Public land management agencies, conservation organizations, and landowners are interested in expanding the diversity of plant species used in rangeland restoration seedings. While the restoration of native grasses and shrubs in the Great Basin has become increasingly successful, restoration of native forbs continues to be problematic. In the Great Basin, soil water availability and soil fungal pathogens are thought to limit to restoration success. During the course of two years, we conducted two field experiments at three sites in the Great Basin that spanned a latitudinal gradient encompassing different precipitation and temperature patterns. In the first experiment, we evaluated two treatments for enhancing native forb restoration – snow fences and N-sulate fabric. In addition, we tested whether multiple fungicide and hydrophobic seed coatings could reduce seed and seedling mortality from soil fungal pathogens. To quantify the effectiveness of treatments, we tracked the fate of sown seeds over four life stages: germination, seedling emergence, establishment, and second-year survival. We found that snow fences and N-sulate fabric had varying degrees of success for increasing seedling emergence or establishment but ultimately did not increase second-year survival. Seed coatings increased seedling emergence but did not increase establishment or second-year survival. In the second experiment, we replicated the first experiment and also measured soil water availability to better understand how snow fences and N-sulate fabric alter soil water availability, and if differences in soil water availability can explain restoration outcomes. While we found that our treatments can increase soil water availability, increased soil water did not consistently result in better restoration outcomes. Snow fences did not benefit any life stage at any site while N-sulate fabric had positive and negative effects on forb restoration depending on the site. Seed coatings increased seedling emergence and establishment at all sites, warranting further research with other forb species. Results from both experiments provide insights for developing new treatments and techniques that can improve native forb restoration in the Great Basin and similar semiarid systems.

Krankheiten und Schädlinge im Zierpflanzenbau. Hinweise zur Bekämpfung. Übersicht und Einsatzmöglichkeiten der zugelassenen Pflanzenschutzmittel

Die Broschüre gibt anwendungsorientierte Informationen zum Pflanzenschutz im Zierpflanzenbau, sie beinhaltet Empfehlungen zu chemischen und biologischen Bekämpfungsmöglichkeiten. Zum Einsatz von Nutzorganismen werden detaillierte Einsatzmöglichkeiten in ausgewählten Kulturen aufgezeigt.

Die aktuelle Ausgabe der Broschüre gibt anwendungsorientierte Informationen zum Pflanzenschutz. Sie beinhaltet Empfehlungen sowohl zu chemischen als auch biologischen Bekämpfungsmöglichkeiten. Es werden wesentliche Rechtsgrundlagen der Pflanzenschutzmittelanwendung genannt sowie Hinweise zur Kontrolle und Reinigung von Pflanzenschutzgeräten gegeben.

Phan Me is a midland-mountainous commune of Phu Luong district, Thai Nguyen province, Vietnam where the agricultural activities are predominant occupation. The investigation on the use of plant protection products in here showed that chemical pesticides have been commonly used in agricultural activities. Although some local people have a good attitude in using plant protection products, the status of using chemical pesticides that were not recommended (like Vofatox) has been quite popular due to the old cultivation customs. The local people have not applied any measures for wastewater treatment, or plant protection product package treatment. Besides, the use of plant protection products in higher concentration than recommendation for vegetables or crops caused the residues of toxics in agricultural products as well as in cultivation soil. The accumulation of toxic residues in the environment is a serious matter of concern because of their significant impact on the environment, agricultural ecosystem and human health. / Phấn Mễ là một xã trung du miền núi của huyện Phú Lương, tỉnh Thái Nguyên, Việt Nam với hoạt động sản xuất nông nghiệp là chủ yếu. Qua thực tế điều tra tình hình sử dụng thuốc bảo vệ thực vật (BVTV) tại đây cho thấy hầu hết các loại hình sản xuất nông nghiệp đều sử dụng thuốc BVTV. Một số người dân đã có ý thức trong việc sử dụng thuốc BVTV tuy nhiên do tập quán canh tác từ lâu đời nên việc sử dụng các loại thuốc bị khuyến cáo, chẳng hạn như Vofatox, vẫn còn khá phổ biến. Người dân chưa tiến hành các biện pháp để xử lý nước thải, bao bì, vỏ chai thuốc BVTV sau khi sử dụng. Bên canh đó, họ còn sử dụng thuốc BVTV không đúng liều lượng cho một số loại cây rau để lại dư lượng thuốc trên nông sản cũng như đất canh tác. Sự tích lũy dư lượng của những chất độc hại này trong môi trường là vấn đề đáng lo ngại do sự ảnh hưởng nghiêm trọng của chúng đối với môi trường sống, hệ sinh thái nông nghiệp và sức khỏe con người.

Este trabalho teve como objetivo avaliar a infectividade de estirpes fracas do Papaya ringspot virus - type W (PRSV-W) em plantas de melancia (Citrullus lanatus), em função da origem da estirpe fraca, da concentração e da espécie doadora do inóculo e da idade da planta-teste de melancia, inoculada mecanicamente. Também foi avaliado o efeito protetor dessas estirpes em plantas de melancia em casa de vegetação e em campo. A seleção de estirpes fracas do PRSV-W foi feita a partir de bolhas de folhas de melancia infectadas naturalmente em campo. A infectividade da estirpe fraca selecionada foi comparada com a das estirpes fracas PRSV-W-1 e PRSV-W-2, previamente selecionadas de bolhas de folhas de abobrinha de moita (Cucurbita pepo) 'Caserta' com mosaico. Como controle foi utilizada uma estirpe severa do vírus obtida de abobrinha de moita (PRSV-W-C). A avaliação do efeito da concentração e da espécie da planta fonte do inóculo na infectividade de plantas de melancia foi feita com extratos de 4, 8, 12 e 16 discos de folhas de abobrinha de moita e de melancia, infectadas separadamente com as estirpes fracas e severa, e diluídos em 2 mL de tampão fosfato. O efeito da idade da planta-teste de melancia na infectividade das estirpes fracas foi estudado comparando-se plantas inoculadas em quatro estádios de desenvolvimento, a partir do estádio cotiledonar, com inóculos das diferentes estirpes do PRSV-W extraídos de 12 discos foliares/2 mL de tampão. O efeito protetor da estirpe fraca obtida de bolhas de folhas de melancia com mosaico foi avaliado em plantas premunizadas e desafiadas com a estirpe PRSV-W-C, em casa de vegetação e em campo. Plantas de melancia premunizadas com as estirpes fracas PRSV-W-1 e PRSV-W-2 e plantas não protegidas também foram avaliadas no teste em campo. Foram avaliadas a proteção, com base nos sintomas, a produção e o conteúdo de açúcares (grau brix) dos frutos colhidos das plantas premunizadas e não premunizadas. Uma estirpe fraca do vírus, denominada PRSV-W-3, foi selecionada de bolhas de folhas de melancia com mosaico. Em todos os testes de infectividade em plantas de melancia, independente da concentração e da planta fonte do inóculo e do estádio de desenvolvimento da planta-teste inoculada, a estirpe fraca PRSV-W-3 apresentou taxas de infectividade semelhantes as das estirpes PRSV-W-1 e PRSV-W-2, chegando a 100% em alguns casos. A infectividade da estirpe severa PRSV-W-C foi de 100% em todos os testes. Aparentemente, a infectividade das três estirpes fracas foi mais diretamente afetada pela intensidade de fricção das folhas no momento da inoculação mecânica do que pelas variáveis estudadas. A estirpe fraca PRSV-W-3 protegeu as plantas de melancia contra a infecção e/ou manifestação da estirpe PRSV-W-C em casa de vegetação. Em campo, todas as plantas de melancia premunizadas com as três estirpes fracas também ficaram protegidas contra a estirpe severa utilizada no desafio. A produção das plantas premunizadas não diferiu estatisticamente entre si, nem mesmo daquelas inicialmente sadias infectadas em campo. O conteúdo de açúcares e a aparência da polpa dos frutos também foram semelhantes em todos os tratamentos. / The purpose of this work was to evaluate the infectivity of three mild strains of Papaya ringspot virus - type W (PRSV-W) on watermelon (Citrullus lanatus). The effect of the origin of the mild strain, the concentration of the inoculum, the species of the source of the inoculum and the age of the test-plant on the infectivity of mechanically inoculated watermelon were also evaluated. The protective effect of these mild strains on preimmunized watermelon plants was evaluated under greenhouse and field conditions. Mild strains were selected from blisters formed on mosaic leaves of naturally infected watermelon plants. The infectivity of the selected mild strain was compared with that of mild strains PRSV-W-1 and PRSV-W-2, which were previously obtained from blisters formed on mosaic leaves of zucchini squash (Cucurbita pepo cv. Caserta). A severe strain isolated from zucchini squash (PRSV-W-C) was used as control. The effect of the concentration and the species source of inoculum of the mild strains on the infectivity of watermelon plants was studied with inoculum extracted from 4, 8, 12 and 16 leaf discs of zucchini squash and watermelon plants, separately infected with the mild and severe strains, diluted in 2 mL of phosphate buffer. Four stages of development of watermelon plants, starting at the cotyledonal stage, were tested for the infectivity with the mild strains. Inocula were prepared with extracts of 12 leaf discs diluted in 2 mL of phosphate buffer. The protective effect of the mild strain selected from blisters on mosaic leaves of watermelon plants was evaluated on preimmunized plants challenge inoculated with severe strain PRSV-W-C, under greenhouse and field conditions. Watermelon plants preimmunized with mild strains PRSV-W-1 and PRSV-W-2 and unprotected plants were also included in the field trial. Protection was evaluated based on plant simptons, yield and sugar content in the fruits. One mild strain, named PRSV-W-3, was obtained from blisters on mosaic leaves of watermelon plants. The rate of infection of watermelon plants with mild strain PRSV-W-3 was similar to that with mild strains PRSV-W-1 and PRSV-W-2 in all infectivity tests, independently of the concentration of the inoculum, species source of the inoculum and stage of development of the inoculated test-plant, reaching 100% in some cases. Rate of infectivity with severe strain PRSV-W-C was always 100%. Apparently, the infectivity of the mild strains on watermelon was more directly related with the intensity of the abrasion produced by mechanical inoculation than with the above studied variables. The selected mild strain PRSV-W-3 protected watermelon plants against superinfection with the severe strain in the greenhouse tests. Protection was also effective under field conditions. Yield of plants preimmunized with all three mild strains and unprotected plants were statistically similar. The sugar content and the quality of the pulp of the fruits were similar for all treatments.

Os avanços na mecanização agrícola têm contribuído para o crescimento da produtividade agrícola do país, garantindo ao Brasil lugar de destaque na produção agrícola de alimentos, fibras e energia. A aplicação de produtos fitossanitários tem contribuído para esse aumento garantindo a proteção de plantas dentro do ciclo de produção agrícola. Controladores eletrônicos têm sido utilizados nas aplicações de produtos fitossanitários na agricultura moderna, surgindo à necessidade de estudos do seu desempenho. O tempo de resposta é o principal parâmetro, pois determina a eficiência do sistema de controle. Desta forma, objetivo deste trabalho foi estudar o tempo de resposta de um controlador eletrônico de pulverização variando as velocidades de deslocamento e taxas de aplicação, em baixas, médias e altas vazões. As mudanças de velocidade de deslocamento e as de taxa de aplicação influenciaram nos tempos de resposta no controlador eletrônico de pulverização. Os tempos de resposta obtidos do controlador eletrônicos de pulverização para mudanças de velocidade e taxa de aplicação variaram de 2 a 9 e 1,5 a 8 segundos respectivamente. A exatidão do sistema de controle eletrônico de pulverização para as mudança de velocidade foi de ± 2% e para as mudanças de taxas de aplicação de ± 4%. O controlador eletrônico de pulverização obteve menor tempo resposta em altas vazões e maiores velocidades. / Advances in agricultural mechanization contributed to the growth of productivity in the country farms, leading Brazil to a significant position in the agricultural production of food, fibre and energy. A fraction of these results had been ensured by employment of plant protection products within the cycle of agricultural production. In this context, electronic controllers have been used in spraying applications and creating a demand for studies of their performance. Response time in actual applications is a key parameter determining the efficiency of the control system. The objective of this work was to study the response time of an electronic controller of: varying displacement speeds, spraying, and application rates; working at low, medium and high flows. Influences in the response time were found for speed changes and the application rates in spray electronic controller. Ranging from 2 to 9 and 1.5 to 8 seconds respectively. The accuracy of electronic spray control system for gear change was up to 2% and to changes in application rates up to 4%. Time responses for the electronic controller were lower for high flow rates and speeds.

De nos jours, il y a une volonté générale de se tourner vers une agriculture plus respectueuse de l’environnement et du consommateur se traduisant notamment par une démarche de réduction des intrants chimiques. Dans un contexte de développement durable, la recherche de produits naturels pour lutter contre les maladies et les ravageurs suscite un regain d’intérêt. Dans cette thèse, des extraits hydro-alcooliques issus de coproduits de la vigne (sarment, cep, racine) et d’essences forestières (écorce d'épicéa, nœud de pin) se sont révélés être une excellente source de polyphénols bioactifs, en particulier en stilbènes complexes. En effet, ces extraits ont démontré un large spectre d’activités contre différentes maladies végétales. En particulier, un potentiel oomycide contre le mildiou de la vigne et une capacité insecticide contre un parasite des Solanacées sont rapportés. En outre, la pertinence de l'utilisation de la « chimie verte » pour extraire les stilbènes comme méthode alternative aux solvants organiques a été mise en évidence. Les présents résultats renforcent une voie de recherche originale pour faire progresser une viticulture et une agriculture plus durables, en utilisant des produits de biocontrôle moins toxiques et biodégradables, constituant ainsi une solution possible et réaliste pour lutter contre les pathogènes des plantes. / Nowadays, is a priority to turn towards a more eco- and consumer friendly agriculture resulting in the reduction of the chemical inputs. In a context of a sustainable development, the investigation of natural products to fight against diseases and pests raised a renewed interest. In this thesis, hydroalcoholic extracts derived from grapevine (cane, wood, root) and forest species (spruce bark, pine knot) by-products have demonstrated to be a great source of bioactive polyphenols, and particularly in complex stilbenes. Indeed, these extracts have proved to confer a broad spectrum of activities against different major plant diseases. In particular, an oomycide potential against downy mildew of the vine and an insecticidal capacity against Solanaceae pest were reported. Furthermore, the relevant use of “green chemistry” to extract stilbenes as an alternative method of organic solvents has been highlighted. The present findings strengthen an original line of research to advance in a more sustainable viticulture and agriculture, using less toxic and biodegradable biocontrol products, being this a possible and realistic solution to combat plant pathogens.

Os avanços na mecanização agrícola têm contribuído para o crescimento da produtividade agrícola do país, garantindo ao Brasil lugar de destaque na produção agrícola de alimentos, fibras e energia. A aplicação de produtos fitossanitários tem contribuído para esse aumento garantindo a proteção de plantas dentro do ciclo de produção agrícola. Controladores eletrônicos têm sido utilizados nas aplicações de produtos fitossanitários na agricultura moderna, surgindo à necessidade de estudos do seu desempenho. O tempo de resposta é o principal parâmetro, pois determina a eficiência do sistema de controle. Desta forma, objetivo deste trabalho foi estudar o tempo de resposta de um controlador eletrônico de pulverização variando as velocidades de deslocamento e taxas de aplicação, em baixas, médias e altas vazões. As mudanças de velocidade de deslocamento e as de taxa de aplicação influenciaram nos tempos de resposta no controlador eletrônico de pulverização. Os tempos de resposta obtidos do controlador eletrônicos de pulverização para mudanças de velocidade e taxa de aplicação variaram de 2 a 9 e 1,5 a 8 segundos respectivamente. A exatidão do sistema de controle eletrônico de pulverização para as mudança de velocidade foi de ± 2% e para as mudanças de taxas de aplicação de ± 4%. O controlador eletrônico de pulverização obteve menor tempo resposta em altas vazões e maiores velocidades. / Advances in agricultural mechanization contributed to the growth of productivity in the country farms, leading Brazil to a significant position in the agricultural production of food, fibre and energy. A fraction of these results had been ensured by employment of plant protection products within the cycle of agricultural production. In this context, electronic controllers have been used in spraying applications and creating a demand for studies of their performance. Response time in actual applications is a key parameter determining the efficiency of the control system. The objective of this work was to study the response time of an electronic controller of: varying displacement speeds, spraying, and application rates; working at low, medium and high flows. Influences in the response time were found for speed changes and the application rates in spray electronic controller. Ranging from 2 to 9 and 1.5 to 8 seconds respectively. The accuracy of electronic spray control system for gear change was up to 2% and to changes in application rates up to 4%. Time responses for the electronic controller were lower for high flow rates and speeds.

A great effort has been recently devoted to the development of new devices for the detection of specific sequences of DNA, due to increasing need of label - free, fast, cheap, and miniaturized analytical systems able to detect target sequences for screening purposes, especially in food industry for genetically modified organisms (GMOs). In this study, development of a QCM - based DNA biosensor for the detection of the hybridisation of CaMV 35S promoter sequence (P35S) was investigated. Attention was focused on the choice of the coating chemistry that could be used for the immobilisation of probe sequences on the gold surface of the quartz crystal. Two immobilisation procedures were tested and compared considering the amount of the immobilised probe, the extent of the hybridisation reaction, the possibility of regeneration and the absence of non - specific adsorption. The two coating methods were based on the use of self - assembled monolayers. One of them employed the interaction between the thiol and gold for the immobilisation of a thiolated P35S probe, while the other employed formation of functionalised aldehyde groups by ethylenediamine plasma polymerization on the gold surface for the immobilisation of amined P35S probes through gluteraldehyde activation. Results indicated that immobilisation of a thiolated probe provides better immobilisation characteristic, higher sensitivity for the detection of the hybridisation reaction, absence of non - specific adsorption and a higher stability with respect to the regeneration step. The optimised immobilisation procedure for the thiolated probe was used for the detection of P35S sequence in PCR - amplified DNAs and in real samples of pflp - gene inserted tobacco plants that produce ferrodoxin like protein additionally. Fragmentation of the genomic DNAs were achieved by digestion with restriction endonucleases and sonication. The obtained results from the fragmented genomic DNAs demonstrated that it is possible to detect the target sequence directly in non-amplified genomic DNAs by using the developed QCM - based DNA biosensor system. The developed QCM-based DNA biosensor represented promising results for a real-time, label - free, direct detection of DNA samples for the screening of GMOs.