采后不同贮藏条件对红阳猕猴桃生理特性的影响

以湖南省凤凰县的红阳猕猴桃为对象,研究了采后不同贮藏条件对红阳猕猴桃果实相关生理特性变化的影响,包括还原糖含量、可溶性固形物等。结果表明,红阳猕猴桃经过水杨酸或1-MCP处理后,果实的还原糖含量、VC含量以及硬度在不同贮藏期间有较大的变化,尤其是在20~30 d贮藏期内。另外,2种处理对于红阳猕猴桃色泽的影响较大,均可以有效地维持红阳猕猴桃果肉颜色及花青素的含量。     

猕猴桃果肉叶绿体的超微结构*

本文以中华猕猴桃36号为试材,研究了猕猴桃不同部位果肉叶绿体的结构特征并与叶片叶绿体做比较。结果表明,猕猴桃外果肉、中果肉和果心均存在具一定片层结构和淀粉粒的叶绿体。果肉叶绿体的基粒垛数量和基粒类囊体数目都远小于叶片叶绿体;外果肉叶片叶绿体片层似纬线平行排列,而中果肉和果心片层结构在叶绿体内弯曲扭转,排列不整齐;猕猴桃外果肉、中果肉和果心叶绿体都含有淀粉粒,但数量和体积都小于叶片叶绿体;这些观测结果为研究猕猴桃果实的光合特性提供了依据。     

毛花猕猴桃资源及其生态学特性

猕猴桃是当今世界上的一种新兴栽培果树。我国是猕猴桃的起源中心,种类繁多,资源丰富。毛花猕猴桃在猕猴桃属植物中果实仅小于中华猕猴桃,但营养丰富,尤其维生素C含量较其它种类为高。果肉翠绿色,适于鲜食和加工罐头,具有较大经济价值。1980年开始曾对广西毛花猕猴桃主要产区的     

中华猕猴桃‘金阳’果实生长发育动态分析

研究南京地区‘金阳’猕猴桃果实发育规律,为其在南京及其周边地区的推广及优质丰产提供理论依据。以5年生‘金阳’猕猴桃为试验材料,定期观察并记录‘金阳’猕猴桃从坐果到成熟软化过程中的鲜重、干重、纵横径、种子发育和果肉颜色等形态指标,并测定可溶性固形物、可溶性糖、可滴定酸、有机酸、维生素C、叶绿素和类胡萝卜素等含量。结果表明,‘金阳’猕猴桃花后0～40 d果实迅速膨大,鲜重快速增加;花后20～116 d干物质不断积累;花后83 d种子开始变黑,花后97 d种子完全变黑成熟。‘金阳’果实成熟前,可溶性固形物变化幅度较小,可溶性糖含量呈上升趋势,维生素C和可滴定酸均呈先上升后下降的趋势,有机酸中奎宁酸、苹果酸、柠檬酸的含量较高。‘金阳’花后138～154 d,果实达到可采收状态。果实采收后,硬度迅速下降,并且类胡萝卜素/叶绿素的比值升高,果肉颜色由绿色转为黄绿色,再变为黄色。南京地区可食用状态下‘金阳’猕猴桃单果重为80.5 g,果肉金黄色,维生素C的含量为129 mg/100 g,可溶性固形物的含量为14%,可滴定酸的含量为1.4%,果实经济性状良好,因此‘金阳’猕猴桃适宜在南京地区推广。     

猕猴桃果实采后成熟生理与保鲜技术研究进展

猕猴桃是一种营养价值、药用价值和鲜食率极高的高档水果。近年来,猕猴桃产业的发展呈现出几何级数的增长,为此,总结和归纳了近几年猕猴桃果实的采后生理及其果实采后的主要保鲜技术,发现猕猴桃果实的成熟生理指标主要包含果实硬度变化、果实风味及颜色变化、乙烯代谢、成熟过程中的酶活性变化以及内含物含量变化等,果实的采后保鲜技术主要为激素保鲜、化学保鲜以及物理保鲜,这项研究将有利于猕猴桃产业的健康发展。     

不同浓度臭氧处理对采后猕猴桃货架期间质构性能的影响

为探讨不同浓度臭氧处理对猕猴桃果实质地的影响,以"贵长"猕猴桃为试材,在(0±0.3)℃冷藏条件下贮藏120 d后进行货架试验,研究果实的腐烂情况,并应用质地多面分析法(TPA)对猕猴桃果肉质地参数差异变化进行研究。结果表明:臭氧能够抑制猕猴桃果实腐烂率的上升,浓度为200 mg/L的臭氧处理对果实腐烂率的抑制效果最好,货架结束时(12 d),果实腐烂率仅为13.71%;果实的硬度、弹性、凝聚性、咀嚼性和回复性相互之间均有较好的相关性,但黏着性与其他指标相关性较差,所以用硬度、弹性、凝聚性、咀嚼性和回复性作为评价猕猴桃质构性能的主要参数;与对照比较,臭氧均可更好地保持猕猴桃果实的硬度、弹性、凝聚性、咀嚼性和回复性等质构性能,其中200 mg/L臭氧处理效果优于浓度为100 mg/L和300 mg/L的臭氧处理组。因此,采后用200 mg/L臭氧处理猕猴桃能够保持果实较好的保鲜效果,更好地维持果实的质构性能。结果还表明,猕猴桃的腐烂率(x)与果肉硬度(y)在一定范围内呈现良好的线性关系,提出了拟合回归方程(y=0.244x2-24.39x+708.8,R2=0.915)用于臭氧处理猕猴桃货架期果肉质地变化的评价依据。     

1-MCP微胶囊剂对猕猴桃保鲜效果的影响

本文通过对不同剂量1-MCP微胶囊剂在猕猴桃冷藏过程中的果肉硬度、失重率以及可溶性固形物含量的变化的研究表明：1-MCP微胶囊剂对猕猴桃的硬度下降、失重率的降低具有明显的延缓作用,对可溶性固形物含量的降低也有一定的抑制作用。     

金花猕猴桃资源及其生物学特性

我国猕猴桃种质资源极其丰富,目前猕猴桃的利用,仅限于中华猕猴桃、美味猕猴桃社软枣猕猴桃、狗枣猕猴桃、毛花猕猴桃、阔叶猕猴桃等种类,而金花猕猴桃的果实仅次于中华猕猴桃,果实风味佳,是猕猴桃种类中较好吃的一种,值得开发利用。为开发利用和人工引种栽培提供科学依据,特对其资源分布、蕴藏量、生态环境和生物学特性进行了调查研究。     

请君试植猕猴桃

中华猕猴桃(Actinididchin-ensis)又名羊桃、阳桃、藤梨,属猕猴桃科的藤本植物,原产我国长江流域,现已作优良的果树广泛栽培。花期4～5月,初开时白色,后变黄,香味浓郁。浆果,表面具绒毛。优秀品种果重达100—200克。果肉颜色鲜艳,清香,酸甜适口,8—10月份成熟。种子小如芝麻。     

Analysis on Overall Buckling Behavior of Stainless Steel Welded I-beams and Design Methods

猕猴桃是一种营养价值很高的水果,属于呼吸跃变型果实,采后极易腐烂。本文综述了猕猴桃果皮、果籽、果肉、皮渣的综合利用现状及目前猕猴桃产品加工过程中减少VC损失和防褐护色关键技术的应用与研究进展,并结合国内外猕猴桃产业的发展状况,展望了猕猴桃果实的加工利用前景。     

Quality changes in sapote mamey fruit during ripening and storage

Physical and chemical changes in sapote mamey (Pouteria sapota (Jacq.) H.E. Moore and Stearn) fruit during ripening and storage at various temperatures were evaluated. Ripening was associated with flesh softening, an increase in soluble solids content (SSC), and a change in flesh color from yellow or pale pink to a dark pink or red. No changes in fruit skin color or in flesh acidity were observed as ripening progressed. Ripe fruit had 30% or higher SSC, orange or red flesh (hue angle=52; chroma=45; L=60), acidity of 6–8 mM H⁺, and flesh firmness (compression force) ≤50 N. Flesh turned brown (L* value declined) in overripe fruit. Fruit held at 27, 25, or 20°C ripened in 3.5, 5 or 7 days after harvest, respectively. Fruit kept at 10°C showed minor changes in color and firmness and a slow rate of SSC increase. Fruit stored at 10 or 15°C and then ripened at 20°C had portions of the flesh with a much higher firmness and poorer development of red color compared to other parts of the fruit. This uneven ripening was probably a result of chilling injury. The number of fruit with injury was higher at 10°C than at 15°C, and increased with storage time. The rates of fruit weight loss relative to the initial fruit weight were 0.58, 0.98 and 1.83% d⁻¹ at 10, 20 and 27°C, respectively.     

不同贮藏温度对冷处理护色荔枝贮藏品质的影响

以糯米糍等5个品种的荔枝果实为试材,研究经3～5℃冷处理结合护色后,不同贮藏温度（-2～0℃,1～4℃）对荔枝果实贮藏品质的影响。结果表明,荔枝采后经3～5℃冷处理结合保鲜剂护色后,快速置于-2～0℃条件下贮藏,可有效降低果实水分和糖、酸、VC等营养物质的损耗,保持良好的果皮、果肉色泽及口感,贮藏100～120d,好果率可达98％以上。     

光对红肉桃果肉红色形成的影响

为探讨光照是否影响红肉桃果实果肉着色,以青岛市地方红肉桃品种“大把撸”为材料,研究了不同套袋处理对着色后红肉桃果肉糖酸及色素尤其是花青苷含量变化的影响。结果表明：套袋明显抑制了果肉红色的形成;果实摘袋见光后花青苷合成能力得到恢复;套袋也降低了红肉桃果肉可滴定酸、可溶性糖、叶绿素和类胡萝卜素含量,由此证明红肉桃果实果肉红色形成在很大程度上受光照影响。     

钙处理桃果肉钙离子的分布及其与果实品质形成的关系

为探讨钙元素对桃果实品质、耐贮藏性的影响,确定最佳的叶面喷施钙元素的浓度,研究了喷施钙后,桃果肉组织中钙元素的分布特征、叶片叶绿素的含量以及对果实可溶性固形物含量(SSC)、大小、硬度和耐贮藏性的影响。结果表明,果肉中Ca2 的含量随着喷施钙元素浓度的提高而增加,当喷施CaCl2浓度为0.5%时叶绿素的含量最大,当喷施CaCl2浓度为1%时,SSC、果实大小和果肉硬度达到最大值;当喷施CaCl2浓度为2%时,放置3天后果实硬度最大。本研究确立了最佳的喷施浓度,为深入研究果实钙离子浓度梯度在果实品质形成方面的作用提供了依据。     

Identification of QTLs controlling harvest time and fruit skin color in Japanese pear (Pyrus pyrifolia Nakai)

Using an F₁ population from a cross between Japanese pear (Pyrus pyrifolia Nakai) cultivars ‘Akiakari’ and ‘Taihaku’, we performed quantitative trait locus (QTL) analysis of seven fruit traits (harvest time, fruit skin color, flesh firmness, fruit weight, acid content, total soluble solids content, and preharvest fruit drop). The constructed simple sequence repeat-based genetic linkage map of ‘Akiakari’ consisted of 208 loci and spanned 799 cM; that of ‘Taihaku’ consisted of 275 loci and spanned 1039 cM. Out of significant QTLs, two QTLs for harvest time, one for fruit skin color, and one for flesh firmness were stably detected in two successive years. The QTLs for harvest time were located at the bottom of linkage group (LG) Tai3 (nearest marker: BGA35) and at the top of LG Tai15 (nearest markers: PPACS2 and MEST050), in good accordance with results of genome-wide association study. The PPACS2 gene, a member of the ACC synthase gene family, may control harvest time, preharvest fruit drop, and fruit storage potential. One major QTL associated with fruit skin color was identified at the top of LG 8. QTLs identified in this study would be useful for marker-assisted selection in Japanese pear breeding programs.     

Characterization of six varieties of Cucumis melo L. based on morphological and physiological characters, including shelf-life of fruit

Seventy-two accessions covering six varieties of Cucumis melo were characterized by using 35 morphological characters with emphasis on shelf-life, and the relationships between shelf-life and related characters was investigated. Principal component analysis (PCA) revealed that development period of plant and fruit, size of seed and fruit, shelf-life, stem hair, flesh juiciness, netting, abscission of peduncle, rapid yellowing of epidermis at maturity, Brix value, and color of flesh and epidermis etc. were the principal characters to discriminate melon accessions examined in the present study. According to the scatter diagram, vars. acidulusand makuwa, both of which belong to the Oriental melon, are closely related because of their short growth duration, small seed, thin pericarp and poor shelf-life, while American cantaloupe (var.reticulatus) and European cantaloupe (var. cantalupensis) are rather closely related due to their climacteric fruit with orange flesh, slipped peduncle and rapid yellowing of epidermis at maturity, which is closely related with their shelf-life. PCA also indicated that var. saccharinus was closer to var. inodorus than to the other varieties, due to their requirement of long period for development, large size of seed and fruit, and half- or non-slipped peduncle. Shelf-life of melon fruit was significantly correlated with the following characters: quality of flesh, size of seed and fruit, abscission of peduncle, development periods of plant and fruit, rapid yellowing of epidermis at maturity, Brix value and color of flesh and epidermis. Accessions with good shelf-life were mostly found in vars. saccharinus and inodorus. This revised version was published online in July 2006 with corrections to the Cover Date.     

Methods to analyze physico-chemical changes during mango ripening: A multivariate approach

Canonical discriminant analysis (CDA) was used to identify the best method to discriminate between maturity and ripening stages, assessed in terms of dry matter content, firmness, color (peel and flesh), total soluble solids content attributes, before and during ‘Keitt’ mango ripening at 20 °C. Dry matter content was determined by hot-air oven and microwave oven methods. Fruit firmness was determined non-destructively by hand squeezing, with a durometer, using acoustic resonance and low-mass elastic impact methods (AWETA), as well as destructively by the penetrometer. Peel and flesh color were expressed as L*, a*, b*, h⁰ and C* values. Total soluble solids content was analyzed from filtered juice from whole fruit tissue and from unfiltered juice squeezed out by hand. Canonical discriminant analysis indicated that the durometer and the penetrometer were better methods to assess firmness than hand firmness, acoustic resonance or impact methods. The best color attributes to follow changes during early stage of ‘Keitt’ mango ripening were a* and b* values of the flesh, whereas b* value of the peel was considered better during later stages of ripening. Results of total soluble solids content in filtered juice from whole fruit tissue were less variable compared to unfiltered juice squeezed out by hand. Dry matter content was better assessed by drying the sample in a microwave oven than in a hot-air oven. A combined CDA including the best methods to assess each ripening attribute, as well as titratable acidity, showed that the best tools to assess changes in fruit during ripening were the penetrometer, followed by flesh a* value and total soluble solids content (from filtered juice from whole fruit).     

不同采收期对蟠桃贮藏品质及生理特性的影响

（1北京市农林科学院林业果树研究所,北京 100093;2中国农业大学农学与生物技术学院,北京 100094;3中国农业出版社,北京 100026）     

Does ethylene degreening affect internal quality of citrus fruit?

Citrus fruit are non-climacteric. However, exposure to exogenous ethylene, e.g., during ethylene degreening, stimulates various ripening-related processes in the peel tissue, such as destruction of the green chlorophyll pigments and accumulation of orange/yellow carotenoids. Nonetheless, it is not yet known whether exogenous ethylene affects internal ripening processes in citrus flesh. To address this question, we examined the possible effects of ethylene on taste, aroma, perceived flavor, and nutritional quality of various citrus fruit, including ‘Navel’ oranges, ‘Star Ruby’ grapefruit and ‘Satsuma’ mandarins. Exposure to ethylene enhanced peel color break, and respiration and ethylene production rates in all citrus fruit tested. However, ethylene degreening had no effect on juice total soluble solids and acid contents, and had only minor effects on contents and composition of juice aroma volatiles. Moreover, sensory analysis tests revealed that ethylene degreening did not affect the flavor of oranges and grapefruit, but marginally impaired sensory acceptability of mandarins; the latter change could be attributed, at least partially, to storage of the fruit for 5 days at 20 °C. Nevertheless, ethylene degreening did not enhance off-flavor perception or accumulation of off-flavor volatiles, nor had any effect on levels of health promoting compounds such as vitamin C, total phenols and flavonoids, or antioxidant-activity of citrus juice. We conclude that although ethylene affects peel color break, it is probably not involved in regulation of internal ripening processes in citrus fruit and, therefore, does not impair internal fruit quality.     

不同施肥处理对龙安柚果实产量和品质的影响

测定12年生龙安柚果实产量、单果重、果实色泽、果实硬度和内在品质等,进行果实色泽与内在品质间的相关性分析,探讨施肥处理对龙安柚产量和品质的影响,以期为在龙安柚生产栽培中施肥管理提供理论依据。结果表明：（1）2017年,T1、T2和T3单株产量分别比2016年增加了60.10%、19.11%、46.17%,而T4比2016年降低了30.38%。T2单株产量2年均最高（95.40、113.63 kg/株）。说明施肥处理对单株产量有显著影响,其中T2效果显著。（2）施肥处理对果皮色泽的影响不显著,但显著影响了果肉色泽。各施肥处理的果肉颜色为橙红色,其中T2的颜色较其他深,而CK的果肉颜色为黄绿色。（3）施肥显著影响了龙安柚果实的果皮、囊瓣、果肉硬度,其中T2上、下层果实硬度均较大。（4）内在品质转化糖、总糖、糖酸比、Vc含量均是T2上层果实中最高,T3中可溶性固形物(13.07%、13.07%)、固酸比是最高的,且两者中可滴定酸含量较低,说明T2、T3有利于改善果实内在品质。（5）根据果实色泽与果实品质相关性分析发现,果实色泽各指标均与果肉糖含量关系密切,说明果肉糖含量可能影响了果实色泽。