Developing and communicating strategies for controlling virus diseases in vegetable cucurbit crops

Virus diseases cause serious yield and quality losses in field grown cucurbit crops worldwide. In Australia, the main viruses of cucurbits are Papaya ringspot virus (PRSV), Squash mosaic virus (SqMV), Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV). Plants infected early have severely distorted fruit. High infection incidences, of ZYMV and PRSV in crops cause losses of marketable fruit of up to 100% and infected crops are often abandoned. Two new alternative hosts of ZYMV were identified, the native cucurbit Cucumis maderaspatanus and wild legume Rhyncosia minima. No new alternative hosts of PRSV, SqMV or WMV were found in Western Australia or Queensland. Seed transmission of ZYMV (0.7%) was found in seedlings grown from ZYMV-infected fruit of zucchini but not of pumpkin. None was detected with PRSV or SqMV in zucchini or pumpkin seedlings, respectively. ZYMV spread to pumpkins by aphids was greater downwind than upwind of a virus source. Delaying sowing by 2 weeks decreased ZYMV spread. Millet non-host barriers between pumpkin plantings slowed ZYMV infection. Host resistance gene (zym) in cucumber cultivars was effective against ZYMV. Pumpkin cultivars with resistance gene (Zym) became infected under high virus pressure but leaf symptoms were milder and infected plants higher yielding with more market-acceptable fruit than those without Zym. Most zucchini cultivars with Zym developed severe leaf and fruit symptoms. ZYMV, PRSV, WMV and SqMV spread readily from infected to healthy cucurbit plants by direct leaf contact. ZYMV survives and remains infective on diverse surfaces for up to 6 hours but can be inactivated by some disinfectants. Phylogenetic analysis indicates at least three separate introductions of ZYMV into Australia, with new introductions rarely occurring. ZYMV isolates clustered into three groups according to collection location i) Kununurra, ii) Northern Territory and iii) Carnarvon, Qld and Vic. A multiplex Real-Time PCR was developed which distinguished between the three groups of Australian isolates. Integrated disease management (IDM) strategies for virus diseases of vegetable cucurbit crops grown in the field were improved incorporating the new information gathered. These strategies are aimed at causing using minimal extra expense, labour demands and disruption to normal practices.

Strategic banana tissue culture industry development and biosecurity act

Application and development of activities based on in vitro technologies delivering research, industry development and biosecurity activities to sustain and improve the Australian banana industry.

ACIAR Improving soil health in support of sustainable development in the Pacific

The proposed project focuses on developing research-based indicators that growers and extensionists can use to assess soil health status (including key chemical, physical and biological variables), as well as extension approaches to communicate soil health.

TU10025 Erosion control - turf research and development facility

The aim of this project is to construct a large-scale erosion control education and demonstration facility at Redland Research Station. This will be done in collaboration with the Australian turf industry (as members of the steering committee) and consultant researcher Dr Rob Loch (project partner). The project will employ a part-time industry development officer (IDO) for Turf Australia to increase engagement with the project by the target audience. The project’s main strategy is to extend the research results from HAL funded project Optimising Turf Use to Minimise Soil Erosion on Construction Sites TU08033 so that the maximum return on investment can be derived for the turf levy payers and HAL from that study.

Water Use Efficiency Investment for Healthy Headwaters

Agri-Science Queensland to provide a range of extension services to improve water use efficiency in irrigated agriculture in the Queensland Murray Darling Basin and support the implementation of the Healthy Headwaters On-farm Water Use Efficiency program.

Participatory adaptation and mitigation strategies for climate change on mixed farms

The project uses participatory methods to engage primary producers and advisers in central Queensland, southern Queensland, and north east New South Wales on-farm trials and demonstrations to adapt mixed farming systems to changed climate conditions. The focus is adaptation to climate change but will support abatement of greenhouse gas emissions by building soil carbon, better managing soil nitrogen and soil organic carbon. Data will be collected and integrated with data from Round 1 of the Climate Change Research Program to extend industry understanding beyond a general awareness of ‘climate change’. Nitrous oxide and soil carbon data will help farmers/advisers understand the implications of climate change and develop adaptation strategies for a more sustainable, climate sensitive future.

Diagnostic Agronomy

Develop and implement a diagnostic framework designed to help advisors and farmers identify the causes of poor crop performance and implement appropriate remedial measures.

ACIAR Scoping study for Improved food security and livelihoods in rural Zimbabwe

A short project to provide input to planning a project aimed at improving food security and rural livelihoods in Zimbabwe.

Driving better vegetable irrigation through profitable practice change

The availability and quality of irrigation water has become an issue limiting productivity in many Australian vegetable regions. Production is also under competitive pressure from supply chain forces. Producers look to new technologies, including changing irrigation infrastructure, exploring new water sources, and more complex irrigation management, to survive these stresses. Often there is little objective information investigating which improvements could improve outcomes for vegetable producers, and external communities (e.g. meeting NRM targets). This has led to investment in inappropriate technologies, and costly repetition of errors, as business independently discover the worth of technologies by personal experience. In our project, we investigated technology improvements for vegetable irrigation. Through engagement with industry and other researchers, we identified technologies most applicable to growers, particularly those that addressed priority issues. We developed analytical tools for ‘what if’ scenario testing of technologies. We conducted nine detailed experiments in the Lockyer Valley and Riverina vegetable growing districts, as well as case studies on grower properties in southern Queensland. We investigated root zone monitoring tools (FullStop™ wetting front detectors and Soil Solution Extraction Tubes - SSET), drip system layout, fertigation equipment, and altering planting arrangements. Our project team developed and validated models for broccoli, sweet corn, green beans and lettuce, and spreadsheets for evaluating economic risks associated with new technologies. We presented project outcomes at over 100 extension events, including irrigation showcases, conferences, field days, farm walks and workshops. The FullStops™ were excellent for monitoring root zone conditions (EC, nitrate levels), and managing irrigation with poor quality water. They were easier to interpret than the SSET. The SSET were simpler to install, but required wet soil to be reliable. SSET were an option for monitoring deeper soil zones, unsuitable for FullStop™ installations. Because these root zone tools require expertise, and are labour intensive, we recommend they be used to address specific problems, or as a periodic auditing strategy, not for routine monitoring. In our research, we routinely found high residual N in horticultural soils, with subsequently little crop yield response to additional nitrogen fertiliser. With improved irrigation efficiency (and less leaching), it may be timely to re-examine nitrogen budgets and recommendations for vegetable crops. Where the drip irrigation tube was located close to the crop row (i.e. within 5-8 cm), management of irrigation was easier. It improved nitrogen uptake, water use efficiency, and reduced the risk of poor crop performance through moisture stress, particularly in the early crop establishment phases. Close proximity of the drip tube to the crop row gives the producer more options for managing salty water, and more flexibility in taking risks with forecast rain. In many vegetable crops, proximate drip systems may not be cost-effective. The next best alternative is to push crop rows closer to the drip tube (leading to an asymmetric row structure). The vegetable crop models are good at predicting crop phenology (development stages, time to harvest), input use (water, fertiliser), environmental impacts (nutrient, salt movement) and total yields. The two immediate applications for the models are understanding/predicting/manipulating harvest dates and nitrogen movements in vegetable cropping systems. From the economic tools, the major influences on accumulated profit are price and yield. In doing ‘what if’ analyses, it is very important to be as accurate as possible in ascertaining what the assumed yield and price ranges are. In most vegetable production systems, lowering the required inputs (e.g. irrigation requirement, fertiliser requirement) is unlikely to have a major influence on accumulated profit. However, if a resource is constraining (e.g. available irrigation water), it is usually most profitable to maximise return per unit of that resource.

Relación entre los estilos de liderazgo y los niveles de resiliencia de los subordinados

El presente documento hace un análisis de la influencia que ejercen los diferentes tipos de liderazgo, carismático y transaccional, de un directivo de una organización sobre los subordinados de la misma, que a su vez afecta positiva o negativamente el nivel de resiliencia de los mismos. De la misma forma, se ha identificado la relación que existe entre el nivel de resiliencia de los subordinados de una organización y el cumplimiento de objetivos corporativos de la misma. Todo lo anterior se justifica en la economía globalizada de la que ahora hacemos parte que obliga a las empresas a generar nuevas estrategias de competitividad dentro de ambientes turbulentos y cambiantes donde, el desarrollar y motivar el recurso humano de la organización toma importancia para la ejecución exitosa de estrategias diferenciales.

Cropping systems, carbon sequestration and erosion in Brazil, a review

Soils represent a large carbon pool, approximately 1500 Gt, which is equivalent to almost three times the quantity stored in terrestrial biomass and twice the amount stored in the atmosphere. Any modification of land use or land management can induce variations in soil carbon stocks, even in agricultural systems that are perceived to be in a steady state. Tillage practices often induce soil aerobic conditions that are favourable to microbial activity and may lead to a degradation of soil structure. As a result, mineralisation of soil organic matter increases in the long term. The adoption of no-tillage systems and the maintenance of a permanent vegetation cover using Direct seeding Mulch-based Cropping system or DMC, may increase carbon levels in the topsoil. In Brazil, no-tillage practices (mainly DMC), were introduced approximately 30 years ago in the south in the Parana state, primarily as a means of reducing erosion. Subsequently, research has begun to study the management of the crop waste products and their effects on soil fertility, either in terms of phosphorus management, as a means of controlling soil acidity, or determining how manures can be applied in a more localised manner. The spread of no-till in Brazil has involved a large amount of extension work. The area under no-tillage is still increasing in the centre and north of the country and currently occupies ca. 20 million hectares, covering a diversity of environmental conditions, cropping systems and management practices. Most studies of Brazilian soils give rates of carbon storage in the top 40 cm of the soil of 0.4 to 1.7 t C ha(-1) per year, with the highest rates in the Cerrado region. However, caution must be taken when analysing DMC systems in terms of carbon sequestration. Comparisons should include changes in trace gas fluxes and should not be limited to a consideration of carbon storage in the soil alone if the full implications for global warming are to be assessed.

Contribuição da educação nutricional junto a um grupo de isodosos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Agricultura familiar em duas microrregiões do Noroeste do Estado de São Paulo: uma análise comparativa entre as explorações agropecuárias e as políticas públicas dirigidas ao segmento

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Dora Dee Walker Papers - Accession 104 - M44 (59)

The Dora Dee Walker Papers consist of biographical sketches and data sheets, a letter, photographs, a newspaper clipping and a copy of the history of extension work in Allendale County, all relating to Dora Walker, pioneering State leader in extension work in South Carolina.

Perfil de los extensionistas rurales argentinos del sistema público

Pese la importancia de la extensión rural en toda estrategia orientada el desarrollo de los sectores de productores rurales pequeños y medianos, no existen en la Argentina trabajos académicos que reconstruyan de manera completa y sistemática el perfil de quienes trabajan en el país en extensión rural. Por esta razón, se realizó una investigación cuantitativa descriptiva de carácter transversal que permitió reconstruir el perfil de los extensionistas rurales que trabajan en el sistema de extensión público argentino. Para este fin se realizó una encuesta (enviada vía email) a extensionistas del INTA, ProHuerta y de la Subsecretaría de Agricultura Familiar. Los resultados de esta investigación permitieron aportar, a partir del uso de herramientas estadísticas, a la descripción del perfil de los extensionistas rurales que trabajan en la Argentina, así como a la del perfil diferencial de hombres y mujeres y de quienes trabajan en las diferentes instituciones