Chemical Control

O ectoparasita Rhipicephalus (Boophilus) microplus, como os outros carrapatos, precisa de um amplo arcabouço de enzimas, peptídeos e outras moléculas anticoagulantes para contrapor a homeostase do hospedeiro e a ingestão adequada de sangue. Tais anticoagulantes estão presentes na saliva dos hematófagos, pois ela é o primeiro contato entre o sangue e o aparato bucal deste. Anteriormente, nosso grupo de pesquisa encontrou na saliva de R. microlus um peptídeo de 16 aminoácidos (1,7kDa) com atividade anticoagulante, denominado microfilina. Dados preliminares sugerem que esse peptídeo age no exosítio I da trombina. Entretanto, a sequência de aminoácidos da microfilina, que pode indicar um perfil anticoagulante interessante para a fabricação de novos fármacos, ainda não é conhecida, impedindo sua caracterização. Para caracterizar essa molécula, é preciso obtê-la em quantidades adequadas e, portanto, coletar saliva do carrapato para que se possa extrair a microfilina. Até o momento foram coletados aproximadamente 1,5 ml de saliva (rendimento de 0,8 l por carrapato), quantidade ainda insuficiente para os trabalhos de caracterização, os quais terão início assim que a saliva necessária for obtida. Por outro lado, em seu trabalho de mestrado, XAVIER, M. A. (Programa de Pós-Graduação em Biologia Celular e Molecular, UFRGS, 2016) identificou proteínas do intestino do mesmo parasita com a propriedade de inibir trombina (purificadas em colunas de cromatografia de troca iônica, de gel filtração e de afinidade por trombina). Análises por espectrometria de massas mostrou que, entre esses inibidores de trombina, a catepsina B foi a proteína que apresentou maiores contagens espectrais. Por isso, essa enzima foi selecionada para estudos mais detalhados. A expressão dessa enzima em sistema heterólogo foi escolhida como metodologia para se obter a quantidade devida para a caracterização. A fase de leitura aberta (ORF-Open Reading Frame) do gene desta proteína já estava subclonada no vetor de clonagem pGEM-T, formando a construção pGEM-CB (vetor de clonagem com o gene de catepsina B). No estágio atual do projeto este gene está em fase de clonagem no vetor de expressão pET 43a. O inserto com a região codificante da catepsina B já foi devidamente (i) transformado em células Escherichia coli TOP10 por choque térmico; (ii) extraído destas células por extração plasmidial de larga escala, midiprep; (iii) analisado com as enzimas de restrição compatíveis BamHI e NdeI; (iv) desfosforilado; (v) purificado de gel de agarose após clivagem com endonucleases, e (vi) ligado no vetor de expressão. Na próxima etapa do trabalho, bactérias E. coli competentes serão transformadas com este vetor por meio de técnica de eletroporação e analisadas quanto à capacidade de expressão da catepsina B de carrapato.

A major problem in insect pest and weed management is uncertainty. Managers are faced with three main types of uncertainty: uncertainty about biological and environmental processes, and observational uncertainty. Active adaptive management (AAM) is management with a deliberate plan for learning about the managed system, so that management can be improved in the face of uncertainty. We discuss the potential benefits of applying AAM to insect pest and weed control with reference to a number of examples. We first address the possible uses for AAM in biological control, with particular reference to agent selection and release. We also propose applying AAM methods to resistance management and to spatial strategies for pest control. We conclude with an overview of AAM, a discussion of some of the potential limitations to its use in pest management, and the possibilities for increased implementation of AAM in the future.

Termites cause a wide array of damages to plantations, trees and manmade structures. Both industrial and food crops as well as forest trees are attacked by termite. Reports on economic losses caused by termite infestations have been made worldwide. The objective was to identify suitable and sustainable indigenous methods adopted by resource poor farmers for termite control. Semistructured questionnaires were administered to 20 farmers in each of the selected communities who practiced indigenous termite control methods. A total of 100 farmers were interviewed, who had applied various indigenous treatments on their crop fields against termite infestation. The study recorded a total of 24 termite species, which varied in presence at each locality, with a few serious pest species damaging agricultural products such as maize, yam, millet, and other natural resources in the area. Five termite prevention and control methods were identified: (i) burial of plant and animal materials, (ii) ap...

The shoot and fruit borer (Leucinodes orbonalis G.) is one of the major insect pests of the brinjal crop. Presently, farmers use synthetic insecticides to control this pest, which can cause health and environmental problems. Therefore, the goal of this study was to determine the performance of various botanical pesticides (neem, eucalyptus, karanj, and mahogany oils at 1%) against L. orbonalis under field conditions during 2023, after the 1 st and 2 nd sprays at 1, 3, and 7 days post-application. The results showed that all botanical pesticides were effective in reducing the shoot and fruit damage percentages after the 1 st and 2 nd sprays at all intervals compared to the control, with neem oil being the most effective in reducing the shoot and fruit damage percentages of L. orbonalis. The lowest shoot and fruit damage percentages were observed after the 1 st and 2 nd sprays at the 7-day interval with neem oil: shoot damage percentages were 12.5% and 9.8%, and fruit damage percentages were 22.2% and 12.4%, respectively. Similarly, the highest yield was obtained (13,013 kg/ha) when the crop was treated with neem oil, followed by eucalyptus, karanj, and mahogany oils at 1% with yields of 11,307, 10,499, and 9,947 kg/ha, respectively, whereas the minimum yield of 5,603 kg/ha of fruits was obtained in the control. Therefore, based on the present results, all botanical pesticides are highly recommended, with Neem oil being the most effective against the shoot and fruit borer.

This background study paper is made available to the Commission on Genetic Resources for Food and Agriculture to inform decision-making on future work on micro-organisms and insects, in the context of its Multi-Year Programme of Work. This is a preliminary version of the study, it has been published in order to support preparation of the Commission's Eleventh Session. A final version will soon be issued within the background study papers series of the Commission.

The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has invaded most Afro-Eurasian countries, and is threatening worldwide tomato production. Various strategies have been developed and implemented to manage this pest species. Here we present a timely review on the up-to-date development and practical implementation of Integrated Pest Management (IPM) programs for tomato crops across different regions infested by T. absoluta. While insecticide resistance is a growing concern, biological control via releasing or conserving arthropod natural enemies and sex pheromone-based biotechnical control are the most successful management practices. Agronomic control-related research is an emerging area where the soil fertilization and/or irrigation, as well as breeding of resistant cultivars, have the potential to enhance IPM efficacy. Surveys in the native areas (i.e. South America), early-invaded areas (i.e. first report between 2006-2012) and newly-invaded areas (i.e. first report after 2012) showed that the progams used by growers evolved along with the areas and time since invasion. Growers in the early-invaded areas shifted more rapidly from chemical control to biological control compared to those from the native area. For all areas, the greatest concern is related to control failure risk following chemical insecticide applications and the high cost associated with either biological or biotechnical control methods. The information gathered from the native and/or early-invaded areas may help achieve a more effective management in newly-invaded areas. Lastly, researchers are expected to break the bottlenecks of some key issues that would enable lowering application cost of novel biorational alternative management options.

Background: A recent occurrence of fall armyworm (FAW), Spodoptera frugiperda (JE Smith) a new invasive pest in Africa attained epidemic form in 2016. Consequently, researchers probed various ecofriendly methods to manage the pest. The effect of intercropping cowpea [Vigna unguiculata (L.) Walp.] with fodder maize (Zea mays L.) on the incidence of FAW was investigated. M ethods: The maize fodder was protected against FAW by intercropping with cowpea along with a biorational product, Brahamastra and compared with the recommended insecticide used to manage the insect by conducting field experiments during

La enfermedad del moko, causada por Ralstonia solanacearum, es uno de los problemas fitosanitarios más importantes de la agroindustria bananera de Urabá. Esta bacteria se caracteriza por presentar una gran plasticidad genética, lo cual dificulta el diseño de estrategias para su control. Con el fin de determinar los componentes del complejo de especies de R. solanacearum presentes en la región de Urabá, en esta investigación se realizó la caracterización genotípica de una población de R. solanacearum procedente de plantas de banano, arvenses y suelos de diversas plantaciones de esta zona. La evaluación se realizó mediante PCR múltiple y secuenciación de tres regiones del genoma (genes egl, fliC y región 16S del ADNr). Los resultados indican que todas las cepas bacteriales estudiadas están asociadas al filotipo II, y en su mayoría pertenecen al secuevar 4, aunque en el caso de algunos aislamientos no fue posible su filiación con ninguno de los tres secuevares reportados para la raza 2. Dos aislamientos obtenidos del departamento del Magdalena, utilizados con fines comparativos, resultaron estar asociados al secuevar 6. Los resultados de esta investigación plantean importantes aspectos epidemiológicos a ser tenidos en cuenta en el manejo de la enfermedad del moko en las plantaciones de banano del Urabá antioqueño. Moko disease, caused by Ralstonia solanacearum, is one of the most important phytopathological problems of the banana agribusiness in Uraba (Colombia). This bacterium is featured by having high genetic plasticity, which difficults the design of control strategies. The aim of the present research was to establish the components of the R. solanacearum species complex, through the study of the genotypic features of a series of strains isolated from banana plants, weeds and soils from different plantations in Uraba. The analysis was carried out through multiple PCR and sequencing of three genomic regions (egl and fliC genes, and region 16S of 16S rDNA). The results indicate that all the studied isolates are associated to phylotype II, and most of them belong to sequevar 4. However, in the case of some strains, it was not possible to associate the PCR results with the sequevars that have been reported for race 2. Interestingly, two isolates from the department of Magdalena used as comparative controls for the bacterial population of Uraba, were found to belong to sequevar 6. These results raise important epidemiological aspects of the management of moko disease in the banana growing region of Uraba.

El Valle de Zamora, Michoacán, es la zona productora de fresa (Fragariaananassa Duchesne) más importante de México. En este valle y en muchas otras regiones de México la araña roja Tetranychus urticae Koch es la principal plaga de este cultivo; Su combate se ...

The most important stored grain pests in Brazil are: Sitophilus zeamais, Sitophilus oryzae, Sitotroga cerealella and Rhyzopertha dominica. One alternative to chemical control of storedproduct insects on small farms in the tropics are the storage of silage prepared from triturated whole corn and sorghum plants. This kind of food is particularly good as animal feed, mainly for beef and dairy cattle. Other type of silage can be prepared from triturated and compressed whole humid corn grain (38 % water content). The quality preservation of the silage is based on the process of fermentation in which does not occurs insects and mold development. Another alternative has been demonstrated to be efficient is the use of diatomaceous earth, which insecticide activity is based on physical properties. Hermetic storage, a system based on consumption of the oxygen by the metabolic activity of the seeds, and under very low concentration of oxygen and higher concentration of CO2, insect and fungus development are suppressed. In Brazil, it is commercially available a product called "SILO BAG" made of a machine to load grains into a 3m diameter a plastic bag that can be 100m long and able to store up to 200 tons of corn, soybeans, wheat and sorghum under hermetic conditions. In Brazil a significant proportion (from 20 to 30%) of harvested corn production is stored on the husk by the small farmers. Good husk protection and grain hardness have been incorporated in the varieties to protect grain against the stored grain pests and fungus. Another possibility, but less effective, is the use of botanic material that have repellent action to the pests, as for example eucalyptus three leaves distributed in layers between the husks.

The aim was to evaluate the potential of alternative and chemical products on the control of Monilinia fructicola, causal agent of brown rot, in vitro and in post-harvest of peach fruits. The treatments consisted of plant extracts of cinnamon (CI), clove (CL), boldo (BO), potassium phosphite (PP), fungicide tebuconazole (FT) and control with water (CO). For the in vitro experiment, it was evaluated mycelial growth (MG), velocity index of mycelial growth (VIMG) and percentage of growth inhibition (PGI). For post-harvest, peach fruits of two cultivars (Chimarrita and Precocinho) were to immersion in the mentioned treatments (besides acibenzolar-S-methyl (ASM) for Chimarrita cv). Was evaluated the severity of the disease through disease index (%) and area under the disease progress curve (AUDPC). The fungicide tebuconazole inhibited the MG in vitro and in vivo. The extract of CL and PP reduced the MG and MGRI, with the highest PGI. PP and ASM reduced the development of the disease in vivo, with promising results for Chimarrita. Alternative controls such as plant extracts, phosphites and acids reduce brown rot in peach fruits.

For a country to develop high-performance sport, it is essential to have the human capital that has the qualities to become a champion. This feature does not guarantee success but offers more possibilities. There are many questions about how to select a sports talent and when to consider someone as a talent for a specific sport. For the development of this process, it is necessary to take into account that sports training is a pedagogical process of teaching and learning, governed by biological and pedagogical principles and laws. For identifying sports talents, there are different selection criteria: pedagogical, medical-biological, sociological, and psychological. It is also important to comply with the methodological guidelines established for the development of the physical capacities of children, according to the different ages and periods of maturation. This article aims to reflect on the fundamental characteristics of the process of selection of talent and initiation of sports, and thus provide information to sports coaches on how they can develop their work.

O objetivo do presente trabalho foi avaliar o efeito de espectros de gotas (grossas, médias e finas) na velocidade de absorção de fungicidas, para trifólios de diferentes idades, através de medida indireta expressa pelo residual de controle de ferrugem asiática da soja (Phakopsora pachyrhizi). O delineamento experimental utilizado foi inteiramente casualizado, com quatro repetições, em arranjo fatorial (3x3x5x4), cujos fatores foram compostos por: três espectros de gotas (grossas, médias e finas); três idades fisiológicas de trifólios na planta (1°, 3° e 5° trifólios); quatro períodos de tempo entre a aplicação de fungicidas e chuva simulada (0, 30, 60 e 120min.), mais uma testemunha sem chuva; três tratamentos com fungicida: azoxistrobina + ciproconazol (60+24g i.a. ha-1) + óleo mineral 0,6L ha-1, azoxistrobina (50g i.a. ha-1) + óleo mineral 0,6L ha-1 e ciproconazol (30g i.a. ha-1), mais uma testemunha sem aplicação. Avaliou-se densidade de gotas por centímetro quadrado, diâmetro m...

O objetivo do presente trabalho foi avaliar o efeito de espectros de gotas (grossas, médias e finas) na velocidade de absorção de fungicidas, para trifólios de diferentes idades através de medida indireta expressa pelo residual de controle de ferrugem asiática da soja (Phakopsora pachyrhizi). O delineamento experimental utilizado foi inteiramente casualizado, com quatro repetições, em arranjo fatorial (3x3x5x4), cujos fatores foram compostos por: três categorias de gotas (grossas, médias e finas); três diferentes posições de avaliação na planta (1°, 3° e 5° trifólios); quatro períodos de tempo entre a aplicação de fungicidas e aplicação de chuva simulada (0, 30, 60 e 120min), mais uma testemunha sem chuva; testemunha sem aplicação, mais os fungicidas azoxistrobina + ciproconazol (60+24g i.a. ha-1) + óleo mineral 0,6L ha-1, azoxistrobina (50g i.a. ha-1) + óleo mineral 0,6L ha-1 e ciproconazol (30g i.a. ha-1). Avaliou-se a densidade de gotas por centímetro quadrado, diâmetro mediano v...

Com este trabalho, buscou-se avaliar a resposta de cultivares de soja, em duas safras, submetidas a diferentes espaçamentos entrelinhas e programas de controle sob pressão natural de Phakopsora pachyrhizi Sidow. Nas safras 07/08 e 08/ 09, os espaçamentos entrelinhas de 40, 50 e 60cm representavam as parcelas principais, as cultivares 'A 8000 RG' e 'A 6001 RG', as subparcelas e os programas de controle, as subsubparcelas. A redução do espaçamento entrelinhas permitiu melhores condições para o estabelecimento e progresso da ferrugem asiática para as duas cultivares e menor eficácia de controle. A melhor resposta de controle foi verificada com a utilização do programa após uma aplicação no estádio de desenvolvimento R1 e uma segunda aplicação 25 dias após a primeira. O espaçamento de 60cm entrelinhas proporcionou menores valores de doença acumulada e maior produtividade. Palavras-chave: ferrugem asiática da soja, controle químico, programa de manejo de doença.

O controle das doenças foliares na cultura da soja pode ser obtido pela utilização de métodos genéticos, culturais e químicos. A utilização de ativadores químicos dos mecanismos de defesa é uma alternativa de controle induzido. Para avaliar o efeito na eficácia com a inclusão de Acibenzolar-S-Methyl (ASM) no programa de controle químico das doenças foliares na cultura da soja, um experimento foi instalado com as cultivares IAS 5, CD 201 e RS 10. O efeito do ASM foi avaliada isoladamente e em mistura com Difenoconazole aplicados nos estádios R3, R4 e R5.1 e o Azoxystrobin em R5.1. Os parâmetros avaliados foram a severidade das doenças de final de ciclo (DFC), desfolha, área foliar verde e rendimento de grãos. A inclusão de ASM nos programas de controle químico aumentou, na maioria dos casos, a eficácia dos fungicidas para todos os parâmetros avaliados, porém com variação entre as cultivares. Os melhores resultados foram obtidos com aplicações de Difenoconazole + ASM aplicado em R3 e ...

A eficiência de diferentes doses de fungicidas aplicados em diversos estádios fenológicos da soja foi avaliada no controle de Phakopsora pachyrhizi. As cultivares de soja utilizadas nos experimentos foram RS 10, BRS 154, CD 201, BRS 153, CD 206 e CD 209, sendo conduzidos em condições de campo sob infecção natural do patógeno. Os resultados obtidos demonstraram variação significativa no rendimento quando duas aplicações de fungicidas foram realizadas. A seqüência de fungicidas utilizados bem como o inóculo presente na área experimental evidenciaram a eficácia de controle da ferrugem. Fungicidas do grupo das estrobirulinas aplicados no estádio R1 apresentaram o melhor desempenho, e o controle executado preventivamente possibilitou a maior efetividade.

The productivity of the rice is affected by several factors, among which are the diseases caused by fungus that can cause reduction in yield, in the physiologic and sanitary quality of the seed. The objective of this work was to verify the loss in yield caused by leaf diseases in irrigated rice and the efficiency of fungicides control with one or two applications. The experiment was conducted in the municipal district of Eldorado do Sul - RS, harvest year 2003/04. The treatments consisted of fungicides belonging to the chemical groups of the triazoles and strobirulins and mixtures of these, applied in cultivating SCS 112 (Epagri). The applications were made at the stage 32 (panicle formation) and repeated in 55 (50% of the emerged panicle). Evaluated variables were the severity of the diseases in the leaves and in the grains, green leaf area and grain yield. leaf diseases and spots of the grains affected grain yield up to 42.10%. The best control was verified for the diseases with l...

O objetivo desse trabalho foi avaliar o efeito de sete doses de cálcio (zero; 49,5: 99,0: 148,5: 198,0; 247,5 e 297,0 kg.ha -1 ) e dois níveis de sombreamento (sombra, pleno sol) em um sistema fatorial de 7x2. Palavras chave: manejo de doença, ferrugem, Glycine max.

O objetivo deste trabalho foi avaliar a interferência das doenças foliares na produtividade de duas cultivares de arroz irrigado, bem como determinar a interação entre ingredientes ativos e momento de aplicação, para o controle de escaldadura e mancha-marrom. Foram utilizados: tiofanato metílico, tebuconazole, azoxystrobin e trifloxystrobin + propiconazole, aplicados em cinco épocas, às cultivares IRGA 417 e El Passo L 144. Os parâmetros avaliados foram: severidade das doenças e rendimento de grãos. O controle químico proporcionou redução significativa na severidade das doenças, em ambas as cultivares, com reflexo no rendimento de grãos, e foi influenciado pelo produto e pela época de aplicação.

Production of sizable amount of food is mandatory to feed the world's inflating population. This gospel truth has prompted the creation and widespread use of synthetic pesticides as a rapid and efficient method of controlling agricultural pests. However, excessive dependence on synthetic pesticides is discouraged because of the harm they do to the environment, people's health, and building of insect pest's resistance. These rationales together with the rising preference for foods grown organically sparked a search for alternative methods of pest control. To establish sustainability within the agricultural ecosystem, adoption of Good Agricultural Practices and effective strategies of Integrated Pest Management are indispensable. Constructive utilization of these management practices adds economic advantages in the form of continued development, higher productivity, and decreased pest damage for a better and healthier environment, which has got longterm benefits for everyone.

Effect of water stress on herbicide efficiency applied to Urochloa decumbens. Cien. Inv. Agr. 39(1): 211-220. This project aimed to measure the control efficiency of Acetil Coenzime A Carboxilase (ACCase)-inhibiting herbicides post-emergence applied to Urochloa decumbens (Stapf) R.D. Webster under different soil water contents. The experiment was conducted in a greenhouse at the

The leaf rust is the most common disease in wheat, being responsible for productivity losses exceeding 50%. The objective of the present work was to evaluate the effect of six times of fungicide spray on wheat leaf rust control and yield potential in different cultivars. The experimental design was randomized blocks, in a split-plot with four divided replications, with the main portion comprising CD 104, CD 105, CD 111, CD 114, CD 116 and CD 117 cultivars, and sub-plot comprising the spray moments (1-elongation, 2-booting, heading and 3-stretching; 4-booting and flowering; 5-elongation, booting and flowering, and 6-control). Final severity and yield were evaluated. The variables were submitted to compare means. The results confirmed the behavior of cultivars in control plots. There were significant differences between the times of application in all cultivars, except CD 116 did not respond to chemical control, but responded in grain yield.

The oviposition preference of Helicoverpa armigera on six tomato varieties (Red King, Rio Grande, Florida King, Roma, Sahel, and 1359) was evaluated through freechoice and no-choice tests at Tarnab Farm, Peshawar, Pakistan, to identify extremes for potential IPM integration. In free-choice tests, Rio Grande received significantly (P < 0.05) more eggs (mean 324.5; ROP 24.8) than all other varieties, followed by Roma (309.6; ROP 23.7) and Florida King (265.4; ROP 20.3). Red King (194.3; ROP 14.8) and 1359 (201.7; ROP 15.4) were less preferred, while Sahel (150.9; ROP 11.5) was least preferred. No-choice tests confirmed Rio Grande as most preferred (325.4; ROP 24.9) and Sahel as least preferred (160.3; ROP 12.1), with Roma consistently ranked second (310.1; ROP 23.8). Electrical Penetration Graph (EPG) analysis under whole-plant conditions revealed significant (P < 0.05) differences among varieties in number of probes, total probing duration, and pathway phase parameters. Rio Grande recorded the highest values, followed by Florida King and Roma; Red King and Sahel exhibited the lowest, indicating reduced feeding activity. Under detached-leaf conditions, no significant differences were observed, suggesting uniform feeding behaviour in the absence of wholeplant cues. On the whole, oviposition and feeding behaviour of H. armigera were strongly influenced by varietal characteristics. Sahel, Red King, and 1359 were identified as less susceptible, making them promising for pest-resistant cropping systems. Incorporating such varieties into IPM programs can reduce H. armigera impact and reliance on chemical control.

Fusarium wilt, caused by Fusarium oxysporum f.sp. dianthi (FOD), is one of the most devastating carnation diseases globally, resulting in significant crop loss (40-70%). The purpose of this study was to determine the efficacy of several fungicides against Fusarium wilt of carnation in vitro and in vivo under protected cultivation. The disease infected plant samples were collected, and pathogen isolates were confirmed through morphological and molecular techniques. The rDNA sequences of isolates had 97-100% similarity with other sequences of FOD available in Genbank and the isolates were identified as Fusarium oxysporum f.sp. dianthi. Phylogenetic analysis of rDNA sequences revealed 62-99% sequence similarity among the isolates. Further, we evaluated nine different fungicides against the virulent pathogenic isolate CFODTNAU1 under in vitro and in vivo. Three different concentrations such as 500, 1000 and 1500 ppm were evaluated on mycelial growth of the pathogen under in vitro and percent inhibition over control was calculated. Among the fungicides, three of them namely, tebuconazole 50% + trifloxystrobin 25% WG, tebuconazole 25.9% SC and azoxystrobin 23% EC completely inhibited (100% inhibition) the mycelial growth of the fungus in vitro. Under protected cultivation, application of tebuconazole 50% + trifloxystrobin 25% WG through root dipping and soil drenching @ 1.0 g/L recorded 11.11% of wilt incidence compared to control (29.71% wilt incidence), which was 59.99% reduction over control. Besides, this fungicide also increased the stem length, earliness of flowering and yield than the control and other treatments. Thus, the fungicide tebuconazole 50% + trifloxystrobin 25% WG can be used for amelioration and control of wilt disease in carnation.

Ditylenchus gigas Vovlas is the dominant species of Ditylenchus nematode on faba bean in the UK. It is normally reported with Botrytis fabae Sardiña, which causes chocolate spot of faba bean. The aim of the work reported here was to estimate how fast isolated infections of D. gigas may spread spatially and how background infection

This study was conducted using seeds in Petri dish containing agar medium in order to determine acetyl-CoA carboxylase (ACCase) herbicides resistance (R) in Avena sterilis that was grown in wheat fields at Adana province, Turkey. Seeds were collected from one large suspected field, where clodinafop-propargyl (Aryloxyphenoxypropionate "FOPs") and pinoxaden (Phenylpyrazoline "DEN") have been applied for many years. Susceptible (S) population was collected from the road side on the same region. Agar media of concentration 14 g/L was prepared and it was melted in microwave. Then the amount of 20 mL agar media was added into each Petri dish. Five seeds were placed on agar mediums containing discriminating dose of clodinafop and pinoxaden. Petri dishes were placed in growth incubator operating at 10 °C. After 15 d, both radicle and hypocotyl length were measured. The percentage of germinated seed and dose-response curves were determined. At these different concentration levels, there were more than 50% of R and less than 40% of S seed germinated for pinoxaden. However, for clodinafop, more than 60% of R and less than 50% of S seeds were germinated. At higher concentration levels, the populations of resistant and susceptible were not germinated for both herbicides. The resistance value of R population was then compared with that of the S biotype. From the resistance index (RI), the population was more resistant to pinoxaden (7.43 for radicle and 2.47 for hypocotyl) than the clodinafop-propagyl (1.39 for radicle and 3.77 for hypocotyl). The method provided a simple, quick and cost effective way to identify ACCase herbicides resistance in most grass weeds.

In many northern regions of the United States, gastrointestinal nematode infections are largely subclinical, with relatively few cases of clinical disease. At subclinical levels the effects of nematodes are less apparent but lead to decreased rates of production and decreased immunity to various infectious diseases. Subclinical burdens may make it difficult for producers to recognize the loss, and the need to control these parasites. A convenient method to measure subclinical losses under actual herd production conditions is needed to enhance producers&#39; ability to evaluate the cost-benefit of nematode control programs. The objective of this project was to evaluate an epidemiologic-based methodology, which measures losses due to subclinical gastrointestinal nematode infections in yearling cattle on a single pasture.

Wild oat (Avena fatua L.) and false cleavers (Galium spurium L.) are currently a challenge to manage in less competitive crops such as flax (Linum usitatissimum L.). Increasing the functional diversity in crop rotations can be an option to improve weed management. Nonetheless, this strategy had not been tested in flax in western Canada. A 5-yr (2015 to 2019) crop rotation study was carried at three locations in western Canada to determine the effect of diverse flax-based crop rotations with differences in crop species, crop life cycles, harvesting time, and reduced herbicides on managing A. fatua and G. spurium. The perennial rotation (flax–alfalfa [Medicago sativa L.]–alfalfa–alfalfa–flax) under reduced herbicide use was found to be the most consistent cropping system, providing A. fatua and G. spurium control similar to the conventional annual flax crop rotation (flax–barley [Hordeum vulgare L.]–flax–oat [Avena sativa L.]–flax) with standard herbicides. At Carman, this alfalfa rot...

Au Maroc, les travaux sur les champignons sont rares et aucune liste complete qui repertorie les especes d&#39;une region donnee n&#39;est encore disponible. L&#39;objectif de ce travail est d&#39;etudier la flore fongique au niveau de la Mamora, Moyen Atlas et le Rif. Des prospections effectuees dans ces regions et la determination des criteres macroscopiques et microscopiques ont permis de determiner pour la premiere fois au Maroc deux especes du genre Polyporus: Polyporus arcularius Batsch : Fr. et Polyporus meridionalis (A. David). Cette etude s&#39;integre dans la contribution a la determination de la diversite fongique du Maroc, qui demeure jusqu&#39;a present incomplete. Mots cles : Champignons, Maroc, foret, Polyporus Arcularius, Polyporus meridionali s. FIRST HARVEST OF TWO FUNGAL SPECIES OF THE Polyporus GENUS IN MOROCCO : Polyporus arcularius BATSCH : FR. AND Polyporus meridionalis (A. DAVID) JAHN In Morocco, the works on mushrooms are rare and no complete list that lists...

In order to investigate the effect of sulfosulfuron, metsulfuron-methyl plus sulfosulfuron, mesosulfuron-methyl plus iodosulfuronmethyl and iodosulfuron plus mesosulfuron on weed control and wheat biological and grain yield, a two-year field experiment was conducted in Shiraz, Iran, during 2011-2012 and 2012-2013 growing seasons. The experimental design was randomized complete blocks with four replications. Treatments were sulfosulfuron at 18, 20.25 and 22.5 g a.i. ha -1 , metsulfuron-methyl plus sulfosulfuron at 28, 32 and 36 g a.i. ha -1 , mesosulfuron-methyl plus iodosulfuron-methyl at 14.4, 18 and 21.6 g a.i. ha -1 , iodosulfuron plus mesosulfuron at 18, 24 and 30 g a.i. ha -1 and two weedy and weed free checks. Compared with the weedy check, application of herbicides in both growing seasons reduced weed biomass and increased wheat biological and grain yield. Among herbicide treatments, metsulfuron-methyl plus sulfosulfuron at 36 g a.i. ha -1 reduced weed dry matter by 98. 6% and 97.55% in 2011-2012 and 2012-2013, respectively, and the lowest weed dry matter was observed with this treatment. In both years, maximum wheat biological yield was obtained in weed free check that was not significantly different from metsulfuron-methyl plus sulfosulfuron at 36 g a.i. ha -1 . The highest wheat grain yield was obtained with metsulfuron-methyl plus sulfosulfuron at 36 g a.i. ha -1 .

Haemonchosis, caused by the hematophagous nematode Haemonchus contortus, remains a major challenge to ruminant health and production worldwide. This review explores the epidemiology, diagnosis and control strategies for haemonchosis, emphasizing the growing threat of anthelmintic resistance. The parasite thrives in warm, humid climates, with transmission dynamics significantly influenced by regional environmental conditions. Epidemiological investigations, including tracer animal studies, fecal sample analyses and slaughterhouse surveys, provide crucial insights into parasite burden and infection trends. However, seasonal variations and host immunity complicate accurate assessments. Climate plays a pivotal role in the persistence and transmission of H. contortus. In tropical and subtropical regions, continuous parasite transmission occurs, whereas hypobiosis ensures survival in harsh climates. Understanding these regional infection patterns aids in designing effective parasite control programs. The increasing prevalence of anthelmintic resistance, characterized by genetic mutations in -tubulin, nicotinic acetylcholine receptors and glutamate-gated chloride channels, necessitates alternative control measures. The failure of benzimidazoles, imidazothiazoles and macrocyclic lactones due to resistance highlights the urgency of sustainable strategies, including targeted selective treatment, pasture management and genetic selection for parasite-resistant breeds. Advancements in diagnostic methodologies, such as molecular techniques (PCR, LAMP) and immunodiagnostics, have enhanced the precision of haemonchosis detection. Traditional approaches, including fecal egg count, hematological parameters and post-mortem findings, remain valuable but require integration with modern diagnostics for improved accuracy. This review underscores the need for a multifaceted approach combining epidemiological surveillance, innovative diagnostics and integrated parasite management strategies to mitigate the economic and health impacts of haemonchosis in grazing ruminants.

Spontaneous alginate-producing (muc) variants were isolated from strains of Pseudomonas Jluorescens, P. putida and P. mendocina at a frequency of 1 in lo8 by selecting for carbenicillin resistance. The infrared spectrum of the bacterial exopoly saccharide was typical of an acetylated alginate similar to that previously described in Azotobacter vinelandii and in mucoid variants of P. aeruginosa. Mucoid variants were not isolated from P. stutzeri, P. pseudoalcaligenes, P. testosteroni, P. diminuta, P. acidovorans, P. cepacia or P. maltophilia. Only two species of bacteria, Azotobacter vinelandii (Gorin & Spencer, 1966) and Pseudomonas aeruginosa , are known to produce alginic acid, a ( 1 4)-linked linear copolymer of p-D-mannuronic and a-L-guluronic acids. Alginate production in P. aeruginosa is restricted to mucoid variants which are rarely encountered except in association with chronic pulmonary infection in patients with cystic fibrosis (Doggett, 1969). We have previously reported that mucoid mutants of P. aeruginosa can be isolated in vitro from wild-type, non-mucoid strains by selecting for carbenicillin resistance or resistance to a virulent phage . Mutations responsible for this change in phenotype can be mapped on the chromosome (Fyfe & Govan, 1980). This evidence suggested that wild-type, non-mucoid strains of P. aeruginosa carry the genetic information necessary for alginate production but it is normally repressed. The aim of the present study was to determine whether alginate-producing mutants occur in other species of Pseudomonas. We report for the first time the isolation of mutant strains of P. putida, P. Jluorescens and P. mendocina producing an alginate-like exopolysaccharide similar to that obtained from A. vinelandii and mucoid P. aeruginosa.

Worldwide, the cultivation of Cocos nucifera is cultivated in 92 countries, Mexico occupies ninth place, with the state of Guerrero being the first place nationally. However, its economic production is affected by pests and diseases, one of them is Raoiella indica, its only means of control being chemical insecticides that contribute to the environmental crisis. In this work, the concentration-lethality of 3 biological and two chemical extracts on R. indica was compared, as well as the LC 50 for each of the products. These products were applied by spraying, using the Burgerjon tower, directly on adult females of R. indica, placed on leaflet discs 5 cm in diameter. Mortality was recorded at 24, 48 and 72 hours. At all these times, Abamectin showed the lowest LC 50 values, which means the highest toxicity; In decreasing order of toxicity, Asphix, Saf-T-Side, Spiridiclofen and Biodie followed. The LC 50 of Neem Higuer, Neem Canela and Bio-Piretrin were not estimated because in the preliminary bioassays it was observed that they have minimal toxicity. The use of Asphix is preferably recommended for the control of R. indica, due to its low price compared to Abamectin, as well as its status as a biorational product.

Herbicides are much more than just chemicals to control weed plants, and they can also influence the ecosystems. So, it is necessary to choose new herbicide with low active ingredients in order to reduce environmental issues, as well as control weed plants. A field experiment was conducted to evaluate the efficiency and to compare two herbicides containing similar active ingredients, Chevalier WG and Atlantis OD, as they contain metsufuron-methyl and iodosufuron-methyl sodium at different rates. Chevalier contains 30 g/l of each active ingredient; whilst Atlantis OD has 10 g/l of metsulfuron-methyl and 2 g/l of iodosufuron-methyl sodium. The results showed that all treatments significantly were active to control the weeds in both wheat varieties. Narrow-leaves Weeds density was decreased density 91.70 and 94.14% by Atlantis OD minus 25% in Aras and Simeto respectively, and the yield of Aras was increased 255%. In accordance with the results, a herbicide with low active ingredients, ...

Weeds represent one of the most important biotic threats to agricultural plant health, and the potential global impact of weeds on crop yields is similar to that of all other pests (animal pests and pathogens) combined. Canola is the most-grown crop in Canada based on seeded area and generates on average Can$29.9 billion in economic activity each year. The objective of this report, sponsored by the Weed Science Society of America Weed Loss Committee, was to provide an updated estimate of potential yield and monetary losses due to weed interference in spring canola grown in Canada and the United States. Quantitative yield data from field experiments were provided by researchers and weed science professionals in the northern Great Plains region; the major canola-producing area of North America. Overall, 89 yield loss estimates were compiled, covering the 18-yr period from 2003 to 2020. Average canola yield losses due to weed interference in Alberta, Saskatchewan, Manitoba, and North Dakota were 35%, 30%, 18%, and 28%, respectively. Potential yield losses weighted by canola harvested area averaged 30%, 28%, and 30% for Canada, the United States, and both countries combined, respectively. Therefore, unfettered weed interference in spring canola represents a potential monetary loss of Can$2.21 billion, $0.16 billion, and $2.37 billion for farmers in Canada, the United States, and both countries combined. The realization of such losses could manifest through continued selection for herbicide-resistant weeds, indicating the critical need for canola farmers to diversify resistance selection pressures by implementing proactive integrated weed management programs.

Termites' attack has been a major problem for wooden structures and buildings. The severity of termites' attack on the AAUA campus area using Triplochiton scleroxylon wood as bait was examined. Identification of prevalent termite species as well as the soil's physical properties were studied in twenty sampled locations. Defect-free wood samples of Triplochiton scleroxylon dimensioned 35 × 35 × 450mm according to ASTM D3345-17 (2017) were buried halfway in the soil and exposed to termite attacks for 12 weeks (3 months) in an established timber graveyard at the locations. A weekly visual assessment of the stakes was done in accordance with the ASTM D 3345 rating scale and a gravimetric weight loss assessment was carried out after the period of exposure. Data obtained were used to produce termites severity probability map of the campus area was prepared using ArcGIS software and following the USDA standard color codes. Six termites species identified were: Ancistrotermes cavithorax

This study was conducted to test five substrates (whole rice, broken rice, dovme, wheat and burghul) for the mass production of Beauveria bassiana isolate 5-4, known to be affective against stored-cereal pests. A solid-state fermentation technique was used, and amount of product, number of conidia, germination, hydrophobicity and thermotolerance of conidia, and their virulence on Rhyzopertha dominica adults were used to evaluate the success of substrates. For production, 100 g of a substrate was used in a polypropylene bag. After sterilization and inoculation, the bags were sealed and incubated for 14 days at 25ºC. Hydrophobicity was assessed using the aqueous-solvent partitioning method with PM buffer, and liquid paraffin as two phases. Thermotolerance tests were conducted by exposing conidia to 35, 40 and 45°C for 15, 30 and 60 minutes. In virulence test, adults were released into 40 gr wheat mixed with conidia and kept at 25oC and 65% relative humidity in darkness for 14 days. Th...

In this paper we consider the adoption of pest management technologies by farmers in UK cereal crop systems. While for the majority of UK farmers chemical control of pest outbreaks remains important, there are a range of non-chemical approaches and management practices that can be used to control pest populations. However, few of these alternatives produce levels of control that compare with chemical use in isolation. In this paper we consider the determinants of adoption of different combinations of individual pest management technologies. Based on survey data we first construct sets of pest management technologies before modelling the decision problem as a multiple adoption process to examine variation in the adoption of these technology sets. Our results indicate that the choice of technologies adopted can be related to specific aspects of farm level activity and type. The authors acknowledge the financial support provided by the Rural Economy and Land Use Grant . We would also like to thank the farmers who participated in the pilot study as well as Rothamsted Research for granting us access to these farmers and to all respondents of the main survey itself. We also acknowledge the help of the HGCA for allowing us the use of their mailing database to undertake the main survey.

Studies were conducted at Agricultural Research Farm, Banaras Hindu University, Varanasi during Kharif 2010 and 2011 to know the efficacy of some new molecule insecticides (azadirachtin, Bt, endosulfan 35% EC, thiodicarb 75% WP, spinosad 45% SC, lambda cyhalothrin 5% EC, indoxacarb 14.5% SC, profenophos 50% EC and acetamiprid 20% SP) against spotted pod borer, Maruca vitrata (Geyer) on mungbean. The spinosad 45% SC and indoxacarb 14.5 % SC were the most effective treatments and significantly superior to other treatments with 80.7 and 79.2 per cent larval reduction over control. The least effective treatment was acetamiprid 20%SP, followed by azadirachtin with 38.8 and 44.9 per cent reduction in larval population over control. The maximum yield was recorded in treatment indoxacarb 14.5%SC (11.8q/ha) followed by spinosad 45%SC (11.1q/ha) which were at par with each other. While lowest yield was recorded in azadirachtin (9.7q/ha). • The spotted pod borer, Maruca vitrata (Geyer) is serious pest of grain legume crops including mungbean, urdbean, pigeonpea and common beans. • The spinosad 45% SC and indoxacarb 14.5 % SC were the most effective treatments and significantly superior to other treatments with 80.7 and 79.2 per cent larval reduction over control. • The least effective treatment was acetamiprid 20% SP, followed by azadirachtin with 38.8 and 44.9 per cent reduction in larval population over control. • The maximum yield was recorded in treatment indoxacarb 14.5% SC (11.8q/ha) followed by spinosad 45%SC (11.1q/ha) which were at par with each other.

Efficiency of insecticides, applied as seed treatment and in plant pulverization in the control of green belly stink bug, Dichelops melacanthus (Dallas) (Hemiptera: Pentatomidae), in corn crop ABSTRACT -The efficiency of the insecticide thiamethoxam applied as seed treatment (210 g i.a./100 kg), the mixture thiamethoxam + lambda-cyhalothrin (16.5+33 and 33+66 g i.a./ha) applied as plant pulverization and the association of both treatments in the control of Dichelops melacanthus adults on corn crop were evaluated. The experiment was carried out at greenhouse and field conditions, with five chemical treatments and one control treatment (without insecticide). The seed treatment was done one day before field sowing. Ten days after the complete plant emergence (in greenhouse and field) the pulverization was done with thiamethoxam+lambda-cyhalothrin. Then, adults of green belly stink bug were liberated to feed on corn plants, being used screen cages for contention of the insects. The survival of adults of D. melacanthus was significantly influenced by chemical treatments applied both on seeds and in corn plant pulverization either at greenhouse or at field conditions. At greenhouse conditions, it was observed better control of adults when thiamethoxam was applied on corn seeds, independently if the corn plants were sprayed or not with the mixture thiamethoxam+lambda-cyhalothrin. However, at field conditions, the mixture thiamethoxam+lambda-cyhalothrin sprayed on corn plant was more efficient in the control of green belly stink bug than tiametoxam applied on seeds.

The analysis of hybrid frequency in mixed natural populations of R. obtusifolius and R. crispus on the level of the seed and the adult population and the analysis of Fl fertility and the F2 generation leads to the following conclusions: 1. The variation in hybrid frequency found in the comparison of the three different sites near Heidelberg examined, between the individual seed parents and between the two parent species from the three sites cannot be correlated with the overall composition of the adult population and its spatial structure in most cases. The extent of hybridization rather depends on the circumstances found by the individual plant during its flowering period (e.g. climatic conditions, flowering period of neighbouring individuals). Differences in the hybridization behaviour of R. obtusifolius and R. crispus can partly be explained with their differing flowering period. 2. Changes in the proportional representation of R. obtusifolius, R. crispus and R. X pratensis from the seed to the adult population are suggested to depend on the different degree of seed dormancy in the three taxa and the hybrid vigour of R. X pratensis. 3. Introgressive hybridization between R. obtusifolius and R. crispus can take place, but is not likely to be a very frequent event. In the populations examined, the dominant direction of gene flow will be from R. crispus into R. obtusifolius. 4. Hybridization between R. obtusifolius and R. crispus has a detrimental effect on both parent species through the loss of progeny in form of hybrid seeds, competition between the parent species and the hybrid in the adult population and probably through the loss of seed dormancy in at least R. obtusifolius resulting from gene flow into this species.

Flooding is known to mobilise soil phosphorus (P). However, it is still not clear how climate change-driven extended periods of soil drying followed by flooding will affect soil-P dynamics. We tested the hypothesis under laboratory conditions that soil antecedent conditions (moist/dry) determine the amount of P mobilised upon flooding. A series of controlled laboratory experiments were carried out by flooding samples of two contrasting soils, which had each been either dried (40°C for 10-days) or kept at field moisture conditions (25% moisture content). Flooding was simulated by maintaining a 10-cm water-column depth in mesocosms. Periodically collected water samples were analysed for dissolved reactive P (DRP), total dissolved P (TDP) and dissolved unreactive P (DUP). The onset of flooding significantly (p < 0.001) increased dissolved concentrations of all forms of P. The release of TDP coincided with a reduction in redox potential, suggesting reductive dissolution of P bearing Fe/Mn minerals as indicated by a significant positive correlation between TDP and dissolved Fe (r = 0.430, p < 0.001) and TDP and dissolved Mn (r = 0.622, p < 0.001). Flooding of the dried soils caused a significantly greater increase in the dissolved P concentrations of all forms of P relative to their moist-flooded counterparts. This could be due to a combination of factors which are associated with soil drying and flooding. The Crediton dry-flooded (CDF) soils released higher concentrations of DRP upon flooding (e.g., 0.14 mg P L -1 on day 1 after flooding) perhaps due to its higher concentrations of water-and NaHCO3-extractable P than the Hallsworth dry-flooded (HDF) soil (0.03 mg P L -1 on day 1 after flooding). However, most of the P in the water column of the dry-flooded soils was unreactive, with the HDF soil releasing higher concentrations of DUP, likely due to its higher organic matter and microbial biomass-P contents. The results suggest that flooding of dried soils has greater potential to enhance mobilisation of soil-P than flooding of moist soils and thus has potential implications for soil fertility and surface water quality.

| Citrus greening (CG) or huanglongbing (HLB) is the major cause of citrus decline. The disease is currently prevailing in all districts of Punjab and posing severe threat to citrus production and export. The current research was designed with two objectives; (1) to study the population dynamics of Diaphorina citri, the vector of CG, and (2) to record the incidence of CG in different citrus growing areas of Punjab and estimation of losses caused by this disease. To study the dynamics of Asian citrus psyllid (ACP), a comprehensive survey of kinnow (Citrus reticulate cv. kinnow), musambi (Citrus sinensis cv. musambi) and feutrell's early (Citrus reticulate cv. feutrell's early) orchards was conducted in tehsil Sargodha during 2017 and 2018. Correlation and regression analysis were used to determine the relationship of ACP with CG, and the relationship of environmental factors with ACP. Surveys were conducted to record the incidence of CG and estimate the yield losses caused by it. The study of population dynamics of ACP revealed that ACP population was higher between 7 th to 14 th April and 11 th to 18 th September, during 2017 and 2018. While, there was less ACP population between February 10 th to 2 nd March and 10 th July to 30 th July, during 2017 and 2018, respectively. There was significant and positive correlation between ACP population and CG on kinnow, musambi and feutrell's early cultivars. Maximum and minimum temperatures and rainfall also showed positive and significant correlation with CG, while relative humidity showed not significant correlation with CG. During current study, maximum temperature, minimum temperature and rainfall explained maximum, i.e., 79, 76 and 83% variability in ACP population, respectively. The incidence of CG was observed higher (45%) in Faisalabad while lower (21.67%) in Multan. Similarly, yield losses due to CG were recorded maximum (33.5%) in Faisalabad and lowest (15.5%) in Multan districts. The current findings will help in the effective control of CG in Punjab by the in time management of its vector. Statement | The epidemiology of D. citri and yield losses caused by CG have been studied first time in citrus belt of Punjab, Pakistan, during this research.