scholarly journals Ecology of Fungus Gnats (Bradysia spp.) in Greenhouse Production Systems Associated with Disease-Interactions and Alternative Management Strategies

Insects ◽  
2015 ◽  
Vol 6 (2) ◽  
pp. 325-332 ◽  
Author(s):  
Raymond Cloyd
2022 ◽  
Vol 52 (7) ◽  
Author(s):  
Adriane da Fonseca Duarte ◽  
Juliano Lessa Pinto Duarte ◽  
Patrícia da Silva Grinberg ◽  
Uemerson Silva da Cunha

ABSTRACT: Soilless cultivation of strawberry is in expansion in Brazil due to factors like the reduction of phytosanitary problems and the possibility of extending the crop period, as well as the ergonometric facility for management of the culture. However, black fungus gnats (Sciaridae, Diptera) are ubiquitous pests in the greenhouse production system, causing direct and indirect damage to plants. ThIS study evaluated the occurrence of black fungus gnats species in semi-hydroponic cultivation of strawberry and to identify the species, as well as to describe the symptoms in infested plants. The research was developed in commercial productions of strawberry, in five municipalities (Arroio do Padre, Canguçu, Capão do Leão, Pelotas and Turuçu) during July to December 2017, where adult samples were collected twice a month, with petri dish traps containing water and neutral detergent placed inside the greenhouses between the plants. A total of 2030 adult gnats belonging to two species were collected. Bradysia aff. impatiens, accounted with 90.79% of the total, and Bradysia aff. ocellaris, accounted with 9.21%. In order to assist the correct determination of species, males of both species were identified and illustrated. With respect to the symptoms observed during the research, it was possible to verify since the wilted crown of plants to the death of plants, which were confirmed by the presence of larvae in the root system. As the occurrence of these insects is recent in strawberry, there is no pesticide registered in Brazil, so management strategies (cultural, physical, and sanitary) also are discussed.


2019 ◽  
Vol 446 (1-2) ◽  
pp. 163-177 ◽  
Author(s):  
Arlete S. Barneze ◽  
Jeanette Whitaker ◽  
Niall P. McNamara ◽  
Nicholas J. Ostle

Abstract Aims Grasslands are important agricultural production systems, where ecosystem functioning is affected by land management practices. Grass-legume mixtures are commonly cultivated to increase grassland productivity while reducing the need for nitrogen (N) fertiliser. However, little is known about the effect of this increase in productivity on greenhouse gas (GHG) emissions in grass-legume mixtures. The aim of this study was to investigate interactions between the proportion of legumes in grass-legume mixtures and N-fertiliser addition on productivity and GHG emissions. We tested the hypotheses that an increase in the relative proportion of legumes would increase plant productivity and decrease GHG emissions, and the magnitude of these effects would be reduced by N-fertiliser addition. Methods This was tested in a controlled environment mesocosm experiment with one grass and one legume species grown in mixtures in different proportions, with or without N-fertiliser. The effects on N cycling processes were assessed by measurement of above- and below-ground biomass, shoot N uptake, soil physico-chemical properties and GHG emissions. Results Above-ground productivity and shoot N uptake were greater in legume-grass mixtures compared to grass or legume monocultures, in fertilised and unfertilised soils. However, we found no effect of legume proportion on N2O emissions, total soil N or mineral-N in fertilised or unfertilised soils. Conclusions This study shows that the inclusion of legumes in grass-legume mixtures positively affected productivity, however N cycle were in the short-term unaffected and mainly affected by nitrogen fertilisation. Legumes can be used in grassland management strategies to mitigate climate change by reducing crop demand for N-fertilisers.


2006 ◽  
Vol 7 (1) ◽  
pp. 29
Author(s):  
S. N. Rampersad

Tomato production in Trinidad has suffered considerable losses in yield and fruit quality due to infections of hitherto surmised etiology. In order to develop strategies for controlling viral diseases in tomato, the relative distribution and incidence of seven viruses that commonly infect tomato were determined. Of the 362 samples tested, Potato yellow mosaic Trinidad virus (PYMTV) was found in every farm except two and was present at relatively high incidence throughout the country. Tobacco mosaic virus (TMV) and Tobacco etch virus (TEV) were found in fewer farms and at lower incidences while the other viruses were absent. Single infections of either virus were more common than double infections and multiple infections were rare but present. The results indicated that PYMTV is the predominant and most important viral pathogen in tomato production systems in Trinidad; however, begomovirus disease management strategies will also have to accommodate controls Accepted for publication 10 January 2006. Published 9 March 2006.


2015 ◽  
pp. 45-52
Author(s):  
C. Poncet ◽  
C. Bresch ◽  
H. Fatnassi ◽  
L. Mailleret ◽  
A. Bout ◽  
...  

Geoderma ◽  
2021 ◽  
Vol 385 ◽  
pp. 114899
Author(s):  
Ya'nan Fan ◽  
Yanxia Zhang ◽  
Zhikun Chen ◽  
Xinkai Wang ◽  
Biao Huang

2018 ◽  
Vol 37 (3) ◽  
pp. 210-218
Author(s):  
Cansu Demir ◽  
Ülkü Yetiş ◽  
Kahraman Ünlü

Thermal power plants are of great environmental importance in terms of the huge amounts of wastes that they produce. Although there are process-wise differences among these energy production systems, they all depend on the logic of burning out a fuel and obtaining thermal energy to rotate the turbines. Depending on the process modification and the type of fuel burned, the wastes produced in each step of the overall process may change. In this study, the most expected process and non-process wastes stemming from different power generation processes have been identified and given their European Waste Codes. Giving priority to the waste minimization options for the most problematic wastes from thermal power plants, waste management strategies have been defined. In addition, by using the data collected from site visits, from the literature and provided by the Turkish Republic Ministry of Environment and Urbanization, waste generation factor ranges expressed in terms of kilogram of waste per energy produced annually (kg/MWh) have been estimated. As a result, the highest generation was found to be in fly ash (24–63 for imported coal, 200–270 for native coal), bottom ash (1.3–6 for imported coal, 42–87 for native coal) and the desulfurization wastes (7.3–32) produced in coal combustion power plants. The estimated waste generation factors carry an important role in that they aid the authorities to monitor the production wastes declared by the industries.


2014 ◽  
Vol 65 (7) ◽  
pp. 583 ◽  
Author(s):  
J. A. Kirkegaard ◽  
J. R. Hunt ◽  
T. M. McBeath ◽  
J. M. Lilley ◽  
A. Moore ◽  
...  

Improving the water-limited yield of dryland crops and farming systems has been an underpinning objective of research within the Australian grains industry since the concept was defined in the 1970s. Recent slowing in productivity growth has stimulated a search for new sources of improvement, but few previous research investments have been targeted on a national scale. In 2008, the Australian grains industry established the 5-year, AU$17.6 million, Water Use Efficiency (WUE) Initiative, which challenged growers and researchers to lift WUE of grain-based production systems by 10%. Sixteen regional grower research teams distributed across southern Australia (300–700 mm annual rainfall) proposed a range of agronomic management strategies to improve water-limited productivity. A coordinating project involving a team of agronomists, plant physiologists, soil scientists and system modellers was funded to provide consistent understanding and benchmarking of water-limited yield, experimental advice and assistance, integrating system science and modelling, and to play an integration and communication role. The 16 diverse regional project activities were organised into four themes related to the type of innovation pursued (integrating break-crops, managing summer fallows, managing in-season water-use, managing variable and constraining soils), and the important interactions between these at the farm-scale were explored and emphasised. At annual meetings, the teams compared the impacts of various management strategies across different regions, and the interactions from management combinations. Simulation studies provided predictions of both a priori outcomes that were tested experimentally and extrapolation of results across sites, seasons and up to the whole-farm scale. We demonstrated experimentally that potential exists to improve water productivity at paddock scale by levels well above the 10% target by better summer weed control (37–140%), inclusion of break crops (16–83%), earlier sowing of appropriate varieties (21–33%) and matching N supply to soil type (91% on deep sands). Capturing synergies from combinations of pre- and in-crop management could increase wheat yield at farm scale by 11–47%, and significant on-farm validation and adoption of some innovations has occurred during the Initiative. An ex post economic analysis of the Initiative estimated a benefit : cost ratio of 3.7 : 1, and an internal return on investment of 18.5%. We briefly review the structure and operation of the initiative and summarise some of the key strategies that emerged to improve WUE at paddock and farm-scale.


2020 ◽  
Vol 11 (1) ◽  
pp. 054
Author(s):  
José Antonio De Miranda Lammoglia ◽  
Nilson Brandalise ◽  
Cecilia Toledo Hernandez

The scenario of global competitiveness demands more and more of the organizations the search for continuous improvement. For survival, in the face of adverse market conditions, modern production management strategies are essential to make production processes increasingly efficient, lean and sustainable, minimizing losses in their production systems. In this sense, when thinking about changes in production lines, in search of improvements in their process, criteria that provide Benefits, Opportunities, Costs and Risks (BOCR) should be considered. In this way, managers and executives should rely on tools and methods that allow them to guide their decisions in a clear way. The objective of this work is to apply a method of Decision Making with Multiple Criteria to the alternatives of investment projects in production lines in Lean Manufacturing concept. As a general result, it was possible to observe the applicability of the AHP BOCR method for the decision-making case involving several criteria and subcriteria for choosing the Lean investment project in the steel environment, the preferred alternative being the discontinuity of the production line 1 and the absorption of their respective production volume by production lines 2 and 3 through investments in them.


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