寒区昆虫病原线虫对韭菜迟眼蕈蚊的防治研究

结合室内生测、温室盆栽和大棚内小区试验的方法,探讨了寒区昆虫病原线虫(entomopathogenic nematode,EPN)对我国北方越冬韭菜迟眼蕈蚊Bradysia odoriphaga Yang et Zhang的防治作用。室内生测的结果显示,在侵染剂量为400条侵染期线虫(IJs)每头3龄幼虫或蛹时,异小杆线虫Heterorhabditis bacteriophora ZT(HbZT,哈尔滨市植物园分离株)、H.bacteriophora LG(Hb-LG,辽宁分离株)、H.bacteriophora NJ(Hb-NJ,美国新泽西分离株)和斯氏线虫Steinernema carpocapsae All(Sc-All)对迟眼蕈蚊3龄幼虫的致死率于72 h后均达100%,而对蛹的寄生效果则是Hb-ZT线虫最高;Hb-ZT与Sc-All(1∶1)混用,对幼虫的室内寄生效果高于单独施用2个线虫的寄生效果;温室盆栽试验中喷施Hb-ZT与Sc-All(1∶1)的线虫混合液,施用剂量减半(50万IJs/m2),对韭蛆成虫羽化的控制效果稍高于单独施用2个线虫(100万IJs/m2)效果;不同时期防治韭蛆的试验结果表明,于韭菜棚内发现韭蛆成虫5¹0 d内喷施线虫的防治效果较好;韭菜大棚内喷施剂量为50万IJs/m2的Hb-ZT与Sc-All线虫混合液对韭蛆幼虫防效达100%,增产作用与常规化学药剂(辛硫磷)相当。     

化学杀虫剂对昆虫病原线虫侵染韭菜迟眼蕈蚊能力的影响

【目的】为提高昆虫病原线虫对韭菜迟眼蕈蚊Bradysia odoriphaga的防治效果,将昆虫病原线虫与环境友好型化学杀虫剂混用是一条有效途径。【方法】本研究测试了70%吡虫啉水分散颗粒剂、40%毒死蜱乳油和4.5%高效氯氰菊酯乳油对昆虫病原线虫Heterorhabdits bacteriophora Taishan strain H06品系、Steinernema carpocapsae strain SF-SN和All品系存活及侵染率的影响,及低剂量化学杀虫剂与昆虫病原线虫混用对韭蛆3龄幼虫的作用效果。【结果】高效氯氰菊酯(含量为2.00、0.40、0.20和0.10μg·mL-1)和吡虫啉(25.00、5.00、2.50和1.25μg·mL-1)对H.bacteriophora H06和S.carpocapsae All的存活无显著影响,3品系线虫毒死蜱(8.00μg·mL-1)对3品系线虫的致死率均显著高于对照;不同浓度的毒死蜱对3品系线虫的致死率存在显著差异。3种药剂分别与3品系线虫混合后处理韭蛆,韭蛆的死亡率明显高于线虫和杀虫剂单用处理。药后3 d,SF-SN与毒死蜱(8.00μg·mL-1)、吡虫啉(25.00μg·mL-1)和高效氯氰菊酯(2.00μg·mL-1)混合处理韭蛆,分别比单用杀虫剂提高防效34.20%、21.18%、54.99%,优于另外两种线虫与3种药剂混用的效果。【结论】供试线虫中,SF-SN品系与上述杀虫剂联合防治韭蛆效果最好。     

噻虫嗪对昆虫病原线虫侵染韭菜迟眼蕈蚊能力的影响

【目的】为提高昆虫病原线虫对韭菜迟眼蕈蚊Bradysia odoriphaga Yang et Zhang幼虫的防治效果,将昆虫病原线虫与环境友好型化学杀虫剂混用是一条有效途径。【方法】测定了噻虫嗪与6个昆虫病原线虫品系混用对韭菜迟眼蕈蚊的作用效果,以及温度和土壤含水量对作用效果的影响,并进行了田间验证。【结果】田间推荐浓度噻虫嗪(100 mg·L~(-1))对6种供试线虫存活无显著影响。处理后3 d,低浓度噻虫嗪(15 mg·L~(-1))分别与6品系线虫混合后处理韭菜迟眼蕈蚊幼虫,其死亡率明显高于线虫和噻虫嗪单用处理。小卷蛾斯氏线虫SF-SN+噻虫嗪、印度异小杆线虫LN2+噻虫嗪和小卷蛾斯氏线虫All+噻虫嗪3种组合发挥杀虫作用的最适温度范围分别为20~25℃、25~30℃和25~30℃,显著高于其他温度;最适土壤含水量范围为10%~18%,也显著高于其他湿度。大田条件下,施用后7 d,单用噻虫嗪、线虫+噻虫嗪组合处理对韭菜迟眼蕈蚊的防治效果显著高于单线虫,且以芫菁夜蛾斯氏线虫SF-SN+噻虫嗪的防治效果最高,达到93%以上。【结论】芫菁夜蛾斯氏线虫SF-SN品系与噻虫嗪组合联合防治韭菜迟眼蕈蚊效果最好。     

韭菜迟眼蕈蚊体内及韭菜根际微生物的多样性分析

【目的】为了了解韭菜迟眼蕈蚊Bradysia odoriphaga生存环境中微生物的多样性。【方法】本研究对韭蛆、韭菜鳞茎、根部以及土壤中的微生物进行分离纯化,对部分代表性细菌进行了生理生化特征的分析,并对分离得到的真菌及细菌分别采用ITS和16S r DNA基因分析的方法进行鉴定。【结果】总共分离鉴定出25种微生物,在韭菜鳞茎和土壤中分别分离出半知菌亚门(Deuteromycotina)的球孢白僵菌Beauveria bassiana和球孢虫草Cordyceps bassiana两种真菌,在韭蛆体内、韭菜鳞茎、韭菜根部以及土壤中分别分离出10、15、9、6种细菌,以变形菌门(Proteobacteria)和厚壁菌门(Firmicutes)细菌为主,其余的细菌分别属于放线菌门(Actinobacteria)和拟杆菌门(Bacteroidetes)。【结论】本研究可以为寻找韭菜、韭蛆和微生物三者之间的协同进化关系提供理论基础,并期望为韭蛆的共生防治提供指导。     

营养物质和水分对韭菜迟眼蕈蚊成虫繁殖和寿命的影响

【目的】研究韭菜迟眼蕈蚊Bradysia odoriphaga成虫对营养物质的选择补充习性,找出对其产卵繁殖起重要作用的关键因子,为其有效防控提供依据。【方法】通过室内成虫单独配对试验,研究不同营养物质(花粉、蜂蜜、维生素、糖、醋、酒)和水分对韭菜迟眼蕈蚊成虫繁殖和寿命的影响。【结果】随着花粉、蜂蜜和维生素浓度的增加,成虫的繁殖力下降;糖醋酒液单一成分和混合液对成虫繁殖和寿命的影响与水分相近;补充供试营养物质和水分对韭菜迟眼蕈蚊的繁殖力均明显高于干燥对照。补充水分的成虫繁殖力最高,产卵率超过70%,单雌平均产卵量达70粒,雌雄成虫寿命最长均超过3 d。土壤湿度对产卵有显著影响,土壤相对湿度为40%和50%时,成虫的落卵率超过25%,落卵量大于480粒,显著高于其它湿度(P<0.05)。【结论】水分是影响韭菜迟眼蕈蚊成虫繁殖和寿命的关键因子,供试的营养物质对韭菜迟眼蕈蚊繁殖没有促进作用,因此在韭菜迟眼蕈蚊成虫盛发期可以通过控制田间土壤湿度来影响韭菜迟眼蕈蚊繁殖。     

五种细菌侵染后韭菜迟眼蕈蚊体内防御反应的研究

为了解韭蛆体内5种细菌对韭菜迟眼蕈蚊Bradysia odoriphaga的影响,本研究将解淀粉芽孢杆菌Bacillus amyloliquefaciens、居泉沙雷氏菌Serratia fonticola、恶臭假单胞杆菌Pseudomonas putida、枯草芽胞杆菌Bacillus subtilis和节杆菌Arthrobacter nitroguajacolicus 5种细菌通过浸泡和针刺两种方式对韭蛆进行侵染,观察韭蛆存活率、蛋白含量以及3种抗氧化酶活性的变化规律。结果显示,与浸泡接种细菌相比,针刺接种细菌后,韭蛆整体的存活率和SOD酶活性下降,而蛋白含量、POD活性和CAT活性上升。其中,居泉沙雷氏菌在针刺侵染后对韭蛆表现出致病性。因此,机械损伤对于细菌的侵染具有重要的作用,韭蛆则可通过改变抗氧化酶的活性来防御细菌的侵染。本研究为探索韭蛆与体内共生微生物之间的关系提供重要的基础,为韭蛆的共生防治提供指导。     

昆虫病原线虫应用研究概况

大规模工厂化离体培养技术的发展,活跃了昆虫病原线虫的实际应用研究.近20年来在生物防治实践和产业化方面已经取得了令人鼓舞的进展,已成为当前国际生防领域研究热点之一.我国在昆虫病原线虫的实际应用方面也进行了大量研究.本文从昆虫病原线虫对土栖性、钻蛀性和叶面害虫的防治效果,以及影响线虫应用的环境因子的分析,简要概述了昆虫病原线虫的应用进展,并探讨昆虫病原线虫进一步应用的前景.     

韭菜田中常用化学农药对昆虫病原线虫

本文研究了韭菜Allium tuberosum Rottle ex Spreng田常用化学农药辛硫磷、毒死蜱、高效氯氰菊酯、阿维菌素、敌敌畏、三唑酮、菌核净、多菌灵在田间推荐使用浓度及高一倍浓度条件下对Heterorhabditis bacteriophora H06和Hindica LN2线虫存活及感染力的影响,测定了农药与昆虫病原线虫施用间隔时间对线虫感染力的影响。结果显示,高效氯氰菊酯、三唑酮、菌核净和多菌灵对Hbacteriophora H06和Hindica LN2的存活及感染力无显著影响,可与这两种线虫共同使用;敌敌畏对两种线虫有显著致死作用,应严禁使用;辛硫磷、毒死蜱和阿维菌素对Hbacteriophora H06的存活无显著影响,对Hindica LN2具有一定的致死作用,但影响这两种线虫的感染力,这三种农药分别施用10 d、10 d、20 d后则对线虫感染力没有影响,可施用线虫。     

韭菜迟眼蕈蚊的室内人工饲养技术

韭菜迟眼蕈蚊 Bradysia odoriphaga Yanget Zhang俗名韭蛆 ,是危害韭菜的主要害虫 ,亦可危害葱、蒜等作物。该幼虫群集在韭菜鳞茎处咬食 ,常造成韭菜大量死亡 ,严重发生地块可减产 5 0 %以上。目前生产上防治韭蛆常用对硫磷、甲拌磷等高毒药剂灌根防治 ,会造成食用者中毒事件。在进行防治韭蛆低毒药剂筛选工作中 ,需要大量虫龄一致的幼虫进行室内试验 ,作者经过多年的实践探索 ,研究出了一套韭菜迟眼蕈蚊室内人工饲养技术 ,现简介如下。1　材料与工具1 .1　直径 2 0 cm的花盆若干。1 .2　直径 1 2 cm、高 2 0 cm的玻璃罩 ,或用聚丙烯做成…     

昆虫病原线虫与粘合剂混用的增效试验

应用一定浓度的水溶性粘合剂POA与病原线虫混合,可提高线虫的存活率、毒力及对寄主的致死速度.LRT50为0.74,共毒系数大于100,混剂增效显著.田间防治龟背天牛、桑天牛的效果比单用病原线虫提高10-25%.POA是一种有利用价值的增效剂.     

ADVANCES IN THE RESEARCH OF ENTOMOPATHOGENIC NEMATODES STEINERNEMA AND HETERORHABDITIS IN CHINA

Abstract  The current status of Steinernema and Heterorhabditis entornopathogenic nematode research in China was reviewed in the collection and identification, the application in pest control programmes, symbiotic bacteria and mass production.     

中国昆虫病原斯氏和异小杆线虫的研究概况(英语)

昆虫病原斯氏和导小杆线虫作为生物防治因子已受到世界各国的广泛重视,并得到了商品化的发展.自50年代,特别是7O年代末,我国从原捷克斯洛伐克、澳大利亚、美国等地引进了大批昆虫病原斯氏和异小杆线虫.同时也从土壤或自然寄主中分离出许多本国线虫种或品系,并对此类线虫进行了全面的研究,在昆虫病原线虫的种类调查和鉴定、田间大面积应用、安全性、共生细菌、大量繁殖等方面取得了可喜的进展.本文将综述这些方面的研究概况.     

拟双角斯氏线虫生物学特性的研究

本文对拟双角斯氏线虫Ｄ－４－３品系的生物学特性进行了研究。     

几种因素对电刺激诱导小鼠卵母细胞孤雌活化的影响

为了给小鼠体细胞核移植研究提供最佳的小鼠卵母细胞电激活条件 ,研究了影响电刺激诱导小鼠卵细胞孤雌活化的 4个因素 :脉冲强度、电融合液、操作液预处理及小鼠品系。发现 :(1)小鼠卵母细胞在 0 5～1 2 5kV/cm脉冲强度下 ,获得的活化率差异不显著 (71 4 3%～ 80 39% ,P >0 0 5 ) ,而在 1 5kV/cm的脉冲刺激下 ,活化率显著下降至 4 8 15 % (P <0 0 5 ) ,死亡率显著升高 (2 9 6 3% ,P <0 0 5 ) ;(2 )含有山梨醇的EFS1和含有甘露醇的EFS2对小鼠卵母细胞的活化效果相似 ,但前者较后者更易于操作 ,可以用EFS1取代EFS2运用于小鼠体细胞核移植研究中 ;(3)用核移植操作液预处理小鼠卵母细胞后 ,在 0 75kV/cm的脉冲强度下 ,与对照组无差异 ,而当脉冲强度升至 1 0kV/cm时 ,活化率显著降低 (46 6 7% ,P <0 0 5 ) ,而死亡率显著升高(30 0 0 % ,P <0 0 5 ) ;(4)昆明白小鼠和C5 7BL/ 6小鼠卵母细胞在 0 75～ 1 0kV/cm场强下 ,活化率无差异。     

中国昆虫病原线虫一新纪录

采用分子生物学和形态学相结合的方法,对采自广东省翁源县的编号为GDa71的昆虫病原线虫进行分类鉴定.该线虫各虫期的主要形态特征、测量值以及基于ITS1和部分28S rDNA两段序列,分别构建系统进化树均显示它与印度异小杆线虫Heterorhabditis indica相似,是后者的一个品系,为中国新纪录.     

FACTORS AFFECTING THE VERTICAL DISTRIBUTION OF RHIZOCTONIA SOLANI WITH SPECIAL REFERENCE TO CO2 CONCENTRATION

Durbin , Richard D. (U. Minnesota, St. Paul.) Factors affecting the vertical distribution of Rhizoctonia solani, with special reference to CO₂ concentration. Amer. Jour. Bot. 46(1) : 22-25. Illus. 1959.—Thirty-three heterogeneous clones of 3 ecological types of Rhizoctonia solani (aerial, surface, and subterranean, based on their vertical distribution on the host plant) were grown in flowing atmospheres containing various levels of CO₂. The linear growth rates were compared with those obtained when the clones were grown in normal air. Significant differences were found among the clones with respect to their tolerance of CO₂. Those found normally in the soil were more tolerant of CO₂ than were clones occurring in either surface or aerial environments. Additional experiments with other plant pathogenic soil fungi, plus data obtained from the literature, indicate that tolerance of CO₂ is a common attribute of fungi normally found in the soil and in rotting organic matter, environments where high CO₂ concentrations are to be expected. Significant differences were also found in the linear growth rates of 86 clones from the 3 types. The ratio of the mean growth rates for aerial, surface, and subterranean clones was about 4:3:2, respectively. The 2 characteristics, linear growth rate and CO₂ tolerance, were negatively correlated (r = +.773). The percentage of the aerial, surface, and subterranean types producing sclerotia was 82, 48, and 21, respectively. In 9 clones tested linear growth rate was not found to be correlated with endogenous O₂ uptake rate. Carbon dioxide tolerance, linear growth rate, and sclerotial formation are characteristics which seem to play a part in determining the habitat of clones of this fungus.     

FACTORS AFFECTING THE INTRACELLUALR SYNTHESIS OF KYNURENINE

Near the time of pupation, autofluorescent kynurenine globules appear in the cells in the anterior region of the fatbody of Drosophila melanogaster. It has been reported previously that kynurenine synthesis may be induced in an additional group of fat cells by feeding the precursor tryptophan to Drosophila larvae, and that this induction of kynurenine production viewed within the fat cells is correlated with an increase in tryptophan pyrrolase activity. In the present report, conditions are outlined which result in the appearance of kynurenine in all of the fat cells. The number of cells in the fatbody which contain kynurenine is influenced by the quantity of tryptophan included in the diet, as well as by the developmental stage at the time of treatment and the duration of the feeding period on the inducer. Physical barriers modifying permeability, such as the membranous layer noted surrounding the fatbody, may be a factor in the regulation of the time and nature of the cellular induction of kynurenine synthesis. Another factor to be considered is the possibility of interference with the availability of tryptophan as a substrate or inducer for this synthesis within the cell. It is suggested that the occurrence of pteridines in some of the fat cells may modify the response of these cells to produce kynurenine, since pteridines as electron acceptors can complex with tryptophan as an electron donor. Kynurenine may be produced in the fat cells under in vitro conditions when they are incubated with L-tryptophan, but kynurenine is not formed when fat cells are incubated with D-tryptophan. The in vitro studies further demonstrate that induction of kynurenine synthesis may occur in fat cells isolated from young larvae in contrast, to in vivo conditions in which inducer does not effect an earlier appearance of kynurenine in the larval fatbody.