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101.
102.
The tomato zonate spot virus (TZSV) is responsible for substantial yield losses in vegetables, tobacco and other cash crops in China in recent years. The western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera, Thripidae), is the main vector of TZSV in Yunnan Province. Because controlling the population of insect vectors is the most efficient way to prevent epidemics of viral diseases, we conducted laboratory assays to assess the potential of using spirotetramat as an alternative to imidacloprid in controlling F. occidentalis. Our results demonstrated that spirotetramat was significantly more lethal than imidacloprid to F. occidentalis at different concentrations. The LC30, LC50 and LC90 values of spirotetramat were all much lower than those of imidacloprid after the same time of treatment. Frankliniella occidentalis was more sensitive when treated with spirotetramat than imidacloprid at the concentrations of 500, 250, 125 and 62.5mg/L, and the median lethal concentrations (LC50) were 285.53, 82.24 and 11.19mg/L at 12, 36 and 72 hours after treatment, respectively. Spirotetramat caused 100% mortality of F. occidentalis at 500 and 250 mg/L after 48 hours treatment, and at the lowest concentration 125 mg/L at 72 hours after treatment, respectively. Field experiments carried out elsewhere have confirmed our findings. Together they allow us to conclude that spirotetramat is a promising pesticide for the control F. occidentalis in China.  相似文献   
103.
蓟马类害虫综合治理研究进展   总被引:7,自引:1,他引:6  
蓟马是缨翅目(Thysanoptera)昆虫的统称,虫体微小,常隐匿于花与嫩叶中为害。蓟马繁殖力强,世代重叠严重,爆发频次高,全球贸易和气候变暖加速了蓟马害虫的扩散和为害,蓟马类害虫已逐渐成为世界上最重要的农业害虫类群之一。国内外有关蓟马害虫的发生为害及防治方面的研究已有许多报道,但缺乏系统性归纳总结。笔者分别从蓟马生物生态学特性、发生为害现状及综合防治技术3个方面进行了综述,并对蓟马害虫的综合治理进行了展望,提出了协调使用生物防治、物理防治与化学防治,以及合理利用农业防治的综合防治技术体系是实现蓟马害虫综合治理的重要途径。  相似文献   
104.
苜蓿蓟马的发生规律和药剂防治试验   总被引:9,自引:0,他引:9  
在陕西关中地区研究了苜蓿蓟马优势种群、种群数量、危害特征、田间消长规律等。结果显示:牛角花齿蓟马(Odontothripsloti)是优势种;蓟马主要危害第二、三茬苜蓿,7~8月份是苜蓿蓟马若虫的发生危害高峰期。选用高效氯氰菊酯、吡虫啉、艾美乐和围打蓟虱蚜4种药剂防效比较表明,高效氯氰菊酯的防治效果最好,持效期长,成本低。  相似文献   
105.
水稻叶色突变对虫害发生影响的研究初报   总被引:1,自引:0,他引:1  
为明确叶色标记水稻在生产中可能引起的虫害发生变化,本试验在使用和不使用农药防治的情况下,以常规品种嘉禾218为对照,对龙特甫B及其2个叶色突变系黄玉B、翠玉B田间虫害情况进行了调查.龙特甫B为正常绿叶籼稻品种,黄玉B、翠玉B全生育期分别表现黄色和翠绿色,在苗期、分蘖期和抽穗期,黄玉B较龙特甫B的叶绿素含量分别下降58.O%,48.4%和40.8%,翠玉B则分别下降39.5%,36.0%和29.5%.结果表明,秧田期2个叶色突变体上的稻蓟马虫量显著高于其亲本龙特甫B;本田期灰飞虱和褐飞虱的虫口数在不同材料间或差异不显著,或存在显著差异,但没有一定的规律性.但是,2个突变体受稻纵卷叶螟的危害显著轻于龙特甫B,表现为盛发期突变体受稻纵卷叶螟危害产生的虫苞数显著少于龙特甫B,而龙特甫B与嘉禾218之间没有显著差异;相反,2个突变体植株上白背飞虱的虫量显著大于龙特甫B,龙特甫B也显著大于嘉禾218.根据植株的农艺性状和叶绿素含量,以及虫害发生动态变化,笔者推测,造成叶色标记水稻稻纵卷叶螟危害变轻的原因可能与植株叶绿素含量下降,影响幼虫生长发育有关,但引起白背飞虱虫口增加的原因尚需进一步研究.本试验为首次对叶色标记水稻虫害发生情况进行研究,所得结果不但对完善叶色标记水稻生产体系具有指导意义,同时对研究害虫与水稻叶色之间的关系也具有理论价值.  相似文献   
106.
Maize Lethal Necrosis Disease (MLND) has emerged as a great threat to maize production in East Africa. It is caused by a synergistic infection of maize by sugarcane mosaic virus (SCMV) and maize chlorotic mottle virus (MCMV). This study was carried out in Bomet County, Kenya, to determine the potential of various cropping systems to manage vectors of MLND–causing viruses. Plots measuring 7.5 m × 5.25 m were planted with maize (Zea mays L.) intercropped or bordered by elephant grass (Pennisetum purpureum Schumach.), coriander (Coriandrum sativum L.), pearl millet (Pennisetum glaucum (L.) R. Br.) and Gadam sorghum (Sorghum bicolour (L.) Moench). Maize monoculture was used as a control treatment; the nine treatments were arranged in a randomized complete block design and replicated four times for two seasons (December 2014 to April 2015 and April 2015 to September 2015). Data on corn thrips and corn leaf aphid infestation, MLND severity and incidence, MCMV and SCMV viral load, and yield were recorded. The sorghum border was the only companion crop that tested positive for MCMV and none tested positive for SCMV. Maize intercropped with elephant grass had significantly (P?<?0.01) the least incidence of disease. However, this treatment produced significantly lower yields (P?<?0.01). Coriander was the only companion plant most preferred by both corn thrips and corn leaf aphids (P?<?0.001). Maize from all cropping systems tested positive for MCMV (P?<?0.001) while maize grown with coriander tested negative for SCMV (P?<?0.001). Yields from plots surrounded by sorghum and coriander were significantly similar to those from maize monoculture plots. These findings suggest that maize should be intercropped with coriander due to its potential to trap corn leaf aphids and protect maize from SCMV. In addition maize should be grown surrounded by a sorghum border to maximize yield in areas where MLND is prevalent.  相似文献   
107.
通过观察研究,澄清了玉米蓟马在洛阳市的优势种为禾蓟马和稻管蓟马,明确了影响发生的主 要因子是降雨、日照、玉米播期和栽培措施等,提出了可行的综合防治措施。  相似文献   
108.
Studies were carried out on a population ofThrips tabaci Lindeman (Thysanoptera: Thripi-dae) from Liguria to assess its sex-ratio and its ability to transmit four tospoviruses: tomato spotted wilt (TSWV), impatiens necrotic spot, tomato chlorotic spot and groundnut ringspot. The population was composed of females only (therefore thelytokous). The first instar larvae were allowed to acquire the virus for 48 h on infected leaves of datura, basil or pepper, and then reared on cucumber until emergence, which medially occurred 9.5 days after hatching. Transmission capacity was checked using two inoculation access periods (lAPs) of 48 h each on pepper leaf disks.T. tabaci was able to transmit TSWV isolate P105 with an efficiency of 16.7% and 4.4% in the first and second IAP, respectively, and TSWV isolate BR-01 with an efficiency of 2.0%. The onion thrips did not transmit the three other tospoviruses. During the IAPs, almost all adults fed on the leaf disks, producing evident silvery scars. The presence of tospovirus nucleocapsids in thrips was assayed by Triple Antibody Sandwich (TAS) and cocktail ELISA. Not all adults that had transmitted TSWV were positive in the tests, whereas some non-transmitter individuals proved positive. For each of the other tospoviruses, some thrips were positive in at least one test, although none was able to transmit the virus.  相似文献   
109.
昆明市白车轴草上蓟马种群动态调查   总被引:3,自引:0,他引:3       下载免费PDF全文
对昆明市白车轴草上蓟马种类及其周年种群动态进行了调查。白车轴草上蓟马主要有西花蓟马(Fran-kliniella occidentalis)、丽花蓟马(F.intonsa)、八节黄蓟马(Thrips flavidulus)、端大蓟马(Megalurothrips distalis)、稻单管蓟马(Haplothrips aculeatus)和烟蓟马(T.tabaci),有时会出现黄胸蓟马(T.hawaiiensis)、玉米黄呆蓟马(Anaphothrips obscurus)、苏丹呆蓟马(A.sudanensis)和云南纹蓟马(Aeolothrips yunnanensis)。本文分析了前6种蓟马的周年种群动态,重点阐述了外来有害生物西花蓟马,该虫主要在3~6月发生,是此期间白车轴草上的蓟马优势种。  相似文献   
110.
40个苜蓿品种(系)对蓟马田间抗性评价   总被引:4,自引:0,他引:4  
以受害指数为标准,在兰州对来自国内外40个苜蓿品种(品系)进行了田间抗蓟马评价试验。田间蓟马种类以牛角花齿蓟马为主,占田间蓟马混合种群数量的80%以上。结果表明,所有苜蓿品种(品系)的受害指数分布范围为65.89%~88.03%,受害指数在70%以下的有天水、Super7、L287、Eureka和豫县;天水苜蓿抗性最强,受害指数最小,为65.89%,与其他品种有显著差异;准葛尔受害指数最高,为88.03%。对不同品种苜蓿的受害指数与株高和虫口数量的相关分析表明,受害程度与株高及虫量无关。同时,本研究也提出了田间苜蓿受蓟马为害的测定标准及抗性评价方法。  相似文献   
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