Prochloraz采后处理对苹果贮藏期病害的控制

经Prochloraz处理对苹果采后青霉病(peniciliumexpansum)的抑制效果进行了研究。结果表明,Prochloraz对P.expansum具有明显的抑制作用,浸泡处理可明显地降低损伤接种P.expansum的病斑直径,其中以500mg/LProchloraz在40℃浸泡处理对降低损伤接种P.expansum的病斑直径效果最佳;不同处理时间对病斑直径也有一定的影响,以500mg/LProchloraz处理2min的抑制效果最佳。

Sensitivity of Fusarium graminearum to Carbendazim and Prochloraz

[ Objective] The paper was to understand the resistance of Fusarium graminearum to carbendazim and prochloraz in the main wheat producing areas in Hubei Province. [ Method] Totally 350 F. graminearum strains isolated in 2014 were determined to clear their sensitivity to carbendazim and prochloraz. [ Result] ALl isolates were sensitive to carbendazim and procidoraz in Hubei Province, and carbendazim was still valuable in controlling Fusarium head blight. The control effect of prochloraz was better than that of carbendazim, and the combination of prochloraz and carbendazim at the proportion of 1：7 received the best control effect. [ Conclusion ] Combination of chemical agents will occupy a more and more important position in future prevention and control against Fusarium head blight.

Effect of Compound Treatment with Prochloraz and Chitosan on the Physicochemical Indexes of Refrigerated Citrus Gonggan

[Objectives]This study was conducted to investigate the synergized preservation effect of different concentrations of prochloraz and chitosan on citrus Gonggan,so as to prolong the sales period of Gonggan.[Methods]"Zhongshan Gonggan" was used as a material.The Gonggan fruit was soaked with prochloraz (250,300 and 350 mg/L) and then coated with different concentrations of chitosan (1.0% and 1.5%),respectively.The good fruit rate,weight loss rate and titratable acid (TA),reducing sugar,total soluble solids (TSS) and Vc contents were used as evaluation indexes to investigate the preservation effect of Gonggan during cold storage.[Results]The treatment of prochloraz plus chitosan can significantly prolong the shelf life of Gonggan as it can inhibit the decline of good fruit rate,reduce the weight loss rate,and slow down the degradation and loss of titratable acid,reducing sugar,soluble solids and Vc.The 350 mg/L prochloraz+1.0% chitosan treatment was superior to other treatments.[Conclusions]This study provides a theoretical basis for better prolonging the storage period of Gonggan.

Residue and Safety Use of 45% Prochloraz EW in Ginger

[Objective]The paper was to evaluate the safety of 45%prochloraz EW in ginger,and to study the residue and degradation of 45%prochloraz EW in ginger.[Method]45%Prochloraz EW was sprayed once at the dose of 455.625 g a.i./ha in dynamic degradation test,and ginger plants were collected at 2 h,1,3,5,7,14,21,28,35 and 42 d post spraying,respectively.45%Prochloraz EW was sprayed at the doses of 303.75 and 455.625 g a.i./ha for 2-3 times with an interval of 7 d in final residue test,and ginger plants were collected at 7,14 and 21 d post spraying,respectively.The content of prochloraz was quantitatively analyzed by gas chromatography.[Result]Dynamic degradation test demonstrated that prochloraz degraded quickly in plants,and the half-life in Shandong and Anhui were 5.8 and 7.9 d,respectively.The final residue of prochloraz in ginger samples was<0.01-0.145 mg/kg,lower than the maximum residue limit of prochloraz in ginger formulated by European Union(0.2 mg/kg).[Conclusion]Prochloraz should be sprayed at the recommended dose of 202.5-303.75 g a.i./ha for prevention and control of anthracnose on ginger.The agent should be sprayed twice in the early stage of incidence,with an interval of 7 d,and the safety interval of 14 d was safe.

Preservation Effect of Prochloraz-manganese Chloride Complex on Postharvest ‘Shatangju'( Citrus reticulata)Fruits

[ Objective ] The paper was to solve the weakness of heavy postharvest diseases and non-endurable storage of ＇ Shatangju＇, to improve the preservation effect of ＇ Shatangju＇. [ Method ] Fruits were dipped in different concentrations of procbloraz-manganesc chloride complex solutions. The postharvest weight loss rate, soluble solids content and decay rate of fruits were determined, and the safety of chemical agents was observed and evaluated. [ Result ] Prochloraz-manganese chloride complex had significant preservation effect on postharvest ＇ Shatangju＇ fruits, and the appropriate concentration was 0.15% -0.20% （effective content） ; the decay rates of fruits stored at room temperature for 15, 30, 45, 60 and 90 d were 0, 5%, 〈 10%, 〈 10% and 〈 30% ; there was no specific changes in smell and flavor of non-decayed fruits. [ Conclusion ] Prochloraz-manganese chloride complex solution had significant preservation effect on ＇ Shatangju＇ by inhibiting and reducing the growth and development of pathogenic bacteria, and the effect was much better under refrigeration condition.

Inhibition Effect and Synergistic Effect of Prochloraz and Tebuconazole and Their Mixture on Fusarium graminearum

Wheat scab caused by Fusarium graminearum is increasingly severe in the middle and lower reaches of the Yangtze River region. With long-term use of single chemical pesticide,the drug resistance of F. graminearum is growing day by day. In order to reveal the inhibition effect and synergistic effect of prochloraz and tebuconazole and their mixture on F. graminearum,new compound agents for controlling wheat scab were developed. The inhibition effect and synergistic effect of prochloraz and tebuconazole mixed at seven different ratios on F. graminearum were studied. The results showed that the efficiency of the mixture was the best when the proportion of prochloraz and tebuconazole was 1:7; the EC50 was 0.145 36 and the synergistic coefficient was 1.853 9. The results provide a theoretical basis for development of new compound agents and effective control of wheat scab.

Preservation Effect of Prochloraz-manganese Chloride Complex on ‘Gonggan’ (Citrus reticulata) Fruits

‘Gonggan’( Citrus reticulata) is a famous,high-quality and special citrus cultivar in the Xijiang River valley,Guangdong Province. However,it easily suffers from postharvest diseases,and thus is not tolerant to storage. Based on the preliminary test results,prochloraz-manganese chloride complex was selected as the disinfectant,and prepared into different concentrations for carrying out preservation test by dipping fruits. The fruit weight loss,soluble solids content and decay rate were analyzed,and the application security and sensory evaluation for fruit freshness and flavor were observed. The results showed that dipping fruits with prochloraz-manganese chloride complex solution had significant preservation effect on‘Gonggan’fruits in postharvest storage; the suitable concentration was 2. 0-3. 0 g/L,and the decay rates of fruits stored at room temperature for 30,60 and 90 d were below 5%,10% and 15%,respectively. Plate inoculation test further revealed that the pathogen of‘Gonggan’was sensitive to prochloraz-manganese chloride complex,and the concentration of 1. 0 g/L was enough to produce significant antimicrobial effect. Other technical links related to postharvest preservation of‘Gonggan’with prochloraz-manganese chloride complex were discussed.

Application of Prochloraz-nano-titanium Dioxide Complex Fresh-keeping Agent in Refrigeration of Dioscorea alata Lirm. sp.

Prochloraz diluents( 450 ×,475 ×,500 ×) were added with different concentrations of nano-titanium dioxide( Ti O2)( 0. 8%,1. 0%) respectively to prepare complex fresh-keeping agents,which were applied in the refrigeration of Dioscorea alata Lirm. sp. With rot index,weight loss rate,browning degree( BD),total soluble solids( TSS) content,malondialdehyde( MDA) content,polyphenol oxidase( PPO) activity and peroxidase( POD) activity,DPPH· scavenging rate as evaluation indexes,the preservation effect of the prepared freshkeeping agents on D. alata during the cold storage period was analyzed. The results showed that prochloraz added with nano-titanium dioxide significantly prolonged the storage life,reduced the rot rate and weight loss rate,and slowed the loss of pulp of D. alata. The preservation effect of complex fresh-keeping agent of prochloraz diluent( 475 ×) and nano-titanium dioxide( 1. 0%) was better than that of other treatments.

抑霉唑、咪鲜胺及其代谢物在荔枝贮藏保鲜中的残留动态及安全评价

为评估抑霉唑和咪鲜胺在荔枝全果、果皮和果肉的残留情况及膳食风险,本研究建立了同时测定抑霉唑、咪鲜胺及其代谢物含量的气相色谱-串联质谱法。该方法检测抑霉唑、咪鲜胺、咪唑乙醇和2,4,6-三氯苯酚的方法检出限(LOD)分别为2.0、3.0、6.0、0.3μg/kg;定量限(LOQ)分别为6.0、10.0、20.0、1.0μg/kg;在荔枝全果、果皮和果肉中的添加回收率为78.9%~107%、RSD为2.6%~5.8%。保鲜实验结果表明,抑霉唑、咪鲜胺浸果浓度越高残留量越高,残留物随贮藏时间延长由果皮逐渐迁移到果肉中。全果和果皮中抑霉唑、咪鲜胺的残留量随贮藏时间延长不断降低,果肉则于浸泡后第7 d达到最大值再逐渐消解。代谢咪唑乙醇和2,4,6-三氯苯酚随着贮藏时间增加不断升高。用质量浓度为500 mg/L的抑霉唑、咪鲜胺溶液分别浸泡保鲜,安全间隔期14 d内荔枝咪鲜胺的慢性、急性膳食摄入风险在可接受的范围内。

异菌脲、咪鲜胺及其代谢物在哈密瓜贮藏保鲜中的降解动态及安全评价

目的评价哈密瓜贮藏过程中异菌脲、咪鲜胺及其代谢物2,4,6-三氯苯酚的残留消解动态,评估其人体慢性膳食摄入风险。方法采用气相色谱-串联质谱法(gas chromatography-tandem mass spectrometry,GC-MS/MS)检测哈密瓜在冷藏和常温贮藏条件下异菌脲、咪鲜胺和2,4,6-三氯苯酚随贮藏期延长残留量的变化,并对膳食摄入风险进行评估。结果异菌脲、咪鲜胺在哈密瓜中的消解动态均满足一级反应动力学方程,异菌脲在常温和冷藏条件下半衰期分别为3.3、3.6 d;咪鲜胺在常温和冷藏条件下半衰期分别为3.8、4.5 d。咪鲜胺的代谢物2,4,6-三氯苯酚在贮藏期间含量呈现增加趋势。一般人群对哈密瓜中实验农药的慢性膳食摄入的风险都较低,为可接受水平。结论本研究通过对哈密瓜中异菌脲、咪鲜胺及其代谢物贮藏保鲜过程中降解动态的研究,为合理规范使用杀菌剂提供了科学依据。

咪鲜胺对沃柑早采果贮藏品质的聚类分析

为了探索沃柑果实免遭霜冻害的方法,以2021—2022年提早采收的沃柑为材料,在室温贮藏条件下,采用咪鲜胺处理,以清水为对照(CK),测定各处理在贮藏期的糖、酸、维生素C等品质指标,以及失重率、腐烂率、电导率等耐贮性指标,并利用SPSS分析软件对2 a的7个指标进行聚类分析。结果表明:咪鲜胺能有效抑制沃柑贮藏期腐烂病菌的生长,延迟果实腐烂发生的时间;同时果实可溶性固形物含量能够维持在采前水平。在150 d贮藏期内,可滴定酸含量整体上随贮藏时间的延长逐渐下降,咪鲜胺处理的可滴定酸含量下降速度较CK快,因此,咪鲜胺处理的固酸比高于CK。固酸比随贮藏时间的延长而提高,风味物质含量也逐渐提升。在贮藏期间,咪鲜胺处理与CK的维生素C含量无显著差异,到贮藏150 d时,2021年的维生素C含量约20.90 mg/100 g,2022年约14.50 mg/100 g。在果实耐贮性方面,2022年咪鲜胺处理的失重率略低于CK,而2021年显著低于CK;2021年咪鲜胺处理的果皮电导率显著高于CK。通过聚类分析,将2 a的7个指标聚为2类,第一类为0、15、30、45、60、90 d的CK和0、15、30、45、60、90 d的咪鲜胺处理;第二类为120、150 d的CK和90、120、150 d的咪鲜胺处理。综上,咪鲜胺处理能有效降低沃柑腐烂率的发生,并能提高早采果的果实风味,同时也能维持果实较好的可溶性固形物、维生素C含量等。综合各项指标和聚类分析结果认为,沃柑可进行提早采收,经咪鲜胺等保鲜剂处理后,可在室温条件下贮藏60 d或60 d后进行低温冷藏,或室温贮藏90 d后出库上市。

高效杀菌剂农药咪鲜胺铜盐的绿色合成工艺

探索高效杀菌剂咪鲜胺铜盐的绿色合成工艺。以咪鲜胺为初使原料,经过络合、结晶、过滤、烘干四步反应得到目标化合物,总收率98.0%。咪鲜胺铜盐的合成路线未见文献报道,该工艺反应条件温和,收率高、生产成本低,适合工业化生产的绿色工艺。

40%咪鲜胺铜盐·氟环唑悬浮剂分析方法

咪鲜胺是一种广谱杀菌剂,对多种作物由子囊菌和半知菌引起的病害具有明显的防效,也可以与大多数杀菌剂、杀虫剂、除草剂混用,均有较好的防治效果。本文针对40%咪鲜胺铜盐与氟环唑悬浮剂的分析方法进行研究,最终以乙腈:水为流动相,用Eclipse Plus-C_(8)4.6×250 mm,5μm色谱柱和紫外检测器(波长270 nm),外标法定量,对试样中氟环唑与咪鲜胺同时进行高效液相色谱分析并进行验证,具有良好的专属性、线性关系、准确度及精密度,大大节约了分析成本及时间。

同位素稀释高分辨气相色谱-高分辨质谱法测定咪鲜胺原药中17种二噁英类化合物

建立同位素稀释高分辨气相色谱-高分辨质谱法测定咪鲜胺原药中二噁英类化合物的含量。样品经正己烷-二氯甲烷混合溶剂(体积比为5∶1)溶解后用酸化硅胶提取,采用多层硅胶柱与活性炭硅胶柱组合方式净化,用高分辨气相色谱-高分辨双聚焦磁质谱联用仪对17种二噁英类化合物进行分析,以同位素内标法定量。17种二噁英类化合物的质量浓度在一定范围内线性关系良好,相关系数为0.9997~0.9999。咪鲜胺原药中二噁英类化合物的检出限为0.01~0.1 ng/kg,测定结果的相对标准偏差为4.3%~13.6%(n=6),样品加标平均回收率为76.2%~115.8%。该方法实用性强、选择性好、灵敏度高,可用于咪鲜胺原药中二噁英类化合物的定量检测。

沃柑早采果室温贮藏品质分析

为了研究沃柑免受低温冻害问题,以八成熟的沃柑为研究对象,利用咪鲜胺、抑霉唑两种杀菌剂对其进行保鲜处理,清水作对照,于室温贮藏150 d,测定各处理在贮藏期间的品质指标以及腐烂率、失重率等耐贮性指标的变化,并用SPSS软件对不同处理进行主成分分析和聚类分析。结果表明:咪鲜胺、抑霉唑2个处理的可溶性固形物含量在贮藏期结束时均能维持在采前水平,在贮藏第150 d时表现为抑霉唑处理(13.70%)>对照(12.97%)>咪鲜胺处理(12.20%);随着贮藏时间的延长,果实可滴定酸含量均逐渐下降,至贮藏结束时,咪鲜胺、抑霉唑处理的可滴定酸含量由采前的0.83%分别下降到0.32%、0.36%(对照为0.36%);固酸比随着可滴定酸含量的降低而逐渐上升,果实品质也逐渐提升。与对照相比,咪鲜胺、抑霉唑处理均能有效降低沃柑早采果贮藏期的腐烂率(3.33%),而对照果实腐烂率为6.67%,并能延迟果实发生腐烂的时间。2个处理对果实失重率均无显著影响。主成分分析结果显示,在室温贮藏90 d后咪鲜胺、抑霉唑处理的果实风味品质逐渐变好。聚类分析结果显示,当欧氏距离为20时,所有处理(咪鲜胺贮藏90 d除外)的品质指标和耐贮性指标在贮藏0、15、30、45、60、90 d聚为第一类;在贮藏120、150d(含咪鲜胺贮藏90 d)聚为第二类。综合上述各项指标分析结果认为,沃柑可提前于12月底采收,且用咪鲜胺或抑霉唑等保鲜剂处理效果较好。

38%咪铜·多菌灵悬浮剂分析方法研究

采用高效液相色谱法,以乙腈-乙酸铵水溶液为流动相,Eclipse XDB-C84.6 mm×250 mm、5μm色谱柱和紫外检测器(235 nm),对试样中的咪鲜胺与多菌灵进行分离和定量。结果表明:该分析方法对于咪鲜胺铜盐、多菌灵的线性相关系数分别为0.9993、0.9998,标准偏差分别为0.10%、0.03%,变异系数分别为0.36%、0.40%,平均回收率分别为99.6%、99.5%。该分析方法具有操作简单、快速等优点,并且能同时检测2种有效成分,大大减少了分析的时间及成本。

气相色谱法测定山药中咪鲜胺及其代谢物的残留量

建立了检测山药中咪鲜胺及其代谢物2,4,6-三氯苯酚的气相色谱法。山药使用丙酮和正己烷(1+1)提取,浓缩后加入吡啶盐酸盐在(220±10)℃水解,用石油醚(Ⅰ)提取,浓硫酸净化后上机测定。该方法的线性范围为0.5~10.0μg·mL-1,最低检测浓度为0.005 mg·kg^(-1),在低、中、高3个加标水平下回收率为82.0%~91.6%,相对标准偏差为1.5%。该方法具有快捷、安全,可批量检测山药中咪鲜胺药物残留量。

45%戊唑醇·咪鲜胺水乳剂对苹果炭疽病的田间防治效果

为了丰富苹果炭疽病用药种类,加强药剂轮换,降低抗药性风险,2020~2021年采用田间试验方法,以430 g/L戊唑醇悬浮剂3000倍液(有效成分用量143.3 mg/kg)、45%咪鲜胺水乳剂1000倍液(有效成分用量450 mg/kg)和80%福·福锌可湿性粉剂500倍液(有效成分用量1600 mg/kg)为药剂对照,以清水处理为空白对照(CK),对45%戊唑醇·咪鲜胺水乳剂2000倍液、1500倍液和1000倍液(对应的有效成分用量分别为225、300和450 mg/kg)处理的苹果炭疽病防治效果进行了评价。结果表明:试验用量条件下,45%戊唑醇·咪鲜胺水乳剂对苹果炭疽病的防效较好,其中1000倍液和1500倍液处理的防效均超过90%,二者差异不显著;2000倍液处理的防效接近90%。45%戊唑醇·咪鲜胺水乳剂3种用量处理的防效均高于430 g/L戊唑醇悬浮剂和45%咪鲜胺水乳剂2种单剂处理。45%戊唑醇·咪鲜胺水乳剂2000倍液的防效与防治苹果炭疽病常用药剂80%福·福锌可湿性粉剂500倍液的防效相当;而1000倍液和1500倍液的防效高于80%福·福锌可湿性粉剂500倍液。45%戊唑醇·咪鲜胺水乳剂各用量处理均未观察到药害发生,对有益生物无不良影响。推荐使用45%戊唑醇·咪鲜胺水乳剂防治苹果炭疽病,有效成分用量225~300 mg/kg为宜,可大面积推广应用。

咪鲜胺及其代谢物在芹菜和生姜中的残留行为及膳食风险评估

为研究咪鲜胺及其代谢物在芹菜和生姜中的残留行为及膳食摄入风险,开展咪鲜胺及其代谢物在芹菜和生姜上的1年6地规范残留试验,气相色谱法(GC-ECD)分析样品,采用农药残留联席会议的方法评价咪鲜胺及其代谢物在芹菜和生姜中的膳食摄入风险。在咪鲜胺的添加水平为0.02、0.1、1 mg/kg时,咪鲜胺在姜上的平均回收率为77%~87%,相对标准偏差为3%~13%。在咪鲜胺添加水平为0.05、0.5、1、10 mg/kg时,咪鲜胺在芹菜上的平均回收率为75%~114%,相对标准偏差为3%~6%。咪鲜胺在芹菜中的半衰期为6.1~6.8 d。一般人群对咪鲜胺的国家估算每日摄入量(NEDI)为0.67331 mg,膳食摄入风险概率为106.9%。试验结果显示,咪鲜胺及其代谢物在中国普通人群的膳食摄入风险不在可接受范围内,本试验为咪鲜胺的合理使用、科学监管及制定咪鲜胺在芹菜和生姜上的最大残留限量(MRL)标准提供试验数据依据。

基于表面增强拉曼光谱技术的柑橘表皮咪鲜胺和抑霉唑农药残留检测

咪鲜胺和抑霉唑是柑橘类水果常用的保鲜剂,二者混用可有效降低致病细菌抗药性,达到更好的保鲜效果,但农残过量会影响食用者健康。基于表面增强拉曼光谱技术,以丑橘为基质,咪鲜胺和抑霉唑混合农药为研究对象,结合化学计量学方法,建立一种快速准确检测柑橘表皮农药残留的方法。为了对比金、银溶胶的增强效果,分别将金、银溶胶用于浓度为10 mg·L^(-1)的咪鲜胺、抑霉唑标准溶液及橘皮萃取液中的混合农药,采集其拉曼光谱。结果表明,咪鲜胺和抑霉唑的单独标准溶液中金溶胶较优,在橘皮萃取液中的混合农药溶液中银溶胶效果更佳。为了获得最佳增强效果,通过不同比例试验对比,最终确定溶胶增强基底与两种农药标准溶液体积比为1∶1,团聚剂NaCl浓度为1 mol·L^(-1)。按照浓度从高到低的方向,分别采集咪鲜胺标准溶液及抑霉唑标准溶液在不同浓度情况下的光谱,检出限分别低于1和0.5 mg·L^(-1),达到国标规定的最大残留限5 mg·L^(-1)。在咪鲜胺和抑霉唑混合农药的定量分析实验中,以橘皮萃取液为基质,用增强效果较好的银溶胶作为增强基底,采集含有梯度浓度的咪鲜胺和抑霉唑混合农药(5~42 mg·L^(-1))的表面增强拉曼光谱,采用多种预处理方法优化光谱数据,对比支持向量回归(SVR)、灰狼算法优化的支持向量回归(GWO-SVR)、粒子群算法优化的支持向量回归(PSO-SVR)、遗传算法优化的支持向量回归(GA-SVR)四种回归模型的建模效果选择最佳算法建立定量模型。结果表明:通过一阶微分预处理方法,选取829和1168 cm^(-1)处的特征峰强度建立灰狼算法优化的支持向量机回归(GWO-SVR)模型得到的预测效果最佳,其校正相关系数(R_(C))为0.978,校正集均方根误差(RMSEC)为1.655 mg·L^(-1),预测相关系数(R_(P))为0.967,预测集均方根误差(RMSEP)为2.227 mg·L^(-1)。研究结果表明,该方法可对柑橘表皮咪鲜胺和抑霉唑混合农药进行定性与定量检测,可为柑橘农残检测提供新思路。