褪黑素处理在减少桃果实冷害中的生理作用

为了揭示褪黑素处理是否可缓解桃果实的冷害伤害。本研究采用0.15 mmol/L褪黑素处理1℃下贮藏30 d的桃果实,并考察褪黑素处理对桃果实的冷害、膜脂肪酸含量和酚类代谢的影响。研究显示,与对照组相比,褪黑素处理降低了冷害发生率、冷害指数和硬度损失,并有助于维持较高比例的不饱和脂肪酸/饱和脂肪酸比例。褪黑素处理抑制桃果实中LOX的激活和MDA形成,并且抑制总酚含量损失,提高内源性水杨酸含量。这些结果表明,褪黑素处理是降低桃果实低温贮藏期间采后冷害的有效技术。     

贮前抗坏血酸处理对李果实冷害及生理生化的影响

以串红李子为试材,研究了不同浓度的抗坏血酸处理对低温下贮藏的李果实冷害及生理生化的影响。结果表明,与对照相比,贮前抗坏血酸处理能推迟李果实的后熟进程,使着色过程缓慢,呼吸强度与乙烯释放量受到一定的抑制,明显降低冷害指数,抑制李果实贮藏期间冷害的发生,尤其以低浓度（0.2%）的抗坏血酸处理抑制冷害的效果最好,可保持李果实较好的贮藏品质。     

不同热激处理对采后普鲁登斯牛角椒冷害控制作用的研究

以普鲁登斯(Prudence)牛角椒为试材,采后用45,50,55℃热水分别浸泡处理1,4 min后,置于温度为1±1℃的冷藏库贮藏。通过比较不同热激处理对普鲁登斯牛角椒冷害指数、品质指标和外观特性的影响,筛选出最佳的热激处理条件为45℃,4 min和50℃,1 min;最佳热激处理明显降低了果实冷害程度,控制了叶绿素分解速率,维持了果肉高VC含量,抑制了MDA含量的增加,贮藏42 d时冷害指数仅为12.5%和19.5%,对减轻贮藏中普鲁登斯牛角椒冷害发生的效果最佳。     

甘薯贮藏主要病害发病规律模型研究

为研究温度和湿度对贮藏甘薯病害发生的影响,利用专家咨询法和文献查询法得到甘薯贮藏时期易发病害与环境温度、湿度的关系,再使用Matlab数据分析及算法开发软件,对这些甘薯贮藏病害发生的温湿度与发病概率等数据进行规律拟合,通过对甘薯贮藏病害发生等级的划分,建立甘薯贮藏病害评价模型。该模型可以对甘薯贮藏条件进行评价,得到甘薯贮藏的最佳温湿度条件。将甘薯贮藏产生的病害的温湿度数据进行系统归纳,并在此基础上进行数学模型的建立。甘薯贮藏病害模型将有具有支持决策的功能,有利于甘薯安全贮藏,减少经济损失。     

NO诱导耐冷性在果蔬采后贮藏中的应用及研究进展

果蔬在低温贮藏环境下极易发生冷害,一氧化氮(NO)作为一种信号分子,在延缓果实衰老、减轻果实褐变及冷害程度等方面发挥着重要的作用。综述了一氧化氮及其在采后果蔬耐冷性中的应用,包括NO对果蔬耐冷性和叶绿素的影响,探究了NO诱导采后果蔬耐冷性的作用机制,研究内容包括NO对果蔬抗氧化系统、细胞膜结构、脯氨酸代谢、酚类代谢、CBF表达和其他生命活动的影响,为采后果蔬的贮藏保鲜提供理论参考。     

间隙升温降低果蔬贮藏冷害研究进展

对低温贮藏过程中冷害发生的机理以及间隙升温处理能降低果蔬贮藏冷害的原因进行了论述,并阐述了如何进行间隙升温处理及其存在的一些需要解决的问题.     

柑橘采后生理及病害研究进展

柑橘采后仍是活的有机体,由于切断了树体的营养供给,其果实品质和生理代谢等发生了重大变化。本文综述柑橘采后生理代谢(水分、营养、呼吸作用和酶活性等)的变化、生理病害(枯水病、褐斑病、冷害等)及病害防治技术(控制温度、热处理、保鲜剂处理、气调贮藏、涂膜处理、臭氧处理等)的研究进展,并指出进一步的研究方向。     

热处理对尖椒果实贮藏特性及冷害的影响

【研究目的】研究热水处理对尖椒果实贮藏冷害的影响,为尖椒的冷藏提供理论和应用依据。【方法】用热水处理（CK;处理：45℃水中浸泡5min。）尖椒果实。研究热处理对尖椒果实贮藏特性及冷害的影响。【结果】热处理抑制了贮藏过程中尖椒的腐烂率,冷藏30d时处理果的腐烂率仅为对照果实的37.5%。     

不同贮藏温度对鲜切甘薯呼吸代谢及营养成分的影响

研究了鲜切甘薯在18、10、4℃温度条件下贮藏期间的呼吸代谢及各种营养成分的变化。结果表明,鲜切甘薯在不同贮藏温度条件下,生理代谢及营养成分变化差异明显。较低的贮藏温度可显著抑制鲜切甘薯的呼吸强度、失重率及总酚含量的增加,降低营养成分的变化幅度,有利于保持鲜切甘薯的贮藏品质。     

不同温度条件下1-MCP对圆黄梨和黄金梨及丰水梨保鲜效果的影响

在不同温度条件下,研究了不同浓度1-MCP处理对圆黄梨、黄金梨和丰水梨保鲜效果的影响。试验结果表明,3个梨品种在-1.5℃条件下贮藏易发生冷害,1.0mL/L1-MCP处理果实冷害率较高;0.5mL/L1-MCP处理能明显地降低0℃和1.5℃条件下果实的果心褐变指数和果实腐烂率,贮藏期可达120天以上;不同浓度1-MCP处理对5℃条件下果实作用效果较明显,但只能应用于短期贮藏（60天左右）。     

间歇加温缓解冷藏甜椒冷害的研究

有关果蔬贮运过程的冷害大多是从恒温贮藏角度加以研究.木文根据东北地区的气候特点,从节省能源、延缓冷害的角度研究了冷藏甜椒对间歇加温的生理反应,并根据贮藏过程中的外观变化分析说明了间歇加温措施的贮藏效果及影响因素.     

热空气处理对‘白玉’枇杷品质及冷害的影响

为研究热空气处理对“白玉”枇杷贮藏品质及冷害的影响,本文以“白玉”枇杷为试材,探索了46℃热空气处理对蛋白组分含量变化的影响,并对各处理（6±1）℃冷藏期间果实冷害指数、可溶性固形物、可滴定酸、失重率、腐烂率和果实硬度进行测定。试验结果表明：冷藏及货架期间,46℃热空气处理果实可维持较高的可溶性蛋白和热稳定蛋白含量;抑制了冷藏期间果实可溶性固形物、可滴定酸含量的下降,保持了较高的果实硬度,显著降低了果实的腐烂率、失重率和冷害指数,其中以46℃热空气处理30min后冷藏效果最好。以上结果显示,果实蛋白组分含量的变化与果实采后冷藏过程中抗冷性有关,且热空气处理提高了果实的贮藏品质。     

Effect of salicylic acid treatment on alleviating postharvest chilling injury of ‘Qingnai’ plum fruit

The effects of salicylic acid (SA) treatment on chilling injury, disease incidence, electrolyte leakage, malondialdehyde (MDA) content, respiration rate and ethylene production, polyphenol oxidase (PPO) and peroxidase (POD) activities, and polyamine (PA) content of ‘Qingnai’ plum fruit were examined. Chilling injury, disease incidence, electrolyte leakage, MDA content, respiration and ethylene production of control fruit increased after about 15-30 days cold storage. Chilling injury promoted PPO and POD activities which were associated with fruit flesh browning. Accompanied by a polyamine content increase, chilling injury was positively correlated with putrescine and spermine contents in control fruit. Suppression of chilling injury by SA was associated with reducing leakage, MDA content, delayed activities of PPO and POD, and enhanced PA accumulation. SA treatment delayed the onset of the climacteric peak of respiration, and also inhibited respiration and ethylene production. The results suggest that SA treatment may be used commercially to control chilling injury in ‘Qingnai’ plum fruit during cold storage.     

Polyamines induced by hot water treatments reduce chilling injury and decay in pepper fruit

Treatment of peppers with hot water (53°C) for 4 min was found to be effective in alleviating chilling injury and reducing decay after 14 and 28 days of storage at 8°C. Treatment at 45°C for 15 min was less effective in maintaining pepper quality during storage. Packaging with low density polyethylene film significantly reduced weight loss and chilling injury during low temperature storage. Lower O₂ and higher CO₂ levels were found in internal and in-package atmospheres of heated fruit than controls. Ethylene was not detected in the in-package atmosphere of treated fruit, but was present in the control. Polyamine levels increased immediately after hot water treatments. Putrescine levels increased during storage at 8°C particularly in heat-treated fruit and in packaged fruit. A significant increase in putrescine was noted in packaged fruit treated at 53°C for 4 min after 14 days of storage. Spermine levels decreased in control fruit during storage. However, heat treatment in combination with film packaging maintained higher levels of spermine in peppers during storage than controls. These results indicated that hot water treatment in conjunction with film packaging may delay chilling injury and decay of bell peppers through a mechanism that involved elevation of polyamine levels.     

竹醋对红色甜椒贮藏中活性氧代谢的影响

为研究竹醋对红色甜椒在贮藏过程中的活性氧代谢的影响,以‘红苏珊’红色甜椒为实验材料,用蒸馏水将精制竹醋液稀释成500、1000和1500倍液,浸泡甜椒果柄3 min,以蒸馏水处理为对照(CK),擦干后装PE保鲜袋,于20℃储存。研究结果表明,500~1500倍竹醋液处理明显提高了红色甜椒的超氧化物歧化酶(SOD)和过氧化物酶(POD)活性及总抗氧化能力(T-AOC),降低了超氧阴离子(O2-·)的产生速率和过氧化氢(H2O2)含量,降低了丙二醛(MDA)含量的积累和细胞膜渗透率。其中以1500倍竹醋稀释液处理的保鲜效果最好,与CK相比较,POD活性峰值提高了1.24倍,SOD活性提高了4.6%~100%,T-AOC提高了0.12%~0.72%,O2·-产生速率降低了27.22%~47.75%,H2O2含量减少了9.46%~43.42%,MDA含量减少了8.42%~39.59%,细胞膜渗透率降低了11.56%~37.34%。这说明竹醋具有较强的抗氧化性,可以减缓红色甜椒的膜脂过氧化作用,保持细胞膜的完整性,从而延缓衰老,起到一定的保鲜作用。     

Low temperature induced changes in activity and protein levels of the enzymes associated to conversion of starch to sucrose in banana fruit

Storage at low temperature is the most frequently used method to extend the shelf life of banana fruit, and is fundamental for extended storage and transport over long distances. However, storage and transport conditions must be carefully controlled because of the high susceptibility of many commercial cultivars to chilling injury. The physiological behavior of bananas at low temperatures has been studied to identify possible mechanisms of resistance to chilling injury. The aim of this work was to evaluate differences in the starch-to-sucrose metabolism of a less tolerant and susceptible (Musa acuminata, AAA cv. Nanicão) and a more tolerant (M. acuminata × Musa balbusiana, AAB, cv. Prata) banana cultivar to chilling injury. Fruits of these cultivars were stored in chambers at 13 °C for 15 d, at which point they were transferred to 19 °C, where they were left until complete ripening. The low temperature induced significant changes in the metabolism of starch and sucrose in comparison to fruit ripened only at 19 °C. The sucrose accumulation was slightly higher in cv. Prata, and different patterns of starch degradation, sucrose synthesis, activity and protein levels of the α- and β-amylases, starch phosphorylase, sucrose synthase and sucrose phosphate synthase were detected between the cultivars. Our results suggest that starch-to-sucrose metabolism is likely part of the mechanism for cold acclimation in banana fruit, and the cultivar-dependent differences contribute to their ability to tolerate cold temperatures.     

Characterization of chilling injury in Heliotropium arborescens and Lantana camara cuttings

Simulated low-temperature shipment of Heliotropium arborescens and Lantana camara cuttings inflicted chilling injury, which was manifested in increased ion leakage in both species. Morning-harvested cuttings of both Lantana and Heliotropium were more sensitive to chilling temperatures than noon-harvested cuttings. However, this difference was expressed only during the summer in Lantana, but both in the winter and summer in Heliotropium cuttings. These results suggest that the chilling injury that occurs during shipment might be alleviated in both species by avoidance of early morning picking of cuttings.

Chilling injury in Lantana was associated with increases in reactive oxygen species (ROS) levels and ethylene production rate. On the other hand, in Heliotropium cuttings ROS levels were increased and the ethylene production rate was reduced after storage at all simulated shipment temperatures. Our results may indicate that different mechanisms of chilling injury exist in Lantana and Heliotropium.