UV-C结合1-MCP处理对香梨采后果实品质及生理活性的影响

以库尔勒香梨(Pyresbretschnei deri Rehd)为试材,研究UV-C结合1-MCP处理对香梨采后品质及生理变化的影响,为香梨采后保鲜及病害控制提供理论依据。香梨采后用UV-C结合1-MCP处理,贮藏于低温(-1℃,RH：90%~95%)条件下,研究其对果实品质和生理活性的影响。结果表明：UV-C结合1- MCP处理能够显著抑制果实硬度的下降,保持较高的可溶性固性物含量,抑制VC含量和色度角的降低。经UV-C结合1-MCP处理的香梨呼吸跃变延后,呼吸高峰降低,乙烯释放量下降,乙烯释放高峰推迟。此外,UV-C结合1-MCP处理降低了细胞膜渗透率的上升,抑制了丙二醛(MDA)含量的增加。由此表明：UV-C结合1-MCP处理能够延缓香梨采后果实的生理衰老,保持果实品质。     

茉莉酸甲酯处理对采后杏果实品质的影响

为研究不同浓度茉莉酸甲酯(MeJA)处理对采后杏果实品质的影响,分别采用0、10、100μmol/L茉莉酸甲酯处理杏,定期测定其硬度、腐烂指数、可溶性固形物(TSS)含量、可滴定酸(TA)含量、多酚氧化酶(PPO)活性、过氧化氢酶(CAT)活性和过氧化物酶(POD)活性。结果表明:MeJA处理可提高贮藏期间杏果实的CAT活性,抑制POD和PPO活性,同时降低果实的腐烂,在延缓果实软化速度的同时还提高了果实的风味和品质,对杏果TSS含量无太大影响。其中10μmol/L MeJA处理对采后杏果实的保鲜效果最佳。     

Spectral reflectance characteristics of citrus canker and other peel conditions of grapefruit

The presence of one fruit infected with citrus canker in a shipment may render the whole shipment unmarketable. Therefore it is important to classify fruit infected with citrus canker in the packinghouse before shipping the produce. The purpose of this research was to determine the significant wavelengths that could be used to classify canker among other peel conditions using grapefruit, a variety susceptible to canker. A spectrophotometer, with a wavelength range of 200–2500 nm, was used to measure the spectral reflectance data of peels from market quality fruit and fruits that were infected with cake melanose, wind scar, copper burn, greasy spot and canker. Statistical data analysis was performed on the spectral reflectance data to identify the wavelengths that had maximum discriminatory potential among the different peel conditions and to derive a discriminant function from the identified wavelengths. The discriminatory wavelengths were identified in the visible and the visible near infrared range. In addition, the classification based on the derived discriminant function resulted in 100% classification of canker. These results provide fundamental and practical use in the development of an automatic fruit sorter for canker classification based on spectral reflectance. Future research would involve the development of a vision-based classification system using the significant wavelengths identified in this study.     

百香果采后贮藏保鲜研究进展

百香果属于典型的呼吸跃变型水果，果实呼吸代谢旺盛，水分损失严重，贮藏不当会很快造成品质下降，因此贮藏保鲜是百香果采后面临的一个重要问题。本文从百香果采后生理代谢变化、影响果实品质的因素、常用采后保鲜技术等几个方面综述了目前百香果的贮藏研究现状，并进一步对百香果采后保鲜及产业发展进行了展望。     

1-MCP在果蔬体内的药代规律研究及产品开发进展

1-甲基环丙烯(1-MCP)是一种乙烯受体抑制剂,广泛应用于果蔬采后贮藏保鲜行业.本文从1-MCP在果蔬体内的吸收、与果实内部生物大分子互作及其机制、残留量及其法规约定等方面对1-MCP在果蔬体内的药代规律进行了分析.从产品开发和技术应用的角度概括了1-MCP常见的产品形式和发展趋势,梳理了1-MCP与预冷技术结合、与杀菌剂联用、与果蔬风味形成调控技术复合使用等多效保鲜技术的研发情况.通过概括分析可以发现,1-MCP的安全性高,残留量低,但有关其在果蔬体内的代谢规律和对果蔬品质的不利影响方面的研究较少,且大部分的研究集中于1-MCP的应用,长效稳定缓释剂型和复合保鲜技术将是今后的发展趋势.     

槟榔果实采后生理研究

用滴定法测定槟榔果实呼吸变化趋势。低温可延缓呼吸高峰的出现,有利于贮藏保鲜。使用放射性同位素45Ca示踪法,可证明槟榔果实内45Ca的分布有着明显的差异,果仁积累较多。低温有利于减缓45Ca的积累速度。     

二苯胺控制采后果蔬生理病害的机制

二苯胺是一种常用于控制苹果虎皮病的抗氧化剂,并且在控制其他果蔬的采后生理病害上也有一定效果。本文综述了二苯胺在控制青花椒冷害、苹果虎皮病、鸭梨黑心病及其他果蔬采后生理病害的作用机理和应用现状,探讨了二苯胺结合低氧、1—MCP及热处理等其他采后处理方法增强效果的可能性,提出今后二苯胺应用于控制果蔬贮藏期生理病害的研究方向。     

天峨龙滩珍珠李贮藏保鲜方法筛选

对龙滩珍珠李果实采后分别进行1-MCP、PE薄膜包装和8℃冷温不同组合的处理,对不同处理组合下龙滩珍珠李的保鲜效果、果实品质变化等进行测定,综合评判最优的保鲜处理组合。结果表明,对于龙滩珍珠李腐烂率抑制最显著的是冷温,综合所有贮藏品质以及酶活性分析,1-MCP的保鲜作用最为显著,而薄膜包装对于果实水分的保持效果最为明显。最佳的贮藏保鲜方式是1-MCP处理后进行薄膜包装再放入冷库贮藏以及冷链运输。     

果实采后响应病原菌侵染的生理生化及分子机制研究进展

果实采后易发生品质劣变,造成经济损失.而病原菌是导致果实采摘后品质劣变的主要原因之一.目前针对果实采后病害损失的研究主要集中于病原菌的致病机理,对于病原菌侵染后果实自身产生的抗性响应鲜有报道.本文综述了果实采后响应病原菌侵染的生理生化及其分子机制,包括病原菌侵染对果实细胞结构、果实防御酶系统的影响和果实代谢产物在抗病中的作用,探讨了果实抗病基因的研究概况,从生理生化和分子机制深入研究采摘后果实被病原菌侵染后的应答反应,为研发果实保鲜新技术提供参考.     

MADS-box基因在果实发育、成熟过程中的作用

MADS-box基因是一个序列特异的调节基因家族,所编码的蛋白为转录因子,主要由MADS盒、K盒、I区、C末端、N末端等5个部分组成,其中MADS盒非常保守。MADS-box转录因子是通过二聚体化的形式以其保守结构域与特定的DNA序列相结合来调控基因的表达的。大量的研究表明,MADS-box基因在植物花的发育上具有重要的作用,已克隆出了许多与花器官发育相关的A-C类的MADS-box基因,而且也发现了许多可以调控花时的MADS-box基因。目前,越来越多的研究表明,MADS-box基因在果实的发育、成熟中也有着重要的作用。已在矮牵牛和拟南芥中分离出与胚珠的发育密切相关的几个MADS-box基因FBP7、FBPII、STK、SHP及SEP基因。目前认为果实的成熟主要是由于乙烯的调控而引起的,但在番茄中发现1个MADS-box基因与果实的成熟相关,而且可能是跃变型和非跃变型果实共有的果实成熟调节者,首次发现MADS-box对果实成熟的作用会为用非激素的方法来调控果实成熟提供新途径。果实的开裂会严重影响某些裂果的产量,进行相关的分子调控有着重要的实际意义,已在拟南芥中发现2个MADS-box基因SHP和FUL与果实的开裂密切相关,SHP会控制裂开区域的分化,而FUL的过量表达会抑制裂片区域的木质化,FUL可以负调控SHP基因。     

褪黑素在果蔬采后保鲜中应用的文献计量及可视化分析

为全面了解褪黑素在果蔬采后保鲜领域的研究现状、研究热点和前沿趋势，以Web of Science（WoS）和中国知网（CNKI）数据库收录的褪黑素在果蔬采后保鲜中应用的研究论文为数据源，利用文献计量学方法和CiteSpace软件，通过图谱分析、聚类分析等方法，对上述发文国家、机构、作者、关键词等进行统计分析。结果显示，关于褪黑素在果蔬采后保鲜领域的研究始于2007年，主要研究国家为中国，2015年开始国内外发文量出现波动，2017年后逐渐上升。WoS中发文量最多的国家为中国，占比31.65%，发文量最多的机构为浙江大学，占比9.49%，其次是伊朗的伊玛目霍梅尼国际大学。高被引论文主要来自中国、伊朗、西班牙等国家。CNKI中国发文量较多的机构为山东农业大学、沈阳农业大学、西北农林科技大学等。国内外研究热点与趋势基本一致，专注于褪黑素处理对果蔬贮藏品质、代谢、抗氧化能力、货架期和冷害的影响，主要围绕桃、樱桃、猕猴桃、芒果、黄瓜、荔枝、葡萄、番茄等果蔬展开。关键词聚类图谱结合关键词突现分析表明，褪黑素处理对于维持果蔬贮藏品质、抑制冷害作用将继续保持其研究热度。此外，关于褪黑素处理的分子机制将会成为研究的前沿内容，应用于苹果、梨等大宗水果的研究有增加趋势，番茄可能作为一种模式植物用于该领域的研究。以上计量分析结果可为褪黑素作为一种新型保鲜剂的研究以及新技术的开发提供借鉴与参考。     

Effects of auxin and methyl jasmonate on cut rose petal growth through activation of acid invertase

Petal growth associated with flower opening depends on cell expansion caused by water influx. To understand the mechanism of flower opening and to develop a method for improving cut flower quality, we investigated the changes in the amount of soluble carbohydrates and invertase activities in rose (Rosa ‘Meivildo’) petals using attached and cut flowers, and the effects of α-napthylacetic acid (NAA) and methyl jasmonate (MeJA) on cut flowers. Cut rose flowers were harvested at the tight bud stage (TB), or mature bud stage (MB), which is the commercial harvest stage, and 2 days after TB. Cut flowers were immediately treated with deionized water or 1% (w/v) glucose. Fresh weight (FW) and the levels of soluble carbohydrates in petals in cut flowers were lower under postharvest conditions than those of attached flowers during flower opening. Although invertase activities in petals of attached flowers increased drastically during TB and MB, those in the petals harvested at TB did not increase under postharvest conditions. These results suggested that sucrose metabolism, including invertase activity, could be an important factor in cut rose flower opening to a greater extent after harvest. In addition, we tried to control flower opening by affecting invertase activities in petals of cut rose flowers. Cut flowers treated with NAA opened faster and those treated with MeJA opened later than in controls. Levels of soluble carbohydrates and invertase activity in petals were also changed by these treatments. In flowers treated with NAA, activities of both vacuolar and cell wall invertases increased 1 day after treatment and then decreased through to the end of the treatment, although activities in control flowers never increased after harvested. By contrast, cell wall invertase activity in MeJA treated flowers increased 1 day later than with the NAA treatment and remained at a relatively high level until 4 days after treatment compared to the controls. Our results suggest that inducing invertase activity in postharvest conditions may important for the quality of cut roses.     

Factors affecting the postharvest soluble solids and sugar content of tomato (Solanum lycopersicum L.) fruit

Although a large component of tomato fruit taste is sugars, the choice of tomato cultivar and the postharvest practices implemented by industry are designed to reduce crop loss and lengthen shelf-life and do not prioritize sweetness. However, because there is a growing recognition that taste and flavor are key components of tomato marketability, greater emphasis is now being placed on improving traits like sugar content. In this review the factors, both pre-, post and at harvest that influence sugar content in fruits sold at market are broadly outlined. Lines of investigation that may maximise the outcome of current practices and lead, long-term, to enhanced postharvest fruit sugar contents are suggested.     

1-MCP对果实采后生理变化的影响

对1-MCP作用效应的影响因素进行阐述,同时从果实风味、硬度、可滴定酸、可溶性固形物、果皮叶绿素、采后生理病害、乙烯生成和呼吸速率等几个方面描述1-MCP对果蔬采后贮藏保鲜的作用效果.     

BTH处理对火龙果采后抗病性及贮藏品质的影响

研究旨在探索采后浸泡苯并噻二唑(BTH)处理对火龙果采后果实抗桃吉尔霉(Gilbertella persicaria)能力、贮藏品质和抗病相关酶活性的影响,为火龙果采后贮藏提供理论和实践依据。以火龙果‘软枝大红’为材料,采用0、50、100、150、200 mg/L BTH浸泡采后火龙果果实,观察接种桃吉尔霉病斑面积及病情指数变化、采后腐烂时间和腐烂率变化,综合比较筛出最佳BTH浓度,随后进一步测定贮藏期间对照和最佳处理浓度的品质和相关酶活性的变化。与对照相比,100 mg/L BTH浸泡处理可以显著降低火龙果果实接种桃吉尔霉后的病情指数(P<0.05),提高总糖含量、降低可滴定酸含量,提升贮藏期间CAT、SOD、POD、CHI、GLU、PAL活力。100 mg/L BTH浸泡处理对采后火龙果果实抗桃吉尔霉效果最佳,可提高火龙果果实的抗病、抗氧化相关酶活性,提升贮藏品质和延长贮藏时间。     

基于产业化的热带水果贮藏保鲜技术特征、效果及应用前景

我国热带水果资源丰富，但其采收、贮藏、运输及销售全链路损耗严重，导致其商品价值降低，影响产业健康发展。梳理了国内5种产量较高的热带水果（香蕉、菠萝、荔枝、龙眼和芒果）的产业现状，分析其生理特性，并对现阶段热带水果的贮藏保鲜技术特点、保鲜效果、应用情况及存在的不足进行综述和评价，提出未来热带水果采后保鲜技术研究的发展方向和应用前景，以期为我国热带水果采后体系的构建和发展提供参考。     

生长素调节植物生长发育的研究进展

为了了解生长素对植物不同器官的影响及调控作用,本研究总结了近年来生长素在植物根、茎、叶、花、果实和种子生长发育方面的研究进展。其主要包括：生长素可以促进植物侧根和不定根的发生及生长;促进细胞分裂、伸展和分化进而促进植物茎的伸长;促进花芽萌发及影响花的形态建成和衰老;促进果实的发育和单性结实,影响果实增大和果实成熟;促进光合产物的积累,影响种子胚的形成等。除此之外还对生长素运输的生理特点、运输机制和信号转导机制等进行了梳理,了解了生长素在植物体内的调节作用主要表现在顶端优势、组织分化、器官形成、向性反应、形态建成等方面。同时还提出了生长素在网络信号调控和各器官量的分配方面研究的不足,以期为日后进一步研究提供参考。     

Analysis of sucrose metabolism during petal growth of cut roses

To clarify the mechanism of flower opening, we investigated sucrose metabolism in rose petals using attached and detached flowers. The petal fresh weight of sucrose-treated detached flowers was lower than for attached flowers, and hexose levels of these detached-flower petals were also lower. Invertase activities in attached flowers increased markedly during petal growth, but these activities in detached flowers decreased, even when detached flowers were treated with sucrose. These different invertase activities might be the cause of the different growth between attached flowers and sucrose-treated detached flowers. Our results suggest that inducing invertase activity in postharvest conditions might be important for the quality of some rose cultivars.     

四季蜜龙眼夏季开花坐果特性及传粉昆虫种类调查

为了解四季蜜龙眼夏季开花坐果特性和传粉昆虫种类,于夏季开花期间选定花穗记录雌雄花和果实数量,并以随机网捕方式采集传粉昆虫进行鉴定。结果表明:四季蜜龙眼夏季花期平均每穗开花天数为12.9天,雌雄花比例为1:6.57,授粉受精期的温度处于25～36℃之间,在较高的温度条件下雌花坐果率达到27.6%;雌花脱落占雌花数的11.1%,小果脱落占雌花数的61.3%。传粉昆虫有5目13科21种,以花金龟科的种类最多,占总数的33.3%;其次为蜂类和蝇类昆虫,分别占总数的30.1%和24.1%。     

减压贮藏对杨梅果实采后品质的影响

为探讨杨梅果实在减压条件下的贮藏效果,以“安海变”杨梅为试材,对其进行减压(0.05 MPa)处理,并于2~4℃下贮藏,定期观察杨梅果实采后品质的变化,同时对果实呼吸强度、可溶性固形物(TSS)、总糖、可滴定酸、pH、失重率、好果率进行分析对比。结果表明:减压处理能有效抑制杨梅果实冷藏期间的呼吸强度,延缓其TSS、总糖、可滴定酸含量的下降和失重率的上升,提高采后杨梅贮藏效果,使其在贮藏第16天时好果率仍保持在90%以上。这说明减压贮藏能较好地保持杨梅果实采后品质,延长其贮藏期、供应期。