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1.
昆虫化学信息物质以其微量i高效、无污染、与农药兼容等特点而成为当前世界各国昆虫学家研究的热点问题,它们的应用范围非常广泛,本文对昆虫化学信息物质的概念进行了综述,阐述了其包含的种类的相互关系和相应的概念以及在农、林业害虫领域中的应用效果,展望了昆虫化学信息物质的发展前景。  相似文献   
2.
性外激素诱发中华乌塘鳢产卵的初步研究   总被引:7,自引:0,他引:7  
洪万树 《水产学报》2004,28(3):225-230
在陶瓷人工产卵管道内吊挂性外激素的研究表明,卵巢提取液对雄鱼的吸引作用大于雌鱼,而精巢和贮精囊提取液对雌鱼的吸引作用则大于雄鱼,17α-P、17α,20β-P和PGE2对雌鱼和雄鱼均具有相似的吸引作用。雌鱼在管道内的产卵次数、产卵量以及成熟卵的受精率均与产卵管道内吊挂的性外激素种类有关,17α,20β-P和PGE2两个实验组产卵次数最多,其中PGE2实验组的产卵量和受精率最高。17α-P在贮精囊和精巢提取液中的含量显著高于卵巢提取液(P<0.05);贮精囊提取液中PGE2和PGF2α的含量分别显著高于精巢提取液和卵巢提取液(P<0.05);提取液中PGE2和PGF2α的含量均依次为贮精囊提取液>精巢提取液>卵巢提取液。卵巢提取液刺激雄鱼所引起的平均EOG高于雌鱼,而精巢和贮精囊提取液刺激雌鱼所引起的平均EOG高于雄鱼,雌鱼和雄鱼对17α-P、17α,20β-P、PGE2和PGF2α刺激所产生的平均EOG,以PGE2为最高。  相似文献   
3.
OBJECTIVE: To evaluate whether a synthetic analogue of feline facial pheromone (FFP) calms cats before, and reduces struggling during intravenous catheterization. DESIGN: Block-randomized, 'blinded' clinical trial. ANIMALS: Seventy-seven healthy cats presented for elective surgery. PROCEDURE: Cats given glycopyrrolate and oxymorphone were assigned to one of four treatments: acepromazine and exposure to FFP (aceFFP); acepromazine and exposure to a placebo (acePlac); exposure to FFP only (FFP) and exposure to placebo only (Plac). The behaviour of cats was recorded on videotape for evaluation by assessors unaware of treatment group. Cats' veins were then catheterized by veterinary students unaware of the study protocol. Based on each cat's response to catheterization, the student independently decided whether intramuscular ketamine was required. RESULTS: Cats in the aceFFP group appeared to be calmer than acePlac cats on the basis of head position and their location in the cage (suggesting benefit from FFP among cats receiving acepromazine) but appeared to be less sedated. Cats in the aceFFP group also appeared to be calmer than FFP cats on the basis of head position and location in the cage. Feline facial pheromone cats were also calmer than Plac cats when compared using body and leg position. Exposure to FFP did not significantly reduce struggling at catheterization, nevertheless, the students were able to catheterize the veins in all cats. CONCLUSION AND CLINICAL RELEVANCE: There were no detrimental behavioural effects associated with either FFP or acepromazine. The FFP had additional calming effects in cats given acepromazine and, to a lesser degree, helped to calm cats that were not given acepromazine. Feline facial pheromone helps to calm cats in unfamiliar surroundings.  相似文献   
4.
5.
Abstract

The relationship between the catch of male Spodoptera litura (F.) moths in sex pheromone‐baited traps and the number of egg‐masses in groundnut crop at the International Crops Research Institute for Semi‐Arid Tropics Centre Patancheru, India was examined during the post‐rainy season of 1983. Significant positive correlations were found between the number of egg‐masses and the total number of male moths caught during the 7 days preceding the egg‐mass count. 75% of the variance in the egg‐mass counts and pheromone trap catches could be accounted for by the regression.  相似文献   
6.
性诱技术是应用于果园的一种无公害、绿色防治技术。梨小食心虫是江西省梨产区的一种主要害虫,为了寻求适时有效的防治方法,于2012年,利用性诱剂迷向散发器(即迷向丝)进行了防治试验。结果表明:利用性诱剂迷向法可使98%以上的梨小食心虫迷失方向,明显减少梨小食心虫的发生数量,减少了被害果,蛀果率只有1.8%,比对照降低了13个百分点,从而增加了梨果产值,同时降低了化学杀虫剂的使用量。  相似文献   
7.
8.
Field bioassays were conducted in south-central Alaska in a stand of Lutz spruce, Picea × lutzii, to determine whether a semiochemical interruptant (verbenone and trans-conophthorin) and/or a defense-inducing plant hormone (methyl jasmonate, MJ) could be used to protect individual standing trees from bark beetle attack. During two experiments (initiated in May 2004 and 2005, respectively), attacks by Ips perturbatus on standing trees were induced by using a three-component aggregation pheromone (ipsenol, cis-verbenol, and ipsdienol) and prevented by using the interruptant. In 2005, treatments from 2004 were repeated and additional treatments were evaluated by using MJ spray or injection with and without the interruptant. Aggregation began before 3 or 7 June, and attack density was monitored through 3 or 16 August. During both years, tree mortality caused by I. perturbatus was recorded twice (in August, and in May of the following year). In both experiments, attack density was greatest on trees baited with the three-component attractive pheromone, but was significantly reduced by addition of the semiochemical interruptant to trees baited with the attractant. There were no significant differences in attack density between attractant + interruptant-treated trees and unbaited trees. In 2004, mortality was highest among attractant-baited trees, whereas addition of the interruptant significantly reduced the level of initial (10 week post-treatment) and final (54 week post-treatment) mortality. In 2005, no significant reduction in attack density occurred on trees baited with the attractant when MJ was sprayed or injected. The highest initial (10.6 week post-treatment) and final (49.4 week post-treatment) mortality was observed among trees that had been injected with MJ and baited with the attractant. Mortality at the final assessment was significantly lower in all other treatment groups. As in 2004, addition of the interruptant to attractant-baited trees significantly reduced the level of final mortality compared to attractant-baited trees. MJ was not attractive or interruptive to I. perturbatus or associated bark beetles in a flight trapping study. However, MJ-treated trees (sprayed or injected) exuded copious amounts of resin on the bark surface. Anatomical analyses of felled trees from four treatment groups [Tween (solvent)-sprayed, MJ-sprayed, Tween-injected, and MJ-injected + attractant baited] showed that treatment with MJ increased the number and size of resin ducts produced following treatment. These analyses also revealed a reduction in radial growth in MJ-treated trees. Our results show that during both years, treatment with a simple, two-component interruptant system of verbenone and trans-conophthorin significantly reduced I. perturbatus attack density and tree mortality on attractant-baited trees and provided a full year of protection from bark beetle attack.  相似文献   
9.
利用性信息素控制害虫是无公害农业生产者的一种方法,引进日本产复合搅乱剂-A的迷向法控制苹果桃小食心虫、金纹细蛾、卷叶蛾等几种主要害虫试验,无论是连续二年还是当年的处理,其危害率都较对照降低40%~90%,且复合性信息素一次处理,简便易行。引进的桃小食心虫和金纹细蛾性诱剂进行的大量诱捕防治试验,也取得一定效果,特别是诱蛾量高于国产性诱剂的诱蛾量。  相似文献   
10.
性诱剂对蔬菜大棚小菜蛾种群的控制效应   总被引:19,自引:0,他引:19  
试验表明,小菜蛾性诱剂对小菜蛾种群的控制效应明显,但以低密度卵量(1-3粒/株)的控制效应较高,可达70%左右;不同蔬菜上小菜蛾用性诱剂的控制效果差异较大,在菜心和上海青上的控制效果较高,而在芥蓝和奶白上的控制效果较小,这主要与不同蔬菜上小菜蛾种群发生动态有关;在整个菜心生育期中,以3个诱盆/180m^2大棚的平均每盆诱捕雄蛾量最高;在6造菜心上连续用小菜蛾性诱剂诱捕效果可保持在70%左右。  相似文献   
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