长江流域稻区二化螟抗药性监测

2008-2009年期间,采用毛细管点滴法测定了浙、苏、皖、湘、鄂、川、豫等7省17个种群二化螟4龄幼虫对常用杀虫剂的抗性,结果表明:长江流域稻区二化螟对杀虫剂的抗性分布存在明显的区域性。高抗区浙江南部的苍南、瑞安、江山二化螟种群对20世纪70-90年代广泛使用的沙蚕毒素类的杀虫单(抗性倍数43.2～177.0倍)和有机磷类的三唑磷(238.7～728.1倍)、毒死蜱(31.7～57.8倍)均产生了高-极高水平抗性,且对近年来开始广泛使用的氟虫腈(11.2～24.7倍)和阿维菌素(5.9～7.1倍)也产生了中等或低水平抗性;中抗区的安徽庐江、湖南攸县、江苏高淳种群对三唑磷产生极高水平抗性(203.2～379.0倍),对杀虫单(18.3～48.8倍)和毒死蜱(29.8倍)产生了中等-高水平抗性,对氟虫腈(4.4倍)和阿维菌素(4.1～4.7倍)为敏感性降低;低抗区除江苏仪征种群对毒死蜱(45.2倍)、安徽和县种群对三唑磷(50.0倍)开始产生高水平抗性外,对其他杀虫剂为敏感-中等水平抗性,对氟虫腈和阿维菌素为敏感;敏感区的河南信阳、江苏连云港、四川武胜种群除对个别杀虫剂(如杀虫单)为低水平抗性外,对其他大多数杀虫剂为敏感-敏感性降低。还讨论了按抗性分布的区域性来制定相应的抗性治理方案。     

二化螟抗药性监测和对三唑磷抗性的遗传分析

采用点滴法测定了2001~2002年浙、苏、皖、赣等4省水稻二化螟4龄幼虫对氟虫腈、阿维菌素、三唑磷及杀虫单等的抗性;用三唑磷高抗种群经室内筛选纯化后与室内敏感种群进行正反交、回交,对三唑磷抗性进行了初步遗传分析。结果表明：(1) 通过对4省7个种群的检测,发现浙江瑞安种群对氟虫腈有低水平抗性（抗性倍数为6.5倍）,其他种群虽存在敏感度差异（1.0~1.6倍）,但均属敏感范围;(2) 浙、苏、皖三省6个不同种群对阿维菌素的敏感度变化小于2.3倍,未检测到明显抗药性;(3) 4省10个种群对三唑磷敏感度变化很大（LD50值为有效成分0.0052~1.0114 μg/头）,其中瑞安种群具有高水平抗性（163.1倍）,温州种群为中等水平抗性（18.2倍）,常熟、锡山和金坛3种群为低水平抗性（6.7~9.7倍）,新洋农场、楚州、连云港、宜丰和太湖5种群为敏感（0.8~2.9倍）;(4) 4省9个种群对杀虫单均有不同程度抗药性,瑞安和宜丰种群达高水平抗性（113.7和57.6倍）,温州、常熟、金坛和太湖4种群为中等水平抗性（11.0~29.7倍）,新洋农场和锡山种群为低水平抗性（6.7和7.5倍）,灌云种群抗性最低,为3.7倍;(5)瑞安种群对三唑磷抗性属单个主基因控制的不完全显性性状,但不排除微效修饰基因的存在。     

水稻挥发物对二化螟幼虫趋性行为的影响

 利用Y型嗅觉仪研究了水稻挥发物对二化螟初孵幼虫和3龄幼虫的趋性影响。处理包括健康苗与空白对照、二化螟为害苗与空白对照、稻纵卷叶螟为害苗与空白对照、健康苗与二化螟为害苗、健康苗与稻纵卷叶螟为害苗、二化螟为害苗与稻纵卷叶螟为害苗。结果表明，水稻挥发物对二化螟初孵和3龄幼虫都表现出显著的引诱作用。二化螟幼虫对不同处理水稻（健康苗、二化螟为害苗和稻纵卷叶螟为害苗）挥发物之间的趋向选择无显著差异。     

二化螟对杀虫单抗性现实遗传力与遗传方式

 以2001年田间采集的温州二化螟为起始种群，在室内饲养24代期间，用点滴法处理4龄幼虫进行杀虫单筛选19代，得到抗性品系WZ R；与敏感基线相比， WZ R品系对杀虫单抗性达774.5倍，比筛选前上升25.0倍；根据前期连续6代（F3~F8）筛选估计的抗性现实遗传力（h2，0.230）显著低于根据后期连续5代（F19~F23）筛选的h2（1205），而中间不连续筛选（F9~F18，10代中有4代未筛选）的h2最小（0.024）。用毒力回归线法对WZ R品系进行抗性遗传分析表明，杀虫单抗性为不完全显性（正反交显性度分别为0.56和0.63）、常染色体遗传，抗性不属于单个主基因控制。     

二化螟对氟虫腈抗性初探

 采用点滴测定法，于2001~2004年对江、浙、皖3省12个县市的二化螟进行了氟虫腈的抗性调查。江苏及安徽等地二化螟对氟虫腈仍处于敏感状态，但江苏无锡和浙江慈溪二化螟的敏感性明显下降（抗性倍数RR分别为3.1和3.6倍），浙江苍南二化螟已出现中等水平的抗性（RR为21.2倍）。由此认为，二化螟目前仍处于对氟虫腈抗性发展的早期阶段。解毒酶抑制剂的活体增效实验发现，TPP、DEM能明显提高氟虫腈对抗性二化螟的毒力（增效比SR分别为1.8和1.6），但PBO在敏感性和抗性二化螟中的增效作用均不显著（SR为1.1~1.2）。表明酯酶和谷胱甘肽转移酶与二化螟对氟虫腈抗性的形成有一定关系。不同杀虫剂的比较毒力测定表明，三唑磷和敌百虫由于产生了抗性，对二化螟的毒力很低，乙酰甲胺磷本身对二化螟的毒力也不高，已很难再用来防治抗性二化螟。但哒嗪硫磷、二嗪磷、溴氰菊酯和阿维菌素对二化螟的毒力较高，而且尚没有明显的抗性产生，在二化螟抗性治理中，可以用作氟虫腈的轮换防治药剂。     

水稻病虫防控节药增效技术适用性研究

2014年采用大区试验示范,研究了水稻病虫防控节药增效技术在江华瑶族自治县（南方水稻黑条矮缩病重发区）及醴陵市（机插秧稻区）的适用性。结果表明,在南方水稻黑条矮缩病及机插秧稻区,水稻病虫防控节药增效技术能有效控制南方水稻黑条矮缩病、纹枯病、稻纵卷叶螟、二化螟及稻飞虱的危害,对其防效分别达95.70%~100.00%、60.36%~84.84%、80.73%~90.41%、95.77%和74.31%~82.06%。此外,该技术的用药量比常规施药技术减少55.62%~78.25%,种稻效益增加209.73~289.35元/667 m2。     

直播稻区稻水象甲种群动态及分布

对浙江省象山县山谷小平原直播稻区的稻水象甲种群动态和田间分布进行了系统调查。稻水象甲成虫在山坡地和直播稻田埂等越冬场所出蛰后取食杂草,并于5月初同期出现成虫高峰。这些成虫约7 d后直接迁入直播稻田,形成直播稻田稻水象甲的迁入高峰。稻水象甲在直播稻田的取食、产卵和分布表现出明显的喜水习性。在同一丘直播稻田内,离田边越近,越冬代成虫和一代卵、幼虫、茧蛹的数量越大;在同一畦内,畦边多于畦中。稻水象甲在直播稻田完成一个世代约需50 d,增殖倍数（一代成虫峰值/越冬代成虫峰值）为7.23,明显低于移栽稻田,主要原因是稻水象甲在直播稻上的产卵量较低。7月底一代成虫向山坡地和直播稻田埂等越夏越冬场所回迁。根据直播稻区稻水象甲种群动态和分布特点,提出了相应的虫情调查和测报防治建议。     

山东稻区二化螟对6种药剂的敏感度研究

为明确山东省不同稻区二化螟对不同类型杀虫剂的敏感性水平,筛选出绿色、高效的杀虫剂,采用人工饲料药膜法测定了山东省代表性稻区二化螟对6种杀虫剂的敏感度。结果表明,东营、济南、济宁、临沂稻区的二化螟对甲维盐、印楝素的敏感度最高,对阿维菌素、氯虫苯甲酰胺、苏云金杆菌的敏感度较高,对毒死蜱的敏感度较低。临沂稻区二化螟对氯虫苯甲酰胺的敏感性指数是东营稻区的1.58倍,济宁稻区二化螟对毒死蜱的敏感性指数是东营稻区的1.56倍;四个稻区二化螟种群对其它4种药剂的敏感度差别不大。     

二化螟对双酰胺类杀虫剂的抗药性监测和交互抗性研究

【目的】为了及时了解我国主要稻区二化螟对氯虫苯甲酰胺和氟苯虫酰胺的抗药性发展情况,同时明确对氯虫苯甲酰胺原药和制剂的抗性水平是否存在差异及二化螟对新研发的双酰胺类杀虫剂溴氰虫酰胺、四氯虫酰胺及氯氟氰虫酰胺与氯虫苯甲酰胺、氟苯虫酰胺间是否存在交互抗性。【方法】采用稻苗浸渍法测定了2015年我国7省19地二化螟田间种群对氯虫苯甲酰胺和氟苯虫酰胺的抗药性,同时测定了浙江余姚和象山两个抗性种群对97.3%氯虫苯甲酰胺原药、20%氯虫苯甲酰胺悬浮剂制剂的抗药性及其对溴氰虫酰胺、四氯虫酰胺及氯氟氰虫酰胺与氯虫苯甲酰胺和氟苯虫酰胺间的交互抗性。【结果】浙江余姚和苍南种群对氯虫苯甲酰胺已达141.1倍和135.0倍的高水平抗性,象山种群为87.9倍的中等水平抗性;这三个种群对氟苯虫酰胺均表现为中等水平抗性(15.0~58.7倍)。二化螟对97.3%氯虫苯甲酰胺原药和20%氯虫苯甲酰胺悬浮剂制剂存在抗性差异,浙江余姚和象山种群对制剂的抗性更高。交互抗性研究结果显示,对氟苯虫酰胺和氯虫苯甲酰胺均产生了中到高水平抗性(27.6~133.6倍)的象山、余姚种群,对溴氰虫酰胺、四氯虫酰胺和氯氟氰虫酰胺同样也产生了中到高水平抗性(30.3~127.0倍)。【结论】各二化螟地理种群之间对氯虫苯甲酰胺和氟苯虫酰胺抗药性差异较大,分别表现出117.6倍和146.8倍的差异,浙江余姚和象山二化螟种群对20%氯虫苯甲酰胺悬浮剂制剂抗药性更高且三种新双酰胺类杀虫剂与氯虫苯甲酰胺和氟苯虫酰胺之间存在交互抗性。     

盘锦稻区二化螟发生情况及对水稻减产的调查

为准确掌握盘锦稻区常发性水稻害虫二化螟发生情况,做好害虫预测预报,为害虫防治工作提供依据,通过对盘锦新建基地、胡家镇、西安农场和王家农场4个稻区的二化螟越冬代、一代与二代害虫发生情况进行调查,使用黑光灯诱蛾技术,结果表明,盘锦稻区越冬代二化螟存活率约为20%左右,一代蛾羽化高峰期为6月24~26日,卵始盛期稍晚1~2d,二代蛾羽化高峰在7月底至8月初,世代略不整齐,落卵高峰期与成虫羽化在同一时期。调查也显示,二化螟能明显地降低水稻产量,生产中必须重视对二化螟的防治。     

防治水稻二化螟的高毒农药替代药剂的室内筛选

为了筛选防治水稻二化螟的高毒农药替代药剂,采用点滴法测定了7类32种药剂对不同水稻生态区二化螟种群的室内毒力。基于这些毒力数据,推荐对二化螟毒力较高的7种新型农药（氟虫腈、阿维菌素、甲氨基阿维菌素苯甲酸盐、虫酰肼、呋喃虫酰肼、氟铃脲和氟啶脲）和一些中低毒性的有机磷品种（如辛硫磷、喹硫磷、毒死蜱和哒嗪硫磷）作为大田药效试验的候选替代药剂。评估了田间二化螟对10种拟除虫菊酯类杀虫剂的敏感性,发现7种对鱼高毒的拟除虫菊酯类杀虫剂（高效氟氯氰菊酯、λ 高效氯氟氰菊酯、溴氰菊酯、高效氯氰菊酯、顺式氯氰菊酯、甲氰菊酯和S 氰戊菊酯）对二化螟的毒力高于大多数有机磷类农药。虽然我国禁止上述菊酯类杀虫剂在水稻上使用,但是浙江瑞安田间种群（RA05）已对高效氟氯氰菊酯、溴氰菊酯、高效氯氰菊酯和λ 高效氯氟氰菊酯等产生高水平抗性（抗性倍数分别为166.7、51.9、41.3和36.8倍）。对鱼低毒的3种菊酯类农药（乙氰菊酯、醚菊酯和氟硅菊酯）对抗性二化螟（RA05）的毒力高于三唑磷。因此,可考虑将这些对鱼低毒的菊酯类农药作为防治水稻二化螟的高毒农药的替代药剂和抗性治理的轮换品种。     

江浙麦区灰飞虱春季种群的发生消长和迁飞动态

 对灰飞虱进行越冬调查、田间调查、卵巢解剖、逐时扑灯行为观察、迁飞轨迹和虫源地分析发现：1）灰飞虱以3~5龄若虫越冬,并以4龄为主;2）江苏北部麦田灰飞虱若虫于3月越冬结束,3-4月陆续发育羽化为越冬代成虫,4-5月在麦田繁殖为第1代若虫;3）浙江海宁春季第1代灯诱灰飞虱具有本地迁出和外地迁入两种性质与时期,并可依卵巢发育级别加以区分;4）春夏季浙江海宁灰飞虱可由本地越冬虫源繁衍而来,或由江苏、安徽、浙江、江西、福建等省迁入。无论从越冬寄主小麦向夏寄主水稻扩散转移,或6月初大量外地迁入,杂草充当了极其重要的中间寄主;5）逐时灯诱观察结果表明,迁出期灰飞虱起飞呈晨暮双峰型,迁入期在19:00至次日凌晨5:00,每1 h均有上灯,以上半夜居多; 6）利用美国NOAA的HYSPLIT轨迹模拟平台对主要迁入期进行数值模拟和虫源地分析,结果表明,2009年5月底至6月初迁入浙江海宁的灰飞虱虫源地来自江苏北部和中部、皖南、浙南、赣东北和闽西北等地区。     

Preliminary Study on Resistance of the Rice Stem Borer （Chilo Suppressalis） to Fipronil

By means of topical application, fipronil resistance was surveyed in the rice stem borer, Chilo suppressalis, from 12 diferent areas in east China from 2001 to 2004. The rice stem borers in most regions of Jiangsu and Anhui were still susceptible to fipronil. But in Wuxi, Jiangsu Province and Cixi, Zhejiang Province, their sensitivity became decreased （resistance ratios were 3.1 and 3.6, respectively）, and the medium level of resistance （resistance ratio was 21.2） was found in Cangnan, Zhejiang Province. So, it was still at the early stage for fipronil resistance development in this pest. Synergism experiments showed that piperonyl butoxide（PBO） had a little effect on both susceptible and resistant borers （synergism ratios were 1.1-1.2）. Though triphenyl phosphate （TPP） and diethyl meleate （DEM） had no effect on the susceptible borers, they had significant synergism on fipronil in the resistant population to fipronil （synergism ratios were 1.8 and 1.6, respectively）, indicating esterase and glutathion S-transferase may be involved in the resistance mechanism. Bioassay with currently used insecticides indicated that triazophos （because of high resistance）, trichlorphon and acephate had very low toxicity to resistant borers. But diazinon, pyridaphenthion, decamethrin and avermeatin showed high toxicity and had no cross resistance to fipronil, which could be considered as substitute insecticides in the resistance managment.     

Suppression of Rice Stem Borer, Chilo suppressalis by Mass Trapping Using Synthetic Sex Pheromone in Paddy Field

Suppressing effects of mass trapping using synthetic sex pheromone with main active ingredients of Z-11-hexadecenal, Z-13-octadecenal and Z-9-hexadecenal on the rice stem borer, Chilo suppressalis were investigated during the flight periods of the overwintering and 1st generation in the paddy area of 60 ha in 1999. Population density of C. suppressalis in the pheromone-treated fields was lower than that in control. The egg masses decreased by 74.39% and population size of adult males of the 1st generation decreased by 61.64% in the treated fields as compared to control. Meanwhile, the damage by C.suppressalis larvae was significantly lower in the treated fields than control (t-test, P=0.05). Percentages of brownish leaf sheath, dead heart, and white head in the treated fields were decreased by 70.90%, 57.01% and 44.30%, respectively in contrast to control. The present study demonstrated that mass trapping to C. suppressalis using synthetic sex pheromone shows great potential as an alternative measure in an environment-friendly pest management and at the same challenging the insecticide use that has some environment impacts.     

Suppression of Rice Stem Borer, Chilo suppressalis by Mass Trapping Using Synthetic Sex Pheromone in Paddy Field

Suppressing effects of mass trapping using synthetic sex pheromone with main active ingredients of Z-11-hexadece-nal, Z-13-octadecenal and Z-9-hexadecenal on the rice stem borer, Chilo suppressalis were investigated during the flight periods of the overwintering and 1^st generation in the paddy area of 60 ha in 1999. Population density of C. suppressalis in the pheromone-treated fields was lower than that in control. The egg masses decreased by 74. 39% and population size of adult males of the 1^st generation decreased by 61.64% in the treated fields as compared to control. Meanwhile, the damage by C.suppressalis larvae was significantly lower in the treated fields than control (t-test, P=0.05). Percentages of brownish leaf sheath, dead heart, and white head in the treated fields were decreased by 70.90%, 57.01% and 44.30%, respectively in contrast to control. The present study demonstrated that mass trapping to C. suppressalis using synthetic sex pheromone shows great potential as an alternative measure in an environment-friendly pest management and at the same challenging the insecticide use that has some environment impacts.     

水稻穗期大螟药剂防治技术探讨

为有效控制水稻穗期大螟的危害,笔者针对性地开展了不同药剂、喷液量和用药时间等田间试验示范。结果表明,氯虫苯甲酰胺、稻丰散、阿维·二嗪磷、阿维·三唑磷、阿维·杀螟松、乐果·三唑磷和唑磷·敌百虫等对大螟均具有理想的防治效果,可作为水稻穗期大螟的防治药剂。其中,氯虫苯甲酰胺和稻丰散不仅在大螟卵孵期使用效果好,而且对低龄幼虫的杀灭效果也较明显。在常规喷雾施药时,每hm2的喷液量以1 000 kg较为适宜。大螟偏重发生时,宜在卵孵始盛与高峰期连续用药2次,必要时,在低龄幼虫高峰期或田间危害始见期,再复查补充用药1次。     

Diversity of Midgut Microbial Community of Chilo suppressalis Exposed to Chlorobenzamide

【Objective】We aim to illuminate the structural changes in the midgut microbial community of Chilo suppressalis exposed to chlorobenzamide.【Method】Macrogenomic sequencing and in vitro culture were used to analyze the diversity of midgut microbiota of Chilo suppressalis treated with different concentrations (100, 200, 400 µg/mL) of chlorobenzamide .【Result】The results showed that chlorobenzamide treatment decreased the abundance and diversity of the midgut bacteria of Chilo suppressalis,and the OTU number and specific OTU number of the intestinal bacteria of treated population were lower than those of the control; the proportion of Morganella, Provincia and Proteus in the chlorobenzamide treated population increased significantly. Meanwhile, the result of in vitro culture indicated besides enterobacter, Lelliotti nimipressuralis, Leclercia decarboxylata, Pantoea agglomerans were isolated from chlorobenzamide treated Chilo suppressalis population. COG classification and KEGG analysis didn’t show significant difference in number and relative abundance of functional genes among control and three chlorobenzamide treated populations.【Conclusion】The study had clarified the diversity of intestinal bacteria and the relationship between gut bacteria of Chilo suppressalis and the formation of chlorobenzamide resistance, and will lay a scientific basis for the role of intestinal bacteria in resistance of Chilo suppressalis to chlorobenzamide.