The effect of storage temperature on quality and decay percentage of ‘Pairi’ and ‘Taimour’ mango fruits

The effects of storage temperatures, especially chilling-temperatures, and the duration of exposure to them, on quality and decay percentage, and on the shelf-life of ‘Pairi’ and ‘Taimour’ mango fruits were studied. ‘Taimour’ fruits had better keeping-quality, storage ability and a longer marketing period than ‘Pairi’ fruits under all storage temperatures. Both cultivars were affected by storing at 0 °C and the severity of chilling was proportional to the duration of cold storage. ‘Taimour’ fruits were less sensitive to chilling-injury than ‘Pairi’ fruits. Storage at 5 °C or slightly higher was the most suitable temperature for both cultivars, followed by 10 °C.     

Growth of Vitis vinifera L. and Vitis aestivalis Michx. as Affected by Temperature

Abstract

Four European (Vitis vinifera L.) winegrape cvs., ‘Semillon’, ‘Pinot Noir,’ ‘Chardonnay’, and ‘Cabernet Sauvignon’, and one American (Vitis aestivalis Michx.) winegrape cv. ‘Cynthiana’, were subjected to three temperature regimes in growth chambers set at 20/15°C, 30/ 25°C, or 40/35°C, for 16/8 hr day/night to determine the influence of temperatures on vine growth and development. In general, the best temperature for shoot and root growth 28 days after temperature treatments was 20/15°C for ‘Semillon’, ‘Cabernet Sauvignon’, and ‘Cynthiana’, and 30/25°C for ‘Pinot Noir’ and ‘Chardonnay’. Although 40/35°C reduced number of leaves, shoots, tendrils, and internodes, total leaf area (LA), and total shoot biomass of all the cultivars, the reduction was more pronounced in ‘Cynthiana’ than in the European cultivars. The average reduction in number of leaves at 40/35°C for the European cultivars was 47%, compared with 92% for ‘Cynthiana’. The two types of grapes adapted differently to high temperature. Shoot growth in the European cultivars continued under high temperature, whereas growth ceased in ‘Cynthiana’. Roots of ‘Cynthiana’, however, were less susceptible to the adverse effect of high temperatures than were the shoots. This study shows that the European cultivars were relatively more tolerant to high temperature than the American cultivar and they have a potential for production of wine in the climate of south central Kansas.     

Effect of intermittent warming on the reduction of chilling injury of Villa Franka lemon fruits stored at cold temperature

Storing lemon fruits at temperatures below 13°C caused chilling injury, namely physiological and chemical disorders and the development of excessive rot. However, warming the fruit for 7 days at 13°C after every 21 days in cold storage prevented chilling injury and enabled lemons to be kept in storage for six months and longer and retain marketable quality.     

Storage capability at different temperatures of lemons grown in Israel

For prolonged storage of lemons, the best temperature to avoid rots and physiological disorders such as internal browning and peel pitting, was 14°C; for short periods only, storage at lower temperatures, 2–8°C, did not cause damage. Physiological disorders appeared in storage earlier, the lower the storage temperatures, and in fruit picked at a less ripe stage. The general appearance of the fruit is better when stored at the lower temperature. Color development, chemical changes, weight loss, respiration rate and ethylene evolution during storage of lemons at different temperatures and stages of maturity were examined.     

The effects of storage temperature and fruit size on firmness,extractable juice,woolliness and browning in two nectarine cultivars

Fruit firmness, extractable juice, woolliness and browning of the mesocarp tissue in ‘Independence’ and ‘Flavortop’ nectarines stored at —0.5°, 3°, 5° and 7°C for four weeks were determined during ripening at 15°C. The firmness of both ‘Independence’ and ‘Flavortop’ during ripening decreased as storage temperatures increased. The percentage extractable juice after cold storage and during ripening varied considerably between cultivars and between the storage temperatures. The extractable juice of fruit stored at higher temperatures tended to increase during ripening, whereas fruit stored at lower temperatures tended to decrease first before increasing. At storage temperatures of —0.5° and 3°C both cultivars passed through a stage of woolliness during ripening, while less woolliness occurred after storage at 5° and 7°C. In both cultivars the percentage extractable juice during ripening was higher on average at storage temperatures of 5° and 7°C. Severe browning of mesocarp tissue in both cultivars occurred during ripening after storage at 3°C. The effect of fruit size on changes in firmness, development of woolliness and mesocarp browning in ‘Flavortop’ nectarines stored at — 0.5°C for four weeks and ripened at 15°C was also determined. Larger nectarines lost firmness more rapidly, woolliness occurred sooner and the mesocarp tissue was more prone to browning than smaller fruit during ripening.     

Fermentative metabolism in ‘Conference’ pears under various storage conditions

Summary

The aim of this work was to investigate the fermentative metabolism of ‘Conference’ pears during different storage regimes. Fruits were stored at 0°C in the following controlled atmosphere (CA) conditions: 6 kPa CO₂ + 0.5 kPa O₂;3 kPa CO₂ + 1 kPa O₂; or 1 kPa CO₂ + 2 kPa O₂; and also in regular air (RA) as a control. Pears kept in RA showed low pyruvate decarboxylase (PDC) and alcohol dehydrogensase (ADH) activities, and correspondingly low levels of ethanol and acetaldehyde production as long as the fruits were maintained at low temperatures. During shelf-life at 20°C, RA-fruits released higher amounts of acetaldehyde, while ethanol production remained low. Lactate concentrations in RA-stored pears increased continuously in the second part of the storage period and during shelf-life, while lactate dehydrogenase (LDH) activity remained low. During CA-storage, ‘Conference’ pears showed continuous increases in the activities of PDC and ADH, mainly in fruits stored under high CO₂ and/or low O₂ partial pressures. The production of ethanol and acetaldehyde was not influenced in fruits stored in 6 kPa CO₂ + 0.5 kPa O₂. LDH activity in CA-stored pears increased during storage, while lactate concentrations diminished. During shelf-life at 20°C, the concentrations of all measured fermentation products increased, particularly acetaldehyde and lactate. We conclude that PDC, ADH, and LDH activities are not rate-limiting factors in the accumulation of fermentation products in ‘Conference’ pears during storage and shelf-life at 20°C.     

Asymmetric growth of citrus fruit peel induced by localized application of gibberellins in lanolin pastes

Lanolin pastes containing 0.02–1.0% gibberellin A₄₊₇(GA₄₊₇) were applied to one side of developing citrus fruitlets and caused thickening of the peel in the proximity of the treated zone. Enlargement of albedo (= the white portion of citrus peel) cells was involved, as revealed by scanning electron microscopy. The flavedo (= the coloured portion of the peel) and the pulp were not affected by the hormone. Gibberellin A₃ was slightly less active than GA₄₊₇. Cultivars with a naturally thick peel, such as ‘Marsh’ grapefruit (Citrus paradisi Macf.) and ‘Shamouti’ orange (Citrus sinensis (L.) Osbeck) responded more strongly than thin-peel cultivars. The role of gibberellins in the differential growth of citrus fruit tissues is discussed.     

Effect of temperature manipulation during storage and ripening on firmness,extractable juice and woolliness in nectarines

‘Independence’ nectarines were stored at — 0.5°C for three or four weeks or at 3°C for four weeks or kept at room temperature for 18 h prior to storage for four weeks at -0.5°C. After cold storage, fruit from all treatments was ripened at 10°, 15°or20°C. In all treatments the percentage woolly fruit initially increased to high values and thereafter decreased with further ripening. The rate of increase and decrease in woolliness depended on the ripening temperature. A storage period of four weeks at — 0.5°C resulted more woolliness during subsequent ripening. Woolliness persisted longer after a four-week cold storage period than after a three-week one. When fruit was delayed at room temperature prior to cold storage, woolliness generally developed earlier and to a lesser extent during ripening. At all ripening temperatures initial storage at 3°C resulted in most woolliness extending over the longest period. In addition, browning of the meso- carp tissue occurred only in fruit cold stored at 3°C.-The delay period before cold storage decreased fruit firmness by 15.7 to 17.6 N. Except for fruit subjected to the delay period, the extractable juice in fruit of all treatments first decreased during ripening to low values then increased.     

Effects of high-humidity storage on quality,decay and storage life of cherry,lemon and peach fruits

Sweet cherries (Prunus avium (L.) ‘Lambert’ and ‘Blackboy’), lemons (Citrus limon (L.) Burm. f. ‘Lisbon’) and peaches (Prunus persica (L.) Batsch, ‘Summerset’) were stored at 77–83, 90–94 and 95–99% RH (high humidity) at near-optimal storage temperatures after harvest and treatment with fungicides. High-humidity storage did not increase the storage life of peaches held at 0°C, but the life expectancy of cherries (both cultivars) was extended by 7–10 days at 0°C, and of lemons by at least 4 weeks at 10°C when fruit were stored at 95–99% RH compared with levels below 95%. The beneficial effects of high humidity were attributed to retardation of peel desiccation and associated reductions in fruit deformation, peel de-greening, chilling-injury and decay in lemons and to the maintenance of a fresher stalk and a firmer, less shrivelled fruit in cherries. High humidity had no effect on decay in cherries or peaches, but it significantly reduced weight loss and delayed the appearance of shrivel in peaches stored at 0°C. However, after storage at high humidity for 4 weeks, peaches ripened with low rates of C₂H₄ evolution and showed severe low-temperature injury, slight peeling-injury and a poor flavour ex-store.     

The effect of preharvest calcium sprays on quality attributes,physicochemical aspects of cell wall components and susceptibility to brown rot of peach fruits (Prunus persica L. cv. Andross)

This study was planned to evaluate the effect of preharvest calcium sprays on physicochemical aspects of cell wall components, activity patterns of pectin-modifying enzymes and susceptibility to brown rot (Monilinia fructicola) of peach fruits (Prunus persica L. cv. ‘Andross’). Six or 10 preharvest calcium sprays were applied with two different formulas (calcium chloride and an ethylenediamine tetraacetic acid (EDTA) chelated calcium form) in equimolar calcium concentration (0.12% Ca, w/v). After harvest, peach fruits were cold stored (0 °C, 95% R.H.) up to 4 weeks. Calcium content increased significantly in the calcium-sprayed peaches both in the peel (25–42%) and in the flesh (11–17%), 1 d after harvest. Calcium chloride sprays were more effective than those of chelated calcium, whereas the increase of calcium content in the fruits seems to be unaffected by the 6 or 10 calcium sprays. The increase of cell wall calcium corresponded to increase of calcium in the insoluble pectin fraction, whereas no differences were detected in the calcium of water-soluble pectin fraction. Ethylene production, respiration rate, uronic acid content and activity of pectin-modifying enzymes did not indicate substantial differentiations by preharvest calcium sprays as ripening progressed after harvest or cold storage. Calcium sprays resulted in significant decrease of brown rot development, although no effect on disease incidence was recorded.     

Polyphenoloxidase activity during ripening and chilling stress in ‘Manila’ mangoes

Summary

‘Manila’ mangoes were stored at 6 or 12°C, while a control lot was ripened at 258C. Polyphenoloxidase activity was measured in pulp and peel of mangoes during normal ripening and chilling-stress conditions. Compositional parameters (textural hardness, pH, acidity, and soluble solids) were monitored during ripening and chilling injury (CI) was assessed by visual inspection. PPO activity increased in refrigerated mangoes but fruit stored at 6°C displayed greater activity than those stored at 12°C. Both temperatures produced a peak in enzyme activity at day 16 of storage. Peel browning and acidity correlated with PPO activity (r.=.0.9073 and 0.9818) at 6°C. After the PPO peak was observed at day 16, refrigerated mangoes showed lower enzyme activities; however external browning became more pronounced.     

‘寒富’苹果枝条低温适应性研究

以‘寒富’苹果及其亲本系‘东光’、‘富士’为试材,对人工低温胁迫下枝条电导率进行了研究。结果表明:3个苹果品种枝条的电导率随温度的降低而升高,但品种之间差异不明显。结合Logistic方程计算出的‘寒富’、‘东光’、‘富士’的低温半致死温度分别为-43.3、-45.3、-37.5℃。通过对3个苹果品种枝条电导率的比较表明,‘东光’苹果低温适应性最强,‘富士’苹果对低温适应能力最弱,‘寒富’苹果居中。     

金叶莸和榆叶梅抗寒性研究

以金叶莸、榆叶梅1年生离体枝条为试验材料,经过6个不同低温的处理,用电导法测定其相对电导率,并测定低温下植物丙二醛含量、脯氨酸含量的变化。研究结果表明,低温对膜稳定性有影响,这2种植物的抗寒性具有明显差异。榆叶梅的抗性较强,而金叶莸较差。     

Pollination effects on fruit production of ‘Star Ruby’ grapefruit (Citrus paradisi Macf.)

Flowers of ‘Star Ruby’ grapefruit were hand-pollinated with ‘Valencia’ orange (C. sinensis (L.) Osbeck), ‘Marrs’ orange, ‘Ruby Red’ grapefruit (C. paradisi Macf.) and ‘Star Ruby’ grapefruit pollen. Flowers cross-pollinated with ‘Ruby Red’ pollen produced more fruit than did self-pollinated flowers. Flowers cross-pollinated with either ‘Marrs’ or ‘Valencia’ pollen did not produce as many fruit as ‘Ruby Red’-pollinated flowers, nor did they produce more fruit than self-pollinated or open-pollinated flowers. Few fruit were produced when ‘Star Ruby’ flowers were not hand-pollinated. Less than 0.5% of ‘Star Ruby’ pollen germinated in 15–25% sucrose solutions, whereas between 6 and 21% of the pollen from ‘Valencia’, ‘Marrs’ and ‘Ruby Red’ germinated. The number of fully-developed seeds per fruit was increased only when ‘Marrs’ pollen was used. These data show that ‘Star Ruby’ produces very little functional pollen and few functional ovules, and suggests that ‘Star Ruby’ has weak parthenocarpic ability.     

Changes in Ripening Behaviors of 1-MCP-Treated ‘d’Anjou' Pears After Storage

Abstract

1-Methylcyclopropene (1-MCP), an ethylene action inhibitor, was applied to ‘d’Anjou' pears (Pyrus communis L.) at 20°C between 2 and 5 days after harvest. Scald of ‘d’Anjou' pears was completely controlled by 1-MCP at a concentration between 0.05 and 0.3 µl l1 after a prolonged cold storage plus 7 days of exposure to an environment with or without 500 µl l1 ethylene at a temperature of 20°C or 25°C. 1-MCP inhibited the biosyntheses of α-farnesene and its oxidative products (conjugated trienes) and thus controlled scald. However, fruit treated with the above concentrations of 1-MCP did not ripen normally in an environment with or without ethylene. Ethylene production and fruit softening of 1-MCP-treated ‘d’Anjou' pears were inhibited during 7 and 15 days at 20°C. ‘d’Anjou' fruit treated with 0.01 and 0.02 µl l¹ 1-MCP ripened normally on day 7 at 20°C after 3 months of cold storage at ? 1°C, and ripened fruit did not develop any incidence of scald. Untreated fruit developed substantial scald. After 4 months of storage or longer, both untreated fruit and fruit treated with 0.01 and 0.02 µl l 1 1-MCP developed an unacceptable incidence of scald upon ripening. Thus, use of other scald control methods may be necessary in addition to treatment with a low dosage of 1-MCP to insure both normal ripening and scald control for d'Anjou pear fruit from the Mid-Columbia district.     

Erh?hung der Temperatur bei der Apfellagerung durch Einsatz von 1-MCP

The investigations should purify whether the temperature during apple storage can be increased by application of 1-MCP to decrease energy consumption and costs. The investigations were carried out over 2 years with the following treatments: Year 1: The apple cultivars ‘Elstar, Elshof’ and ‘Gala, Must’ were investigated. For both cultivars 3 different storage temperatures (1, 2 and 4°C) with and without application of 1-MCP were examined. Each temperature and 1-MCP treatment was investigated both under CA-/ULO-conditions with 1.5% O₂ and 2% CO₂ and in cold storage with normal atmosphere. Year 2: The apple cultivars ‘Jonagold, Jonica’ und ‘Golden Delicious, Weinsberg’ were investigated. For both cultivars 3 different storage temperatures (1, 2 and 4°C) with and without application of 1-MCP were examined. Each temperature and 1-MCP treatment was investigated both under CA-/ULO-conditions with 1.5% O₂ and 3% CO₂ and in cold storage with normal atmosphere. The influence of temperature, storage atmosphere and 1-MCP application on fruit firmness, soluble dry matter (sugar) and fruit acid was investigated on 6 dates (September to October in the first year) respectively on 5 dates (October to March) during the storage period. Following results were obtained:

1. In the first year storage temperature did not influence the content of soluble dry matter of both cultivars. Application of 1-MCP led to a less decomposition of soluble dry matter. In the second year the content of soluble dry matter decreased slightly with increasing temperatures. A clear positive effect of 1-MCP-application was not noticeable. Altogether an increase of storage temperature has no or only a small influence of the content of soluble dry matter. 1-MCP can slow down the decomposition of soluble dry matter.
2. An increase of storage temperature had no or only a small influence of fruit firmness. With increasing storage temperature fruit firmness decreased slightly.1-MCP application led to a higher fruit firmness, especially during cold storage in normal atmosphere. In both years all cultivars showed a same or higher fruit firmness at 4°C with 1-MCP application under CA-/ULO-conditions as at 1°C without 1-MCP application under CA-/ULO-conditions.
3. An increase of storage temperature had no or only a small influence of the content of fruit acid.1-MCP application under CA-/ULO-conditions reduced the decomposition of fruit acid. In both years usually all cultivars showed a same or higher content of fruit acid at 4°C with 1-MCP application under CA-/ULO-conditions as at 1°C without 1-MCP application under CA-/ULO-conditions.

The results show that an increasing of storage temperature under CA-/ULO-conditions and with 1-MCP application has no negative influence on fruit quality in comparison to fruits which were stored under CA-/ULO-conditions at low temperatures without 1-MCP application.     

1-MCP处理对“东红”猕猴桃货架期品质的影响

以"东红"猕猴桃为试材,通过采后用不同浓度(0、0.25、0.50、0.75μL·L^-1)1-甲基环丙烯(1-methylcyclopropene,1-MCP)进行处理后,将果实至于(20.0±0.5)℃层析冷柜中对其进行货架期贮藏,研究"东红"猕猴桃果实品质的变化,以期为延长猕猴桃货架期品质提供参考依据。结果表明:0.75μL·L^-11-MCP能够有效地抑制"东红"猕猴桃果实硬度、b*值、超氧化物歧化酶(SOD)活性及过氧化氢酶(CAT)活性的下降;0.75μL·L^-1及0.50μL·L^-11-MCP均能够显著降低"东红"猕猴桃果实呼吸强度、乙烯生成速率和脂氧合酶(LOX)活性;0.25、0.50、0.75μL·L^-11-MCP能够更好地推迟"东红"猕猴桃果实可溶性固形物含量的上升,而不同浓度1-MCP处理间对"东红"猕猴桃果实可滴定酸含量的作用效果无显著差异。综合比较,0.75μL·L^-11-MCP能够更好地保持"东红"猕猴桃的货架期品质,其次为0.50μL·L^-11-MCP。综合考虑"东红"猕猴桃货架期品质变化及成本,建议"东红"猕猴桃的1-MCP使用浓度为0.50~0.75μL·L^-1。     

自发气调包装对‘新梨7号’果实品质及耐贮性的影响

【目的】明确不同厚度的保鲜袋自发气调包装对‘新梨7号’采后生理和贮藏品质的影响。【方法】将‘新梨7号’分别采用厚度为0.02、0.03、0.04和0.05 mm的PE袋扎口处理形成自发气调环境,于温度(0±0.5)℃、相对湿度90%~95%条件下贮藏,并以0.02 mm PE袋不扎口为对照处理,定期测定各处理相关指标,并统计果实腐烂率、果柄保鲜指数。【结果】不同厚度保鲜袋内气体成分在第30天时达到平衡,气调能力水平由高到低依次为0.05 mm>0.04 mm>0.03 mm>0.02 mm PE袋,采用上述包装进行自发气调处理均能够抑制果皮h°值、Fm、Fv和Fv/Fm的下降;果柄保鲜指数随保鲜袋厚度增加显著升高,果实腐烂率显著低于对照;显著降低果实维生素C含量,冷藏后期货架期间各处理果实硬度、可滴定酸含量显著高于对照。各处理乙醛含量极低,乙醇检测不出。【结论】‘新梨7号’为较耐CO2且极不易发生褐变的梨果品种。筛选出适合‘新梨7号’自发气调包装袋为0.03 mm PE袋,可有效保持果面绿色,降低果实腐烂率但显著降低维生素C含量。     

不同授粉方式下‘度尾蜜柚’亲和性及其生物学效应

 通过3种授粉处理, 对‘度尾蜜柚’自交不亲和性及产生的若干生物学效应进行了观察。结果表明: 在正常自交的情况下, ‘度尾蜜柚’存在不亲和性, 大部分果实无籽, 随着果实的成熟, 果形指数逐步降低, 中心柱空心, 果顶皮层厚度逐渐变薄, 裂瓣大量产生, 同时一部分果实顶部裂开, 霉菌侵染果肉, 失去食用价值; 蕾期自交能在一定程度上克服不亲和性, 产生少量的种子, 能有效防止果实横向和纵向不均衡生长, 促进果实中心柱较好地保持实心状态, 果顶皮层增厚, 从而显著降低了裂果和裂瓣; 用‘琯溪蜜柚’花粉异交授粉, 果实种子数显著增多, 果形指数变化较小, 中心柱实心, 少有裂果和裂瓣发生, 但食用品质受到影响。     

套袋对‘三红蜜柚’果实着色的影响

【目的】‘三红蜜柚’[Citrus maxima(Brum.)Merr.‘Sanhongmiyou’]的海绵层和果肉红色,外果皮橙黄色,经套袋后也呈现紫红色,但套袋对外果皮呈色的作用机制尚不清楚。因此,本研究通过分析不同套袋对外果皮色素积累的影响,筛选出最适套袋方案,指导生产,也为今后进一步研究果面色泽形成机理提供研究基础。【方法】以’三红蜜柚’果实为试材,分别选用3种不同的果袋对果实进行套袋,以不套袋作为对照,测定果实在发育期间的外果皮色泽参数、叶绿素和类胡萝卜素含量,使用超高效液相色谱法测定外果皮番茄红素、β-胡萝卜素和玉米黄素的含量。【结果】3种套袋处理的果皮亮度值L*、红绿色度值a*、黄蓝色度值b*和色泽饱和度在果实发育过程中均呈上升趋势,显著高于对照组;在3种套袋处理间,L*值无显著差异,处理A和处理B的果实比处理C的果实更早退绿,更早着色。相比较于对照组,套袋处理能够显著提高成熟果实果皮的番茄红素含量,不同处理间的果皮番茄红素含量差异显著,其中,处理A的果皮番茄红素含量最高,达44.54 mg·kg^-1。在果实发育过程中,套袋处理果实的果皮β-胡萝卜素、玉米黄素、叶绿素a、叶绿素b和类胡萝卜素的含量均呈下降趋势,显著低于对照组。【结论】套袋显著降低‘三红蜜柚’果实的果皮叶绿素含量,促使果皮提前退绿;双层和三层果袋显著提高成熟期果实的果皮番茄红素含量,增加果皮的红色成分,有效提高‘三红蜜柚’果实的果面着色效果。