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1.
在昆明动物研究所和云南省思茅市大开河咖啡场进行了咖啡天牛的白僵菌防治试验。室内和田间试验结果表明,只要接触到白僵菌的各龄咖啡天牛,均可被感染致死;室内培养条件下的虫体一般在第15天左右致死率可达90%以上,室内木段堵孔到第20天累计死亡率达90%以上,室外插竹签,菌签插孔和菌泥堵孔法在第20天防治效也可达90%以上,手撒菌粉和喷菌液法虽有一定防治作用,但效果不显著,产量测定结果显示,生物防治区咖啡鲜果每0.067公顷(1/15ha.)比对照区高125.7kg;与几种常用杀虫剂防治费用比较认为,白僵菌是一种经济、安全的生物杀虫剂。  相似文献   

2.
研究表明,利用松毛虫赤跟蜂防治苹果小卷叶蛾、梨小食心虫;白僵菌处理地面.防治桃小食心虫的寄生效果,均可达90%左右,防治效果优于化学农药.赤眼蜂应掌握在害虫始卵期开始放蜂.5天1次,连放4次,每亩总放蜂量12万头.白僵菌应在桃小食心虫越冬代幼虫出土始盛期和盛期各防治1次,每次每亩用菌剂(100亿孢子/g)2kg.加25%对硫磷微胶囊剂0.15kg.兑水150kg,在树冠下地面喷洒.喷后覆草是提高防治效果的关键.  相似文献   

3.
思茅咖啡天牛种群构成与危害的时空特性研究   总被引:7,自引:1,他引:6  
通过室内饲养和野外调查,本文对思茅市咖啡天牛种群的构成,发生时期危害的时空特性及幼虫蛀孔部位的选择性进行了研究。结果表明,危害思茅地区咖啡的天牛种群由旋皮天牛和灭字虎天牛构成 ,在不同时间两个种群的构成比例不同。施皮天牛是优势种心化高峰期为4月18-30日,灭字虎天牛成虫主要在10-12月出现;在咖啡树中天牛幼虫的频数分布具有明显特征,1头虫的分布频数最高;  相似文献   

4.
以几丁质为底物,加入基本盐培养基中,诱导球孢白僵菌(Beauveriabassiana)产生分解昆虫表皮的蛋白酶。诱导物中,蝉蜕诱导的蛋白酶总活性、比活较高,经超滤、离子交换层析、亲和层析、制备性IEF电洗脱纯化了一种有凝乳弹性蛋白酶(Pr1)活性的蛋白酶BbPr1。经SDS-PAGE电泳银染后是单带,HPLC凝胶过滤显示单峰。BbPr1为单体酶,分子量为33.6kD左右,pI为7.4。底物专一性测定显示,BbPr1能水解Phe或Leu形成的酸胺键和肽键。BbPrl可被PMSF抑制,表明其活性中心有Ser残基;BbPr1还可被胰凝乳蛋白酶抑制剂TPCK和凝乳弹性蛋白酶抑制剂TEI等所抑制;胰蛋白酶抑制剂beupeptin和Epianstatin,及胃蛋白酶抑制剂Pepstain对BbPr1活性无影响。还研究了BbPr1的最适作用pH和pH稳定性。  相似文献   

5.
球孢白僵菌的紫外诱变及几丁质酶高产菌株的筛选   总被引:6,自引:0,他引:6  
以球孢白僵菌(Beauveriabassiana)1316为出发菌株,通过20min和30min的紫外线交替诱变分生孢子,采用透明圈法初筛和摇瓶培养复筛的方法,得到一突变株CH-1316。和原始菌株相比,该突变株的几丁质酶活力提高了近3倍,经传代培养,该菌株的几丁质酶高产特性能稳定遗传。  相似文献   

6.
以几丁质为底物,加入基本盐培养基中,诱导球孢白僵菌(Beauveria  相似文献   

7.
球孢白僵菌毒素的分离、毒力检测及结构鉴定   总被引:2,自引:0,他引:2  
用吸附法从球孢白僵菌(Beauveria bassiana)1003-V的代谢产物中分离出导致昆虫患病的毒素粗提物(以下简称毒素),并对其进行了毒力检测.结果表明,该毒素对白纹伊蚊(Aedes albopictus)幼虫有明显毒性;对棉铃虫(Heliothis zea)幼虫口服毒性较弱,血腔注射毒性较强;仅对革兰氏阳性细菌有抑菌作用.对草地夜蛾(Spodoptera frugiperda)Sf-21细胞株的毒力测定结果表明,毒力回归方程为y=2.03 2.39x,半致死浓度是0.01751%,其95%可信极限为0.01517%~0.0202%.高压液相色谱和红外光谱分析表明,该毒素含有三种在结构和性质上非常相近的物质.  相似文献   

8.
将高纯度球孢白僵菌分生孢子粉兑入一种含悬浮稳定剂及紫外保护剂的矿物油中,配成含孢量为100亿/ml的孢子悬乳剂(纯菌剂),再添加3%的吡虫啉10%可湿剂而得菌药混配剂,于2003年5月在浙江余姚进行了防治蔬菜蚜虫的田间药效试验和农户示范。在两块夏熟白菜地中,纯菌剂和菌药混配剂均用1000倍稀释液(107个孢子/ml)常规喷雾2次,并设清水对照和低用量吡虫啉对照。结果表明,混配剂在两块菜地的相对防效分别达94.5%和86.2%,纯菌剂分别达86.4%和73.1%,而低用量吡虫啉处理的最高防效仅为50%左右。在入夏豇豆、甘蓝、白菜、萝卜及梨树上用菌药混配剂1000倍稀释液对多种蚜虫进行的农户示范试验中,一次性喷雾后5~10d内对菜蚜防效为48%~68%,尤对梨二叉蚜的防效高达99%。在对含有和不含添加剂的两配方孢子悬乳剂进行的常温避光18个月贮存中,活孢率在头7个月均稳定在95%左右且未受配方影响,第10个月活孢率仍有75%左右。而后,含添加剂配方的活孢率下降加速,至16个月时基本失活;而不含添加剂配方的活孢率在第16、17及18个月时还有57%、51%和42%。  相似文献   

9.
家蚕病原球孢白僵菌的原生质体再生回复及核型分析   总被引:1,自引:0,他引:1  
时连根  徐俊良 《菌物学报》2000,19(2):223-229
家蚕病原球孢白僵菌(Beauveriabassiana)原生质体的分离制备、性状及再生回复,并用脉冲凝胶电泳(PFGE)技术分析了其核型。以6mg/mLDriselase为酶解液,0.7mol/LNaCl液(pH5.8)为渗透压稳定剂,在30℃下轻轻振荡处理幼嫩菌丝1.5h,是原生质体分离的适宜条件。原生质体的无核率为26.5%,有核率为73.5%,其中单核率为53.5%。再生回复的形式可观察到三种,其培养基的渗透压稳定剂以0.7mol/L葡萄糖较为适当。球孢白僵菌至少具有6条染色体,估算大小为2.5~6.6Mb,核型大小为26.5Mb。  相似文献   

10.
稻田生境调节和捕食性天敌对稻飞虱的控制作用   总被引:8,自引:4,他引:8  
广东省四会市大沙镇1973年开展以发挥天敌作用为主的水稻害虫综合防治,20多年来稻飞虱一直没有大发生,且发生程度低于临近地区。本文试图从理论上解释这一现象。通过改善天敌的生境条件,捕食性天敌群落种库中天敌的种类和多样性增多,天敌各落重建和发展的能力增强,重建后群落的种类数量和多样性均高于临近地区,最终使得天敌群落对稻飞虱的控制作用增强,98%以上的稻田飞虱的数量常在防治指标以下。  相似文献   

11.
白僵菌在松毛虫体上宿存侵染的电镜扫描观察   总被引:2,自引:0,他引:2  
通过扫描电子显微镜,观察了几种人工的或自然的环境下白僵菌在马尾松毛虫体上的宿存与侵染过程,描述了分生孢子的萌发和菌丝形成中的形态变化,讨论了致病效果与环境的关系,对林间应用提出了建议。结果表明:在25℃和95%的温湿度条件下,分生孢子萌发较快,萌发率和侵入率较高;白僵病的发生需要85%以上的相对湿度,这是自然环境中防治效果的制约因子;在松毛虫每年发生2~3代的我国林区,冬季放菌做法不宜提倡,6月份放菌更为适宜。  相似文献   

12.
球孢白僵菌[Beauveria bassiana(Bals.)Vuill.]野生型多孢株以及从其上分离的单孢株在不同培养基、光照、温度和湿度条件下继代培养,结果显示:无沦是多孢株还是单孢株,在传代中均发生显著的菌落局变,并产生形态各异的分离子,多表现为菌苔瘠薄或气生菌丝徒长,肉眼可见产孢量减少;尤其是单孢株菌落局变产生的分离子往往伴随着棕黄色或红棕色色素的分泌。培养基、温度、湿度和光照等环境因素对菌落局变产生具明显诱导作用。以SDAY培养基、偏低的温湿度和全光照条件下产生局变频率较低。大批量生产中以麦麸作原料较适宜。提出了菌落局变发生的几种可能的遗传机制。  相似文献   

13.
14.
试论拓宽生物防治范围,发展虫害可持续治理   总被引:1,自引:0,他引:1  
严毓骅 《昆虫学报》1998,41(-1):1-4
该文针对我国生物防治资源极其丰富和农民经济实力薄弱的特点,结合我国微孢子虫治蝗和苹果园植被多样化持续治理虫害的成果,论述了应如何发展和拓宽具有我国特色的害虫生物防治,进一步提高综合防治水平,促进农业可持续发展。  相似文献   

15.
在室内研究了分离自小猿叶甲的一株球孢白僵菌(SCAU-BB 01D)对小猿叶甲的致病力。结果表明,该菌株能感染小猿叶甲的成虫和各龄幼虫,但对不同虫期的致病力存在差异。在105~108孢子/m l的浓度范围内,随着处理浓度的升高,各虫期小猿叶甲的感病死亡率增加,在最高浓度1×108孢子/m l,处理后成虫第14天及1~3龄幼虫第10天的累计死亡率分别为84.7%、94.0%、96.0%和81.0%。用TDM模型对成虫和各龄幼虫的致病力数据进行模拟,所建模型均顺利通过Hosm er-L em eshow拟合异质性检验,表明模型拟合良好,并由模型估计出了该菌株对小猿叶甲各虫期的致死剂量与致死时间。在处理后第10天,成虫和1~3龄幼虫的致死中浓度(LC50)分别为2.68×107、1.07×106、1.63×105孢子/m l和8.31×106孢子/m l,而第14天成虫的LC50为2.38×106孢子/m l。随着浓度的增加,各虫期所需的感病死亡时间缩短,在最高浓度1×108孢子/m l,球孢白僵菌对小猿叶甲成虫及1~3龄幼虫的致死中时(LT50)分别为9.28、4.29、4.40d和5.06 d。综合分析白僵菌对各虫期的致死剂量及致死时间可以看出,不同虫期的小猿叶甲对球孢白僵菌敏感性不同。结果表明该菌株在小猿叶甲生物防治中具有一定的潜力。  相似文献   

16.
The potato tuber moth, Phthorimaea operculella, is the most damaging potato pest in the world and is difficult to control as the larvae are internal feeders in the foliage and tubers. Entomopathogenic fungi that colonize plants as endophytes have lethal and sublethal pathological effects on insect pests. We show that Beauveria bassiana colonizes the aerial parts of potato plants endophytically after inoculation through soil drenching. Endophytic B. bassiana persisted in potato foliage for more than 50 days postinoculation. Bioassays indicated that foliage of B. bassiana-inoculated potato plants were pathogenic against larvae of P. operculella. Sublethal experiments indicated that B. bassiana negatively affected the growth, development, and reproduction of P. operculella. Development experiments showed that the weight of P. operculella pupae reared on B. bassiana-colonized potato plants (4.25 mg) was significantly less than that of those reared on uninoculated control plants (8.89 mg). Compared with newly eclosed larvae fed on control plants, those fed on B. bassiana-inoculated plants had significantly lower survivorship, with only 17.8% developing to the adult stage. Oviposition of P. operculella females reared on B. bassiana endophytically colonized plants was significantly lower (35 eggs/female) than of those reared on uninoculated plants (115 eggs/female). This study demonstrates that endophytic B. bassiana can be a potential biological control agent for the control and management of P. operculella. Comparing pupal weights of P. operculella reared on potato plants inoculated with the B. bassiana strain GZGY-1-3 and on untreated control plants, pupae from the control plants were significantly heavier than those from treated plants.  相似文献   

17.
中国很重视害虫生物防治,但与欧美国家相比,对更经济有效的传统生物防治重视较少。对那些源于外国、特别是最近从国外侵入的害虫来说,传统生物防治更是一本万利。本文列举了174种中国南方的有害节肢动物及它们在外国的分布和可能的发源地。还举出了分布于中国南方的6种害虫及5种杂草在外国传统生防成功的情况。  相似文献   

18.
Five Beauveria bassiana strains were evaluated for control of western flower thrips. Strain RSB was the most virulent, causing 69–96% mortality at concentrations of 1×104–1×107 conidia mL?1, 10 days after inoculation of first instars. In greenhouse trials, RSB applied to broccoli foliage significantly reduced adult and larval populations.  相似文献   

19.
A standard bioassay method for assessing the pathogenicity of Beauveria bassiana (Balsamo) Vuillemin (GHA strain) against second instar tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Hem., Miridae) was developed. Several types of inoculation methods, assay containers and incubation times were tested. Our goal was to minimize control mortality and maximize treatment mortality. Five inoculation methods (immersing broccoli florets or bean pods, spraying broccoli florets or bean pods, and immersing insects) and four types of plastic containers (114‐, 171‐, 228‐ and 455‐ml) were tested. Immersing insects directly in a fungal suspension was the most effective inoculation method, which resulted in a treatment mortality of 70–81.3% at a concentration of 1 × 107 conidia/ml. The 114‐ml plastic container was the most suitable assay container when 10 tarnished plant bug nymphs were treated together, resulting in a control mortality of only 6% 12 days after treatment. Within the first 6 days after treatment, 71.1% of the insects were killed, compared with a total mortality of 81.3% after 12 days. Nymphs infected with the test fungus changed colour from green to black. Mycelial outgrowth and sporulation on the cadavers demonstrated that most nymphs died of fungal infection. A total of 61.1 and 80.5% of the cadavers showed signs of mycelial outgrowth 9 days after death among those that were surface sterilized and those that were not, respectively.  相似文献   

20.
Abstract:  In laboratory bioassays, the efficacy of the entomopathogenic fungus Beauveria bassiana against the spruce bark beetle, Ips typographus , was tested under various conditions. Four of the tested isolates and the commercial product Boverol® caused 99–100% mortality when tested at a concentration of 1.0 × 107 conidia/ml at 25°C. Using B. bassiana isolate 138 at a concentration of 1.0 × 106, the median survival time (MST) was 6.1 d and significantly longer compared with the MST of 4.2 and 4.0 d at 1.0 × 107 and 1.0 × 108 conidia/ml, respectively. In the next experiment, the beetles were maintained on spruce bark, filter paper or artificial diet during the bioassay with Boverol®, and significant differences in the MST of 3.6, 2.5 and 5.3 d, respectively, were noticed. The experiment with Boverol® at different temperatures showed that the beetles lived significantly longer at 15°C (MST 8.7 d) than at 20, 25, 30 and 35°C. At 25°C, the beetles died most rapidly (MST 3.5 d). At different relative humidities (RH) of 40, 70 and 100%, nearly all beetles were dead after treatment with a suspension of Boverol® at 1.0 × 107 conidia/ml. At 40% RH, 49% of the untreated beetles died after 7 d. The best effects were achieved with the following bioassay: beetles were fed for three days on artificial diet, then dipped into a solution of 1.0 × 107 conidia/ml and transferred on a piece of spruce bark in Petri dishes at 25°C and 70% RH.  相似文献   

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