猕猴桃新型砧木对金梅猕猴桃果实品质的影响

李大卫,刘小莉,韩 飞,吕海燕,解潇冬,张 琦,田 华,钟彩虹*

(中国科学院武汉植物园,武汉 430074)

摘 要:【目的】利用猕猴桃属丰富的物种资源,研究砧木对接穗品种品质的影响,筛选适合猕猴桃产业应用的新型砧木品种。【方法】首先以大籽等6个长势强旺的猕猴桃物种为供试材料,通过统一嫁接四倍体黄肉猕猴桃品种金梅,精准评测接穗金梅的产量、品质和砧穗间的亲和性。其次,从供试材料中选择3个物种共计10个不同基因型,进一步精准评估不同基因型对接穗品种品质的影响。【结果】团叶、梅叶、对萼和大籽猕猴桃砧木嫁接的金梅平均单果质量均超过100 g,显著高于中华本砧,且大籽等砧木提升了干物质含量等关键内在品质。此外,发现同物种不同基因型同样导致金梅的品质发生较大变异。【结论】大籽621和对萼625等新型砧木能够提升接穗的生长速度、产量和品质,且具有较好的亲和性。值得注意的是,大籽猕猴桃等候选砧木不同基因型个体对接穗品种的影响同样显著,选育适配接穗品种的砧木需要充分考虑从同类型中选择最佳的基因型个体。

关键词:猕猴桃物种;砧木;产量;品质;亲和性;基因型

嫁接是一种重要的营养繁殖手段,最早记载于西汉晚期《氾胜之书》[1-2]。园艺作物嫁接技术历经数千年发展,在现代农业发展中发挥着不可替代的作用。砧木作为承受接穗的载体,不仅影响接穗开花时间、成熟期、产量和品质等重要农艺性状,而且能够发挥抗病免疫、预防虫害、实现果树矮化或乔化等作用[3-4]。砧木和接穗之间的相互作用涉及复杂的生理、生化和分子机制,如砧木的营养和水分传导、砧穗亲和性、植物的生长素和细胞分裂素等激素水平在嫁接过程中发挥了关键调节作用[5];蛋白质、mRNA 和小RNA 在砧木和接穗之间的传导水平也能影响其关键的农艺性状[6-9]

果树中不乏优良砧木使用案例:苹果、梨、柑橘、杧果、杏、葡萄、桃、柿、李、甜樱桃和核桃已经成功选育出多个良种砧木,改良了嫁接品种的长势、抗性、产量与品质[10-11]。然而,一些新兴水果的砧木研究相对滞后。猕猴桃作为一种原产于我国的雌雄异株落叶果树,因其营养成分对健康有利而广受消费者的欢迎。猕猴桃历经近20 a(年)的快速发展已经成为世界主流水果类型;但是世界猕猴桃产业主要依赖于几个有限的砧木类型。新西兰、意大利和智利主要使用美味猕猴桃(Actinidia chinensis var. deliciosa)的实生砧木布鲁诺或者海沃德;中国依赖于米良1 号、秦美及本地野生猕猴桃实生苗。显而易见的是,将整个猕猴桃产业依托于较为狭隘的砧木类型会给整个产业带来巨大风险[12]。近年来,意大利猕猴桃主栽品种因根系排水不良,藤衰退疾病“Moria del kiwi”[13]大量发生;中国猕猴桃园因极端气候导致的内涝和干旱,造成了明显减产和部分毁园。世界猕猴桃产业发达国家开始重视猕猴桃砧木的研发,新西兰的Bounty 71 砧木、日本耐涝的山梨猕猴桃砧木和中国南方普遍使用的水杨桃给猕猴桃砧木育种带来了新的契机。但总体而言,猕猴桃新型砧木的使用和研发尚处于初步阶段,亟待系统评估此类砧木与接穗的亲和性及对接穗品种的品质、产量和抗性的影响。

优质砧木是猕猴桃生产的必要载体,猕猴桃良种砧木选育是维持丰产和稳产的必要环节。中国是猕猴桃的原产地,拥有52个猕猴桃物种及20余个种下分类单元[14],为砧木选育提供了丰富的原始材料。笔者在本研究中利用国家猕猴桃资源圃中丰富的猕猴桃物种材料,通过十余年的精准评价,系统评估了猕猴桃砧木对接穗品种品质的影响并筛选出多个候选的砧木品系,为我国猕猴桃产业的健康和可持续发展提供助力。

1 材料和方法

1.1 材料

供试材料来源于湖北省武汉市国家猕猴桃种质资源圃,通过设计2个试验来筛选砧木品种。首先,基于前期初筛获得的长势旺盛、根系发达的物种材料开展砧木嫁接试验,筛选合适的砧木种。候选砧木材料包括梅叶猕猴桃(A.macrosperma var. mumoides)、团叶猕猴桃(A.glaucophylla var.rotunda)、黑蕊猕猴桃(A.melanandra)、中华猕猴桃复合体(A.chinensis var.chinensis)、对萼猕猴桃(A.valvata)、美味猕猴桃(A.chinensis var.delicisoa)和大籽猕猴桃(A.macrosperma)。其次,在初筛的砧木种中挑选更为优异的基因型,开展砧木的精准鉴定。10份候选材料包括2份中华猕猴桃复合体(中华605和中华610)、1份美味猕猴桃、1份对萼猕猴桃和6份大籽猕猴桃。

本试验开始于2011 年,为保证所有砧木的一致性,采用组培方法获得统一砧木组培苗,经过2 a培育成可供嫁接的苗木。2012 年冬季,接穗统一采用芽接法进行嫁接;嫁接成活的植株于2013 年初开始在国家猕猴桃资源圃7 区品种园开展同园评估试验。为保证试验结果的准确性,嫁接的品种统一采用四倍体黄肉猕猴桃金梅(品种权号:CNA20130340.0),所有的施肥、灌溉、修剪及其他日常管理均保持相对一致。试验株系于2015 年初始挂果,2017年开始进入丰产期。

1.2 方法

1.2.1 砧木及果实表型测定 本研究从2017 年盛果期开始测定,砧木和接穗的亲和性采用直接测量砧穗嫁接口部位上下5 cm 处的周长,评估其是否产生“大小脚”的现象。产量和果实外观品质性状评估在每年10 月上旬开始,果实可溶性固形物含量达到7%以上采收。成熟果实置于猕猴桃工程研究中心常温实验室(20 ℃)软熟,评测常温软熟时间及品质性状。果实形状采用游标卡尺测定,通过计算纵径/横径和横径/侧径来评估猕猴桃的果形指数,其中横径/侧径接近于1代表具有最佳的果形指数。

1.2.2 果实品质测定 每株树至少采集60 个以上果实,分别测量单果质量(采收时测)、软熟期果实可溶性固形物含量、干物质含量、维生素C 含量、硬度等品质性状。测定方法分别如下:单果质量使用电子天平测量且保证精确到小数点后2位。可溶性固形物含量采用ATAGO(PR-32а)折光仪测定,果实从中间横切,取一半果实挤出汁液测定。使用GUSS GS-15水果质地分析仪(GUSS,South Africa)测定果实赤道处的压力硬度,探头直径8 mm,每个果实测2次,测定部位互为90°,单位为N。干物质含量测定方法为干燥称质量法,在果实赤道处切取2~3 mm的果片并称重,在60 ℃下烘干至果实质量恒定,干物质含量为干质量与鲜质量比值。果实中可溶性总糖含量的测定参考NY/T 2742—2015《水果及制品可溶性糖的测定3,5-二硝基水杨酸比色法》,以葡萄糖折算可溶性总糖含量(w,后同),单位为%;果实中维生素C 含量的测定参考GB 5009.86—2016《食品安全国家标准食品中抗坏血酸的测定》中的2,6-二氯靛酚滴定法,使用自动滴定仪(HI931,Hanna)滴定,以鲜质量计,单位为mg·kg-1

1.3 数据处理

所有的测定数据均具有3 个以上的重复;数据总结采用Excel 2020。数据统计分析采用SPSS 21.0(IBM SPSS Statistics,New York,USA),结果以平均值±标准差表示;显著性统计分析采用Tukey检验(0.05 水平)。研究数据的画图采用GraphPad Prism 9.0 软件(GraphPad Software, San Diego, CA,USA)。

2 结果与分析

2.1 不同猕猴桃物种砧木对金梅外观品质的影响

外观品质是猕猴桃重要的商品性状,是吸引消费者购买的外在指标。笔者在本研究中对不同砧木嫁接的黄肉猕猴桃品种金梅的果肉颜色、大小和其他性状开展了多重分析。从图1-A 可见,金梅猕猴桃果实呈椭圆形,整体呈现金黄色果肉,具有优良的果肉颜色商品性状(图1-A、C)。分析不同砧木嫁接的金梅猕猴桃,发现果实大小存在差异,其中团叶、梅叶、对萼和大籽的砧木平均单果质量均高于100 g,但中华砧木平均单果质量仅96.69 g(图1-B)。进一步分析果形指数发现,对萼和中华砧木具有最大的纵径/横径以及最小的横径/侧径(图1-D),证明这2种砧木的果实多呈现长椭圆形,果实最为整齐。值得注意的是,小提琴图显示大籽和黑蕊砧木的果形指数出现部分偏离,证明在这2 种砧木中可能出现部分的畸形果。

图1 不同砧木对金梅猕猴桃外观品质的影响
Fig.1 Effect of different rootstocks on exterior quality of Jinmei Kiwifruit

图中符号代表样本数量。下同。
The symbol represent the number of samples.The same below.

2.2 不同猕猴桃砧木对金梅内在品质的影响

果实的内在品质决定了贮藏期、风味、营养,是猕猴桃最重要的性状。如表1 所示,不同猕猴桃种类作砧木的果实常温软熟时间基本相近,均在19~20 d,其软熟时期的硬度在0.244~0.449 N。然而,果实的可溶性固形物和干物质含量存在一定变异,其中大籽、黑蕊和对萼砧木嫁接的金梅猕猴桃具有较高的可溶性固形物含量(16.07%~16.71%)和干物质含量(17.39%~18.18%),大籽砧木显著高于中华猕猴桃砧木(15.57%,16.98%)。

表1 不同猕猴桃物种砧木对金梅猕猴桃内在品质的影响
Table 1 Effects of rootstock of different kiwifruit species on intrinsic quality of Jinmei Kiwifruit

注:表中同列不同小写字母表示各处理间差异显著(p<0.05)。
Note:Different small letters in the same column indicate significant differences among different treatments at 0.05 level.

砧木种类Rootstocks types黑蕊砧木A.melanandra团叶砧木A.rotunda中华砧木A.chinensis大籽砧木A.macrosperma梅叶砧木A.mumoides对萼砧木A.valvata软熟时硬度Firmness of soft ripening/N 0.264±0.132 bc 0.449±0.244 a 0.321±0.243 abc 0.403±0.256 ab 0.244±0.152 c 0.306±0.169 abc常温软熟时间Time taken for fruit to ripen under room temperature/d 20.13±1.01 a 19.00±0.00 c 19.87±1.01 ab 19.40±0.81 bc 19.77±1.14 ab 19.00±0.00 c w(可溶性固形物)Soluble solid content/%16.07±1.30 ab 15.84±1.17 b 15.57±1.00 b 16.71±0.98 a 15.54±1.05 b 16.22±0.77 ab w(干物质)Dry matter content/%17.39±1.35 bc 17.10±1.10 c 16.98±1.18 c 18.18±0.92 a 16.95±1.00 c 17.70±0.91 bc

2.3 不同猕猴桃种类与金梅接穗的亲和性

砧木和接穗因来源不同常出现嫁接不亲和现象。在嫁接后第5 年分别测定砧木、嫁接口和接穗的周长并计算直径大小。结果表明大籽和对萼砧木的平均直径均超过7 cm,具有明显更强旺的长势;同时,嫁接在大籽和对萼上的接穗相较于传统的中华本砧也具有更粗壮的直径(图2-A)。但是,梅叶猕猴桃嫁接后出现明显的嫁接口膨大现象,而中华猕猴桃嫁接口较小。进一步分析发现团叶和梅叶的接穗和砧木直径部分比值超过1(图2-B),这暗示出现了明显的“大小脚”现象,且这2个砧木的嫁接口和砧木直径比值最高超过1.5(图2-C),同样出现了嫁接口类似“肿瘤”样的不亲和现象。

图2 猕猴桃砧木、接穗和嫁接口茎粗比较分析
Fig.2 Comparative analysis of the kiwifruit stem diameter of rootstocks,scions and grafting unions

2.4 猕猴桃不同基因型砧木对嫁接品种的品质影响

笔者在本研究中选取了10 个不同基因型的砧木类型,通过评估接穗品种金梅的软熟期硬度、干物质、维生素C 和可溶性糖含量以分析不同基因型的砧木对关键品质性状的影响。不同基因型砧木嫁接后金梅软熟期硬度较为平均(图3-A),其中大籽629 砧木具有最高的硬度。以大籽猕猴桃为例,基因型621 的干物质含量(17.08%)比627(15.36%)高10%以上(图3-B);基因型626 的维生素C 含量(942.21 mg·kg-1)比基因型621(701.57 mg·kg-1)高25.53%(图3-C)。在风味品质方面,美味猕猴桃ML1、大籽621 和大籽619 具有较高的可溶性糖含量,明显高于大籽629(图3-D)。可见,砧木的不同基因型对接穗品种的果实品质性状具有显著的影响。

图3 猕猴桃不同基因型砧木对金梅品种品质的影响
Fig.3 Effects of different rootstock genotypes on the fruit quality of Jinmei kiwifruit

笔者在本研究中进一步调查了不同基因型砧穗之间的亲和性(图4),中华猕猴桃605和610具有最佳的亲和性,其砧穗粗度基本一致,且嫁接口平滑一致。此外,大籽和对萼不同基因型嫁接中华品种金梅后,整体亲和性较好;同时,研究发现因这2 种砧木长势更旺盛,形成了砧木稍大于接穗的类型。然而值得注意的是,在众多基因型中发现了明显的小脚现象,即砧木的生长显著慢于接穗,这导致植株后期出现明显的生长缓慢,产量低的现象。综合考虑上述不同砧木对金梅品种的品质和嫁接亲和性,笔者发现对萼625和大籽621具有最佳的综合表型,后续命名为中科猕砧1号和中科猕砧2号砧木,目前已申请新品种保护并在全国6个省(市)开展大规模中试及推广应用。

图4 猕猴桃不同基因型砧木嫁接金梅品种的亲和性
Fig.4 Compatibility of Jinmei kiwifruit grafted on different Kiwifruit rootstocks

3 讨 论

改革开放以来,中国果树产业取得了飞速的进步,大量优异品种的育成加速了产业的革新。据统计,在近40 年间,柑橘、苹果等11 种果树共选育出1968 个品种(系),但砧木品种(系)仅43 个,占比不足2.2%[15]。特别是砧木育种主要集中于苹果、葡萄、桃等几个大树种。例如,苹果矮化砧木中砧一号和青砧一号具有良好的矮化潜力[16]。近20 年中国猕猴桃产业发展迅猛,连续10年收获面积及年产量均稳居世界第一,已经成为中国第九大水果类型。但是,中国猕猴桃平均单产极低,666.7 m2产量仅800 kg,是新西兰的32.17%[17];中国猕猴桃的生产技术和产业还存在巨大的提升空间。相对于接穗品种(超过150 个)的快速发展,目前世界猕猴桃产业95%以上接穗依赖美味猕猴桃的几个实生砧木,主要是米良1 号、秦美、布鲁诺、海沃德和野生猕猴桃种子播种出的实生苗,急需拓展猕猴桃的砧木研究。本研究初步探讨了多个猕猴桃物种和基因型砧木对中华品种的品质影响,为未来新型砧木选育奠定了基础。

砧木与接穗亲和力是嫁接首要考虑的问题。在大型木本和藤本植物中,主要的不亲和类型包括易位嫁接不亲和(translocated graft incompatibility)和局部嫁接不亲和(localized graft incompatibility)[18-19],前一种类型通常在嫁接后的第1年出现,表现为生长停止,落叶,叶片变色甚至死亡;而后一种情况涉及发育后期的轻微和延迟的不亲和性。前期研究表明,猕猴桃接穗和砧木的亲缘关系越远,其一年内的易位嫁接亲和力越差[18];例如净果组的软枣、大籽、对萼和葛枣等猕猴桃类型嫁接后1 年内的成活率显著低于传统的本砧嫁接(中华猕猴桃复合体)[21-24]。笔者通过近10年观察发现,局部嫁接不亲和同样存在猕猴桃砧木和接穗之间,其中典型的表现为“大小脚”现象。在黑蕊猕猴桃、葛枣和软枣猕猴桃等类型中发现有“上大下小”的现象,而在大籽猕猴桃和对萼猕猴桃等生长极其旺盛的砧木中存在“上小下大”的情况。在本研究中,笔者发现金梅品种与大籽系列砧木具有较好的亲和性,不存在特别明显的嫁接不亲和现象,能够满足产业化的需求。

砧木对接穗品种性状的影响已经被广泛证明[12]。前期研究发现中华猕猴桃品种桂海4号砧木能够影响美味猕猴桃实美的平均产量[25];大籽猕猴桃能够增加布鲁诺品种25%以上的单果质量和产量[26];对萼猕猴桃砧木能够显著增加红阳猕猴桃的平均单果质量和结果数量[27]。在本研究中,与传统的中华和美味本砧相比,大籽、对萼、团叶和梅叶等猕猴桃物种砧木能够促进金梅的长势,特别是大籽和对萼猕猴桃在嫁接5年后,砧木直径超过8 cm、接穗直径超过6 cm;而且接穗品种的平均单果质量高于本砧品种,说明新型砧木在提升现有品种的产量方面具有较大潜力。此外,前期研究表明不同砧木对接穗叶片和果实的营养元素的积累具有重要影响,低活力砧木导致接穗营养元素的积累较少[28];且猕猴桃的砧木和接穗同时影响果实中糖及有机酸含量、采收期和后熟期[29]。笔者在本研究中同样发现大籽猕猴桃砧木嫁接金梅品种后,金梅果实具有较高的干物质含量,且通过筛选不同基因型的大籽猕猴桃,发掘出能够明显提升维生素C 及可溶性糖含量的种质,这为未来金梅特有砧木的品种选择提供了直接参考。

猕猴桃属植物适宜生长在温暖湿润、阳光充足且土壤偏酸性的环境中。近年来,随着产业化区域的扩大,南至云南和广西、北至陕西和山东均有大量中华和美味猕猴桃品种种植。猕猴桃种植区域的扩大带来许多的产业问题,如干旱、水涝、盐碱、土壤贫瘠等已经严重干扰了猕猴桃产业的健康发展,新的砧木的选育有望改变这一困境。目前在传统美味猕猴桃砧木的基础上,我国南方出现了水杨桃这一类型的砧木。笔者调查发现市场上流通的水杨桃包括大籽、对萼和葛枣,甚至还有软枣、狗枣和京梨等多种类型。尽管笔者在本研究中发现相对于本砧,大籽和对萼猕猴桃对金梅的品质和产量均有正向的促进作用,但是值得注意的是,同一类型物种砧木因其基因型不同,对接穗品种的品质影响存在显著差异。因此,需要正视目前产业中所谓的水杨桃砧木存在多个猕猴桃物种混杂或同一个物种多种基因型混杂的问题。历经十余年,笔者发现砧木对接穗具有诸多影响,深认为砧木和接穗的互配必须基于长期的观察及了解两者的生长特征。最后,本研究发掘的大籽和对萼猕猴桃优良砧木因其长势强旺,对果实的形状、枝条生长、挂果荷载、品质均造成了显著影响,因此在种植过程中需要优化现有的种植密度、施肥方式、修剪、环割等技术方案。

4 结 论

大籽猕猴桃和对萼猕猴桃适于作中华猕猴桃四倍体金梅的砧木;同一种类中不同基因型的砧木对接穗品种的性状存在巨大影响。

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Effect of new rootstocks on the fruit quality in Jinmei kiwifruit

LI Dawei, LIU Xiaoli, HAN Fei, LÜ Haiyan, XIE Xiaodong, ZHANG Qi, TIAN Hua, ZHONG Caihong*

(Wuhan Botanical Garden,Chinese Academy of Sciences,Wuhan 430074,Hubei,China)

Abstract: 【Objective】Kiwifruit is a deciduous fruit tree crop whose fruits are rich in nutrients and very popular with consumers.With its rapid development over the past two decades, kiwifruit has become the world’s most dominant fruit.However, the current world kiwifruit industry relies on a few rootstock varieties from seedlings of the Actinidia chinensis var.delicious.The kiwifruit industry is potentially at risk due to the narrow genetic diversity of rootstocks,and it is of great economic value to explore new rootstocks.Actinidia (kiwifruit) species are native to China, which provides rich germplasm resources for rootstock selections.Here, we used kiwifruit species from the National Actinidia Germplasm Repository in China to evaluate rootstock's effect on the fruit quality,so as to screen out new rootstock varieties.【Methods】In this study, two assays were designed to screen new rootstock varieties.Firstly, grafting experiments were conducted, applying six candidate Actinidia species with a vigorous root system, including A.macrosperma var. mumoides,A.glaucophylla var. rotunda,A.melanandra,A.chinensis Planch,A.valvata Dunn and A.macrosperma C.F.Liang.Secondly, ten kiwifruit genotypes were further selected based on the results of grafting experiments to determine their effect on the fruit quality of the scion cultivar (Jinmei).To obtain unified rootstock seedlings, tissue culture propagation was adopted to ensure the consistency of experimental materials.The compatibility between rootstock and scion was evaluated by measuring the stem diameter of rootstock as well as scion and grafting union after five years of grafting.Various quality indexes were measured among grafting lines to analyze the impact of rootstocks on scion cultivar, including mean fruit weight, soluble solids content, dry matter content,vitamin C content and fruit firmness.In all experiments,more than three replicates were conducted,with each measuring more than 60 fruits.【Results】A total of four conclusions were drawn.(1) The rootstock of different kiwifruit species affected the exterior quality of Jinmei kiwifruit.Jinmei grafted on different rootstocks showed different fruit sizes.The fruit weight exceeded over 100 grams when grafted on A.mumoides,A.rotunda,A.macrosperma and A.valvata rootstocks,while it was only 96.69 grams on A.chinensis rootstock.The analysis of the fruit shape index showed that stion combinations of Jinmei with A.valvata and A.chinensis produced long oval and neat fruit.In contrast,it had partially deviated fruit when grafted on A.macrosperma and A.melanandra rootstocks.(2)Intrinsic quality of Jinmei kiwifruits was affected by different rootstocks.The DFR (Days taken for fruit to ripen at room temperature) were 19-20 days and firmness of Jinmei kiwifruit was between 0.244-0.449 N among different stion combinations.In addition, the contents of soluble solids and dry matter in fruits varied.The Jinmei kiwifruit grafted on A.macrosperma,A.melanandra and A.valvata rootstocks had the highest soluble solids content (16.07%-16.71%) and dry matter content (17.39%-18.18%), which was significantly higher than that on A.chinensis rootstocks(15.57%,16.98%).(3)The different compatibility existed between various stion combinations.The average stem diameter of both A.macrosperma and A.valvata rootstocks and scions was more than 6.3 cm, showing vigorous growth between these combinations.However,the grafting union of kiwifruit with A.mumoides appeared to be an apparent enlargement,while those on A.chinensis rootstock were the smallest.Further analysis showed that the ratio of scion to rootstock diameter was more than 1,suggesting an obvious grafting incompatibility(commonly called‘small foot’)between the“Jinmei”scion,and A.mumoides and A.rotunda rootstocks.(4)The different genotypes of rootstock significantly influenced the quality characteristics of scion varieties.The fruit firmness of Jinmei at the ripening stage was relatively average among various rootstock genotypes, while the fruit on A.macrosperma 629 rootstock had the highest firmness.The contents of soluble solids, vitamin C and soluble sugar of Jinmei grafted on different genotypes of rootstocks were significantly different.Taking different rootstock genotypes of A.macrosperma as an example, the dry matter content of genotype A.macrosperma 621 (17.08%) was over 10% higher than that on A.macrosperma 627(15.36%).Genotype A.macrosperma 626 had 25.53%vitamin C content(942.21 mg·kg-1)higher than genotype A.macrosperma 621(701.57 mg·kg-1).In terms of flavor quality,the fruit on A.deliciosa ML1, A.macrosperma 621 and A.macrosperma 619 had the highest soluble sugar content,which was significantly higher than that on A.macrosperma 629.【Conclusion】This study examined the impact of different rootstocks of kiwifruit species and genotypes on scion varieties.Compared with traditional A.delicious rootstocks, A.mumoides, A.rotunda, A.macrosperma and A.valvata rootstocks could improve the plant vegetative growth and fruit size of Jinmei, indicating that the new rootstocks had greater potential to increase the yield of kiwifruit.In addition, the scion cultivar Jinmei had good compatibility with the A.macrosperma rootstocks.Finally, a significant increase in dry matter, vitamin C and soluble sugar contents was observed in Jinmei kiwifruit when various genotypes of A.macrosperma rootstock were utilized.New rootstocks,such as A.macrosperma 629 and A.valvata 625 were identified, which will be used for the commercialization of Jinmei to increase its yields and fruit quality.This research will be used to develop new rootstocks for the future production of kiwifruit.

Key words: Actinidia species;Rootstock;Yield;Quality;Compatibility;Genotype

中图分类号:S663.4

文献标志码:A

文章编号:1009-9980(2023)10-2160-10

DOI:10.13925/j.cnki.gsxb.20220633

收稿日期:2022-11-16

接受日期:2023-05-26

基金项目:湖北省重点研发计划项目(2021BBA100);湖北省科技重大专项(2021AFB002);中国科学院科技扶贫项目(KFJ-FP-202101);长江猕猴桃产业技术研究中心开发课题(CJZX20210103)

作者简介:李大卫,男,研究员,研究方向为猕猴桃资源与生理。Tel:18672330536,E-mail:lidawei@wbgcas.cn

*通信作者Author for correspondence.Tel:13407147939,E-mail:zhongch@wbgcas.cn