexual offspring exceeded 70%,suggesting that genetic factors were the primary drivers of variation in these traits.The genetic transmission ability of the fruit weight varied significantly with the different combinations. For instance, the genetic transmitting ability of the fruit weight in the Fallglo mandarin × NS cross for two consecutive years were both high (99.79% and 91.84%).However, the genetic transmitting ability in the Kiyomi tangor × SD combination was relatively low(55.93%and 63.30%),indicating that the inheritance of the fruit weight is greatly influenced by the parents.【Conclusion】The fruit weight,fruit transverse diameter,longitudinal diameter,peel thickness and soluble solids content of the sexual offspring in citrus triploids were polygenic quantitative traits,whereas the titratable acid content might be primarily influenced by a major gene, potentially of paternal origin.Notably,the significant genetic variation was observed in single fruit quality and titratable acid content, facilitating the trait segregation, while the variation was comparatively low in the other traits.The order of the genetic heritability values for several traits was as follows:fruit peel thickness>fruit longitudinal diameter>fruit transverse diameter>titratable acid content>soluble solids content>fruit weight.The enhanced genetic transmission ability were correlated with the prominent heterosis,providing a foundational framework for the parent selection in ploidy hybridization aiming to generate elite triploid progeny in the future.

Key words:Citrus;Triploid hybrid;Interploidy breeding;Fruit character;Genetic tendency

中图分类号:S666

文献标志码:A

文章编号:1009-9980(2024)03-0369-10

DOI:10.13925/j.cnki.gsxb.20230419

收稿日期:2023-10-25

接受日期:2024-01-02

基金项目:国家自然科学基金项目(32172526);云南省科技计划(202102AE090054);湖北省自然科学基金项目(2022CFB158);国家柑橘产业技术体系项目(CARS-26)

作者简介:管书萍,女,在读硕士研究生,研究方向为果树品质生物学。E-mail:gsp954@126.com

*通信作者Author for correspondence.Tel:027-87287393,E-mail:xiekaidong@mail.hzau.edu.cn