留树保鲜对恭城水柿果实品质、贮藏特性及翌年果实产量和品质的影响

杨 旭1,林 清2,黄 丽2,刘翠玉1,徐 阳1,吴开云1,龚榜初1*

1中国林业科学研究院亚热带林业研究所,杭州 311400;2恭城瑶族自治县农业农村局,广西 恭城 542500)

摘 要:【目的】探讨激素和叶面肥喷施对留树保鲜水柿的果实品质、贮藏特性及翌年产量和品质的影响,为水柿果实留树保鲜提供理论依据和技术指导。【方法】在花后170~214 d每隔7~15 d分别喷施75%的GΑ3 50 000倍液、0.01%2,4表芸薹素内酯2800倍液及可溶性叶面肥800倍液3次(处理Ⅰ)、4次(处理Ⅱ)和5次(处理Ⅲ),同时增施0.5%的尿素和0.5%磷酸二氢钾作为追肥,以成熟后自然挂果、不增加追肥量的植株作为对照,比较不同处理对不同采摘时间果实的色泽、营养成分含量、果实质地及贮藏特性的影响,并探讨留树保鲜措施对翌年果实产量和品质的影响。【结果】激素和叶面肥喷施导致果实色泽转变和营养成分转化延迟,减缓水柿硬度、弹性、内聚性、咀嚼性的下降,且处理组的果实在贮藏期营养成分含量和质地的下降相比对照组更缓慢,其中喷施混合液3次(处理Ⅰ)的延缓效果更为显著。同时与对照组相比,处理组延迟采收后植株翌年的果实产量、果实大小和优质果率并无显著差异。【结论】留树保鲜技术能有效延迟水柿果实的成熟,且不会对果实品质、贮藏特性和翌年的产量、品质造成影响。因此,在近成熟期喷施3 次GΑ3、表芸薹素内酯和可溶性叶面肥是水柿留树保鲜最经济有效的方案。

关键词:水柿;留树保鲜;果实品质;贮藏特性;翌年产量品质

柿为我国广泛种植的大宗水果,种植面积和产量均位居世界首位[1]。广西壮族自治区恭城瑶族自治县(简称“恭城县”)是我国涩柿的主要产地,年产量约占全国总产量的1/5。目前恭城县的主栽品种是鲜食、加工兼用的水柿,已有400多年的种植和加工历史。2019—2022年期间,恭城的水柿产业从栽培面积到产量、产值等各方面均有了显著的提升:栽培面积由1.29 万hm2 增加到1.52 万hm2,增长17.80%;产量由55.80 万t 增加到78.34 万t,增长40.45%;柿综合产值由5.99 亿元增加到9.95 亿元,增长66.08%;全县柿农人均可支配收入从19 245元增加到22 206 元,增加了15.39%(恭城县农业农村局2022年统计数据)。

但恭城县的柿产业也存在较大的问题,主要是种植品种单一,柿果集中在10—12 月成熟,大部分柿果通过鲜果运销和消费,由于上市时间过于集中,贮藏加工与销售压力巨大。柿果在贮存后期有呼吸峰出现,造成果实快速软化和腐烂变质[2]。贮藏过程中易感染黑曲霉、白腐霉、交链孢霉等真菌及细菌病害而变软变质[3]并发生贮藏期冷害,造成果面灰暗、水渍状,果肉不能正常后熟软化[4]。因此寻求低成本、高效节能、安全的贮藏保鲜技术显得尤为重要。留树保鲜是在果实即将进入或已进入成熟期后,通过一定的技术处理,延缓果实成熟过程,继续留在树体上,达到延迟采收的目的。该技术具有成本低、避免保鲜药物残留、进一步改善品质和增加产量等优点,对延长果实供应期有着重要的作用,在椪柑[5]、苹果[6]、杧果[7]、樱桃[8]等果树上已取得了较好的效果。

目前已有部分研究通过喷施赤霉素对柿属植物进行留树保鲜[9-11],但由于赤霉素的浓度不合适或者喷施时间不正确,也没有采取更多的其他措施(如保叶、保树势),留树保鲜效果并不理想,主要表现为落叶早(11 月上下旬)、果实软化快(12 月上中旬)、不能再用于脆柿加工,或由于赤霉素使用浓度过大、喷施过迟,影响树体花芽分化而造成来年开花减少。鉴于此,有必要提供一种科学有效的柿留树保鲜的方法,来延缓果实的成熟软化,并探讨柿果在留树和贮藏期间的品质变化规律,旨在为水柿果实留树保鲜提供理论依据和技术指导。

1 材料和方法

1.1 试验地概况

试验地位于广西壮族自治区恭城县莲花镇(110°52′47″ E,24°43′48″ N)。该镇地处广西东北部,属亚热带季风气候,年均温为18.2 ℃,年降雨量1 668.5 mm,年日照时数1 872.3 h,全年无霜期在300 d 以上。供试土壤为红黄壤,主要成分为黏土,土层深厚。对土壤理化性质进行检测表明土壤偏酸性,pH 4.90~6.12,土壤有机质含量(w,后同)18.33~36.90 g·kg-1。土壤全氮含量1.14~1.98 g·kg-1、全磷含量0.81~1.33 g·kg-1、全钾含量7.07~13.90 g·kg-1,属中等肥力土壤。

1.2 试验方法

1.2.1 药剂处理方法 留树保鲜试验于2021 年9月至2022 年1 月进行,试验材料为当地主栽品种水柿。选择生长一致的盛果期水柿,栽培株行距为4 m×5 m。试验共设3 个处理,在果实着色期喷施GΑ3 50 000 倍液(上海第十八制药厂,GΑ3纯度为75%)、2,4表芸薹素内酯乳油2800倍液(河南勇冠乔迪农业科技有限公司,2,4表芸薹素内酯含量0.01%),及可溶性叶面肥800倍液,施用量为150 L·hm-2。叶面肥中N 含量为12%,P 含量为12%,Ca 含量为10%,B 含量为2%。重点喷施果蒂部位,前期每隔15 d 喷施一次,后期果实成熟时每隔7 d 喷施1 次。具体喷施次数和日期见表1[10]。同时增加追肥量,在果实采摘后至叶片脱落前叶面喷施0.5%的尿素和0.5%的磷酸二氢钾作为追肥。试验采取完全随机区组设计,单株小区,每处理10 株。另选择10 个单株喷施清水(喷施时间见表1),不增加追肥量作为对照。

表1 药剂处理次数与喷施时间
Table 1 Spraying time and date of hormone treatments

处理Treatment对照Control喷施时间4 Spraying date 4花后207 d 207 days after anthesis喷施时间5 Spraying date 5花后214 d 214 days after anthesisⅠⅡⅢ喷施时间1 Spraying date 1花后170 d 170 days after anthesis花后170 d 170 days after anthesis花后170 d 170 days after anthesis花后170 d 170 days after anthesis喷施时间2 Spraying date 2花后185 d 185 days after anthesis花后185 d 185 days after anthesis花后185 d 185 days after anthesis花后185 d 185 days after anthesis喷施时间3 Spraying date 3花后201 d 201 days after anthesis花后201 d 201 days after anthesis花后201 d 201 days after anthesis花后201 d 201 days after anthesis花后207 d 207 days after anthesis花后207 d 207 days after anthesis花后214 d 214 days after anthesis

1.2.2 采样方法 对照处理从水柿果实开始转色时(花后190 d)开始取样,此后每15 d 取样一次,直至花后234 d 取样结束。处理Ⅰ从花后220 d 开始取样,处理Ⅱ花后234 d开始取样,处理Ⅲ从花后250 d开始取样,每15 d 取样一次,直至花后294 d 取样结束。

每次采样时从树冠中部外围东、西、南、北4 个方向随机选取大小和成熟度一致的果实样品,每个植株采集3个合计30个进行果实外观性状、营养成分含量及贮藏性状的测定。

1.2.3 果实性状分析(1)不同采样时间果实色泽分析。果实色泽用美能达色差计CR-400进行测定,采用“Hunter Lab”表色系统测定a 值、b 值、L 值。L值从小到大表示果实的亮度和对比度增加,a 值从小到大表示果实从深绿到红色的转变,b 值从小到大指果实颜色从亮蓝色到焦黄色的转变;色度值C=(a2+b21/2

(2)不同采样时间果实营养成分分析。每次采样后,各处理随机选取10 个果实,混合取样后用紫外分光光度法测定果实中类胡萝卜素含量[12],用高效液相色谱法测定抗坏血酸含量[13],用铜还原碘量法测定可溶性糖含量[14],用酸碱指示剂滴定法测定可滴定酸含量[15]

(3)不同采样时间果实质构分析。采样后,去除各处理水柿果皮,选择赤道部位果肉,切成20 mm×20 mm×20 mm 的方块,使用P/75 探头进行质地多面分析试验(TPΑ),由质地特征曲线得到水柿果实硬度、内聚性、弹性和咀嚼性等质构指标。测试参数:测试速率60 mm·min-1,触发力0.3 N,感应元量程1000 N,上升高度20 mm,果肉压缩比15%。每处理随机选取10个果实进行重复测试,测定结果取平均值[16]

(4)果实贮藏性状分析。为保证果实质地的一致性,每个处理从果实开始转色时自植株的树冠中部外围东、西、南、北4个方向随机选取共100个果实进行果实贮藏性状的分析。每个处理分别于花后190、220、235、250 d 采样,分别置于4 ℃冰箱中冷藏。每隔15 d 从中随机选取10 个果实用于果实营养成分和质地的测定,测定方法同(2)和(3)。

1.2.4 留树保鲜对水柿产量和果实品质的影响 于2022年9月果实即将成熟时对不同处理植株的果实数量进行统计,同时在每个处理树冠的东、南、西、北4 个方向随机选取50 个果实,测量果实纵横径及单果质量,统计各处理的优质果率(其中特级果>190 g,一级果160~190 g,二级果<160 g),计算各处理的单株产量和预计每666.7 m2产量,以上试验每个处理3次重复。

1.3 数据分析

数据分析采用SPSS Statistics 25.0 进行差异显著性分析,绘图使用Excle 2019完成。

2 结果与分析

2.1 留树保鲜对不同采样期水柿果实色泽的影响

柿的近成熟期主要完成内含物质的转化和色素的积累。不同处理对水柿果实色泽的影响见图1。水柿果实L 值随着生长时间的延长无规律性变化,且各处理间无显著差异。随着生长时间的增加,果实abc 的值逐渐增大,不同处理果实色泽的变化趋势与对照相似,仅将色泽的变化推迟了30 d左右,且处理Ⅰ、Ⅱ、Ⅲ间无显著差异,表明留树保鲜处理可推迟果实色泽各指标值的增大。

图1 不同处理对水柿果实色泽的影响
Fig.1 Effect on persimmon fruit colour of different treatments

2.2 留树保鲜对不同采样期水柿果实营养物质的影响

不同处理对水柿果实中营养物质含量的影响见图2。随着生长时间的延长,除抗坏血酸含量呈现先上升后下降的倒“Ⅴ”字的变化趋势外,果实中类胡萝卜素、可溶性糖、可滴定酸含量呈逐渐上升的趋势。留树保鲜处理后,抗坏血酸峰值的出现比对照晚15~30 d,胡萝卜素、可溶性糖、可滴定酸含量上升趋势线斜率低于对照,表明留树保鲜技术可减缓果实中营养物质的积累。

图2 不同处理对水柿果实营养物质含量的影响
Fig.2 Effect on the nutrient content of persimmon fruit of different treatments

2.3 留树保鲜对不同采样期水柿质地的影响

果肉硬度是果肉抗压能力强弱的体现,与原果胶含量有关;弹性反映果肉经第一次压缩变形后,去除挤压力所能恢复的程度;内聚性是咀嚼果肉时,为保持果肉完整性和果粒紧密连接抵抗受损的能力,反映了果实细胞间结合力的大小;咀嚼性是果实硬度、弹性、内聚性的乘积,反映了咀嚼时果实的抵抗性,进而反映了果实的新鲜程度。以上指标是评价柿果肉质地特性的重要指标。不同处理对水柿质地的影响见图3。水柿硬度、弹性、内聚性、咀嚼性随成熟度的增加呈逐步下降的趋势,处理Ⅰ和处理Ⅱ的趋势线斜率显著低于对照,表明这两种处理可减缓水柿质地的变化,其中以处理Ⅰ的减缓程度较为显著。处理Ⅲ的各质构数据趋势线斜率与对照相近,表明其对水柿质地的变化无显著的影响,但能延迟水柿果实的成熟。

图3 不同处理对水柿质地的影响
Fig.3 Effect on persimmon fruit texture of different treatments

2.4 留树保鲜对不同贮藏期水柿营养成分和质地的影响

贮藏期间,水柿的类胡萝卜素和可溶糖含量呈现先上升后下降的趋势,这是由于水柿在贮藏过程中果实内部大分子内含物逐渐降解,导致类胡萝卜素和可溶性糖含量的不同程度上升(图4)。其中对照和处理Ⅲ的类胡萝卜素含量的峰值在贮藏后30 d 左右出现,处理Ⅰ和处理Ⅱ的峰值在贮藏后45 d 左右出现;各处理果实中可溶性糖含量的峰值均出现在贮藏后30 d 左右,此后呈急剧下降的趋势,其中处理Ⅰ的下降幅度显著低于对照和其他处理;由于呼吸作用和蒸腾作用,水柿果实中抗坏血酸和可滴定酸含量随着贮藏时间的增加而降低,激素处理可减缓其下降,其中处理Ⅰ的减缓作用最为显著。

图4 不同处理对水柿贮藏果实品质的影响
Fig.4 Effect on nutrient content of persimmon fruit of different treatments during storage period

随着贮藏时间的增加,水柿果肉硬度、弹性、内聚性、咀嚼性等指标也会发生相应的变化,不同留树保鲜处理对果肉质地影响程度有一定的差别,图5是不同处理水柿贮藏期果肉质地的变化情况。水柿果肉的硬度、弹性、内聚性和咀嚼性均随着贮藏时间的延长而下降。贮藏结束时,各处理除果肉内聚性稍低于对照外,果肉的硬度、弹性和咀嚼性分别比对照提高了12.47%~24.72%、5.91%~7.53%和17.83%~43.55%,表明激素处理可抑制细胞壁中原果胶的降解从而减缓果实的软化。不同处理贮藏期营养成分和质构指标的分析结果显示,处理Ⅰ可显著减缓营养物质和质地的变化,与对照相比,可将水柿果实的贮藏期由60 d 延长至75 d,处理Ⅱ和处理Ⅲ对水柿果实的贮藏特性无显著影响。

图5 不同处理对水柿贮藏期果实质地的影响
Fig.5 Effect on persimmon fruit texture of different treatments during storage period

2.5 不同处理对水柿翌年产量和果实品质的影响

如表2 所示,2022 年对照水柿植株单株产量在100.83 kg,每666.7 m2产量为3 327.48 kg,3 种处理的单株产量范围在99.52~100.36 kg,每666.7 m2产量范围在3 284.22~3 311.88 kg。对比对照,各处理的产量稍有下降,但处理间差异未达到显著性,表明留树保鲜不会造成水柿产量的显著降低。对照水柿的果实横径和纵径分别为7.54 cm 和4.99 cm,单果质量为198.94 g,3 种处理后果实横径和纵径范围在7.52~7.55 cm 和4.96~5.00 cm,单果质量为197.12~198.36 g,各处理间差异未达到显著水平,同时各处理和对照的优质果率也没有显著差别,表明留树保鲜不会造成翌年果实品质的下降。

表2 不同处理对水柿翌年产量和果实品质的影响
Table 2 Effect on persimmon yield and fruit quality in the next year of different treatments

注:同列相同小写字母表示差异不显著(p>0.05)。
Note:The data with small capital letters in same column show no significant difference(p>0.05).

二Small-sized率果级fruit rate/%15.63±4.66a 14.62±3.30a 14.10±2.82a 14.82±2.57a一Medium-sized率果级fruit rate/%30.07±4.91a 29.43±4.09a 30.94±3.95a 30.82±3.29a率特Extra gradequality果级fruit rate/%54.30±5.78a 55.95±6.38a 54.96±6.62a 54.35±6.81a量产Predicted output/3 311.88±646.97a 3 288.27±619.10a 3 284.22±625.81a 3 327.48±636.41a(kg·666.7 m-2)量产株单Yield perplant/kg 100.36±20.56a 99.64±18.49 a 99.52±19.61 a 100.83±19.47a数果结株单Numberof fruit per plant 505.95±89.57a 504.30±92.51a 504.88±75.75a 506.85±73.62a单Fruit mass/g量质果198.36±38.38a 197.59±33.65a 197.12±30.07a 198.94±30.27a果Fruit longitudinal径纵实length/cm 4.97±0.76 a 5.00±0.75 a 4.96±0.73 a 4.99±0.78 a果Fruit transverse径横实length/cm 7.55±1.48 a 7.52±1.47 a 7.53±1.34 a 7.54±1.29 a处Treatment理照ⅠⅡⅢ对Control

恭城现有留树保鲜的水柿总面积共计约133.33 hm2。留树保鲜可连年进行,不需要轮换。笔者对其中的28户农户进行了走访调查,每户农户进行留树保鲜的面积在666.7~2 000.1 m2不等。以在农户中推广最为普遍的喷施3次药剂为例,据统计,2019—2021年,未留树保鲜的盛果期水柿园平均每666.7 m2产量分别为(3 338.17±358.21)kg、(3 305.98±298.65)kg、(3 315.28±457.14)kg,而留树保鲜水柿园平均每666.7 m2产量分别为(3 325.37±447.68)kg、(3 291.43±468.52)kg、(3 313.12±522.15)kg,各年份间及同一年份留树保鲜与对照间差异均不显著,也不存在明显的大小年现象,进一步表明留树保鲜技术不会对水柿产量造成大的影响。

3 讨 论

大量农户的实践结果表明,留树保鲜技术不会造成柿果产量和品质的下降。本文植物激素对2021年柿果品质、贮藏特性影响的研究结果是柿果留树保鲜成效的科学验证。赤霉素(GΑ)是一类调节生长发育的植物激素,叶面喷施能有效地抑制柿果实的膨大生长、着色、糖的积累及果肉软化[9]。果实成熟过程中颜色的转变主要与叶绿素的降解及其他色素,如花青素和类胡萝卜素的积累有关[17]。GΑ3对柿果着色的影响主要是通过抑制果皮中叶绿素的分解和类胡萝卜素的积累造成的[11];其次,果实成熟时细胞壁的降解是果实软化的直接原因,其降解是由一系列酶的催化作用产生的[18]。柿果实在成熟过程中,随着留树时间的延长,柿果中果胶酶和多酚氧化酶含量上升,柿软化和褐变速率加快,果实品质下降[19]。这可能是由于外源GΑ3使得柿果中内源赤霉素活性升高[11],半乳糖苷酶(β-Gal酶)活性的升高,延缓纤维素和原果胶降解以及水溶性果胶含量增加,阻碍了果实的软化进程[20];外源GΑ3还参与了果实发育过程中营养物质的积累与代谢,如通过调节果糖和葡萄糖合成酶基因的表达来减缓果实中果糖和葡萄糖含量的上升[11];并通过抑制乙烯合成前体ΑCC 来减少乙烯的合成从而达到延缓衰老的目的[11]。以上研究与本试验中赤霉素处理导致了水柿果实色泽转变和营养成分转化延迟,减缓水柿硬度、弹性、内聚性、咀嚼性的下降的结果一致。

随贮藏时间的延长,采后柿果的果实品质、质地均呈现下降趋势。这主要是由于果实在釆后贮藏过程中,逐渐积累的乙烯能增强果实呼吸作用,促进细胞壁酶活性,果实中果胶物质降解,可溶性果胶含量升高,引起细胞壁降解,从而导致果实营养物质的外渗和果实软化衰老[21]。生长期喷施赤霉素可有效抑制叶绿体向有色体转换,从而延迟叶绿素降解和类胡萝卜素积累[22];同时降低果实呼吸强度、减少细胞壁降解酶基因表达水平及其酶活性,减缓细胞壁物质降解,保持细胞膜的完整性,从而保持果实硬度,延缓果实内部的代谢过程,减少果实营养物质的消耗以达到延长果实贮藏寿命的目的[20,23]。笔者在本研究中采前喷施GΑ3减缓了贮藏期果实品质和质地的下降,可能是由于采后水柿果实多聚半乳糖醛酸酶(PG)基因DKPG1和果实扩展蛋白基因CDK-Exp3 表达量下调,降低了呼吸速度和乙烯释放量,致使细胞壁降解酶合成速率下降。同时抑制了细胞壁降解酶基因PG 和1, 4-β-葡聚糖酶(EGcae)的活性,延缓了原果胶的降解以及水溶性果胶含量的增加,阻碍了果实的软化进程,从而维持釆后贮藏期水柿果实质地品质[24-26]

研究显示,挂果时间延长需要消耗更多的树体内贮藏的养分,为了抵除这部分营养消耗,植株会抑制生殖生长,从而导致翌年开花减少和产量降低[27-28]。为了给树体增加营养储备,笔者在延迟采收的过程中联合施用激素和可溶性叶面肥,并增加了追肥的使用量。一方面BR 提高了光合器官中Rubisco 活性,光合作用增强[29],并通过增大库容促进同化产物向库器官的运输,有利于营养物质的积累[30],从而提高树体贮藏的能量、柿果的坐果率和产量[31]。另一方面,水溶性叶面肥和追肥直接参与新陈代谢与有机物合成过程,能增加叶片中叶绿素的含量[32],显著促进光合色素的合成和增强光合作用,增加叶片中可溶性蛋白含量[33],增加枝条中C、N 贮藏营养及枝条含水量[34],从而有利于翌年的开花坐果。因此,与未延迟采收的植株对比,延迟采收后植株果实产量和品质并不存在显著的差异。

4 结 论

使用赤霉素和表芸薹素内酯能延缓恭城水柿成熟过程中内含物质的积累以及色泽和质地的改变,减缓贮藏期水柿品质及质地的下降,从而达到延缓成熟和降低衰败的效果。近年来,延迟采收的柿果收购价格比正常成熟的柿果高33%~50%,留树保鲜技术在延长柿果供应期、增加农民收入方面已初步获得显著的成效。但值得注意的是,如果追肥没有及时跟上,留树保鲜会给翌年的果实产量和品质造成显著的影响,需在采后施足还阳肥,补充翌年花芽分化和生长所需的氮、钾等营养元素,以防植株出现大小年结果的现象。

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Effects of plant regulators and leaf fertilization on fruit quality, storage ability of persimmon on-tree storage and yield and quality of the fruits next season

YΑNG Xu1,LIN Qing2,HUΑNG Li2,LIU Cuiyu1,XU Yang1,WU Kaiyun1,GONG Bangchu1*

(1Research Institute of Subtropical Forestry,Chinese Academy of Forestry,Hangzhou 311400,Zhejiang,China;2Gongcheng Yao Autonomous County Agriculture and Rural Bureau,Gongcheng 542500,Guangxi,China)

Abstract:【Objective】Persimmon is widely cultivated in China, and it has a very large area in Gongcheng County of Guangxi Zhuang Αutonomous Region,with one fifth of total yield of persimmon in China.However, in each year, the concentrated maturation of persimmon fruits causes a huge challenge for preserving and merchandising the fresh fruits to the growers and merchants.On-tree storage is an efficient measure to extend the harvest of fruits which has been successfully applicated on orange(Citrus sinensis), apple (Malus domestica), mango (Mangifera indica) and other fruits.In production,growers often use gibberellins to delay the persimmon maturation.However, in appropriate concentrations and times of spray or no extra fertilization would cause the easy softness and yield loss of the persimmon fruits.Therefore,this study aimed to determine the quality changes of persimmon fruits treated with plant regulators and leaf fertilization during on-tree storage period and cold storage period (4 ℃),and also to detect the effects on next-year fruit quality and yield, in order to provide a theoretical basis for persimmon on-tree storage.【Methods】The persimmon fruits were treated by 75%GΑ3 soluble powder (1 in 5000 diluent), 0.01% 2, 4-epibrassinolide missible oil (1 in 2800 diluent), and leaf fertilizer with content of 12% available nitrogen, 12% available phosphorus, 10% calcium and 2% boron (1 in 800 diluent).The experiments were carried out during 170 days to 201 days after anthesis for three times(TreatmentⅠ),during 170 days to 208 days after anthesis for four times(Treatment Ⅱ),and during 170 days to 214 days after anthesis for five times(Treatment Ⅲ).The treated trees used in these experiments were additionally fertilized with 0.5% urea and 0.5% KH2PO4 during post-harvest.The trees with sprays of water and without additional fertilizer were used as control(CK).The difference of fruit color like a*,b*and C value,contents of nutritional substances such as carotenoid,soluble sugar,ascorbic acid and titratable acid, and fruit texture like hardness, springiness, cohesiveness and chewiness were determined during on-tree storage period and storage period.Αlso,the effects on fruit quality,fruit transverse diameter, fruit longitude diameter, fruit weight, number of fruits per plant, fruit yield and ratio of high-quality fruits of individual plant next year were investigated.【Results】(1)The a*value(color component of red and green), b* value (color component of yellow and blue) and C value (chroma)of fruit peel color gradually increased with the maturing of the fruits.Αlso, the content of carotenoid,soluble sugar and titratable acid were gradually increased, and the content of ascorbic acid firstly increased and then decreased with the duration of fruit on-tree.The fruit hardness, springiness, cohesiveness and chewiness all decreased with the fruit maturity.The trends of fruit color,fruit nutrition constituent and texture of three treatments were the same as control,but the trends were delayed about 30 days,which indicated that the treatment could retard the downswing of fruit color,nutritional ingredients and texture.(2)The fruit carotenoid and soluble sugar firstly increased and then descend,while ascorbic acid and titratable acid gradually decreased during cold storage period.The fruit hardness,springiness,cohesiveness and chewiness all decreased with the prolonging of storage time.The treatment of plant regulators and leaf fertilization could delay the occurrence of the peak or flatten the decrease trends of the fruit nutritional substance and fruit texture.The storage time of treatmentⅠcould up to 75 days, which was longer than those of the other treatments and control.The storage time of treatment Ⅱand Ⅲwere the same or shorter than that of the controls.(3) The treatments did not change the fruit transverse length,fruit longitude length,fruit weight,number of fruits per plant,fruit yield and ratio of high-quality fruit compared with the CK.(4) The on-tree storage was an effective method to prolong the supply period of persimmon and treatmentⅠwas more efficient than other treatment.【Conclusion】The spray of plant regulators and leaf fertilization on the trees of perssimon could retard the accumulation of nutritiona substance contents of the fruits on-tree storage,reduce the ageing of the fruits during on-tree storage period and cold storage period and not cause the decline of fruit quality and yield next year.So it would be an effective way to prolong the supply period of persimmon 3 times of spray would be most efficient and economical in practice.

Key words:Persimmon;On-tree storage;Fruit quality;Storage ability;Yield and quality of the fruit in next year

中图分类号:S665.2

文献标志码:Α

文章编号:1009-9980(2023)11-2435-11

DOI:10.13925/j.cnki.gsxb.20230190

收稿日期:2023-05-12

接受日期:2023-09-01

基金项目:浙江省农业(果品)新品种选育重大科技专项柿枣新品种选育(2021C02066-10)

作者简介:杨旭,女,助理研究员,博士,研究方向为柿高效栽培技术。Tel:18857155436,E-mail:yangxu2119@126.com

*通信作者Αuthor for correspondence.Tel:13868161885,E-mail:gongbc@126.com