Strawberry wilt disease, caused by Fusarium oxysporum f. sp. fragariae (Fof) results in a considerable decline in both strawberry yield and quality. Fludioxonil, a phenylpyrrole-class fungicide, is widely recognized for its effective control against various fungal pathogens. However, its specific activity against Fof has been insufficiently investigated. In this study, we assessed the antifungal activity of fludioxonil against Fof by determining the EC50 values for 100 Fof strains. The average EC50 value was 0.0239 ± 0.0032 μg/mL, indicating strong antifungal activity, which was further supported by a unimodal distribution of the EC50 values. Furthermore, eight highly resistant mutants were generated through in vitro fungicide taming. These mutants exhibited reduced biological fitness, as evidenced by diminished sporulation capacity and attenuated virulence. Under fludioxonil treatment, sensitive strains showed a significant increase in intracellular glycerol accumulation, whereas no significant change was observed in the resistant mutants. Moreover, the resistant mutants showed heightened sensitivity to hyperosmotic stresses. No cross-resistance was observed between fludioxonil and other fungicides with distinct modes of action, including phenamacril, carbendazim, pydiflumetofen, pyraclostrobin, tebuconazole, and fluazinam. Moreover, the phosphorylation level of FoHog1 was significantly lower in the resistant mutants compared to the sensitive strains. Mutations in key components FoOs1, FoOs5, and FoOs2 in the MAPK cascade pathway were identified in the resistant mutants. Based on these findings, we conclude that the risk of resistance development in Fof toward fludioxonil can be classified as low to moderate.

Fusarium head blight (FHB), primarily caused by the Fusarium graminearum species complex (FGSC), reduces cereal yields and causes substantial economic losses globally. In China, Fusarium asiaticum is the predominant FGSC species, causing yield losses and deoxynivalenol contamination. Pydiflumetofen, a succinate dehydrogenase inhibitor, was widely used in China for FHB control. Among 5176 field isolates collected in 2023 from Hubei, Anhui, and Jiangsu provinces, five pydiflumetofen-resistant F. asiaticum isolates were identified. These isolates exhibited reduced sporulation and virulence. Site-directed mutagenesis confirmed that the FaSDHC2-A83V substitution conferred high resistance while impairing sporulation. No cross-resistance occurred with pyraclostrobin, phenamacril, or tebuconazole, but strong positive cross-resistance was observed with fluopyram and enpyracymid, and negative cross-resistance with benzovindiflupyr, a novel finding with potential implications for agricultural and clinical antifungal strategies. This study reports the first field-derived pydiflumetofen-resistant F. asiaticum mutants and identifies FaSDHC2-A83V as a key resistance marker, aiding monitoring and sustainable FHB management.

Fusarium head blight (FHB), caused by the Fusarium graminearum species complex, poses a significant threat to global wheat production and human health due to its high virulence and the ability to produce harmful secondary metabolites. Although various fungicides have been extensively used to control FHB, there is a critical need for more comprehensive information on the resistance of F. graminearum to fluopyram in China. This study evaluated the sensitivity of F. graminearum strains collected from five distinct regions to fluopyram. The EC50 values for fluopyram ranged from 1.20 to 6.42 μg/mL, with an average value of 3.30 μg/mL. Additionally, fluopyram-resistant mutants were generated in the laboratory by chemical taming, with a resistance frequency of 8.3 × 10--3. Furthermore, no significant differences were observed in conidiation, growth rate, and temperature sensitivity between the resistant mutants and the parental strains. It was also determined that fluopyram exhibits positive cross-resistance with pydiflumetofen but no cross-resistance with carbendazim, tebuconazole, and pyraclostrobin. The mutations associated with fluopyram resistance in F. graminearum were identified as SDHB-H248L, SDHC2-A83V, and SDHC2-R86K. Based on these findings, the risk of resistance development in F. graminearum to fluopyram was assessed as moderate. Additionally, it was found that the combination of prothioconazole and fluopyram is more effective than their individual use in field trials. Considering the role of fluopyram in inhibiting DON produced by F. graminearum, it is recommended that fluopyram be used in conjunction with other highly effective fungicides to control FHB, thereby achieving both disease control and mycotoxin reduction.

Tomato wilt disease caused by Fusarium oxysporum f. sp. lycopersici (Fol) results in a decrease in tomato yield and quality. Pyraclostrobin, a typical quinone outside inhibitor (QoI), inhibits the cytochrome bc1 complex to block energy transfer. However, there is currently limited research on the effectiveness of pyraclostrobin against Fol. In this study, we determined the activity of pyraclostrobin against Fol and found the EC50 values for pyraclostrobin against 100 Fol strains (which have never been exposed to QoIs before). The average EC50 value is 0.3739 ± 0.2413 μg/mL, indicating a strong antifungal activity of pyraclostrobin against Fol, as shown by unimodal curves of the EC50 values. Furthermore, we generated five resistant mutants through chemical taming and identified four mutants with high-level resistance due to the Cytb-G143S mutation and one mutant with medium-level resistance due to the Cytb-G137R mutation. The molecular docking results indicate that the Cytb-G143S or Cytb-G137R mutations of Fol lead to a change in the binding mode of Cytb to pyraclostrobin, resulting in a decrease in affinity. The resistant mutants exhibit reduced fitness in terms of mycelial growth (25 and 30 °C), virulence, and sporulation. Moreover, the mutants carrying the Cytb-G143S mutation suffer a more severe fitness penalty compared to those carrying the Cytb-G137R mutation. There is a positive correlation observed among azoxystrobin, picoxystrobin, fluoxastrobin, and pyraclostrobin for resistant mutants; however, no cross-resistance was detected between pyraclostrobin and pydiflumetofen, prochloraz, or cyazofamid. Thus, we conclude that the potential risk of resistance development in Fol toward pyraclostrobin can be categorized as ranging from low to moderate.

Gray mould caused by Botrytis cinerea poses a threat to Lily (Lilium spp.), an important plant with both medicinal and ornamental value, during pre- and post-harvest stages. Ergosterol biosynthesis inhibitors (EBIs) have been widely registered to control gray mould caused by B. cinerea in various plants over a prolonged period of time, yet no instances of resistance of B. cinerea to EBIs have been detected in the field. In this study, the field B. cinerea EBIs-resistant populations were detected from the diseased lily flowers. The CYP51 protein, which is the target of EBIs, was found to have G461S or R464K substitutions in these resistant strains. To further verify whether the G461S or R464K substitutions of CYP51 confer the resistance to EBIs in B. cinerea, the mutants carrying the G461S or R464K substitutions of CYP51 were generated from EBIs-sensitive wild type strains via site-directed mutagenesis. The G461S or R464K substitutions indeed resulted in decreased sensitivity of B. cinerea to EBIs. Meanwhile, the mutants conferring the S461G or K464R substitutions of CYP51 were generated from the field EBIs-resistant strains, and the significant increase in sensitivity to EBIs were observed in these mutants. Furthermore, the G461S or R464K substitutions suffered to fitness penalty in mycelial growth and virulence, but improved sporulation capability. Molecular docking analysis furtherly demonstrated that the CYP51 protein, carrying the G461S or R464K substitutions, exhibited reduced binding affinity with tebuconazole. To the best of our knowledge, it is the first report that G461S or R464K substitutions in CYP51 leading to field resistance to EBIs in B. cinerea. These findings not only provided valuable insights for managing lily gray mould caused B. cinerea, but also enhance our understanding of molecular mechanism underlying plant pathogen resistance to EBIs.

Fusarium solani is responsible for causing root rot in various crops, resulting in wilting and eventual demise. Phenamacril, a specific inhibitor of myosin5 protein, has gained recognition as an effective fungicide against a broad spectrum of Fusarium species. It has been officially registered for controlling Fusarium diseases through spray application, root irrigation, and seed dipping. In this study, phenamacril was observed to exhibit negligible inhibitory effects on F. solani causing crop root rot, despite the absence of prior exposure to phenamacril. Considering the high selectivity of phenamacril, this phenomenon was attributed to intrinsic resistance and further investigated for its underlying mechanism. Sequence alignment analysis of myosin5 proteins across different Fusarium species revealed significant differences at positions 218 and 376. Subsequent homology modeling and molecular docking results indicated that substitutions T218S, K376M, and T218S&K376M impaired the binding affinity between phenamacril and myosin5 in F. solani. Mutants carrying these substitutions were generated via site-directed mutagenesis. A phenamacril-sensitivity test showed that the EC50 values of mutants carrying T218S, K376M, and T218S&K376M were reduced by at least 6.13-fold, 9.66-fold, and 761.90-fold respectively compared to the wild-type strain. Fitness testing indicated that mutants carrying K376M or T218S&K376M had reduced sporulation compared to the wild-type strain. Additionally, mutants carrying T218S exhibited an enhanced virulence compared to the wild-type strain. However, there were no significant differences observed in mycelial growth rates between the mutants and the wild-type strain. Thus, the intrinsic differences observed at positions 218 and 376 in myosin5 between F. solani and other Fusarium species are specifically associated with phenamacril resistance. The identification of these resistance-associated positions in myosin5 of F. solani has significantly contributed to the understanding of phenamacril resistance mechanisms, thereby discouraging the use of phenamacril for controlling F. solani.

为筛选出有效防治桃褐腐病的高效杀菌剂,选择申嗪霉素、咪鲜胺、苯醚甲环唑、腈苯唑4种药剂进行田间小区防治试验.田间试验表明,申嗪霉素、咪鲜胺、苯醚甲环唑、腈苯唑对桃果实褐腐病都有一定的田间和采后防效,药后14d(采摘前),1％申嗪霉素悬浮剂500倍液和24％腈苯唑悬浮剂2 500倍液对桃褐腐病的病果率防效均为100％,显著高于450 g/L咪鲜胺水乳剂1 000倍液和10％苯醚甲环唑水分散粒剂1 000倍液的87.33％和86.93％防效;采后18d,1％申嗪霉素悬浮剂500倍液、450 g/L咪鲜胺水乳剂1 000倍液和10％苯醚甲环唑水分散粒剂1 000倍液对褐腐病果率仍有较好的防效,防效为71.25％～80.83％,其次是24％腈苯唑悬浮剂2 500倍液,防效为62.83％.综上,4种药剂都有控制桃褐腐病病果的应用潜力,其中申嗪霉素表现出较好的田间和采后防效.

为研究虫酰肼在菠菜和芹菜中的残留及消解动态,并进行膳食风险评估,建立基于高效液相色谱串联质谱(UPLC-MS/MS)测定菠菜和芹菜中虫酰肼残留的分析方法,样品经乙腈提取,石墨化碳黑(GCB)净化,UPLC-MS/MS检测.在0.001～1.000 mg/L范围内,虫酰肼质量浓度与其峰面积呈良好的线性关系,决定系数大于0.999.在0.01～20.00 mg/kg添加水平下,虫酰肼在菠菜和芹菜中的平均回收率为90.0％～100.8％,相对标准偏差(RSD)为1.4％～5.6％,定量限均为0.01 mg/kg.虫酰肼在菠菜和芹菜中的消解符合一级动力学方程,半衰期分别为2.9～4.5 d和2.4～13.1 d.施药后5 d,虫酰肼在菠菜和芹菜中的最终残留量分别为1.00～7.40 mg/kg和0.70～8.94 mg/kg;施药后7d,菠菜和芹菜中虫酰肼的最终残留量分别为0.76～6.18 mg/kg和0.67～7.68 mg/kg.其最终残留量均低于我国规定的叶菜类蔬菜中虫酰肼的最大残留限量(10 mg/kg).菠菜和芹菜中虫酰肼的急性膳食摄入风险商(RQa)为10.7％～37.8％,慢性膳食摄入风险商(RQc)为12.5％～39.0％.虫酰肼的急性和慢性膳食摄入风险商均小于100％,表明虫酰肼的残留量不会对人群健康造成不可接受的风险.

[目的]研究桑葚菌核病发生规律,探索防控药剂的应用技术.[方法]病原鉴定采用基因测序和形态学鉴定法,田间防效采用喷雾法,植物安全性采用生长速率测定法,药剂残留检测采用液相色谱-串联质谱分析法.[结果]病原鉴定结果表明:江苏、江西和四川试验地采集的桑葚菌核病病原均为核地仗菌.7个药剂筛选和啶酰菌胺农药登记试验表明:在桑葚初花期(开花量5％)施药,啶酰菌胺对桑葚菌核病的田间防效为71％～95％,在江苏省试验中其防效超过85％.植物安全性试验表明:啶酰菌胺在416.65、833.3、1250、1666.6 g a.i./hm2剂量下,对桑葚安全且能促进桑葚幼苗新枝生长.农药残留试验结果表明:50％啶酰菌胺水分散粒剂600倍液施药2次在桑葚中安全间隔期为7 d,残留值低于国家标准,膳食风险可接受.[结论]啶酰菌胺可作为防治桑葚菌核病的优选药剂.

为了探索防治月季二斑叶螨的理想药剂,本文研究了螺螨酯和乙螨唑2种杀螨剂对月季二斑叶螨的室内活性和田间药效.结果表明,螺螨酯和乙螨唑对月季二斑叶螨成虫和卵的LC50/EC50值分别为11.350～14.152和0.019～0.035 mg/L,药后15 d田间防效在88.60％～94.11％之间.其防治效果随用药量增加而递增,且对月季安全.生产上可以推广应用螺螨酯和乙螨唑防治月季二斑叶螨,在害螨始盛期施药,间隔7～10 d,连续喷雾2次,可有效控制二斑叶螨对月季的危害.

为明确月季茎蜂在江苏省常州市内的发生规律,探索防控药剂的应用技术.结合本地区物侯规律调查月季茎蜂发生动态并用常规喷雾法开展田间试验,明确各药剂防治效果.调查结果显示,月季茎蜂在江苏常州1年发生1代,4月上中旬为雌虫产卵高峰,18～26℃温度条件下,晴天卵历期5～6d,阴天6～8d.1～3龄幼虫较为活跃,3龄幼虫后移动性逐渐变差.高龄幼虫一般在茎秆地下部分或较老茎秆内作茧越冬.田间筛选试验和农药登记试验表明,月季初见折梢时(一般4月中上旬)施用噻虫嗪67.5～90g/hm21次,防效超过80％且对月季植株安全.噻虫嗪可作为防治月季茎蜂的优选药剂.

本文研究了丁醚脲、噻虫嗪等11种杀虫剂对香葱蓟马的田间药效及其对香葱的作物安全性.结果表明,乙基多杀菌素、噻虫嗪和呋虫胺对香葱蓟马的防效较好,甲氨基阿维菌素苯甲酸盐和啶虫脒防效次之,试验药剂对香葱安全.结合残留风险控制指标,推荐使用25％噻虫嗪水分散粒剂75g/hm2(有效成分)和2％甲氨基阿维菌素苯甲酸盐乳油3g/hm2(有效成分)防控香葱蓟马,在香葱蓟马始盛期施药1次,安全间隔期为7d,可有效控制蓟马对香葱的危害.

蚜虫是金银花主要害虫之一,严重降低金银花品质,威胁产业发展.本研究通过1年3地田间药效试验和农药残留试验证实,50％吡蚜酮水分散粒剂能有效防治金银花蚜虫,膳食风险可接受,推荐使用有效剂量108～144g/hm2(制剂量14.4～19.2g/667m2),于金银花蚜虫发生始盛期施药1次,安全间隔期为14 d.

韭菜、豇豆和芹菜,即"三棵菜",是"菜篮子"中的重要农产品,深受城乡百姓喜欢,市场需求大,但近年来由于病虫害发生严重,加上超剂量、超范围和盲目用药等导致残留问题日益突出,严重威胁食品安全.为促进对"三棵菜"病虫害的了解,探索有效的防治方法,本文分析了"三棵菜"病虫害种类和农药登记现状,并针对病虫防控问题,提出加强基础规律研究、加快农药登记进程、建设智慧防控体系和创新推广模式等建议.

本文研究了吡蚜酮和吡虫啉2种杀虫剂对月季蚜虫的田间药效及其对月季的作物安全性.结果 表明,吡蚜酮和吡虫啉对月季蚜虫防效较好,药后7d防效在86.27％～99.03％之间.其防治效果随用药量增加而递增,且对月季安全.生产上应用吡蚜酮和吡虫啉防治月季蚜虫,在蚜虫始盛期发病初期施药1次,可有效控制蚜虫对月季的危害,对花农增收效果显著.

花卉疫病是由色菌界卵菌纲的疫霉菌引起的、危害花卉植物的一类病害,又称“花卉癌症”,严重制约花卉产业发展.为促进人们对花卉疫病的了解,探索有效防治方法,本文分析了花卉疫病危害、防控措施优缺点及疫病药剂登记现状,提出加强花卉疫病发生规律研究、加快农药登记和加速生物防治技术集成等建议.

本文研究了江苏省"十三五"期间农药登记的基本情况和特点.分析了五年内江苏省农药登记总体情况.分别对微毒/低毒农药、乳油/可湿性粉剂/悬浮剂/水分散粒剂/可分散油悬浮剂5种主要剂型、三大类农药和生物源农药的年度登记产品变化进行了分析.并基于数据分析结果和登记相关政策背景,对"十四五"期间江苏省农药登记及产业发展趋势进行了展望.

纹枯病是稻麦主要病害之一,为探究小盾壳霉制剂对稻麦纹枯病防治效果,本试验测定了小盾壳霉对立枯丝核菌和禾谷丝核菌的室内生物活性,并采用大田试验研究其对小麦纹枯病、水稻纹枯病的防效和增产率.室内生物活性(毒性)测试结果表明,小盾壳霉对禾谷丝核菌的校正腐烂率为86.7％,对立枯丝核菌的校正腐烂率为90％.2年田间试验结果表明,小盾壳霉在推荐剂量下防治稻麦纹枯病防效稳定在>90％.研究还发现,小盾壳霉对水稻、小麦有一定的增产作用,不同施药方式对防效无显著影响.

近年来,兴华芋头、无锡百合、宝应荷藕等一大批特色经济作物"小产业"给地方产业振兴"大格局"注入新的动力.但由于特经作物适用农药发展相对滞后,一定程度上影响了特经作物的高质量发展.2014～2019年,江苏特色作物适用农药筛选团队通过研发、应用特色作物农药残留控制技术,破除了特色经济作物农产品质量安全隐患制约,打造了特色作物产业高质量发展样板,获全国农牧渔业丰收奖一等奖,对建设"富强美高"新江苏具有重要的现实意义.

菊花白锈病是一种世界性病害,严重降低菊花观赏性,威胁菊花产业健康发展.为保障菊花产业健康发展,本论文通过2年田间试验验证300g/L苯醚甲环唑·丙环唑乳油、10％苯醚甲环唑水分散粒剂、250g/L丙环唑乳油、30％嘧菌酯悬浮剂和45％苯并·嘧菌酯水分散粒剂共5种药剂对菊花白锈病的防治效果.结果 表明:300g/L苯甲·丙环唑乳油和45％苯并·嘧菌酯水分散粒剂对菊花白锈病防治效果良好.因此,30g/L苯甲·丙环唑乳油和45％苯并·嘧菌酯水分散粒剂可作为防治菊花白锈病的优选药剂.