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1.
Commun Agric Appl Biol Sci ; 80(3): 331-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27141730

RESUMO

Behaviour modifying pheromones are well known agents for disrupting mating communication of pest insects. For optimal activity, they must be dispensed in time and space at a quantitatively measurable, predetermined release rate covering the flight period of the target species. Pheromones appeal to environmentally conscientious entomologists for their biodegradability, non-toxicity and ecological compatibility. In attempts of combining the virtues of pheromones, suitable slow release dispensers, and their mechanical deployment, an ecologically sensible, reasonably priced and patented procedure was developed and tested with the vineyard pest Lobesia botrana (Lep.: Tortricidae). It is characterized by (1) Electrospun mesofibers with diameters ranging from 0.6 to 3.5 micrometres, containing disruptants and dispensing it by slow release diffusion into the crop, (2) simultaneous application of the fully biodegradable combination of pheromone with Ecoflex polyester mesofiber, (3) combination of mechanical deployment by multi-purpose cultivators of the prefabricated pheromone dispensers with other simultaneous cultivation measures, and thus further reducing labour time and treatment costs. The dispensers are biodegradable within half a year without leaving any objectionable residues. In the standard eco-toxicology tests pheromone dispensers are harmless to non-target organisms. The disruptive effect of one treatment lasts for seven weeks which covers well one of several flight periods of L. botrana.


Assuntos
Controle de Insetos/métodos , Mariposas/fisiologia , Controle Biológico de Vetores/métodos , Feromônios/farmacologia , Doenças das Plantas/prevenção & controle , Vitis/parasitologia , Animais , Controle de Insetos/instrumentação , Mariposas/efeitos dos fármacos , Controle Biológico de Vetores/instrumentação , Doenças das Plantas/parasitologia , Comportamento Sexual Animal/efeitos dos fármacos
2.
Commun Agric Appl Biol Sci ; 80(2): 111-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27145575

RESUMO

Ergography is a novel technique invented in 2003 by the first author in his attempts to understand, analyze, and quantify at one glance the work of creative scientists without reading through lengthy, usually boring laudations of invited speakers. Traditional enumeration of accomplishments is helpful but less than satisfactory. Simple descriptive texts often do not satisfactorily answer the question of how, when and why certain observations and theories were established and how they influenced the development and advance of scientific fields at large. Five influential entomologists, R.L. Metcalf, H. Schmutterer, P. Karlson, T. Eisner and E.O. Wilson, as well as two biochemists, A. Butenandt and F. Lynen, a few of them still alive, were selected as targets to gain some experience with the new technique superficially resembling chromatograms or spectra. Pretty soon, it became clear that the "when" is easy to answer and follows from simple time diagrams. More difficult is the analysis of the "how" and "why" and "under whose influence" certain subject areas were pursued. Even more difficult to analyze is the impact, if any, certain papers had on subsequent authors and to what extent the "memes" influence contemporary or future authors within and outside established research schools of thought. Ergographic analysis is an ongoing project that learns its rules by trying and doing. It links the forefront of research to the task of the science historian who is looking back over considerable distances. Ergographists try to speed up this process by the tools of analyzing working patterns and hopefully finding similarities and signs of influences in other schools of thought. In the virtual absence of suitable critical electronic software with semantic resolution power, ergography is still a matter of personal enterprise, curiosity, intuition, and willingness to follow with a prepared mind the paths investigated before by ingenious talent and make them more transparent.


Assuntos
Bibliografias como Assunto , Bioquímica , Entomologia , Informática/métodos
3.
Commun Agric Appl Biol Sci ; 79(2): 211-28, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26084100

RESUMO

Neem plants (Rutales: Meliaceae) are well known for their multitude of human benefits in various fields. Specifically well investigated are the Indian neem tree Azadirachta indica A. Juss., the Thai neem A. siamensis Val., the originally Malaysian/Philippinean neem A. excelsa (Jack) and, as a close relative, the Persian lilac, Melia azedarach. The major and most active natural products are azadirachtin, salannin, nimbin and marrangin from Azadirachta species, and azadirachtin analogues like meliantriol from Melia species. Neem fruits, leaves, bark, and roots have specific virtues. They have been traditionally exploited for a considerable part of human history and are documented in Sanskrit texts. Due to human activity in trade and travel both at land and sea, the plant species has been distributed around the globe and is cultivated in many tropical, and subtropical regions. A multitude of natural products of neem have been isolated, chemically characterized or identified, and investigated for their properties in the management of insects, Acarina, Crustacea, nematodes, bacteria, fungi, viruses and soil fertility (for reviews see Kraus, 2002; Schmutterer, 2002A; Rembold, 2002; Koul, 2004; Schmutterer and Huber, 2005; Kleeberg and Strang, 2009; Hummel et al., 2008, 2011, 2012). Neem products are virtually nontoxic, compatible with beneficial insects, pollinators and bees. They are environmentally benign, sustainable, renewable, and of a price affordable for developed countries. In conclusion, neem is a prime example of a natural resource with many beneficial applications in agriculture, human and veterinary medicine. So far, its use is practically free of resistance problems which are frustratingly prevalent in many areas of synthetic insecticide and drug development. Investigating more neem applications will increase future human welfare and health while being of general ecological benefit to the planet.


Assuntos
Anti-Infecciosos/farmacologia , Azadirachta/química , Extratos Vegetais/farmacologia , Animais , Anti-Infecciosos/efeitos adversos , Anti-Infecciosos/química , Humanos , Inseticidas/efeitos adversos , Inseticidas/química , Inseticidas/farmacologia , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química
4.
Commun Agric Appl Biol Sci ; 79(2): 265-77, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26084106

RESUMO

"Push-Pull" is an inexpensive and eminently practical strategy designed for developing countries in order to exploit sound principles of chemical ecology for agricultural pest management. This strategy is specifically suitable for small holder farmers. Their experience can easily be integrated into existing farming practices in their immediate environment. "Push-pull" within one and a half decades became widely established and meanwhile is greatly beneficial to practitioners in East Africa, mainly Kenya. The classical push-pull approach used for applied plant-insect management was pioneered by Khan and Pickett (2000) and subsequent papers of Pickett (2003) and Khan et al. (2006, 2008). Relevant plant species explored so far were maize or sorghum intercropped with other East African plants (Desmodium spp. resp. Melinis minutiflora) possessing natural chemicals repellent resp. attractive for stem borer moths Chilo partellus (Lepidoptera), whereby Desmodium spp. was grown inside the maize rows while M. minutiflora surrounded it. Both simultaneous actions combined resulted in a significant decrease of stem borers in the area to be protected. A benefit to cost ratio of 2.5 was realized. Within a period of 15 years the number of subscribing farmers substantially increased from a few dozen to more than 80,000 in 2014. Two experiments along the paths of chemical ecology were undertaken between Sept 2012 and Feb 2013: One was designed to investigate if the legume D. intortum known to produce repellent volatiles against stem borer moths induces defence in Zea mays varieties. We looked at two open-pollinated farmers' varieties and two commercial hybrid varieties suspecting the farmers' varieties to be responsive rather than the hybrids. However, no defence induction was detected in this study so far. This could be explained by an insufficient production of defence inducing volatiles in leaves of D. intortum whereas flowers might produce a sufficient response. More detailed study is needed. A second approach made use of species-specific insect monitoring traps baited with highly specific female sex pheromones for attracting and monitoring destructive insect pests. The female sex pheromone (8-methyl-decane-2-ol propanoate) of Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) (Western Corn Rootworm) is readily available as bait in the "Metcalf sticky cup trap" for trapping males, an extraordinarily sensitive technique for monitoring the presence or absence of male beetles in a given area. Li et al. (2006) had argued for the likelihood of easy immigration of this cosmopolitan maize pest into East Africa. Our results, however, so far indicate the absence of a local population in the area of Mbita, while not excluding its presence at Nairobi or Mombasa. Both investigations contribute to different aspects of Kenyan economic development and may be seen as two independent but complementary contributions towards livelihood improvement of small holder farmers in Kenya.


Assuntos
Agricultura/métodos , Controle de Insetos/métodos , Controle Biológico de Vetores/métodos , Doenças das Plantas/prevenção & controle , Zea mays/crescimento & desenvolvimento , Animais , Besouros/efeitos dos fármacos , Besouros/fisiologia , Fabaceae/química , Fabaceae/metabolismo , Feminino , Quênia , Masculino , Mariposas/efeitos dos fármacos , Mariposas/fisiologia , Feromônios/farmacologia , Doenças das Plantas/parasitologia , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/farmacologia , Zea mays/parasitologia
5.
Commun Agric Appl Biol Sci ; 78(2): 233-52, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25145244

RESUMO

Pheromone dispensers, although known in a variety of different designs, are one of the few remaining technical bottlenecks along the way to a sustainable pheromone based strategy in integrated pest management (IPM). Mating disruption with synthetic pheromones is a viable pest management approach. Suitable pheromone dispensers for these mating disruption schemes, however, are lagging behind the general availability of pheromones. Specifically, there is a need for matching the properties of the synthetic pheromones, the release rates suitable for certain insect species, and the environmental requirements of specific crop management. The "ideal" dispenser should release pheromones at a constant but pre-adjustable rate, should be mechanically applicable, completely biodegradable and thus save the costs for recovering spent dispensers. These should be made from renewable, cheap organic material, be economically inexpensive, and be toxicologically and eco-toxicologically inert to provide satisfactory solutions for the needs of practicing growers. In favourable cases, they will be economically competitive with conventional pesticide treatments and by far superior in terms of environmental and eco-toxicological suitability. In the course of the last 40 years, mating disruption, a non-toxicological approach, provided proof for its potential in dozens of pest insects of various orders and families. Applications for IPM in many countries of the industrialized and developing world have been reported. While some dispensers have reached wide circulation, only few of the key performing parameters fit the above requirements ideally and must be approximated with some sacrifice in performance. A fair comparison of the innovation potential of currently available pheromone dispensers is attempted. The authors advance here the use of innovative electrospun organic fibers with dimensions in the "meso" (high nano- to low micrometer) region. Due to their unique multitude of adjustable parameters, they hold considerable promise for future pest control against a variety of pest insects. In combination with well known synthetic sex pheromones, they can be used for communication disruption studies. One example, the pheromone of the European grape vine moth Lobesia botrana (Lepidoptera: Tortricidae), in combination with Ecoflex fibers, has been thoroughly tested in vineyards of Freiburg, Southwest Germany, with promising results. Seven weeks of communication disruption have been achieved, long enough to cover any one of several flights of this multivoltine grape pest. Disruption effects of around 95% have been achieved which are statistically indistinguishable from positive controls tested simultaneously with Isonet LE fibers, while an untreated negative control is significantly different. Ecoflex is a cheap organic co-polyester and completely biodegradable within half a year. Thus, an extra recovery step as with some other dispensers is unnecessary. This co-polyester is also of proven non-toxicity. The extension of the seven week disruption period towards half a year (the entire duration of all 3 Lobesia flights combined) is desirable and is under additional investigation in the near future. The discovery of suitable mesofibers is protected by European and US patents. The pheromone literature appearing between 1959 and today contains more than 25,000 references. This wealth of information is immediately applicable to pest management. It has major impacts on chemical ecology and IPM. In this paper, an attempt is made to compare the systems described in the literature and to derive some predictions about their prospective innovation potential. Special emphasis is given to the new development of organic biodegradable microfibers. To this end, a new electronic searching algorithm is introduced for reviewing the entries to be found in 4 specific databases. Its prominent features will be described. Surprisingly we found no previous entries in the literature linking pheromones with biodegradable organic polymer fibers whose diameters are in the dimension range of low micrometers and in the upper nanometer scale. In conclusion, the microfiber-pheromone combination must be considered as a novel approach whose virtues should be further explored for IPM in the near future.


Assuntos
Controle de Insetos/métodos , Insetos/efeitos dos fármacos , Controle Biológico de Vetores/métodos , Feromônios/farmacologia , Doenças das Plantas/prevenção & controle , Animais , Produtos Agrícolas/parasitologia , Bases de Dados Factuais , Feminino , Controle de Insetos/instrumentação , Insetos/fisiologia , Masculino , Controle Biológico de Vetores/instrumentação , Doenças das Plantas/parasitologia , Comportamento Sexual Animal
6.
Commun Agric Appl Biol Sci ; 78(2): 253-66, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25145245

RESUMO

Modern insect pest management is faced with an increasingly sophisticated set of requirements. Control agent/dispenser combinations must be at the same time safe, nontoxic, inexpensive, reproducibly efficacious, environmentally compatible, biodegradable, and sustainable, and should be based on renewable resources. The methods employed preferably should be suitable for the growing and tightly controlled organic growing sector as well. All this calls for a level of sophistication and reproducibility previously unknown. Only very few systems can offer this kind of performance, but fortunately can be found in the area of suitable pheromone/dispenser combinations. This report is an attempt to adapt electrospun Ecoflex polyester micro fibers of the Greiner-Wendorff type to the very specific needs of the grape growing industry. Specifically required are "semi-intelligent" dispenser materials. On a weight basis, the electrospun product should achieve as high a proportion as possible of "retainable" sex pheromone (E,Z)-7,9-dodecadienyl acetate of Lobesia botrana (Lep.: Tortricidae) and should release it as uniformly as possible into the surrounding airspace. Using the Doye bioassay, some progress indeed has recently been achieved with electrospun Ecoflex microfibers of 0.5-3.5 microm diameter. They were employed as dispensers for programmed sex pheromone release with an effective mating disruption duration of up to seven weeks. With one microfiber/pheromone treatment, this covers one entire flight period of the trivoltine L. botrana. Mechanical application of this microfiber/pheromone preparation (with the option of automation) is possible. Disruption effects are comparable with those of commercially available dispensers of the Isonet type. Exposed under vineyard conditions, Ecoflex polyester fibers are a spider silk like material which is biodegradable within half a year. Thus, after releasing its pheromone load, it does not need removal, which saves one cultivation step. The fibers are under rigorous quantitative pretesting by analytical lab methods such as scanning EM, CLSA, timed weight loss curves in isothermal wind tunnels, and by thermogravimetry. Grapes produced under protection with these pheromone-charged biodegradable and mechanically deployable Ecoflex microfibers are completely free of pesticide residues.


Assuntos
Dodecanol/análogos & derivados , Mariposas/efeitos dos fármacos , Controle Biológico de Vetores/instrumentação , Controle Biológico de Vetores/métodos , Doenças das Plantas/prevenção & controle , Poliésteres/química , Atrativos Sexuais/farmacologia , Vitis/parasitologia , Animais , Biodegradação Ambiental , Dodecanol/química , Dodecanol/farmacologia , Feminino , Controle de Insetos/instrumentação , Controle de Insetos/métodos , Cinética , Masculino , Mariposas/fisiologia , Doenças das Plantas/parasitologia , Poliésteres/síntese química , Atrativos Sexuais/química , Comportamento Sexual Animal/efeitos dos fármacos
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