采前GABA处理对芒果采后病害防治效果及果实品质的影响北大核心

探讨采前γ-氨基丁酸(GABA)处理对芒果采后病害防治效果和果实品质的影响,为寻找芒果防腐保鲜新技术提供理论依据。以贵妃芒果为试材,采前20 d对芒果喷施0.4、2.0、10.0 mmol/L GABA水溶液和清水,喷施2次,每次间隔7 d,测定采后芒果在常温(22~25℃)贮藏期间病情指数、病斑直径、果实硬度、可溶性固形物含量、维生素C含量及有机酸含量的变化。结果表明,与CK相比,采前GABA处理可显著抑制接种炭疽病菌芒果果实的病斑扩展,并显著降低采后芒果果实自然发病的病情指数,提高其防治效果,其中采前2.0 mmol/L GABA处理效果最好,贮藏12 d时防治效果为43.66%。同时,采前2.0 mmol/L GABA处理能显著延缓芒果果实硬度和维生素C含量的降低,抑制贮藏前期可溶性固形物含量的升高,保持贮藏后期较高的可溶性固形物含量。另外,采前2.0 mmol/L GABA处理可显著延缓芒果柠檬酸和莽草酸的降解,提高芒果贮藏前期的苹果酸含量和贮藏后期的奎宁酸含量。以上结果表明,采前GABA处理能有效提高采后芒果果实的抗病性,并能较好地保持果实的贮藏品质。     

1-MCP对“脱骨”李常温贮藏期品质的影响

以"脱骨"李为试材,采用常温贮藏方法,研究不同浓度1-MCP对"脱骨"李贮藏期品质和采后生理的影响。结果表明:不同浓度1-MCP均可降低果实的呼吸速率及其峰值,抑制乙烯释放,有效延缓硬度、可滴定酸含量、维生素C含量的下降速率,减少果实腐烂率,延长货架期,但对可溶性固形物含量影响不显著。此外,不同浓度1-MCP处理的效果也存在差异。在0~2.0μL/L浓度范围内,以1.5μL/L与2.0μL/L处理抑制呼吸速率和乙烯释放效果最明显,但2.0μL/L的烂果率较高。综合比较认为,1.5μL/L的1-MCP处理果实效果最好。     

不同浓度水杨酸处理对采后鸭梨果实贮藏过程中褐变的影响

以不套袋鸭梨为研究对象,采用不同浓度水杨酸处理,以水浸果实为对照,对鸭梨采后褐变指数、多酚氧化酶、酚类物质以及保护酶的活性进行测定。以有效地抑制采后鸭梨果实的黑心病,调控鸭梨果实成熟衰老的进程、改善果实品质和贮藏性能提供理论依据。结果表明:0.002、0.020、0.200mmol水杨酸处理鸭梨果实后有效减轻了腐烂和褐变的发生,其中0.200mmol水杨酸处理能显著抑制鸭梨果心中PPO活性和酚类物质的合成,并且对鸭梨果心中SOD、POD保护酶的活性促进效果最显著;而0.002mmol水杨酸处理对鸭梨果心中MDA的含量有显著抑制作用。表明水杨酸处理可以延缓果实衰老,明显抑制鸭梨果心褐变的发生,有利于延长果实的贮藏期。     

不同有机酸处理对芒果胎萌穿根、果实品质及耐贮性的影响

以芒果品种Keitt为试验材料，从果实生育期120 d起，多次喷施浓度为1 mmol/L的4种有机酸（水杨酸、苹果酸、香草酸、柠檬酸），以清水为对照。于果实生育期200 d采集果实，研究不同有机酸处理对芒果胎萌穿根、果实品质及耐贮性的影响。结果表明：有机酸处理能延缓芒果胎萌进程，抑制胎萌具有时效性，降低穿根率和抑制种子主根生长均效果显著；有机酸处理通过减轻芒果胎萌穿根影响果实品质和采后果实耐贮性，提高维生素C含量，降低维生素E、可滴定酸含量，正调控维生素C含量的积累，负调控维生素E和可滴定酸含量的积累；明显延缓芒果常温贮藏前期果实成熟进程，显著降低常温贮藏期间果实发病率。综合比较认为，在芒果果实生育期喷施浓度为1 mmol/L的柠檬酸对减轻芒果胎萌穿根危害、提升果实品质及耐贮性的效果较好。     

采前、采后外施水杨酸对葡萄成熟过程中和采后贮藏品质的影响

在自然条件下,以"巨峰"葡萄为试材,在葡萄果实转色期、成熟采收后,对葡萄果实进行外源喷施处理,分别设置0.1、1.0、10mmol·L~(-1)的水杨酸3个处理,以清水为对照,研究了不同处理对葡萄成熟过程中、采后葡萄贮藏期品质的影响。结果表明:无论任何时期的水杨酸处理都可明显抑制葡萄的腐烂,减缓果实电解质渗透率的提高,维持较高的可溶性固形物含量,保持良好的品质,延迟成熟与衰老。不同浓度水杨酸处理效果存在显著差异,综合分析认为,采前水杨酸处理、采后水杨酸处理和采后贮藏期水杨酸处理时均以1.0mmol·L~(-1)水杨酸处理浓度为最适宜。     

采前褪黑素和1-MCP处理对百香果采后贮藏品质的影响

为了探究采前褪黑素和1-MCP处理对百香果采后保鲜效果的影响,以台农一号百香果为试材,研究采前喷施200μmol/L褪黑素、5.0μg/L 1-MCP、200μmol/L褪黑素+5.0μg/L 1-MCP和清水（对照）对百香果贮藏期果实生理和营养品质的影响,为百香果采后保鲜技术的研发提供理论依据。结果表明,与对照相比,采前褪黑素和1-MCP处理均可以显著抑制百香果贮藏后期果实失重率、皱缩指数、果皮MDA含量和果皮相对电导率的增加,延缓好果率、果皮含水量和果实硬度的降低,有效保持果实可溶性固形物、可滴定酸、维生素C、可溶性蛋白含量,提高果实SOD和CAT等抗氧化酶活性。综上,采前褪黑素和1-MCP处理均可以明显延缓百香果贮藏期间果实的衰老,有效保持果实的贮藏品质,其中,褪黑素和1-MCP复合处理的效果要好于单一处理,且保鲜效果最佳。     

CPPU、ZR处理对A4无核荔枝采前落果及其品质的影响

以10年生A4无核荔枝为试材,研究不同浓度的CPPU和ZR两种细胞分裂素处理对采前落果及果实品质的影响。结果表明,CPPU 10~80mg/L、ZR 0.5~4mg/L处理均对防止A4无核荔枝采前落果和改善果实品质具有显著作用。CPPU 40mg/L处理效果最佳,可显著降低采前落果率和提高单果质量;ZR 2mg/L处理降低采前落果率效果最好,0.5mg/L处理果实横径、提高单果质量效果显著。     

次氯酸钙处理对金柑采后腐烂及抗氧化物酶活性的影响

【目的】探讨次氯酸钙在金柑果实贮藏保鲜上的应用效果。【方法】以‘金弹’(Fortunella crassifolia Swingle)为材料,分别使用质量浓度为0.15、0.6 g·L~(-1)的次氯酸钙水溶液浸泡金柑果实2 min(温度10~12℃),然后在室温为(10±2)℃、湿度为85%~90%的条件下贮藏30 d,每隔5~7 d取样1次,研究次氯酸钙处理对金柑果实腐烂率、品质以及抗氧化酶活性的影响。【结果】经0.6 g·L~(-1)次氯酸钙处理的果实总酸含量较低,在0.3%左右;贮藏第30天失重率达到4.2%,与对照相比提高1.4%;各处理间可溶性固形物含量在17%上下波动且差异不显著;次氯酸钙处理可有效降低果实腐烂率,减小果实青霉病病斑直径,提高贮藏过程中金柑果实过氧化物酶活性,减缓超氧化物歧化酶活性的降低速率,降低过氧化氢酶活性,减少过氧化氢含量,从而延缓果实衰老。【结论】次氯酸钙可有效延缓金柑果实衰老,在金柑贮藏保鲜中,不同采收期的金柑所需的次氯酸钙浓度不同,对于采收较晚的金柑,0.6 g·L~(-1)次氯酸钙浸泡2 min可有效降低果实腐烂率。     

1-MCP对美国杏李采后生理及贮藏品质的影响

以美国杏李(PluottoUSA)风味玫瑰果实为试材,研究了1-甲基环丙烯(1-methlcyclopropene)对果实采后生理和贮藏品质的影响。在室温(20±1)℃下采用浓度为0、0.5、1.0、1.5μL/L的1-MCP对风味玫瑰果实进行处理12h,处理后的果实在室温条件下贮藏。结果表明:整个贮藏过程中1.0μL/L处理组均能抑制果实的乙烯释放速率和呼吸强度,呼吸高峰延缓出现,峰值明显低于对照组;减缓果实硬度的降低和果实软化速度,在贮藏前期、中期处理组的果实硬度始终较高,末期与对照组趋于一致。降低了美国杏李果实的腐烂率的发生;有效抑制了果实可溶性固形物、可滴定酸、Vc含量的丧失,保持其贮藏品质。但在室温下1-MCP处理延长美国杏李的货架期是有限的。     

CPPU处理对采后猕猴桃品质及耐冷性的影响

以"徐香"猕猴桃为试材,于盛花后15d分别用10、20mg/L CPPU浸蘸猕猴桃幼果,清水作为对照,研究了不同浓度CPPU处理对采后"徐香"猕猴桃果实品质和耐冷性影响。结果表明:果实单果重随着CPPU使用浓度增大而增大,但相比对照,CPPU处理不同程度地降低了果实干物质含量、硬度、可溶性固形物含量、糖酸比、维生素C等品质指标,20mg/L处理对果实品质的损害大于10mg/L处理。贮藏过程中20mg/L处理的膜损伤程度最高,果实冷敏性提高,冷害发生提早,冷害率、冷害指数显著高于其它处理,贮藏结束时果实失重率高,好果率低。研究表明,高浓度的CPPU增大"徐香"猕猴桃果实的同时,显著降低了采后果实的品质及耐冷性。     

水杨酸对鸭梨果实PG、PME和呼吸速率的影响

在鸭梨果实生长发育前期,呈现一个水杨酸(SA)含量高峰,高峰过后,果实进入快速生长期。随着果实的成熟,SA含量下降。用SA喷施研究表明,不同处理时期、不同处理浓度对果实多聚半乳糖醛酸酶(PG)和果胶甲脂酶(PME)活性影响不同,其中于果实成熟前一个月(8月中下旬)喷施0.02mmol/LSA作用最强,7月上中旬各浓度处理对其作用不明显;圆片培养研究进一步表明0.02mmol/LSA可明显抑制PG和PME活性。喷施0.002～0.2mmol/LSA均明显抑制果实呼吸速率。     

草酸处理对杧果采后果实AsA-GSH循环系统的影响

 杧果（Mangifera indica L.）栽培品种‘圣心’采前套袋果实采后经5 mmol · L^-1草酸溶液浸泡10 min后常温（25 ℃）下贮藏,期间果实硬度系数、病情指数、腐烂率、黄化都显著低于对照;其中,处理果实果皮的还原型抗坏血酸（AsA）和还原型谷胱甘肽（GSH）含量保持较高,抗坏血酸氧化酶（APX）和谷胱甘肽还原酶（GR）活性在贮藏9 d后提高,同时,超氧阴离子（）生成速率、过氧化氢（H₂O₂）含量和丙二醛（MDA）含量降低,说明草酸处理可通过提高果皮AsA-GSH循环系统中抗氧化酶活性和抗氧化剂水平来增强清除活性氧自由基（ROS）能力,减轻膜脂过氧化伤害,进而有利于延缓套袋杧果采后成熟衰老进程,提高果实的商品率。     

Postharvest Attributes of “Washington Navel” Orange as Affected by Preharvest Foliar Application of Calcium Chloride,Potassium Chloride,and Salicylic Acid

ABSTRACT

To evaluate the effects of preharvest foliar application of calcium chloride (CaCl₂), potassium chloride (KCl), and salicylic acid (SA) on postharvest quantitative and qualitative attributes and storage life of “Washington navel” orange, an experiment was conducted during two consecutive years. Solutions including CaCl₂ (1.5% and 3%), KCl (1.5% and 3%), SA (0.015%, 0.03% and 0.045%), and the combination of CaCl₂, KCl, and SA were sprayed on the canopy at the end of the first stage of fruit growth one month after full bloom (fruit diameter was 20 mm) and repeated in late September. The fruits were harvested at commercial maturity stage and were stored at 5°C with 85 ± 5% relative humidity (RH) for 90 days. Quantitative and qualitative characteristics were assessed every month. Preharvest KCl treatment had no significant effect on measured parameters. However, CaCl₂ and SA treatments had the most impact on the quantitative and qualitative characteristics, such as firmness and phenolic content of fruit during storage. The SA treatment enhanced fruit appearance and nutritional value compared to the control but could not prevent the weight loss during storage. The results showed that preharvest spray of CaCl₂, KCl, SA, and their combination had positive effects on storability of “Washington navel” orange fruit during storage. However, the effect of Ca and SA was more. Application of Ca, K, and SA could be beneficial for orange postharvest instead of mixed elements fertilizers.     

Effects of post-harvest calcium chloride or salicylic acid treatments on the shelf-life and quality of apricot fruit

Summary

The purpose of this work was to estimate the effects of post-harvest calcium chloride or salicylic acid treatments on the physicochemical characteristics and shelf-life of apricot (Prunus armeniaca L.) ‘Asgar-Abad’ fruit stored at 1ºC in a normal atmosphere for 21 d after harvest. Fruit were dipped in deionised water (control), or in 40, 60, or 80 mM CaCl₂, or in 1.0, 2.0, or 3.0 mM salicylic acid (SA) for 10 min.Total soluble solids (TSS) contents, titratable acidity (TA), ascorbic acid contents, total phenolics contents, and total anti-oxidant activity were determined 7, 14, or 21 d after each treatment. Fresh weight (FW) loss, titratable acidity, and TSS contents were improved by all treatments. Fruit treated with 3 mM SA exhibited the highest phenolics content during the storage period. At the end of the storage period, the highest values of TSS were observed in the 2.0 mM and 3.0 mM SA treatments. This experiment revealed that post-harvest treatment with SA or CaCl₂ prolonged the storage-life and preserved the valuable marketing characteristics of apricot fruit, presumably because of their inhibitory effects on fruit softening, ripening, and senescence. Over 21 d in cold storage, 2.0 mM SA was found to be the best treatment to maintain fruit quality in terms of FW loss, while 60 mM CaCl₂ was optimal for achieving high ascorbic acid concentrations and enhancing the anti-oxidant capacity of fruit.     

钙处理对白凤桃果实冰温贮藏后细胞壁代谢物质的影响

以白凤桃为材料,研究了生长期和采后喷钙(1%CaCl2+0.1%Vc混合液)对冰温贮藏后果实细胞壁代谢物质的影响。结果表明,钙处理能较长时间地维持果实的硬度,生长期喷钙和采后喷钙的果肉中钙质量分数比对照分别高34.3%和3%。高钙质量分数的果实在货架期期间可减少果实中可溶性果胶和松弛结合型多糖的质量分数,这可能与细胞壁水解酶纤维素酶和果胶甲酯酶活性较低有关。说明生长期钙处理对冰温贮藏后白凤桃果实硬度的保持效果较好,在生产中使用生长期喷钙处理,可以达到延长白凤桃果实货架期的目的。     

Effects of post-harvest salicylic acid treatment on fruit quality and anti-oxidant metabolism in pineapple during cold storage

Summary

Pineapple (Ananas comosus L. ‘Comte de Paris’) fruit at commercial maturity (180 fruit per treatment, three replicates) were immersed in 0, 1.0, 3.0, or 5.0 mM salicylic acid (SA) for 15 min, then stored at 10ºC and 90% relative humidity (RH) for 20 d. After 20 d in cold storage, they were moved to 20ºC for 2 d to simulate shelf-life. Physiological and biochemical responses were studied. The results showed that the 3.0 or 5.0 mM SA treatments lowered the internal browning (IB) index, while the 5.0 mM SA treatment decreased the soluble solids content (SSC), titratable acidity (TA), and soluble sugar content, but increased ascorbic acid (AsA) levels at the end of shelf-life. Furthermore, during cold storage, all SA treatments significantly decreased the rate of tissue respiration in pineapple fruit. SA at 5.0 mM significantly decreased the activities of peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL), but increased the activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX) compared with the non-SA treated (untreated) controls. Overall, these results indicate that post-harvest treatment with 5.0 mM SA delayed the occurrence of IB in pineapple, extended its shelf-life, and maintained fruit quality during cold storage.     

Shelf-life and quality of ber (Ziziphus mauritiana Lamk) fruits after postharvest water dipping treatments and storage

Summary

An experiment was conducted to study the effect of postharvest water dipping treatments and storage conditions on shelf life and quality of ber (Ziziphus mauritianaLamk). Fresh fruits of ber ‘Umran ’ were dipped in either cold (128C) or hot (50?C) water for 5 min and packed under different storage containers i.e. corrugated fibre board boxes, sealed polythene bags and perforated polythene bags. Control fruits were packed without dipping treatment. Result showed that postharvest water dipping at 508C for 5 min significantly increased the shelf life and maintained the quality of ber fruits, particularly late in the storage period. Fruits packed in sealed polythene bags significantly lowered the loss in fruit weight, spoilage and ripening with consequent increase in acidity and organoleptic score. Interactive results showed that hot-water treated fruits stored in modified atmospheric bags (sealed polythene bags) were qualitatively better than control fruits in terms of colour, taste and appearance. The organoleptic score reveals the acceptability of these fruits even after day 8 of storage. The control fruits were not found acceptable after day 4 of storage. It is suggested that postharvest fruit dipping in hot water (508C) forfive minutes followed by packaging in sealed polythene bags can enhance the shelf life and quality of ber fruits.     

1-MCP对柿果实软化及果胶物质代谢的影响

以扁花柿为试材,研究了20℃下10μL/L的1-甲基环丙烯(1-MCP)处理对柿果实成熟软化及其果胶物质代谢的影响。结果表明:1-MCP处理不仅可推迟柿果实呼吸高峰和乙烯高峰的出现,而且还推迟了柿果实PE、PG和β-Gal酶活性的增加,从而延缓原果胶降解以及水溶性果胶含量增加,保持果肉硬度,延长贮藏期限。     

钙素对SA诱导番茄幼苗抗灰霉病的调控作用

 为探索钙对水杨酸（SA）诱导番茄（Solanum lycopersicum）幼苗抗灰霉病的作用,采用‘L402’番茄品种,通过分别喷施8 mmol • L^-1 CaCl₂和5 mmol • L^-1 EGTA后再喷施2 mmol • L^-1 SA,3 d后接种灰霉病菌孢子的方法,研究了不同处理对番茄幼苗灰霉病病情指数、活性氧积累、主要防御酶活性及其基因表达的影响。结果表明：接种灰霉病菌孢子5 d后,SA处理的番茄幼苗病情指数比对照降低37.27%,Ca + SA处理较SA处理进一步降低18%;接种1 d和2 d后,叶片中产生速率和H₂O₂含量分别出现应激高峰,且处理间存在差异,与对照相比Ca + SA处理分别提高33.05%和29.31%,EGTA + SA处理分别降低32.62%和46.34%;叶片中抗病相关酶活性和基因表达在接种病菌后也出现应激高峰,其中Ca + SA处理显著提高了PAL、几丁质酶、β–1,3–葡聚糖酶活性,EGTA处理及EGTA + SA处理显著降低了PAL、几丁质酶、β–1,3–葡聚糖酶活性。上述结果表明,Ca²⁺在SA诱导番茄抗灰霉病中具有正调控作用,而且这种作用与PAL、几丁质酶、β–1,3–葡聚糖酶活性及其基因表达密切相关。     

不同防冻剂对翠玉梨幼果冻害的效果研究

为了解决梨花期前后霜冻(俗称“倒春寒”)给果农带来的经济损失,本研究以翠玉梨幼果(盛花后12 d)为试材,利用人工气候室模拟自然界的霜降过程,研究了10种防冻剂——必博PBO、天达2116、调环酸钙、水杨酸(SA)、维生素E+丙三醇、脱落酸、6-苄氨基腺嘌呤(6-BA)、甜菜碱、脯氨酸、γ-氨基丁酸和壳聚糖对减轻梨幼果冻害的效果。结果表明,随着低温胁迫时间的延长,幼果膜脂过氧化程度逐渐增加。霜冻前采用0.5 mg/L 6-BA或3.62 mmol/L SA处理均可有效抑制丙二醛(MDA)的积累,减轻膜脂过氧化伤害,减轻幼果冻害。对筛选出来的抗冻剂进行组合和验证,发现0.5 mg/L 6-BA+3.62 mmol/L SA处理对减轻翠玉梨幼果冻害的效果最好。