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1.
为了明确谷胱甘肽S-转移酶（glutathion S-transferases, GSTs）基因与柑橘全爪螨抗性的关系,通过BLAST搜索,对柑橘全爪螨转录组数据库的GST基因进行鉴定,应用MEGA4.0.1软件对GST基因进行同源与进化分析,进一步采用RPKM法对柑橘全爪螨敏感品系和噻螨酮抗性品系GST基因进行表达差异分析。从柑橘全爪螨转录组中获得了30条GST基因,其中11条基因属于Delta家族,10条属于Mu家族,2条属于Omega家族,6条属于Kappa家族,1条属于Zeta家族。基因表达差异分析发现,抗性与敏感品系当中有25条GST基因表达量存在差异,抗性品系中有9条GST基因发生了上调,16条发生了下调,其中上调倍数最高的是GSTd6[log2 Ratio(RS/SS)= 1.0505],由此推断,GST基因的上调可能不是柑橘全爪螨对噻螨酮产生抗性的重要原因。 相似文献
2.
柑橘全爪螨(Panonychus citri McGregor)是柑橘上的重要害虫,目前主要通过化学药剂对其进行防治,但由于长期以来化学药剂的不合理使用使得其对不同杀螨剂产生了不同程度的抗性。通过对监测数据的分析能够更好的指导田间用药,为实际生产中柑橘全爪螨的防治与其抗药性治理提供理论依据。2021年采用叶碟浸渍法对广西桂林临桂区和灵川县两个柑橘全爪螨田间种群进行了抗药性测定。结果标明：桂林临桂、灵川两地柑橘全爪螨田间种群对乙唑螨腈、联苯肼酯、阿维菌素和乙螨唑均已产生高水平抗性(105.6-572.0倍);且对哒螨灵和螺螨酯也产生了中等水平抗性(44.8-96.2倍)。生产上应减少阿维菌素、联苯肼酯和乙螨唑的使用,应合理的进行复配,并结合其他防治措施进行综合防治,保障我国柑橘产量与品质。 相似文献
3.
杀虫剂螨危的亚致死剂量对朱砂叶螨种群参数的影响 总被引：1，自引：1，他引：0
朱砂叶螨是桑树的主要害虫之一。从避免过度使用农药造成环境污染和控制害螨的抗性发展的角度,研究了杀虫剂螨危的亚致死剂量对朱砂叶螨敏感种群生存与繁殖能力的影响。分别用质量浓度为1.25、2.5、5、10、40 mg/L的螨危药液处理雌成螨,48 h后的存活率分别为96%、83%、81%、75%、48%;药液对雌成螨和卵的致死中浓度(LC50)分别是35.005 mg/L和0.690 mg/L,卵的敏感性明显高于雌成螨。与对照组相比,随螨危药液处理浓度增高,雌成螨的7 d总产卵量和孵化率呈下降趋势;用10、5、2.5、1.25 mg/L药液处理后朱砂叶螨种群的瞬时增长率(ri)分别是-0.083、0.142、0.214、0.298,而对照组为0.544,有效中浓度(EC50)值为1.627 mg/L。研究结果表明,用低于推荐使用浓度(40 mg/L)的螨危药液就能有效控制朱砂叶螨种群的增长。 相似文献
4.
不同温度下苜蓿叶象甲实验种群生命表研究 总被引：1，自引：0，他引：1
为了研究温度对苜蓿叶象甲(Hypera postica Gyllenhal)种群动态的影响,组建了其在18℃,22℃,26℃,30℃下的实验种群生命表。结果表明:18~30℃范围内,苜蓿叶象甲发育速率随温度的升高而加快,并符合Logistic模型。苜蓿叶象甲的卵、幼虫、前蛹、蛹及产卵前期成虫的发育起点温度分别为8.82,10.47,8.60,11.91和9.53℃,有效积温分别为99.38,143.80,48.63,55.71和140.15℃·d,完成整个世代需要的有效积温为480.96℃·d。实验温度条件下其生存曲线呈A型,26℃时世代存活率及单雌产卵量最高,分别为47.6%,847.7粒。苜蓿叶象甲世代存活率(S)、种群趋势指数(I)与温度(t)间均呈抛物线关系,其生长发育繁殖的最适温区为25~27℃。 相似文献
5.
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
6.
为了解近期桂林地区柑橘全爪螨抗药性发展情况,本文采用浸叶法调查了柑橘全爪螨对几种杀螨剂的抗药性,结果表明,对尼索朗,柑橘全爪螨卵抗性倍数为中抗水平,若螨抗性为低抗水平,雌成螨敏感性降低水平;对四螨嗪,柑橘全爪螨卵、若螨、雌成螨均处于低抗水平;对阿维菌素,柑橘全爪螨卵为低抗水平阶段,若螨和雌成螨处于敏感性降低水平;对克螨特和乙螨唑,柑橘全爪螨卵、若螨、雌成螨均没有产生抗性。由于尼索朗、四螨嗪、乙螨唑同属螨虫生长抑制剂,而尼索朗和四螨嗪已出现抗性,可以考虑乙螨唑-阿维菌素-克螨特轮换使用。 相似文献
7.
运用为害指数法,对宁夏地区主栽的26个苜蓿品种进行了室内蓟马抗性评价试验。田间蓟马种类以牛角花齿蓟马(Odontothrips loti)为主,占混合种群数量的75%,室内试虫群体结构与大田相仿。结果表明:供试26个苜蓿品种中,先行者、甘农9号、WL298HQ、耐盐之星、三得利5个品种的为害指数小于25.00%,对蓟马表现出较强的抗性;而皇后、盐宝、阿迪娜、WL354HQ 4个品种为害指数大于40.00%,对蓟马表现出较弱的抗性。同时从株高、分枝数及干草产量等方面对不同苜蓿品种抗性进行了初步研究。试验表明,蓟马为害后,抗性较强的苜蓿品种其株高绝对增长率、分枝相对增长率及干草产量损失率均高于抗性较弱的苜蓿品种。 相似文献
8.
酢浆草岩螨是为害红花酢浆草最为严重的害螨,哒螨灵作为一类广谱、触杀性杀螨剂可高效防治该害螨。为明确哒螨灵对酢浆草岩螨的亚致死效应,为酢浆草岩螨综合防控和哒螨灵的合理使用提供理论依据,采用叶片浸渍法测定哒螨灵对酢浆草岩螨的毒力,通过毒力回归方程得出哒螨灵对酢浆草岩螨的亚致死剂量LC10、LC20,采用建立生命表的方法评估哒螨灵亚致死剂量对酢浆草岩螨生长发育、繁殖力和生命表参数的影响。结果表明,经哒螨灵亚致死剂量LC10、LC20处理后,酢浆草岩螨生殖力显著下降(P<0.05),F0和F1代单雌产卵量分别下降了53.37%、55.46%与41.34%、45.24%;产卵期显著缩短(P<0.05),F0和F1代产卵期分别缩短了3.11、4.75 d与3.47、2.81 d;成螨寿命也显著缩短(P<0.05),F0和F1代成螨寿命分别缩短了1.45、2.04 d与3.24、4.00 d。此外,经哒螨灵LC10、LC20处理后,酢浆草岩螨F1代净增殖率(R0)、内禀增长率(rm)、周限增长率(λ)与对照相比均显著下降(R0由对照的28.54分别降低至16.91、15.48;rm由对照的0.1650分别降低至0.1276、0.1249;λ由对照的1.1794分别降低至1.1435、1.1330;P<0.05),平均世代历期(T)、种群加倍时间(Dt)均显著延长(T由对照的20.31 d分别延长至22.17、21.94 d;Dt由对照的4.20 d分别延长至5.43、5.55 d;P<0.05)。由此可见,哒螨灵亚致死剂量对酢浆草岩螨试验种群的增长有抑制作用。 相似文献
9.
在温度(28±1)℃、相对湿度75%±10%、光照16 L∶8 D条件下,应用生命表技术研究了朱砂叶螨在4个桑树品种上的种群生命表参数。结果表明,种群生命表的内禀增长率、净增殖率、周限增长率和种群倍增时间等参数在4个桑树品种上都存在显著差异,其中朱砂叶螨在湖桑32号和摘桑13号的内禀增长率分别为0.386 0±0.002 7和0.385 3±0.003 4,显著高于在新疆白桑(0.350 9±0.003 6)和瓜瓢桑(0.348 2±0.006 4)的内禀增长率,表明新疆白桑和瓜瓢桑对朱砂叶螨的抗性较强。研究结果对桑树抗虫品种筛选和害虫的综合防治具有一定的指导意义。 相似文献
10.
11.
The reproductive fitness of Rhipicephalus (Boophilus) microplus (Canestrini) strains resistant to organophosphate (OP), pyrethroid (P), or formamidine (F) acaricides was compared to an acaricide-susceptible (SUS) strain to determine whether the acquisition of resistance affected reproductive fitness in the resistant strains. The SUS strain females had a 3.0 days preoviposition period, a 12.1 days oviposition period, a 22.5 days egg incubation period, a mean of 3670 eggs per female, and a mean percentage egg hatch of 78.1%, which were all remarkably similar to these same parameters reported for this species throughout the world. The reproductive biology of the P-resistant strain (PYR) and the F-resistant strain (FOR) were, for the most part, similar to those of the SUS strain. In the few instances where statistical differences did occur there was little evidence that the variation had any biological basis that could be attributed to a reduction in fitness related to resistance to P or F acaricides. Although the comparison of reproductive parameters of the OP-resistant strain (OPR) and the SUS strain identified statistical differences between the mean egg incubation and oviposition periods, the magnitude of the differences was not sufficient to conclude that the OPR strain was biologically less fit than the SUS strain. However, the OPR strain produced 30% fewer eggs (2562 eggs per female) than the SUS strain (3670 eggs per female) indicating the acquisition of resistance placed the OPR at a selective disadvantage relative to the SUS strain. This coupled with a lower, though non-significant, egg hatch was used to predict there would be a reduction of at least 34.1% in larval numbers available to potentially re-infest subsequent cattle than were available from the SUS strain. These data may aid the development of management strategies that can be used to control OP-resistant ticks. 相似文献
12.
The life cycle of Rhipicephalus bursa Canestrini and Fanzago, 1877 (Acarina: ixodidae) under laboratory conditions 总被引：1，自引：0，他引：1
The biology of Rhipicephalus bursa has not been thoroughly studied. In the present study R. bursa was bred in the laboratory and its biology worked out.Larvae, nymphs and adult Rhipicephalus bursa ticks were fed on sheep and were held at 28+/-1 degrees C and 89+/-1% relative humidity (RH) in a darkened incubator. The average weight of engorged females was 0.676g (range 0.353-1.128). The average weight of eggs laid by females was 0.344g (range 0.146-0. 554g). The average number of eggs laid was 7527 (range 6263-8860) and this was significantly correlated with the weight of the females. The index of Reproduction Efficiency (number of eggs per g weight of female) was 8469.6. The index of Conversion Efficiency (weight of eggs per weight of female) was 0.5037.Peak daily oviposition, at an average of 840 eggs per female, occurred on the 6th day of oviposition. After Day 6, the rate declined steadily. The average duration of the preoviposition period was 5.1 days (range 4-7 days). The oviposition period averaged 16.5 days (range 12-21 days), and was significantly related to both the weight of the female and the number of eggs laid. The average pre-hatching period was 31.2 days (range 24-45 days). The average feeding time of larvae and nymphs of this two host tick was 15.2 days (range 14-18 days). Female ticks fed for 5.9 days on the average.Heavier nymphs produced females and a shorter premoult period was noted for lighter male nymphs. The males/females ratio was 1.38:1. The time taken to complete the life cycle was on average 142.45 days (range 99-254 days). 相似文献
13.
Efficacy of moxidectin against an ivermectin-resistant strain of Haemonchus contortus in sheep. 总被引：2，自引：0，他引：2
The efficacy of moxidectin was determined against ivermectin-susceptible and resistant strains of Haemonchus contortus. At the onset of the trial, 40 lambs were each infected with 5000 third stage larvae of one of two strains of Haemonchus contortus. The lambs were randomly sorted into eight treatment groups 28 days post-infection and were treated as follows: Group 1, susceptible strain with no treatment; Group 2, resistant strain with no treatment; Group 3, susceptible strain treated with 0.2 mg moxidectin kg-1 body weight; Group 4, resistant strain treated with 0.2 mg moxidectin kg-1; Group 5, resistant strain treated with 0.4 mg moxidectin kg-1; Group 6, susceptible strain treated with 0.2 mg ivermectin kg-1; Group 7, resistant strain treated with 0.4 mg ivermectin kg-1; Group 8, resistant strain treated with 0.8 mg ivermectin kg-1. The lambs were killed 1 week post-treatment. Comparisons were made among groups based on the number of eggs per gram of feces on the day of treatment and the numbers of worms recovered from each lamb. Both moxidectin and ivermectin were effective in removing susceptible Haemonchus with efficacies of 100% and 99.7%, respectively. The efficacy of moxidectin against the resistant strain was 99.9% and 100% at 0.2 mg kg-1 and 0.4 mg kg-1, respectively, whereas there were only 38.8% and 53.1% efficacies in the lambs treated with 0.4 mg ivermectin kg-1 and 0.8 mg kg-1 body weight, respectively. 相似文献
14.
The effect of the temperature on the transovarial passage of Babesia bigemina has been studied in female Boophilus annulatus during their oviposition. Kinetes of Babesia were present in eggs laid at the temperatures of 16, 20, 26, 28, 30 and 35 degrees C. The rate of infection was temperature dependent. It reached at least 50%, even at low temperatures. The average infection level at 26 and 30 degrees C was 270 kinetes per egg. However, between 20 and 35 degrees C the eggs laid during the first 3 days were parasite free. At 16 degrees C, no kinetes were detected during the first 13 days of oviposition. 相似文献
15.
I.E. Pérez-González M.G. Prado-Ochoa M.A. Muñoz-Guzmán V.H. Vázquez-Valadez A.M. Velázquez-Sánchez B.L. Avila-Suárez C. Cuenca-Verde E. Angeles F. Alba-Hurtado 《Veterinary parasitology》2014,199(3-4):235-241
The effects of six new synthetic carbamates on fully engorged females of four Rhipicephalus microplus strains (one reference strain susceptible to conventional ixodicides, two strains multiresistant to ixodicides and one tick field isolate) were compared. In addition, the effect of two other new synthetic carbamates was tested on larvae from the same strains. The first six tested carbamates reduced egg laying and inhibited egg hatching in the four studied strains (P < 0.05). Compared with untreated females, the eggs produced by the treated engorged female ticks of all strains had a dark, dry, opaque appearance and were less adherent. The remaining two tested carbamates induced larval mortality in all of the evaluated strains. The three studied R. microplus strains displayed 50% resistance ratios (RR50) of less than 2 when compared to the susceptible reference strain. These results demonstrate that both carbamates with a larvicidal effect and carbamates that inhibit egg laying and embryo development are efficacious against tick strains that are resistant to commercial ixodicides, no cross resistance was observed. 相似文献
16.
Two groups of six lambs were infected either with an anthelmintic-susceptible strain of Haemonchus contortus or with a strain resistant to benzimidazoles, ivermectin and salicylanilides. The pathogenicity of the two strains of parasite was compared by monitoring the development of anaemia, changes in plasma proteins and abomasal damage in the two groups of lambs. There were no significant differences between the groups, suggesting that the development of resistance to several anthelmintics did not correlate with an increase in the pathogenicity of the parasites. Furthermore, the establishment rates and egg production of the susceptible and resistant parasites were similar. However, fewer of the eggs of the resistant parasites survived and developed at a variety of temperatures. 相似文献
17.
催产素对家蚕产卵性能的影响 总被引：1，自引：0，他引：1
本试验以中国系统种夏芳为材料,用医用催产素对雌蛹、母蛾进行喷雾法和雌蛹瞬时浸渍法处理。调查了母蛾产卵速度、产卵数、产出卵率及不受精卵率,探讨了催产素对母蛾产卵的作用效果。结果表明催产素处理雌蛹或母蛾对产出卵率有降低的趋势,对不受精卵率影响不显著,但能显著提高产卵速度。 相似文献
18.
Szabó MP Mangold AJ João CF Bechara GH Guglielmone AA 《Veterinary parasitology》2005,130(1-2):131-140
In this work, the biology, mitochondrial DNA and fertility of hybrids from two strains of Rhipicephalus sanguineus, from Brazil and Argentina, were compared. Engorged larvae, nymphs and adults from Argentina weighed more and the engorgement period of adult females was significantly longer than those of their Brazilian counterparts, whereas adult female tick yield rate was higher for the Brazilian strain. High intraspecific divergence of mitochondrial DNA was detected between R. sanguineus from Brazil and Argentina. On the other hand, a strong genetic relationship was detected between European and Argentinean R. sanguineus populations while the Brazilian population appeared to be related to the African Rhipicephalus turanicus. Adult hybrid females laid eggs, which were mostly unviable, whereas a mean of more than 1400 larvae hatched per egg mass from pure Brazilian and Argentinean strains. These results showed that differences between these strains are greater than previously assumed and that the biosystematic status of R. sanguineus ticks from South America should be re-evaluated. Wide variations, such as these might account for the reported worldwide differences in biology and vector capacity of this species. 相似文献
19.
The susceptibility of 495 strains of bacteria, recently isolated in France from cows with clinical mastitis, to 10 antimicrobial agents--penicillin G, cloxacillin, oxacillin, cephalexin, cefazolin, cephapirin, cefquinome, neomycin, ampicillin and colistin--was determined by measuring their minimum inhibitory concentrations (MICS). Overall, the levels of resistance were very low except for staphylococci and penicillin G. The 167 streptococcal strains were susceptible to all of the beta-lactams tested, but six (3-6 per cent) were highly resistant to neomycin. Of the 171 staphylococcal isolates, 36.2 per cent were resistant to penicillin G, one strain of Staphylococcus sciuri was classified as methicillin-resistant, but they were all susceptible to neomycin. None of the 122 strains of Escherichia coli was resistant to colistin, but 12 had high MIC values for one or more of the cephalosporins. 相似文献
20.
1. A study was conducted to evaluate how body weight and age of each female are related to the number and physical and chemical characteristics of the eggs produced throughout a breeding season in a captive-bred population of Greater Rheas (Rhea americana). 2. Reproductive performance of 15 females of three age classes (5 individuals per class) was monitored; female body weight was recorded before laying-onset. All the eggs laid were collected and identified, and different morphometric variables, percentage of components and fatty acid composition were determined. 3. The earlier the female started egg-laying, the longer the laying period and the greater the overall number of eggs produced. The onset of egg-laying in turn seemed to be related to the attainment of a high body weight. 4. Except for length, the values of the morphometric variables of the egg and unsaturated fatty acids (palmitoleic, oleic and linoleic) increased with female age. 5. High body weight was associated with low palmitic and palmitoleic fatty acids and high linoleic, linolenic and total unsaturated fatty acids. 6. Live weight and age of females can determine several physical and chemical characteristics of eggs. 相似文献