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1.
张润杰  林宪德 《昆虫知识》1992,29(5):263-265
本文通过分析三化螟历年各世代的始见日、高峰日的出现日期及其相关关系,建立了以线性回归模型为基础的、以始见日和高峰日为参照点的三化螟发生期预测模型,结合卵的发育历期和有效积温,预测该虫孵化高峰的日期。同时以冬至后出现5mm(或5mm)的降雨量作为积温参照点,预测三化螟第一代成虫始见日期。  相似文献   

2.
梧桐木虱生物学及其防治   总被引:2,自引:0,他引:2  
梧桐木虱ThysanogynaLimbtaEnddeyein又名青桐木虱,为单食性害虫,仅为害梧桐(青桐入近年来,此虫为害日趋严重,造成幼树落叶,花枝枯死,花蕾脱落。若虫分泌蜡丝,墙塞叶面气孔,同时污染环境,并招致寄生烟煤病。!生活史该由每年发生2代,少数可发生3代,以卵在枝端、鳞芽的苞叶上、幼树树干或疤痕及糙皮中越冬。越冬卵4月下旬至5月上旬孵化,低温年份可延至5月中下旬。5月下旬至6月上中旬是若虫为害高峰期。第一代成虫发生较为整齐,6月上旬始见,高峰为6月下旬至7月上旬。此期间,被害花蕾脱落达65%以上,花枝枯死,叶面烟煤病大…  相似文献   

3.
调查表明,厦门菩提皮粉虱若虫发生高峰期分别在8月上旬(8月1日)、8月下旬(8月29日)、9月下旬(9月28日)和11月中旬(11月12日),卵的高峰期出现在7月下旬(7月26日)、8月下旬(8月29日)、9月下旬(9月28日)和10月下旬(10月31日)。在厦门一年可发生5代,其中第四代虫口数量达到全年高峰,菩提皮粉虱12月中旬开始越冬。  相似文献   

4.
樟个木虱形态特征及生物学特性   总被引:3,自引:0,他引:3  
樟个木虱Triozacamphorae是近年来上海地区香樟上发生的一种新害虫。作者对其形态和生物学特性进行了研究。樟个木虱在上海以 1年发生 2代为主 ,偶发 3代。樟个木虱以低龄若虫在叶片上越冬 ,3月下旬至 4月上旬越冬代羽化 ;第 1代开始于 3月下旬 ,羽化高峰在 6月份 ;第 2代开始于 5月下旬 ,并主要以该代若虫越冬 ;第 3代若虫偶发 ,开始于 7月上旬 ,以若虫越冬。樟个木虱第 1代若虫的平均发育历期为 5 0 72d,1~ 5龄若虫的历期分别为 :1 8 .3 1± 2 .2 1d ,1 4. 90± 9. 92d,6 .1 1± 2 . 2 0d,5 .80±3 . 61d ,5 60± 1 5 1d。成虫的寿命为 3~ 1 1d ,平均寿命为 6 41d。樟个木虱的产卵量为 3 9. 1粒 雌虫。2 4℃下 ,卵历期 5~ 7d不等 ,平均为 5. 3 4± 0 . 5 7d ,卵平均孵化率为 83 . 7%。樟个木虱低龄若虫中 3龄若虫最耐高温 ,其次为 2龄若虫 ,1龄若虫最不耐高温。  相似文献   

5.
二化螟在豫南每年主要发生两代,个别发生一代或三代。通过饲养和测螟灯观察:越冬代蛾一般始见于4月下旬或5月初,盛发于5月中、下旬至6月初,终见期为6月中、下旬;第一代蛾一般始见于7月上旬,盛发于7月中、下旬,终见于8月上、中旬;第二代蛾一般始见于8月中、下旬,盛见于8月下旬,终见于8月底或9月中旬。今将各虫态历期和出现期分别制为表1和表2。  相似文献   

6.
紫薇绒蚧的生物学特性与药剂防效   总被引:4,自引:0,他引:4  
紫薇绒蚧Eriococcus lagerostroemiae Kuwana是皖北地区严重危害紫薇(Lagerstroemia indiceL.)的虫害之一。该虫年发生2代,以第2代2龄若虫和蛹在寄主枝条缝隙内越冬。翌年4月下旬,成虫出现、羽化、交配、产卵。周年虫口变动出现2个高峰(中/6~下/6和下/8~上/9);相对其它参照药剂,2.5%高效氯氰菊酯的毒力最佳、其防效与其它3种药剂防效差异显著,对紫薇绒蚧致死中量(LC50)为4.9818mg/L,有效成分为16.7mg/L时的校正防效为94.52%。据此,在6月上旬和8月中旬若虫孵化盛期,施用有效成分为16.7mg/L的2.5%高效氯氰菊酯乳油能得到良好的防治效果。  相似文献   

7.
黄杨绒蚧Eriococcus abeliceae Kuwana是危害园林树木的重要害虫之一。该蚧在西宁地区1年发生1代,以2龄若虫在树干裂皮缝中越冬。翌年3月下旬2龄若虫蜕皮变为3龄若虫,开始为害,雌虫5月上旬开始产卵,卵期18~23d,每雌虫产卵量134~424粒,平均287粒。6月上旬卵开始孵化,孵化率100%。雌虫3龄,雄虫2龄。在室内自然变温条件下,对黄杨绒蚧卵的发育起点温度和有效积温进行测定。结果表明:卵发育起点温度12.98℃,有效积温39.03日.度;预测式为N=(39.03±2.66)/T-(12.98±0.18)。  相似文献   

8.
白翅叶蝉(Thaia subrufa Motschulsky)在浙江省东阳县,一年大部发生二代。第一、二代成虫分别于6月下旬至7月上、中旬和8月下旬至9月中旬盛发于早稻和双季晚稻,第二代成虫大部分越冬,少数早发的才能发生第三代。第一、二和三代卵历期分别为17—19、11—12和15一19天,若虫历期分别为19、16和24天。成虫4℃开始活动,10℃开始取食,15℃开始羽化和产卵。卵开始发育温度在20℃左右。成虫无孤雌生殖现象,产卵前期在第一、二代分别为23和17天,越冬成虫则长达6—8月之久。每雌产卵量以越冬代最高,以后各代急剧下降。越冬后成虫在4月下旬几乎全部集中于早、中稻秧田,产卵盛期在5月即早稻本田分蘗期。繁殖寄主仅限于水稻。 因白翅叶蝉具有这些生物学特性,所以防治适期为早季秧田。1964—1965年在东阳县早季秧田大面积防治结果,可减低早、中稻本田虫口90%以上,且能压低双季晚稻田的虫口密度。  相似文献   

9.
2009—2011年对内蒙古呼和浩特市郊区十字花科蔬菜和武川县油菜上小菜蛾Plutella xylostella(L.)种群消长动态进行了调查,并比较了呼和浩特地区小菜蛾对11种杀虫剂的抗药性。结果表明,在呼和浩特郊区,小菜蛾成虫于4月上旬开始出现,一年中有4个发生高峰,分别为4月下旬或5月上旬、6月中旬、8月下旬和10月上旬;小菜蛾幼虫在春甘蓝和秋白菜整个生长期间均有发生,大约有4个发生高峰,分别为6月上中旬、6月下旬或7月上旬、9月上旬和10月上旬。在武川县,小菜蛾成虫于4月末或5月初开始发生,春夏季数量高于秋季,共有2个发生高峰,2009年为5月下旬和6月中旬,2010年为6月上旬和8月上中旬;小菜蛾幼虫在6月下旬开始出现,在油菜整个生长期间,小菜蛾幼虫约有3个数量高峰,分别为7月初、7月末和8月下旬,秋季数量高于春夏季。在供试的11种杀虫剂中,溴虫腈对小菜蛾幼虫的毒力最高,LC50为0.22 mg·L-1;其次为多杀菌素、氯虫苯甲酰胺、氟虫腈和BT,LC50分别为0.820.83、1.09、1.36和3.41 mg·L-1;再次为茚虫威和阿维菌素,LC50分别为15.74 mg·L-1和6.030.83、1.09、1.36和3.41 mg·L-1;再次为茚虫威和阿维菌素,LC50分别为15.74 mg·L-1和6.0323.47 mg·L-1;然后为丁醚尿、虫酰肼和啶虫隆,LC50分别为51.30、52.66和61.91 mg·L-1;最低为高效氯氰菊酯,LC50为462.6623.47 mg·L-1;然后为丁醚尿、虫酰肼和啶虫隆,LC50分别为51.30、52.66和61.91 mg·L-1;最低为高效氯氰菊酯,LC50为462.66673.26 mg·L-1。抗药性测定表明,呼和浩特地区小菜蛾幼虫未对溴虫腈、虫酰肼、氯虫苯甲酰胺和丁醚尿产生抗性,对多杀菌素和氟虫腈为低抗性,对茚虫威和BT为中抗性,对高效氯氰菊酯、啶虫隆和阿维菌素为极高抗性。  相似文献   

10.
【目的】葡萄穴粉虱是近年来入侵新疆吐鲁番地区的一种新害虫,明确其在新疆吐鲁番地区的生物学特性及发生危害情况,可为防治策略的制定提供科学依据。【方法】通过室内观察和田间调查,了解葡萄穴粉虱的形态学特征及生物学特性。【结果】葡萄穴粉虱属过渐变态。成虫复眼红棕色,翅膀表面覆盖白色蜡粉。卵倒锥形。若虫共4龄,扁椭圆形,体缘有蜡丝,末龄若虫在体壳内化蛹。4龄若虫(拟蛹)有半透明和黑色2型,越冬型4龄若虫(拟蛹)为黑色且有金属光泽。该虫在吐鲁番1年发生3~4代。越冬代成虫于4月上中旬破蛹羽化,开始在葡萄园危害,5月中旬第1代若虫孵化,5月下旬为孵化高峰;6月中旬2代若虫开始孵化,6月下旬—7月初为孵化高峰,世代重叠严重,10月中下旬之后以越冬代蛹在枯叶和枯枝上越冬。除为害葡萄外,葡萄穴粉虱还危害五叶地锦等葡萄科植物。【结论】在葡萄冬季埋土前或春季上架时,清除枯枝落叶可以大量减少越冬虫源,减轻防治压力。5月中旬第一代若虫孵化高峰期是化学防治的关键时期。在重点开展葡萄园防治的同时,应加强对五叶地锦等园林植物的防治。  相似文献   

11.
The diamondback moth Plutella xylostella (L.) has a great economic importance in Brassicaceae crops in many parts of the world. Recurrent infestations of this pest in growing areas of Pernambuco state, Brazil, have led farmers to frequently spray their crops with insecticides. However, control failures by several insecticides have been alleged by farmers. The objective of this study was to check whether resistance to insecticides could explain these control failures in P. xylostella. Populations of P. xylostella from Pernambuco were collected between January and April 2009. The resistance ratios of P. xylostella populations were compared among five different active ingredients: abamectin, methomyl, lufenuron, indoxacarb, and diafenthiuron by leaf dipping bioassays using foliar discs of kale leaves. Mortality data were submitted to probit analysis. The P. xylostella populations showed variable response and significant resistance to one or more insecticides. The population from Bezerros County exhibited the highest resistance ratios to indoxacarb (25.3 times), abamectin (61.7 times), and lufenuron (705.2 times), when compared to the reference population. The populations from Bonito and Jupi Counties were 33.0 and 12.0 times more resistant to lufenuron and abamectin, respectively, when compared with the reference population. Resistance to methomyl was the least common, but not less important, in at least four populations. These results indicated that control failures were associated with resistance by some of the evaluated insecticides, reinforcing the need for resistance management in areas of the state of Pernambuco.  相似文献   

12.
小菜蛾颗粒体病毒对小菜蛾防治作用的评价   总被引:6,自引:1,他引:5  
莫美华  庞雄飞 《生态学报》1999,19(5):724-727
用以作用因子组配的生命表,种群趋势指数和控制指数评价小菜蛾颗粒体病毒对小菜蛾种群动态的作用。结果表明,施用该病毒对小菜蛾种群动态有明显的控制作用,种群趋势指数为0.97,干扰作用控制指数为0.19,即施用病毒后,其种群趋势指数相当于对照的0.19,施用化学杀虫剂的种群趋势指数为7.20,干扰作用控制指数为1.43,即种群趋势指数将增长为对照的1.43倍。  相似文献   

13.
非嗜食植物乙醇提取物对小菜蛾种群的控制作用研究   总被引:8,自引:2,他引:6  
应用作用因子生命表方法以及在此基础上提出的干扰作用控制指数法评价了几种非嗜食植物乙醇提取物对小菜蛾(Plutella xylostella)种群的控制作用.结果表明,非寄主植物的乙醇提取物(浓度为0.01 g·ml-1)即飞机草(Eupatorium odoratum)、马缨丹(Lantana camara)和蟛蜞菊(Wedelia chinensis)对保护菜心免受小菜蛾为害起着明显的作用,这些作用物质在处理区的干扰作用控制指数分别为0.110、0.136和0.165,对小菜蛾的防治效果可达89.0%、86.4%和83.5%.可见,3种供试作用物质对小菜蛾种群起着重要的控制作用.  相似文献   

14.
掌握滇西菜区小菜蛾Plutella xylostella种群发生规律和抗药性水平,对提出区域性防控策略具有重要意义。2009-2015年,采用诱集法和浸叶法监测了滇西菜区小菜蛾种群发生动态及其对常用杀虫剂的抗药性。结果表明:滇西菜区小菜蛾全年发生,为害期有9个月,春夏季为害重,3-6月为发生高峰期,2009-2015年最高诱蛾量为290~905头/7 d,小菜蛾种群对化学杀虫剂均产生了不同水平的抗药性,其中对阿维菌素和高效氯氰菊酯的抗药性最高,达到高水平抗药性,对多杀菌素、茚虫威和溴虫腈维持在中等水平抗药性,2011年对氯虫苯甲酰胺产生了28倍的抗药性,后恢复敏感,3年后又出现抗药性的上升趋势。可见,3-6月是滇西菜区小菜蛾防控的重要时期,可选择Bt、多杀菌素、茚虫威和溴虫腈等药剂轮换使用,减少氯虫苯甲酰胺使用次数,建议停用阿维菌素和高效氯氰菊酯。  相似文献   

15.
苦皮藤乳油对小菜蛾种群控制效应评价   总被引:2,自引:0,他引:2  
在室内外试验的基础上 ,应用生命表技术评价 1%苦皮藤 (CelastrusangulatusMaxim .)乳油对小菜蛾 (PlutellaxylostellaL .)种群的控制作用 ,结果表明 ,其控制作用主要表现在对成虫产卵的忌避作用和对幼虫的拒食作用。浓度 10 .0 0mL/L的苦皮藤液效果最佳 ,对成虫的忌避率为 73 2 % ,对幼虫的选择性和非选择性拒食率分别为 94 7%和 93 5 % ,小菜蛾种群趋势指数I值由对照的 2 1 6 140降为 0 6 6 84,干扰作用控制指数为 0 0 30 8。  相似文献   

16.
Abstract The larvae of Plutella xylostella feeding on cabbage plants treated by insecticides, nomolt (25 ×10-6 and cypermethrin (20× 10-6 were exposed to their parasitoid, Diadegma euerophaga in the field. The life table technique and the control efficiency (CE) were used to evaluate the sublethal effects of insecticides on the population dynamics of P. xylostella and D. euerophaga . The results showed that the CEs of nomolt and cypermethrin on D. eucerophaga were bigger than that on P. xylostella . Nomolt had a profound effects on D. eucerophaga by the food chain.  相似文献   

17.
Platynaspidius maculosus (Weise, 1910) (Coleoptera: Coccinellidae) is a ladybird beetle that preys on aphids and is distributed in China, Taiwan, and Vietnam. Recently, P. maculosus has invaded the southern parts of Japan; it was recorded on Okinawa Island in 1998, in Kagoshima Prefecture in 2006, and in Fukuoka Prefecture in 2010. In citrus groves in Shizuoka City, Central Japan in 2009–2012, the exotic ladybird was monitored by use of yellow sticky traps set inside citrus tree canopies. Adults of P. maculosus were captured in three out of the eight groves in 2010. This capture might be the first record of the ladybird from Honshu Island. Adults were trapped in three consecutive years, 2010–2012, in two groves; this suggests the possibility that the ladybird has become established in Shizuoka City. Adults were almost continuously caught on the traps from late April through October, being more abundant in early autumn (early September to early October), late spring (late April to mid-June), and mid-summer (early July to early August). During these periods, citrus shoots are growing and aphids are abundant. This finding suggests that the exotic ladybird might prey on citrus-infesting aphids, thereby reproducing in citrus groves. Based on the results obtained, potential impacts of the exotic ladybird on native aphidophagous ladybirds are also discussed.  相似文献   

18.

Background

Sero-prevalence is a valuable indicator of prevalence and incidence of A/H1N1 2009 infection. However, raw sero-prevalence data must be corrected for background levels of cross-reactivity (i.e. imperfect test specificity) and the effects of immunisation programmes.

Methods and Findings

We obtained serum samples from a representative sample of 1563 adults resident in Scotland between late October 2009 and April 2010. Based on a microneutralisation assay, we estimate that 44% (95% confidence intervals (CIs): 40–47%) of the adult population of Scotland were sero-positive for A/H1N1 2009 influenza by 1 March 2010. Correcting for background cross-reactivity and for recorded vaccination rates by time and age group, we estimated that 34% (27–42%) were naturally infected with A/H1N1 2009 by 1 March 2010. The central estimate increases to >40% if we allow for imperfect test sensitivity. Over half of these infections are estimated to have occurred during the study period and the incidence of infection in late October 2009 was estimated at 4.3 new infections per 1000 people per day (1.2 to 7.2), falling close to zero by April 2010. The central estimate increases to over 5.0 per 1000 if we allow for imperfect test specificity. The rate of infection was higher for younger adults than older adults. Raw sero-prevalences were significantly higher in more deprived areas (likelihood ratio trend statistic = 4.92,1 df, P = 0.03) but there was no evidence of any difference in vaccination rates.

Conclusions

We estimate that almost half the adult population of Scotland were sero-positive for A/H1N1 2009 influenza by early 2010 and that the majority of these individuals (except in the oldest age classes) sero-converted as a result of natural infection with A/H1N1 2009. Public health planning should consider the possibility of higher rates of infection with A/H1N1 2009 influenza in more deprived areas.  相似文献   

19.
Chlorantraniliprole is the first commercial insecticide from a new class of chemistry, the anthranilic diamides. Chlorantraniliprole provides an effective alternative insecticide for control of Plutella xylostella (L.) populations resistant to other insecticides. Baseline susceptibility to chlorantraniliprole for P. xylostella was surveyed previously from 16 geographical populations sampled from China during 2008-2009, and the median lethal concentrations (LC50s) varied among populations from 1.8- to 8.9-fold higher than the LC50 of a susceptible strain (Roth). In the present work, 20 field populations of P. xylostella sampled in 2010-2011 from China were tested with laboratory bioassays to determine if resistance to chlorantraniliprole had evolved in the field. The LC50s of the 14 populations from northern China ranged from 1.7- to 5.4-fold compared with the LC50 of Roth, which indicates these populations remain reasonably susceptible to chlorantraniliprole. However, the LC50s of the six populations from southern China (Guangdong Province) were 2.6-, 12-, 18-, 81-, 140-, and 2,000-fold higher than the LC50 of Roth. The results showed that high levels of resistance to chlorantraniliprole had evolved in field populations from Guangdong Province of southern China. Intensive use and misuse of chlorantraniliprole may be responsible for the rapid evolution of high-level resistance in P. xylostella in this region. The implementation of resistance monitoring plans and resistance management strategies is urgently needed in China to preserve susceptibility to chlorantraniliprole in P. xylostella.  相似文献   

20.
Abstract:  Predators are important biotic factors in the population dynamics of the diamondback moth, Plutella xylostella . A specific DNA marker was developed to detect P. xylostella in the gut contents of two polyphagous predators, Nabis kinbergii and Lycosa sp. A distinct 275-bp product was amplified by polymerase chain reaction (PCR) from the internal transcribed spacer (ITS-1) of the ribosomal gene of P. xylostella , but not from 11 other arthropod species collected from Brassica fields in South Australia. Fortuitously, the primer set could also amplify DNA products from two species and three varieties of Brassica plants, with the fragment size about 600 bp. When N. kinbergii was analysed after feeding a single fourth instar P. xylostella , 67% of individuals were positive with the 275-bp PCR product up to 16 h after feeding. Likewise, the PCR product was detected in 80% individuals of Lycosa sp. up to 72 h after feeding on a single fourth instar P. xylostella larva. Initial tests of samples collected from the field showed that the predation incidences for both N. kinbergii and Lycosa sp. determined by the 275-bp fragment corresponded to the density of P. xylostella in the field.  相似文献   

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