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1.
Pablo Bielza Virginia Balanza Dina Cifuentes Jos E Mendoza 《Pest management science》2020,76(11):3517-3526
Biological control is an efficient pest control method but there are still limitations that are hindering its wider adoption. Genetic improvement of biological control agents (BCAs) can help to overcome these constraints, but the choice of key attributes for better performance that need to be selected is still an open question. Several characteristics have been suggested but the harsh reality is that selective breeding of BCAs has received a lot of attention but resulted in very little progress. Identifying the appropriate traits to be prioritized may be the first step to reverse this situation. In our opinion, the best way is to look at the factors limiting the performance of key BCAs, especially generalist predators (pesticide compatibility, prey‐density dependence, non‐suitable crops, and extreme environmental conditions), and according to these challenges, to choose the attributes that would allow BCAs to overcome those limitations. The benefits of selection for higher resistance to toxins, whether artificially applied (pesticides) or plant produced (plant defenses); increased fitness when feeding on non‐prey food (supplemented or plant‐derived); and better adaptation to extreme temperature and humidity are discussed. In conclusion, genetic improvement of BCAs can bring about new opportunities to biocontrol industry and users to enhance biocontrol resilience. © 2020 Society of Chemical Industry 相似文献
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Quantitative data were obtained for arboreal species within 50 lowland forests in southeastern Ohio. Thirty-seven communities were dominated by Betula nigra L. and 13 were dominated by Acer saccharinum L. The acidic soils collected from B. nigra communities contained toxic concentrations of exchangeable Al and low concentrations of Ca and Mg. Tree species diversity (Shannon-Weaver index) and species equitability were inversely related to high concentrations of exchangeable Al and H and directly related to high concentrations of exchangeable Ca and Mg and an increase in soil pH. 相似文献
4.
鸡粪生物炭表征及其对水和土壤镉铅的修复效果 总被引:8,自引:4,他引:4
采用缺氧控温法,在200、400、600和800℃条件下制备鸡粪生物炭(BC200、BC400、BC600和BC800),利用比表面积及孔径分析仪(BETacceleratedsurfaceareaandporosimetrysystem)、扫描电镜(scanningelectron microscopy)、透射电镜(transmission electron microscope)、傅里叶红外光谱仪(Fourier transform infrared spectroscopy)等对其理化性质和结构特征进行表征,并研究了鸡粪不同温度处理下生物炭对水体和土壤中Cd、Pb污染修复效果。结果表明,鸡粪生物炭灰分含量、pH值、BET比表面积及孔径随热解温度的升高而增加,表面出现大量无规则的孔隙结构,且以介孔为主,而生物炭产率则随温度升高而显著降低(P0.05)。鸡粪生物炭对Cd2+、Pb2+的吸附分为快速吸附和慢吸附2个阶段,Elovich模型能更好地模拟Pb2+、Cd2+的动力学过程,平衡时最大吸附量分别达到52.02 mg/g (BC600)和242.59 mg/g (BC800)。添加鸡粪生物炭显著提高了土壤pH值(P0.05),而TCLP提取态Pb、Cd含量降低,最大较对照分别降低16.5%和14.5%。与对照相比,鸡粪生物炭不同程度上降低了Pb、Cd弱酸提取态、可还原态以及可氧化态比例,其残渣态比例则分别增加了5.49%~15.14%和2.51%~6.30%。综上所述,鸡粪生物炭对重金属Pb、Cd具有较强的钝化效果。 相似文献
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Objective— To evaluate combined bilateral thyroarytenoid cartilage lateralization, vocal fold excision, and mucosoplasty technique (BTAL) through ventral median laryngotomy for treatment of laryngeal paralysis in dogs.
Design— Retrospective study.
Animals— Dogs (n=67) with laryngeal paralysis.
Methods— Medical records were reviewed for dogs with idiopathic laryngeal paralysis that had BTAL between January 1998 and March 2005. Retrieved data included signalment, history, physical and laryngoscopic examination findings, clinicopathologic tests, and results of recheck examination findings.
Results— BTAL was performed by a single surgeon. Short-term (<6 months) follow-up information was available for 67 dogs and long-term (>12 months) for 40 dogs. Major postoperative complications were surgical failures (13; 7 short term, 6 long term) and aspiration pneumonia (1). Mean recurrence of clinical signs was at 19 weeks (range, 2–30 weeks). Minor complications occurred in 22 (33%) dogs including occasional coughing or gagging, stridorous breathing during exercise, panting, noisy or heavy breathing, and aspiration pneumonia (3 dogs) that did not require hospitalization. All owners reported an improved quality of life and had no regrets with surgical outcome.
Conclusions— BTAL is seemingly an effective procedure for treatment of laryngeal paralysis.
Clinical Relevance— BTAL is associated with a low incidence of aspiration pneumonia; however, there is substantial risk of recurrence of clinical signs associated with narrowing of the glottis. Consequently, unilateral arytenoid lateralization currently represents the accepted approach to the treatment of laryngeal paralysis. 相似文献
Design— Retrospective study.
Animals— Dogs (n=67) with laryngeal paralysis.
Methods— Medical records were reviewed for dogs with idiopathic laryngeal paralysis that had BTAL between January 1998 and March 2005. Retrieved data included signalment, history, physical and laryngoscopic examination findings, clinicopathologic tests, and results of recheck examination findings.
Results— BTAL was performed by a single surgeon. Short-term (<6 months) follow-up information was available for 67 dogs and long-term (>12 months) for 40 dogs. Major postoperative complications were surgical failures (13; 7 short term, 6 long term) and aspiration pneumonia (1). Mean recurrence of clinical signs was at 19 weeks (range, 2–30 weeks). Minor complications occurred in 22 (33%) dogs including occasional coughing or gagging, stridorous breathing during exercise, panting, noisy or heavy breathing, and aspiration pneumonia (3 dogs) that did not require hospitalization. All owners reported an improved quality of life and had no regrets with surgical outcome.
Conclusions— BTAL is seemingly an effective procedure for treatment of laryngeal paralysis.
Clinical Relevance— BTAL is associated with a low incidence of aspiration pneumonia; however, there is substantial risk of recurrence of clinical signs associated with narrowing of the glottis. Consequently, unilateral arytenoid lateralization currently represents the accepted approach to the treatment of laryngeal paralysis. 相似文献
6.
Anurag Dagar Dina Zilberg Zvi Cohen Sammy Boussiba & Inna Khozin-Goldberg 《Aquaculture Research》2010,41(2):267-277
Two trials were conducted to determine the effects of dietary enrichments with the microalga Parietochloris incisa , rich in arachidonic acid (ARA), on stress resistance in guppies Poecilia reticulata . The microalga was added to commercial diets as a neutral lipid (NL) extract and its fractions or as broken cells. Experimental diets were applied for a period of 14 days. In trial 1, commercial diets were supplemented with NL (containing 25 mg ARA and 0.11 mg β-carotene g−1 feed), its triacylglycerol (TAG) fraction (containing 25 mg ARA g−1 feed and no β-carotene) and the β-carotene fraction (containing 0.11 mg carotenoid g−1 feed and minute amounts of ARA). Neutral lipid-fed fish demonstrated the highest resistance ( P <0.05) to osmotic stress (32-ppt NaCl), followed by fish fed with diets supplemented with TAG and β-carotene alone, which were more resistant than control ( P <0.05). In trial 2, fish fed diets supplemented with higher levels of broken alga (26.1 mg ARA g−1 feed) were more resistant ( P <0.05) to stress as compared with fish fed lower ARA (16.3 mg g g−1 ) or an unsupplemented control diet. We suggest a dietary supplementation with broken P. incisa cells to enhance stress resistance in guppies before a stressful event. 相似文献
7.
Ji Hyun Kim Sophie Fridman Hamutal Borochov‐Neori Tamar Sinai Dina Zilberg 《Aquaculture Research》2019,50(2):431-438
Garlic (Allium sativum) has been shown to possess antimicrobial properties against a range of disease‐causing agents, including fish parasites. Our study aimed to investigate the potential use of garlic as a treatment against Cryptocaryon irritans infection, using guppies (Poecilia reticulata) as the fish model. Garlic was freeze‐dried, powdered, and used as it is or as an aqueous extract. The content of allicin, its main active ingredient, was 1.25 mg/g in garlic powder and 0.82 mg/ml in the aqueous extract, as determined by HPLC analysis. Aqueous garlic extract fully immobilized C. irritans theronts and protomonts within 20 and 40 min, respectively, following exposure to 5 µl/ml. Treatment trials were performed, in which infected fish were fed with garlic powder‐supplemented feeds (5%, 10%, or 20% supplementation), bathed in garlic aqueous extract (250 or 500 µl/L) and subjected to a combined treatment which included both feeding and bathing. Results revealed that the tested treatments failed to cure the infection, though reduction in infection intensity on the caudal fin, but not on the gills, was evident following dietary supplementation with 20% of powdered garlic in one of the trials. 相似文献
8.
黄淮海地区商品鸡饲料中重金属含量特征研究 总被引:1,自引:0,他引:1
为了从源头有效控制家禽养殖重金属污染,本文调查了黄淮海地区(北京、天津、河南、河北、山东、江苏、安徽)180个商品鸡饲料样品,分析了不同省市、不同养殖品种和不同生育期饲料中Mn、Cu、Zn、Cr、Ni、Cd、Pb和As 8种重金属含量特征。结果表明:黄淮海地区鸡饲料中重金属含量变化幅度较大,饲料样品中Cr、Mn、Ni、Cu、Zn、As、Cd和Pb含量范围分别为0.05~9.91、52.59~726.68、0.02~6.84、12.74~458.70、34.09~594.78、0.01~3.98、0.01~1.96 mg·kg-1和0.02~10.76 mg·kg-1,与我国《鸡饲养标准》(NY/T 33—2004)含量相比,饲料样品Mn、Cu、Zn超标率分别为99.1%、100%、69.0%,与《饲料卫生标准》(GB 13078—2001)含量相比,饲料样品中Pb、Cd含量超标率为39.7%、23.50%。不同省市鸡饲料中重金属的含量存在一定差异,总体上来看,安徽省鸡饲料中重金属含量最高,天津市鸡饲料中含量最低。蛋鸡Mn、Cu、Zn含量最大检出量分别为680.86、458.70、580.27 mg·kg-1,肉鸡Mn、Cu、Zn含量最大检出量分别达到726.68、399.07、594.78 mg·kg-1,蛋鸡和肉鸡饲料中Mn、Cu、Zn平均含量均超过我国《鸡饲养标准》。总体来看,产蛋期蛋鸡饲料中重金属含量最高,中后期肉鸡饲料中重金属含量较高。 相似文献
9.
Vishnu D. Rajput Tatiana Minkina Svetlana Sushkova Viktoriia Tsitsuashvili Saglara Mandzhieva Andrey Gorovtsov Dina Nevidomskyaya Natalya Gromakova 《Journal of Soils and Sediments》2018,18(6):2179-2187
Purpose
Nanoparticles (NPs) have received increased attention in recent past due to their unique distinct properties. Metal-based NPs are widely used in chemical and allied sector. Most of the research is directed to study the efficiency of NPs in medicine and agriculture. The aim of this review is to explore the possible threats posed by toxicity of various NPs on plants and microbial diversity.Materials and methods
First, major sources of NPs to the environment were analyzed. The effects of metal-based NPs on the microbiota and plants are presented in this review. The results obtained by the authors during last 12 years of research are used.Results and discussion
The exposure of soil to nanoparticles causes a decrease in soil microbial biomass and enzymatic activity, which impacts microbial community composition including yeasts, bacteria, fungi, and biological diversity. The effects of NPs on plants result in various types of abnormalities. Nanoparticles can also pose risks to human health.Conclusions
Increased applications of NPs pose a threat to beneficial microbial communities as well as crops and soils. Thus, it is important to explore whether NPs could compromise crop yield, soil properties, soil organisms, and functional activities of soil.10.
Mandzhieva Saglara S. Minkina Tatiana M. Chaplygin Victor A. Motuzova Galina V. Sushkova Svetlana N. Bauer Tatiana V. Nevidomskaya Dina G. 《Journal of Soils and Sediments》2016,16(4):1383-1391
Journal of Soils and Sediments - The aim of this study is the assessment of Ni, Mn, Cd, Cu, Pb, Cr and Zn accumulation by different herbaceous species and soils on the technogenic areas around... 相似文献