Fusarium: Historical and Continued Importance

Historically, Fusarium has been important because: (i) taxonomy of Fusarium species has been a controversial issue, (ii) Fusarium species are among the most important plant pathogens in the world, and (iii) many Fusarium species produce mycotoxins that cause animal and human diseases. The genus Fusarium was introduced by Link in 1809. “Die Fusarien” was published by Wollenweber and Reinking in 1935, described 65 species, 55 varieties, and 22 forms of Fusarium. In 1945, Snyder and Hansen reduced number of species of Fusarium to nine. In 1990s, the application of phylogenic species concept based on the DNA sequencing resulted in introducing new species of Fusarium that cannot be distinguished morphologically. In 2006, Leslie and Summerell integrated the morphological, biological, and phylogenic species concepts and published “The Fusarium Laboratory Manual,” which provides details of identification of 70 Fusarium species. Although considerable research studies on Fusarium have been accomplished in the past 200 years, yet Fusarium diseases continue to be among the most important plant diseases. Fusarium fungi are the most widespread in cereal-growing areas of the world and produce a diversity of mycotoxins, including zearalenone, fumonisin, moniliformin, and trichothecenes, which cause various disorders, including cancer, in animals and humans

2001: Annual Disease Nursery Report

unpublishednot peer reviewe

Risk Evaluation of Household Hazardous Waste-A case study

ABSTRACTCertain chemicals in household products, when not used up to the completion at homes, may have the potential to spread hazards. These chemicals consist of heavy metals, pesticides and various types of solvent which may be persistent and can cause severe damage to public and environment. These types of waste shall be collected separately from other waste and are in general destroyed in some kind of specific destruction plant. Everyone who creates hazardous waste is responsible for a proper collection. When it comes to household hazardous waste (HHW) this could be a problem since it assumes that everyone in the society has enough knowledge of how to make a proper collection. Some types of hazardous waste are well-known and easy to recognize, e.g. solvents and batteries, but many people do not have any idea about some of the harmful products which they use and waste. Due to the fact that the hazardous waste is spread out in all households and that everyone is responsible for their own collection, leakages into the environment are possible in today\u27s system. Therefore, a fact finding study is needed to be conducted to see: what would be the main causes of the release of household hazardous wastes (HHW) into the environment during the collection and to evaluate the risks of such an event. This study is carried out based on two studies conducted at Chalmers University of Technology and focused on a case related to collection procedure of HHW in Gothenburg city, Sweden. The aim of the study is to develop a framework to find the most hazardous scenarios, the main causes of release of HHW into the environment. The goal is to propose a guide line to improve the collection procedure with lowest or acceptable risk.Initially, by using “what if” analysis the most important possible scenarios have been discovered. The results have been used in constructing a “fish bone” diagram to analyze the collection methods in Gothenburg city in order to discover the most important causes of the release of hazardous waste into the environment. Based on the fact that nearly 20% of the HHWs are not collected at all (reference), the most hazardous scenario is when “there is no attempt to collect the household hazardous waste”. Subsequently a few scenarios of release to nature have been chosen to be investigated by setting up a model for semi quantitative risk analysis. Risk ranking has been performed with the aim of determining areas associated with high and very high risks. Finally, potential improvements have been discussed

Abrasive Grit Application in Organic Red Pepper: An Opportunity for Integrating Nitrogen and Weed Management

Weeds are a top management concern among organic vegetable growers. Abrasive weeding is a nonchemical tactic using air-propelled abrasive grit to destroy weed seedlings within crop rows. Many grit types are effective, but if organic fertilizers are used, this could integrate weed and nutrient management in a single field pass. Our objective was to quantify the effects of abrasive grit and mulch type on weed suppression, disease severity, soil nitrogen availability, and yield of pepper (Capsicum annuum L. ‘Carmen’). A 2-year experiment was conducted in organic red sweet pepper at Urbana, IL, with four replicates of five abrasive grit treatments (walnut shell grits, soybean meal fertilizer, composted turkey litter fertilizer, a weedy control, and a weed-free control) and four mulch treatments (straw mulch, bioplastic film, polyethylene plastic film, and a bare soil control). Abrasive weeding, regardless of grit type, paired with bioplastic or polyethylene plastic mulch reduced in-row weed density (67 and 87%, respectively) and biomass (81 and 84%); however there was no significant benefit when paired with straw mulch or bare ground. Despite the addition of 6 to 34 kg N/ha/yr through the application of soybean meal and composted turkey litter grits, simulated plant N uptake was most influenced by mulch composition (e.g., plastic vs. straw) and weed abundance. Nitrogen immobilization in straw mulch plots reduced leaf greenness, plant height, and yield. Bacterial spot (Xanthomonas campestris pv. Vesicatoria) was confirmed on peppers in both years, but abrasive weeding did not increase severity of the disease. Pepper yield was always greatest in the weed-free control and lowest in straw mulch and bare soil, but the combination of abrasive weeding (regardless of grit type) and bioplastic or polyethylene plastic mulch increased marketable yield by 47% and 21%, respectively, compared with the weedy control. Overall, results demonstrate that when abrasive weeding is paired with bioplastic or polyethylene mulch, growers can concurrently suppress weeds and increase crop N uptake for greater yields