【作者】 付娟妮；

【导师】 刘兴华；

【作者基本信息】 西北农林科技大学 ， 食品科学， 2005， 硕士

【摘要】 本论文以陕西临潼石榴主栽品种净皮甜为试验材料,于2002~2003 和2003~2004 两个贮藏年度针对石榴贮藏腐烂病害的防治技术进行了研究。试验首先通过对采前甲基托布津(以下简称甲托)、易保、普德金树上喷雾处理,以及采后甲托药浴、自制SO2 缓释剂、敌霉烟剂熏蒸处理,共6 个处理18 个水平的防腐效果和贮藏品质进行了分析比较,筛选出最优处理。为了减少化学药剂的用量,将上述最优处理分别与壳聚糖、石榴皮水浸提液、丁香和大黄水浸提液进行复配后处理果实,研究各处理的防腐效果。试验通过对果实呼吸强度、酚类物质含量、乙醇含量、腐烂指数、好果率和PPO、POD、PAL、CAT等酶活性的分析比较,探讨了各处理的作用机制,揭示了石榴采后的生理变化。同时,对引起腐烂的病原真菌进行了分离鉴定,对其侵染途径、侵染循环、发病规律进行了调查,提出了防治石榴腐烂病害的综合技术措施。　试验结果表明,采前处理以甲托2000 倍稀释液树上喷雾效果最好,采后处理以甲托1500 倍稀释液药浴1　min 效果最好,两种方式对石榴果实的腐烂指数影响差异不大。试验调查了病菌的发病规律后发现,病菌的初侵染和高峰侵染期均在花期前后至果实套袋之前。因此认为,若做采前处理,时间应放在花期前后,果实套袋之前。　甲托1500 倍稀释液药浴果实,贮藏期间可降低果实的呼吸速率;显著抑制酚类物质含量的下降;快速激活保护酶POD 活性,在贮藏15d 时,其活性是对照果实的2.5 倍,并在较高活性水平上维持较长时间;减少果实内部乙醇含量的积累;使　PPO、　PAL、CAT活性受到抑制。从而有效抑制了机体过氧化过程的进行,保护了果实组织细胞结构,维持各生理代谢的正常进行,延缓了果实的衰老,提高了果实的抗病性。　甲托+壳聚糖涂膜、甲托+石榴皮水浸提液、甲托+丁香、大黄水浸提液复配处理,果实的腐烂指数和好果率均不如甲托单独处理效果好。甲托+壳聚糖涂膜处理可明显抑制果实呼吸,使　POD 活性在高水平维持较长时间,抑制PPO、PAL 活性,但同时抑制了CAT 活性,并使机体内乙醇大量积累,贮藏末期腐烂指数增高,好果率降低。推测影响该处理贮藏效果的主要原因是涂膜厚度不合适,导致果实发生部分无氧呼吸,体内乙醇积累过多,细胞中毒,细胞结构和功能严重受损无法修复,从而加速衰老,降低了抗病力。将甲托+石榴皮水浸提液、甲托+丁香、大黄水浸提液处理与对照、甲托单独处理的各生理生化指标进行比较发现,呼吸强度、乙醇含量、酚类物质含量和PPO、PAL、CAT活性均介于对照和甲托单独处理之间,说明这两种处理对石榴腐烂病害有一定的抑制作用。　试验在贮藏结束时,测定了果皮和果汁中甲托残留量,分别为0.40798mg/kg、0.03782mg/kg,均低于国家标准,安全性评价结果为安全。　利用柯赫氏法则对石榴腐烂致病菌进行分离,用分子生物学手段鉴定该菌是葡萄座更多还原

【Abstract】 In this paper,JingPiTian pomegranate, as is the main species in LinTong county ShaanXi province, is used to research inhibiting decompose of pomegranate during the storage.In this experiment, pomegranate is treated by spraying with mildothane（for short JiaTuo）、YiBao、PuDeJin pre-harvest and is treated by dipping in JiaTuo solution、fumigation of self-confect SO₂ controlled release formulation and Dimei aerosol post-harvest,and then obtains the best method base on the compare on effect of pomegranate antisepsis and storage quality of 6 factors 18 levels samples. In order to less the application amount of chemical preparations,the antisepsis effect of chitosan coating、water extract of pomegranate rind、water extract of clove and rhubarb is researched.In this paper, active mechanism of all treatments and the physiological change of pomegranate are discussed and revealed through the analysis and compare of respiration index、phenols content、ethanol content、rot index、rate of good fruit and the activity of PPO、POD、PAL and CAT.　At the same time, pathogenic fungus which makes Pomegranate rotting is isolated and identified, the infestation cycle、disciplinarian of pathogeny and infestation route of pathogenic fungus are investigated.The author concludes integrative technical measure to control the rot disease of pomegranate. The results showed that, using 2000 times JiaTuo diluent sprays pre-harvest has the best effect in all treatments ; marinating Pomegranate in 1500 times JiaTuo diluent post-harvest has the best effect in all treatments. The rot index of the two treaments is not remarkable difference. Because the time of first infestation and high peak infestation are from florescence to before setting pag, if spraying pre-harvest, the time of treatment should be from florescence to before setting bag. There have some remarkable effects of marinating Pomegranate in 1500 times JiaTuo diluent:reducing the rate of respiration during storage; restraining remarkably the degression of phenols contents; activating rapidly the activation of protective enzyme system POD（it’s activation is 2.5 times to that of comparison after 15 days storage,forthemore the high level activation maintains longer time） ; decreasing the accumulation of ethanol of fruit; restraining the activation of PPO、CAT and PAL.Accordingly,it restrains effectively the oxidation course in pomegranate fruit, protects fruit cell organization structure,maintains all kinds of physiology metabolism normally, delays the consenescence of fruit, improves the disease resistance ability of fruit. Both the effects of rot index and good fruit rate of Pomegranate which treated by using JiaTuo alone is better than that of JiaTuo +chitosan coating、JiaTuo + water extract of pomegranate rind、JiaTuo + water extract of clove and rhubarb.JiaTuo +chitosan coating treatment can restrain remarkably the rate of respiration, and can increase the contents of ethanol, although the startup speed of POD activation is same as the that of blank control, the maintain time of activation is longer. The activation of PPO and CAT also show various degrees of inhibition, the activation level of PLA which induced by pathogen is low.The main reason is the thickness of JiaTuo +chitosan coating is not fitful,It makes fruit do anaerobic respiration,and then ethanol content increases, fruit cell structure and function are damaged by high level ethanol , cell structure and function can not be recovered,so cell decreases the disease resistance ability and increases death.Comparing with every biochemical and physiological index of fruit treated by JiaTuo + water extract of pomegranate rind,JiaTuo + water extract of clove and rhubarb, blank control and alone JiaTuo control, it shows that both respiratory index ,ethanol content, phenols content and the activation of PPO、PAL and CAT lies in cross that of blank control and alone JiaTuo control.It reveals that the two treatment （JiaTuo + water extract of pomegranate rind,JiaTuo + water extract of clove and rhubarb）have some effects to restrain pathogen , protect organization and delay consenescence on pomegranate fruit during storage. The peel and juice of pomegranate are determined at the end of storage.The results is 0.40798mg/kg and 0.03782mg/kg, shows that the residue is lower than national standard and is safe for eating. Isolation and identify the pathogen of pomegranate shows that it is Botryosphaeria dothidea.　There are two kinds rot symptom which aroused by Botryosphaeria dothidea depend on atmosphere humidity: the first is pericarp shows waterlogged brown clot at the beginning of infestation, then pericarp becomes black brown and have some particulates which is difficult to scrape down, fruitage becomes spongy rot and the seed is abnormity;the second is pericarp shows brown sunken dry area spot and rot speed is slowly than spongy rot. Botryosphaeria dothidea lives through the winter with the form of perithecium and bourgeons in warm wet springtime.It spreads through rainwater, air current and insect, and can enter and infest bud, young fruit or fruit from calyx lenticel injured scarfskin and hypanthium, fastigium of pathogeny is from May to July, Botryosphaeria dothidea lives through the winter inside of dry fruit and rotten tree bark. In this thesis, for the first time identify the pathogen of pomegranate with the gene method,and know that it is Botryosphaeria dothidea.First research systematacially the decompose mechanism of pomegranate, and reveal that JiaTuo 2000 times diluent spraying or marinating pomegranate in 1500 times can inhibiting pomegranate decay. Forthmore,the author discuss the inhibition mechanism of JiaTuo.更多还原