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。

Control Effect of 35% Thiamethoxam-prochloraz FS to Plant Diseases and Insect Pests at Rice Seedling Stage and Safety Evaluation

The prevention and control effect of 35% thiamethoxam-prochloraz FS to rice thrips and rice bakanae disease and its influence on the quality of rice seedlings were studied. The results show that when 100 kg of rice seeds were coated with 200 g of 35% thiamethoxam-prochloraz FS,the control effects to rice thrips were 93.0% and 84.7% 15 and 20 days after sowing, and the control effect to rice bakanae disease was 90.8% 30 days after sowing. As 100 kg of rice seeds were coated with 250 g of 35% thiamethoxam-prochloraz FS, the control effects to rice thrips were 98.2% and 94.9% 15 and 20 days after sowing, and the control ef- fect to rice bakanae disease was 94.6% 30 days after sowing. 35% thiamethoxam- prochloraz FS is safe to rice seedlings and can effectively promote the growth of rice seedlings.

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。

不同保鲜处理对青皮核桃贮藏品质的影响

为探究不同保鲜处理对青皮核桃贮藏效果的影响,该研究以青皮核桃为试验材料,采用4种不同保鲜方法进行处理:0℃冷水浸泡5 min、150 mg/L ClO_(2)浸泡20 min、100 mg/L赤霉素浸泡20 min和赤霉素(100 mg/L)+咪鲜胺(有效成分含量450 g/L)混合处理20 min,以不做处理的青皮核桃为对照,在0±0.3℃的低温条件下贮藏,研究其贮藏期间褐变指数、水分含量、色差、呼吸强度、硬度、叶绿素含量、丙二醛(malondialdehyde,MDA)含量、多酚氧化酶(polyphenol oxidase,PPO)和过氧化物酶(peroxidase,POD)活性,总酚和总黄酮含量。结果表明,在贮藏期间,处理组青皮核桃与对照组相比,处理组显著(P<0.05)延缓了其水分含量的降低和色差的变化,延缓褐变指数、呼吸强度和PPO活性的上升,抑制了硬度、叶绿素、总酚、总黄酮含量的下降,降低了贮藏期MDA的生成量,更好的保持POD活性。由试验可知,赤霉素+咪鲜胺处理的青皮核桃水分含量、硬度、叶绿素含量、总酚和总黄酮含量最高,褐变指数和色差上升最缓慢,呼吸强度最低,丙二醛含量和PPO、POD活性最低,保鲜效果最佳。

咪鲜胺和百可得对南丰蜜橘保鲜效果的协同效应

为探究咪鲜胺和百可得复配浸果对南丰蜜橘的保鲜效果,本研究采用咪鲜胺(P)、百可得(B)及“咪鲜胺+百可得”(PB)处理南丰蜜橘,以清水浸泡为对照(CK),分别在室温贮藏(R)及4℃冷藏(C)下,每隔7 d测定南丰蜜橘的腐烂率、失重率及内在品质指标。结果表明,与CK相比,贮藏期内P、B及PB处理后的腐烂率及失重率均显著降低,室温贮藏下腐烂率分别平均降低10.8、7.9及12.4个百分点,失重率分别平均降低8.1、6.3及7.2个百分点;而冷藏下腐烂率分别平均降低3.5、1.8及4.5个百分点,失重率分别平均降低4.0、1.1及5.2个百分点。室温下经P与B处理后,维生素C及可溶性固形物含量总体高于CK及PB处理;可溶性总糖含量、糖酸比及固酸比均表现为P处理最高、B处理较低,PB及CK处理介于二者之间;可滴定酸含量与可溶性总糖含量、糖酸比及固酸比的变化规律相反。冷藏条件下经P、B及PB处理后,内在品质指标的总体变化规律不明显。综上,室温贮藏或冷藏下单一使用咪鲜胺或百可得均能显著提升采后保鲜效果,二者结合使用可协同延长货架期,其中室温下单一使用咪鲜胺果品更佳,而冷藏下药剂处理对果品无不利影响。本研究为咪鲜胺和百可得的保鲜机理及南丰蜜橘采后保鲜研究提供了理论支持。

灭菌唑及其复配剂对河南省禾谷镰孢菌的抑制活性及对小麦赤霉病的室内防效

由禾谷镰孢菌(Fusarium graminearum)引起的赤霉病是小麦生产上的重要病害之一。为明确三唑类杀菌剂灭菌唑对禾谷镰孢菌的抑制活性,室内测定了禾谷镰孢菌不同发育阶段对灭菌唑的敏感性,发现其敏感性由低到高依次为:孢子萌发<芽管伸长<菌丝生长,EC_(50)值分别为18.16、1.332和0.4613μg/mL。采用菌丝生长速率法测定了从河南省9个地市采集分离的101株禾谷镰孢菌对灭菌唑的敏感性,结果显示:EC_(50)值范围在0.0586~0.9183μg/mL之间,平均值为(0.3866±0.1969)μg/mL,且敏感性频率分布呈连续单峰曲线,该平均EC_(50)值可作为河南省禾谷镰孢菌对灭菌唑的敏感性基线。灭菌唑分别与氟唑菌酰羟胺、多菌灵、咯菌腈、氰烯菌酯、咪鲜胺5种杀菌剂复配后,对禾谷镰孢菌的联合毒力测定结果表明:增效系数(SR)在0.53~3.76之间,不同组合、不同比例的复配剂均表现为相加或增效作用,其中咪鲜胺与灭菌唑按质量比1:3复配时,增效作用最明显(SR=3.76)。室内离体防治效果测定显示,在有效成分400μg/mL剂量下,咪鲜胺与灭菌唑质量比1:3复配剂的治疗作用防效最高,为82.63%。研究结果有助于指导灭菌唑的科学合理使用,并为小麦赤霉病的综合防控提供理论依据和数据支持。

芒果可可毛色二孢咪鲜胺抗药性菌株的转录组分析

为探析芒果可可毛色二孢对咪鲜胺的解毒代谢分子机制,挖掘相关功能基因。本研究使用RNA-seq技术对咪鲜胺处理和未处理的可可毛色二孢菌株进行转录组测序。结果表明:咪鲜胺对敏感菌株具有显著的抑制活性,半数有效浓度EC_(50)值为0.12 mg/L,2个抗性菌株的EC_(50)值分别为敏感菌株的7.67倍和32.67倍。对咪鲜胺敏感菌株(DF04)和抗性菌株(HL02、M108)间差异表达基因(DEG)进行GO功能富集和KEGG信号通路富集分析显示:与未用咪鲜胺处理(CK)相比,10 mg/L咪鲜胺处理后的DF04、HL02、M108菌株分别有5342、1148、2568个DEGs;其中,3个菌株之间共有566个DEGs重叠。与敏感菌株相比,抗性菌株分别有2078和3096个DEGs上调表达,1527和1793个DEGs下调表达。通过GO富集结果显示,咪鲜胺处理后的抗性和敏感菌株之间富集到细胞过程和代谢过程的DEGs最多,在HL02和M108中分别占比18%和16%、17%和15%。KEGG富集结果显示,咪鲜胺处理后抗性和敏感菌株之间DEGs显著富集在代谢通路中,HL02和M108中分别占比64.98%和63.39%。针对解毒代谢相关的DEGs的分析发现,抗性菌株中具有显著差异的细胞色素P450(Cytochrome P450)、谷胱甘肽转移酶(GST)和ABC转运蛋白(ABC transporter)基因分别为27、17、59个。随机筛选8个基因进行实时荧光定量验证,结果证实这些基因的相对表达量的变化趋势与转录组数据一致。根据抗敏菌株之间差异表达基因明显上调表达,共筛选出7个P450s基因、8个GSTs基因、11个ABC转运蛋白基因,可能与可可毛色二孢对咪鲜胺的代谢抗性机制有关。本研究结果为杀菌剂抗性机制提供新见解,也为深入探析咪鲜胺代谢抗性的分子机制奠定基础。

超高效液相色谱-串联质谱法测定水稻中咪鲜胺的残留总量

建立超高效液相色谱-串联质谱检测水稻中咪鲜胺残留总量的方法。水稻糙米、稻壳、秸秆样品采用乙腈提取,基质分散固相萃取净化,高温条件下盐酸吡啶催化生成2,4,6-三氯苯酚,经XR-ODSⅢ C_(18)超高效液相色谱柱分离,基质外标法定量。试验结果表明,在添加水平为0.05~5 mg/kg时,咪鲜胺的添加回收率为70%~84%,相对标准偏差为0~4.6%。方法的定量限(LOQ)为0.05 mg/kg。方法操作简便、精确、高效,适用于水稻样品中咪鲜胺农药残留的快速筛查和定量检测。

气相色谱法检测生姜贮藏期间咪鲜胺及其代谢物残留动态研究

为了确认采用气相色谱法检测生姜中咪鲜胺及其代谢物残留动态方法的准确性,并确定咪鲜胺对生姜贮藏保鲜作用的安全用量,试验在验证气相色谱法(ECD电子捕获检测器)测定衍生化后生姜样品中咪鲜胺残留量的分析方法的准确度和灵敏度的基础上,将经450mg/kg咪鲜胺处理后的生姜在低温条件下(12±1)℃贮藏,用气相色谱法检测咪鲜胺及其代谢物2,4,6-三氯苯酚的残留动态。结果表明:咪鲜胺的衍生化率在0.1~1.0mg/kg浓度下均为100%,采用气相色谱法检测生姜中咪鲜胺及其代谢物残留动态的方法简单有效,准确度和精确度较好,灵敏度较高,符合农药残留分析的基本要求。咪鲜胺在生姜贮藏过程中的残留消解较慢,姜皮中残留量随贮藏期延长呈下降趋势,贮藏期第42天时降至14.31mg/kg,在姜肉中总体表现为残留量先增加后降低的趋势,含量最大值在贮藏第35天,为0.31mg/kg,第42天后含量降至0.25 mg/kg;2,4,6-三氯苯酚在生姜不同组织中的含量变化整体呈上升趋势,贮藏期第28天时,姜皮、姜肉中含量分别为0.042、0.035mg/kg,残留量均小于0.1mg/kg,符合食品安全标准。因此,450 mg/kg浓度咪鲜胺处理可以作为生姜贮藏的防腐保鲜剂。

咪鲜胺及其代谢物三氯苯酚在百合植株中的残留检测方法及其动态研究

建立了QuEChERS前处理结合高效液相色谱-串联质谱(HPLC-MS/MS)的方法检测百合植株中咪鲜胺的残留量.同时,采用气相色谱(GC)对咪鲜胺的主要代谢产物三氯苯酚在百合植株中的残留情况进行了测定和分析.结果表明,添加量为0.01~0.5 mg/kg时,咪鲜胺和三氯苯酚在百合植株中的平均回收率分别为80.2%~87.8%和81.1%~105.5%, RSD分别为5.2%~6.7%和3.0%~8.4%.消解动态结果表明,咪鲜胺降解速度快、残留低,属于容易降解的农药,但施用后咪鲜胺很快转化为毒性更强的环境污染物2, 4, 6-三氯苯酚,这为咪鲜胺在百合上的安全使用提供了参考数据.

咪鲜胺对环境动物的毒理研究概述

咪鲜胺是一种新型咪唑类杀菌剂,主要登记用于农作物的病害防治和果蔬保鲜。但是,咪鲜胺作为一种类雌激素农药,其对非靶标环境动物具有一定毒性,除生殖影响外,还会对环境动物行为、蜕皮、免疫系统以及保护酶和解毒酶等方面产生影响。基于此,就这些方面的研究进行了评述,以期为咪鲜胺的安全使用提供参考。

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。