Effects of temperature on fruit thinning with ethephon in ‘Golden Delicious’ apples

The effect of temperature on the ability of 2-chloroethylphosphonic acid (ethephon), when applied at 20 mm stage of fruit development, to induce ethylene evolution of fruit and leaves and abscission of fruit and leaves was determined using 9-year-old root-bagged ‘Golden Delicious’/M.27 apple (Malus domestica Borkh.) trees in environment-controlled growth rooms. Ethephon at 400 μL L⁻¹ effectively thinned apples, and its thinning effect was not affected by increasing day/night temperature from 21.1/10 to 32.2/21.1 °C. Fruit ethylene evolution was enhanced by application of ethephon. Peak fruit ethylene evolution occurred 1 day after application of ethephon when day/night temperature was 32.2/21.1 °C whereas it occurred 2 days after application of ethephon at a day/night temperature of 21.1/10 or 26.7/15.6 °C. Ethephon increased leaf ethylene evolution drastically but it did not induce leaf abscission regardless of temperature.     

兔眼越橘茎段快繁高效技术研究

为获取兔眼越橘微体快繁高效技术体系,以越橘幼嫩茎段为试材,通过改变初代培养基、增殖培养基、生根培养基和炼苗基质的组分对24种介质进行了筛选。结果表明,初代培养基WPM+10mg/LZT能显著提高外植体的萌芽率和>1cm的枝条数;增殖培养基WPM+5mg/LZT能使新梢增殖率提高12倍;散射光处理下,生根培养基1/2WPM+0.1mg/LIBA能使试管苗生根率达到97%;草炭∶石英砂=2～3∶1的炼苗基质可以使幼苗的成活率达到99%。     

Expression of carotenogenic genes during the development and ripening of watermelon fruit

Five watermelon varieties with different flesh colors: “ZAOHUA” (red); “96B41” (pink); “307CHAOFENG” (yellow); “UNKNOWN” (orange); and “SANBAI” (white) were used to investigate the relationship between carotenoid profiles and expression of carotenoid-related genes during fruit development and ripening. In mature fruit, “ZAOHUA” and “96B41” accumulated high level of lycopene, “SANBAI” contained trace amounts of carotenoids. Through HPLC and dot blot hybridization, carotenoid content was analyzed and compared to the expression of carotenoid-related genes including Psy, Pds, Zds, CrtIso, Lcyb, Chyb, Nced1, Nced2, Nced3 during fruit development. All genes examined were expressed in all five watermelon varieties. In red and pink color varieties, the decrease of gene expression for Lcyb and Chyb at stage C (30 d after pollination) may be consistent with the high accumulation of lycopene and β-carotene. In the yellow variety, expression of the detected genes increased markedly with the onset of maturation, but little carotenoid accumulation was detected, which may be due to high level of carotenoid cleavage dioxygenases. Expression of all detected genes decreased rapidly in the white color variety upon fruit ripening, which may be attributed to a reduction in metabolic flux in the carotenoid pathway. These results imply the complex regulation of the carotenoid biosynthetic pathway in watermelon.     

利用蛋白质组学研究水果采后成熟的分子机理

果实成熟是发生在高等植物中复杂而有序的过程,由于植物种类和环境条件的不同,果实从不成熟到发育成熟过程包括了众多阶段。近年来,植物本身的生理过程与农业产业息息相关,继而影响经济效益,因此果实成熟过程的研究日益重要。果实成熟过程中,伴随着不同色素水平变化和糖等物质含量增加,果实色泽发生变化,大量生理代谢过程例如颜色、质地、风味和香气等受到外因(光照、温度)和内因(发育相关基因和激素)调控而发生变化。因而利用差异蛋白质组学方法系统研究果实从未成熟到成熟的不同生理过程和阶段分子水平上的动态变化具有十分重要的意义。到目前为止,一些重要果实及其不同发育和成熟过程的蛋白质组数据库日益完善和更新。     

乙烯利提早"国庆一号"温州蜜柑果实成熟的效应

以"国庆一号"温州蜜柑为试材,在5%果实开始转色时,以清水和100、200、400 mg/L的乙烯利进行叶面喷雾试验,以及用清水和500、1 000、2 000、4 000 mg/L的乙烯利进行涂果试验,观测了果实的着色指数、果皮厚度、单果重、可食率以及可溶性固形物、总酸、固酸比.试验结果表明:不同浓度的乙烯利叶面喷雾和涂果处理均能不同程度的促进果实着色、提早果实成熟,降低果实的总酸、提高可溶性固形物含量和固酸比,增进果实的品质.叶面喷雾以200 mg/L最好.涂果以2 000 mg/L效果最好.     

不同施肥措施对蓝莓植株生长及果实品质的影响

对伯克利蓝莓生长的3个关键期即发芽前、初夏、秋季时,施用3种肥料即硫酸铵、磷酸二铵、氮磷钾复合肥,每株按3个不同的施肥总量即25g、50g、100g进行搭配施肥试验,研究对蓝莓植株生长与果实品质的影响。结果表明,以施用NPK复合肥每株50g,分春夏秋3次分施时,蓝莓的株高、冠幅、新梢长度等生长状况,单果重、单株产量,果实的可溶性固形物含量、有机酸含量、Vc含量等品质指标均最佳。     

纤维素酶和多聚半乳糖醛酸酶与果实成熟

对果实成熟软化过程中组织超微结构变化以及Cx和PG对果实成熟软化的作用,Cx、PG在分子水平上的研究和尚待进一步研究的问题进行了系统综述:果实成熟软化与Cx、PG活性增强直接相关,PG在果实成熟软化过程中对果实着色也有着一定影响;编码Cx的基因已经在某些果实的cDNA文库中被鉴定;利用反义RNA技术对PG进行负调控是研究PG对果实成熟软化作用的主要手段。目前对Cx、PG在果实成熟过程中的作用研究主要集中在呼吸跃变型果实上,而在非呼吸跃变果实中的作用很可能有所不同。因此,研究Cx、PG在柑橘等非呼吸跃变果实成熟过程中的作用将是尚待研究的又一重要方向。     

赤霉素（GA3）对甜樱桃果实性状的影响

在果实生长第Ⅲ期的始期，用ＧＡ３溶液直接喷洒果实及叶片，果实单果重比对照增加１．２０３～２．６５５ｇ，果实直径比对照增加０．１４１～０．４５３ｃｍ，果汁的可溶性糖含量比对照提高０．１５％～２．２０％，Ｆ值均达到α＝０．０１水平．果实整齐度及着色程度均显著优于对照。综合果实性状，以１０×１Ｏ－６（１Ｏｐｐｍ）为最佳浓度。     

Analysis of blueberry (Vaccinium corymbosum L.) fruit water dynamics during growth using an ecophysiological model

Blueberry (Vaccinium corymbosum L.) fruits exhibit three growth stages associated with distinct biological processes. During these periods, water and carbon accumulate in the fruit, determining quality traits such as fruit size and sugar concentration. We adapted the Fishman-Génard model to blueberry and used it to analyse the effect of fruit load on fruit fresh mass and water dynamics, based on empirical observations of dry mass and sugar content performed throughout the fruit growth period. Different fruit load treatments were imposed during two seasons on ‘Brigitta’ blueberry plants growing under different culture systems. Increasing fruit load significantly reduced the fresh mass of the fruits at harvest, but did not affect sugar concentration, which was simulated and validated with a mean error of 7% for fresh mass and 15% for sugar concentration for the tested conditions. The most sensitive model parameters were those related to cell wall extensibility and sugar uptake. The simulations indicated that larger fresh mass of the fruit was mainly caused by increases in water fluxes rather than pressure differences. The model implementation provides the first estimates of a set of parameters which govern blueberry fruit water dynamics from fruit set to harvest.     

蓝莓修剪枝条与果渣堆肥还园利用探究

蓝莓产业迅猛发展,蓝莓田间管理和加工产生的有机废弃物如修剪枝条、果渣等逐年增长,不加以处理利用会造成资源浪费和环境污染等问题。目前,针对蓝莓废弃物处理的研究鲜有报道。从提高资源循环利用率的角度出发,结合堆肥化处理其他果树修剪枝条研究现状,从堆肥化技术的"预处理—降解菌筛选—复合菌构建—条件优化控制"等环节分析蓝莓废弃物堆肥的可行性及技术难点,展望蓝莓修剪与果渣堆肥产物还园利用的可行性,为蓝莓田间管理与加工产生的废弃物资源化利用提供方法参考。     

草酸对猕猴桃果锈清洗及耐贮性的影响

为了研究草酸的除锈作用及其在(0±0.5)℃冷藏条件下对猕猴桃果实硬度、呼吸强度、乙烯、可溶性固形物、淀粉、淀粉酶、SOD和PG变化的影响,用20g/L草酸溶液清洗猕猴桃果锈。结果表明,20g/L草酸溶液清洗效果在83.3%以上,且在冷藏条件下猕猴桃呼吸强度和乙烯释放量明显受到抑制,提高SOD活性,降低淀粉酶活性,推迟PG活性高峰的出现时间,而果实硬度、可溶性固性物和淀粉含量变化与对照无明显差异。     

Behavior of arazá (Eugenia stipitata Mc Vaugh) fruit quality traits during growth,development and ripening

The period between fruit set and full ripening of arazá fruit grown in the Colombian Amazonia was 55 ± 5 days. Three stages of a sigmoidal growth were identified and longitudinal and equatorial traits fitted a logistic model better than three-degree polynomial models. Fruit growth clearly exhibited three different physiological stages, identified as follows: S1, involving cellular division during the first 14 days; S2, maximum fruit growth, during which cellular expansion took place (up to day 50), and a final S3 state of 5 days to reach physiological maturity. After this time, the fruit can be harvested with a dull green coloration. Parenchyma was the principal fruit tissue, and no support tissues (sclerenchyma or collenchyma) were evident. The respiratory pattern of arazá fruit was climacteric, with maximum respiration rates of around 200 mg CO₂ kg⁻¹ h⁻¹, preceded by a peak of ethylene production (20 μL C₄H₄ kg⁻¹ h⁻¹), a change in skin color from green to yellow, a total soluble solids value of 5°Brix, an increase in the sucrose and fructose content up to 2.8 μmol g⁻¹, a pH which increased to 3 units, and a decrease in titratable acidity to 400 mmol H⁺ L¹⁻. Malic acid was the main organic acid in the edible pulp and ascorbic acid was present in a concentration of 17.8 μmol g⁻¹. Skin color (as measured by hue angle) combined with titratable acidity and fruit firmness can be recommended as harvest indices for arazá fruit.     

成熟猕猴桃果实中乙烯受体基因Ad-ETR2的克隆与序列分析

在分析GenBank登录的植物乙烯受体家族氨基酸和核苷酸保守区序列基础上,设计简并引物,通过RT-PCR扩增出1个657bp大小的cDNA片段,测序结果表明,该片段穴Ad-ETR2雪编码219个氨基酸,它与其它植物乙烯受体核苷酸同源性为79.9%～86.5%,氨基酸的同源性为85.4%～95.9%,序列分析推断该基因片段可能是与番茄Le-ETR1结构和功能类似的一类乙烯受体。     

Effect of fruit load on 9,10-ketol-octadecadienoic acid (KODA), GA and jasmonic acid concentrations in apple buds

The relationship between 9,10-ketol-octadecadienoic acid (KODA), GAs and jasmonic acid (JA) and flower bud formation influenced by fruit load in apples (Malus domestica Borkh.) was investigated. The endogenous KODA and JA concentrations in apical buds in plants subjected to flower thinning treatment (FTT), under which all flowers were removed were higher than those in plants subjected to heavy crop treatment (HCT), under which the number of leaves per fruit was adjusted to 20 from 60 to 120 days after full bloom (DAFB). In contrast, the gibberellic acid concentrations [total of gibberellin A₁ (GA₁) and gibberellin A₄ (GA₄)] in FTT plants were low compared with those in HCT plants. The result suggests that KODA and JA in contrast to GAs may have opposite effects on flower bud formation which is significantly influenced by fruit load in apples and that KODA and JA may also be associated with flower bud formation in apples.     

Effects of deficit irrigation on fruit maturity and quality of ‘Braeburn’ apple

Effects of deficit irrigation (DI) on fruit maturity at harvest, ripening characteristics, and changes in fruit quality during and after storage of ‘Braeburn’ apple (Malus domestica Borkh.) were studied in two experiments. In Experiment 1, irrigation treatments were a commercially irrigated control (CI), an early deficit irrigation (EDI) applied from 63 to 118 days after full bloom (DAFB), and a late deficit irrigation (LDI) applied from 118 DAFB to final harvest on 201 DAFB. Irrigation treatments in Experiment 2 were a commercially irrigated control (CI) and a whole-season deficit irrigation (WDI). These DI treatments all reduced volumetric soil water content. The LDI and WDI advanced fruit ripening but EDI did not. All DI treatments increased fruit total soluble solids (TSS) and firmness regardless of maturity but had little or no effect on titratable acidity. The differences in TSS started during fruit growth much earlier than the onset of ripening and were maintained during and following storage at 0°C. The differences in firmness also started during fruit growth and were maintained for at least 10 weeks of storage at 0°C.     

Alleviative effects of calcium acetate on defoliation and fruit drop induced by 2-chloroethylphosphonic acid in citrus

Experiments were conducted to evaluate the effects of calcium acetate on defoliation and fruit drop of ponkan (Citrus reticulata Blanco) and Meiwa kumquat (Fortunella crassifolia Swingle) trees treated with 2-chloroethylphosphonic acid (ethephon). Ethephon at 200 or 300 p.p.m. caused about 20% defoliation of ponkan trees, while this defoliation was materially alleviated by an addition of 0.05 M calcium acetate to the ethephon solution. Acceleration effects on fruit color did not differ with ethephon or ethephon + calcium acetate treatments. Ethephon at 400 p.p.m. caused about 30% fruit drop in kumquat trees, and an addition of 0.05 M calcium acetate to the solution almost completely prevented the fruit drop. Fruit color of kumquat was most advanced by the use of ethephon alone, and the addition of calcium acetate decreased the effect slightly.     

土壤地质背景对南丰蜜桔果实品质的影响

本研究在实地调查和采样分析的基础上，对南丰蜜桔原产与引种地的土壤地质背景条件进行了比较，分析了原产地与引种地之间果实品质差异的原因，还研究了南丰蜜桔树体各部位中各种元素与土壤中相应元素的关系。     

番茄乙烯受体基因反义表达对果实成熟的影响

 以乙烯受体基因LeETR1和LeETR2的转反义基因株系ale1和ale2为材料, 对果实成熟特性进行了研究。转基因番茄果实与对照相比, 呼吸速率下降, 但乙烯释放速率增加1～4倍, 呼吸高峰和乙烯跃变高峰出现的时间没有改变, 表明果实成熟起始时间没有改变。ale1果实成熟后期着色速度减慢, 红熟果色泽a值、番茄红素和类胡萝卜素含量都显著低于对照; 但果实多聚半乳糖醛酸酶活性上升和硬度下降速度都显著高于对照。这说明LeETR1基因与果实成熟品质特征的形成可能存在比较复杂的关系。     

喷施醋酸钙对蓝莓果实发育过程中关键品质的影响

探讨不同浓度醋酸钙对蓝莓果实品质的影响,为蓝莓品质调控提供理论依据。以‘粉蓝’为试材,从盛花后10 d开始,并每隔10 d在选取的蓝莓树上喷施醋酸钙,醋酸钙溶液浓度设置为0.3%、0.6%、1.0%,以喷施蒸馏水为对照,研究喷施醋酸钙对蓝莓果实关键品质的影响。结果表明,喷施醋酸钙溶液可有效提高蓝莓果实发育过程中的可溶性糖、花色苷、总酚含量及发育后期类黄酮含量,降低可滴定酸含量,提升糖酸比,其中以0.6%醋酸钙处理效果最好,说明喷施适宜浓度醋酸钙可有效提高蓝莓果实品质。相关性分析表明,花色苷与可溶性糖、糖酸比呈极显著正相关,与可滴定酸呈显著或极显著负相关,其中以0.6%醋酸钙处理各指标相关性最显著,说明能提高细胞内糖含量的因素都可以不同程度地促进花色苷的合成。     

Responses of banana fruit to pro-long coating at different times relative to the initiation of ripening

Coating banana fruit with Pro-long 24 h after initiation of ripening decreased their skin permeability to gases and depressed their O₂ content. Coating the fruit immediately before ripening initiation delayed the onset of rapid ethylene production, which normally begins as the fruit start to ripen. Coating slightly suppressed rapid C₂H₄ production when applied immediately after ripening initiation, and exerted a strong, temporary inhibition of C₂H₄ production when applied 24 h later. A climacteric rise in respiration was absent from fruit coated with Pro-long immediately before or after ripening initiation; delaying coating by a further 24 h arrested development of the climacteric in mid-rise. In mid-climacteric fruit, inhibition of C₂H₄ production by coating occurred more rapidly than inhibition of respiration. Coating the fruit delayed the chlorophyll loss which normally accompanies ripening, but the magnitude of this effect declined as the coating treatment was delayed relative to ripening initiation. The effects of coating on skin colour change and on respiration appeared to be largely independent of its effect on the fruit's C₂H₄ content.