新奥霉素对7种植物病原真菌的室内毒力测定

[目的]新奥霉素是一种新开发的生物杀菌剂,为明确其对植物病原真菌的抑制活性,采用菌丝生长速率法测定了新奥霉素对7种植物病原真菌的毒力。[结果]新奥霉素对油菜菌核病菌、小麦纹枯病菌、稻瘟病菌、水稻纹枯病菌、小麦赤霉病菌、棉花黄萎病菌和苹果炭疽病菌的EC50值分别为2.61、27.36、63.26、131.64、168.04、421.02、546.51 mg/L。[结论]新奥霉素对植物病原真菌油菜菌核病菌和小麦纹枯病菌具有较强的毒力。     

紫穗槐协同杀虫成分分离及其毒力研究

通过对紫穗槐叶和茎成分分离,得到6a,12a-脱氢-α-灰叶酚、6a,12a-脱氢鱼藤素、(±)灰叶素、(-)6-羟基-6a,12a-脱氢灰叶酚4个化合物。对大皱腮金龟甲毒力试验表明,这4个化合物单独给药杀虫活性较弱,按1:2.54:4.18:2.54天然比例混配,表现出明显的协同增效作用,LC5013.4898mg.L-1,共毒系数2318。给药方式和溶剂类型对杀虫活性有显著影响,室外叶面喷雾法明显优于室内浸蘸法,吐温水乳剂效果优于氯仿溶液。     

苦葛藤提取物对玉米蚜虫的杀虫活性初报

[目的]通过研究苦葛藤对玉米蚜虫的杀虫活性,为新型植物源农药的开发提供依据.[方法]采用溶剂提取苦葛藤中的活性成分,以浸虫法测定苦葛藤的4种溶剂提取物对玉米缢管蚜的触杀活性.[结果]苦葛藤的几种溶剂提取物对玉米缢管蚜有明显的触杀活性.经125mg/L正丁醇提取物处理72 h后,玉米缢管蚜的校正死亡率达100％.[结论]苦葛藤正丁醇提取物对玉米缢管蚜有很强的触杀活性,其LD50值为14.55 mg/L,4种溶剂提取物杀虫活性的顺序为正丁醇提取物＞乙酸乙酯提取物＞石油醚提取物＞水提取物.     

25%敌氰乳油对蔬菜蚜虫的室内联合毒力测定

介绍２５％敌·氰乳油在蔬菜蚜虫作为供试虫进行了室内毒力测定,并对测试结果作了分析说明。     

噻虫啉对蚜虫杀虫活性及田间药效评价

采用农药生物测定标准操作程序(SOP)比较测定了噻虫啉和吡虫啉对蚜虫的毒力。室内生物测定结果表明,噻虫啉和吡虫啉对蚜虫有良好的杀虫活性,其毒力平均LC50分别为1.24mg/L和1.45mg/L。田间小区试验结果表明,噻虫啉对蚜虫表现出良好的防治效果,有效用量为3.36、6.72、10.08g/667m2时,药后1～10d的防治效果分别为85.82%～89.55%、89.25%～92.08%、92.43%～96.34%,好于剂量相当的吡虫啉的防治效果。     

25%敌氰乳油对蔬菜蚜虫的室内联合毒力测定

介绍２５％敌·氰乳油在蔬菜蚜虫作为供试虫进行的室内毒力测定,并对测试结果作了分析说明。     

砂仁炭疽病病原菌鉴定及杀菌剂毒力测定

从贵州省关岭县花江地区的砂仁叶片病斑上分离到1种炭疽病菌,根据病害症状特点、病菌形态特征、培养性状和致病性测定等进行鉴定,结果表明：病菌的无性世代为胶孢炭疽菌[Colletotrichum gloeosporioides（Penz．）Sacc．],有性世代为同小丛壳菌[Glomerella cingulata（Stonem．）Spaulding et Schrenk]。药剂毒力试验结果表明,对菌丝生长有较强抑制作用的药剂有70％甲基硫菌灵500μg／ml、10％苯醚甲环唑500μg／ml、50％氯溴异氰尿酸2000μg／ml,抑菌效果均达到90％以上;对孢子萌发抑制率达90％以上的药剂有70％甲基硫菌灵、10％苯醚甲环唑和50％氯溴异氰尿酸。     

我国杀虫微生物的应用研究进展及发展前景

微生物杀虫剂是目前生物农药产业的主要组成部分。本文分杀虫细菌,杀虫真菌,昆虫病毒三个部分,综合我国该领域近年的研究及应用开发概况,同时对其发展前景做了展望。     

一株蝗虫病原菌的分离鉴定及其毒力测定

从“细菌灭蝗剂”中分离纯化到蝗虫病原菌hb,通过16SrDNA序列分析和DNA同源性分析,结合生理生化测定结果,将菌株hb鉴定为产碱杆菌(Alcaligenes sp.)。通过口服感染测定了该菌对蝗虫的毒力,致死中浓度LC50为1.33×1011cfu/L。     

试谈新型杀虫化合物的生物活性测定

本文探讨了农药创制中新型杀虫化合物的生物测定存在的问题及解决途径,并对探索、建立新试验方法的必要性、部分高效筛选方法及存在问题做了概括说明.     

9种药用植物内生或附生真菌的分离及其杀虫、抑菌活性

从9种药用植物的根、茎、叶、花中分离得到358株内生或附生真菌,其中9株真菌的发酵液对白纹伊蚊3龄幼虫的毒杀活性较强,24 h死亡率均达到80%以上;15株真菌的发酵液对至少1种供试病原真菌的菌丝生长抑制率超过50%;4株真菌的发酵液对5种供试细菌均有明显的抑菌活性.     

侵染马铃薯块茎蛾幼虫的球孢白僵菌对桃蚜的毒力测定

室内测定了从罹病马铃薯块茎蛾Phthorimaea operculella(Zeller)幼虫上分离到的球孢白僵菌Beauveris bassiana两菌株(Bb001,Bb004)对甘蓝桃蚜Myzus persicae(Sulzer)的毒力。运用时间-剂量-死亡率模型,对死亡率随时间和剂量的变化趋势,以及两种菌株在不同温度下对桃蚜的毒力作了分析。结果表明：两种菌株对桃蚜均具有毒杀作用,菌株Bb004在21℃下表现了较高的毒力,菌株Bb001在21℃～28℃下对桃蚜均有较强的致病力,2l℃～25℃下是两菌株共同发挥毒力最佳的温度。其中,Bb001有较宽的适宜温度范围,而Bb004适宜温度范围较小。     

茜草中杀虫活性物质的分离及结构鉴定

在对茜草杀虫活性研究的基础上,通过杀虫活性跟踪分析和柱层析分离,从茜草石油醚萃取物中分离得到一种杀虫活性成分,经理化数据测试及UV、IR、MS、NMR等波谱分析及X射线单晶衍射分析,确定了该成分的结构,为一新的杀虫活性物质.     

氟啶虫胺腈对桃蚜和瓜蚜室内杀虫活性及田间防治效果

通过室内毒力测定及田间药效试验评价氟啶虫胺腈原药以及22%氟啶虫胺腈悬浮剂和50%氟啶虫胺腈水分散粒剂对桃蚜和瓜蚜的杀虫活性。分别采用浸叶法和常规喷雾法进行室内毒力测定和田间药效试验。室内毒力测定结果表明,氟啶虫胺腈原药对桃蚜和瓜蚜48 h LC50值分别为0.98 mg/L和1.70 mg/L,氟啶虫胺腈对桃蚜和瓜蚜的相对毒力分别是啶虫脒的4.2倍和2.0倍。田间药效试验结果表明,22%氟啶虫胺腈悬浮剂和50%氟啶虫胺腈水分散粒剂对桃蚜和瓜蚜具有很好的速效性和持效性,平均防治效果为82.0%~96.0%。氟啶虫胺腈可有效防治桃蚜和瓜蚜,是农业生产上防治蚜虫的理想药剂之一。     

Xenorhabdus poinarii 5-5B杀虫毒素的分离纯化与活性测定

首次从全国采集的土样,分离并筛选出高毒力共生菌菌株Xenorhabdus poinarii 5-5B,首次对Xenorhabdus poinarii的杀虫毒素进行分离纯化,通过硫酸铵沉淀法对其杀虫毒素进行分离后,再利用DEAE-52层析柱进行了纯化,共得到7个峰,各峰的回收产物进行活性测定(干粉以5μg/L溶于去离子水)结果表明,各峰产物对亚洲玉米螟、黄粉虫、小菜蛾、黏虫和甜菜夜蛾均具有较高的胃毒活性.     

一株白僵菌的分离鉴定及对黄胸散白蚁的室内毒力测定

从罹病的玉米螟(Ostrinia furnacalis G)中分离纯化获得一株新菌株,命名为Bb-1。通过对该菌株的培养性状、形态特征观察,以及ITS基因序列分析,鉴定出Bb-1菌株为白僵菌属的球孢白僵菌(Beauveria bassiana)。用该菌株的5种浓度孢子液对黄胸散白蚁进行毒力试验。结果表明:用浓度为5×10~7孢子/mL的孢子液处理8d,黄胸散白蚁的校正死亡率达95.00%。5~8d的LC_(50)值为2.05×10~4~9.05×10~6孢子/mL。在5×10~3~5×10~7孢子/mL浓度下,菌株的LT_(50)值为4.28~8.59d。     

The Role of the Glutathione System in Stress Adaptation,Morphogenesis and Virulence of Pathogenic Fungi

Morphogenesis and stress adaptation are key attributes that allow fungal pathogens to thrive and infect human hosts. During infection, many fungal pathogens undergo morphological changes, and this ability is highly linked to virulence. Furthermore, pathogenic fungi have developed multiple antioxidant defenses to cope with the host-derived oxidative stress produced by phagocytes. Glutathione is a major antioxidant that can prevent cellular damage caused by various oxidative stressors. While the role of glutathione in stress detoxification is known, studies of the glutathione system in fungal morphological switching and virulence are lacking. This review explores the role of glutathione metabolism in fungal adaptation to stress, morphogenesis, and virulence. Our comprehensive analysis of the fungal glutathione metabolism reveals that the role of glutathione extends beyond stressful conditions. Collectively, glutathione and glutathione-related proteins are necessary for vitality, cellular development and pathogenesis.     

桃蚜的饲养及其在杀虫剂生测筛选中的应用

介绍了一种新的生测筛选靶标桃蚜的室内饲养方法及几种不同的生测方法.     

Genetic Diversity Analysis Reveals Potential of the Green Peach Aphid (Myzus persicae) Resistance in Ethiopian Mustard

Brassica carinata (BBCC, 2n = 34) is commonly known as Ethiopian mustard, Abyssinian mustard, or carinata. Its excellent agronomic traits, including resistance to biotic and abiotic stresses, make it a potential genetic donor for interspecific hybridization. Myzus persicae (green peach aphid, GPA) is one of the most harmful pests of Brassica crops, significantly effecting the yield and quality. However, few aphid-resistant Brassica crop germplasms have been utilized in breeding practices, while the underlying biochemical basis of aphid resistance still remains poorly understood. In this study, we examined the genetic diversity of 75 B. carinata accessions and some plant characteristics that potentially contribute to GPA resistance. Initially, the morphological characterization showed abundant diversity in the phenotypic traits, with the dendrogram indicating that the genetic variation of the 75 accessions ranged from 0.66 to 0.98. A population structure analysis revealed that these accessions could be grouped into two main subpopulations and one admixed group, with the majority of accessions (86.67%) clustering in one subpopulation. Subsequently, there were three GPA-resistant B. carinata accessions, BC13, BC47, and BC51. The electrical penetration graph (EPG) assay detected resistance factors in the leaf mesophyll tissue and xylem. The result demonstrated that the Ethiopian mustard accessions were susceptible when the phloem probing time, the first probe time, and the G-wave time were 20.51–32.51 min, 26.36–55.54 s, and 36.18–47.84 min, respectively. In contrast, resistance of the Ethiopian mustard accessions was observed with the phloem probing time, the first probe time, and G-wave time of 41.18–70.78 min, 181.07–365.85 s, and 18.03–26.37 min, respectively. In addition, the epidermal characters, leaf anatomical structure, glucosinolate composition, defense-related enzyme activities, and callose deposition were compared between the resistant and susceptible accessions. GPA-resistant accessions had denser longitudinal leaf structure, higher wax content on the leaf surface, higher indole glucosinolate level, increased polyphenol oxidase (PPO) activity, and faster callose deposition than the susceptible accessions. This study validates that inherent physical and chemical barriers are evidently crucial factors in the resistance against GPA infestation. This study not only provide new insights into the biochemical basis of GPA resistance but also highlights the GPA-resistant B. carinata germplasm resources for the future accurate genetic improvement of Brassica crops.     

哒嗪类衍生物杀虫杀螨活性研究进展

哒嗪类化合物在新农药的创制中占有重要地位.近年来,以哒嗪杂环为母体进行新型杀虫杀螨剂的创制引起了广泛关注,并发现了许多具有良好杀虫杀螨活性的哒嗪衍生物.按哒嗪衍生物的结构特征进行分类,对哒嗪衍生物在杀虫杀螨活性方面的应用进行了介绍,并对它的发展前景作了进一步展望.