The Chemical Mechanism of a Brown-Rot Decay Mimtic System and its Application in Paper Recycling Processes

This work is aimed at improving our current knowledge of the non-enzymatic inecl~anisins involved in brown-rot decay, as well as the exploration of potential applications of a brown-rot mimetic model system in paper recycling processes. The study was divided into two parts. The first part focussed on the chemical mechanisms involved in chelation and reduction of iron by a low molecular weight chelator (isolated from the brown-rot fungus Gloeophyllz~m tmbeum) and its model compound 2,3- dihydroxybenzoic acid (2,3-DHBA). Chelation as well as free radical generation mediated by this system were studied by ESR measurement. The results indicate that the effects of the chelator/iron ratio, the pH, and other reaction parameters on hydroxyl radical generation by a Fenton type system could be determined using ESR spin-trapping techniques. The results also support the hypothesis that superoxide radicals are involved in the chelator-mediated Fenton process. In the second part of the study, the effect of a chelator-mediated Fenton system for the improvement of deinking efficiency and the n~odification of fiber and paper properties was studied. For the deinking study, copy paper was laser printed with an identical standard pattern. Then repulping and flotation operations were performed to remove ink particles. Under properly controlled deinking conditions, the chelator mediated treatment (CMT) resulted in a reduction in dirt count over that of conventional deinking procedures with no significant loss of pulp strength. To study the effect of the chelator system treatment on the quality of pulp with different fines content, a fully bleached hardwood kraft pulp was beaten to different freeness levels and treated with the chelator-mediated free radical system. The result shows that virgin fiber and heavily beaten fiber respond differently to the free radical treatment. Unbeaten fibers become more flexible and easier to collapse after free radical treatment, while beaten fibers show a reduction in fines and small materials after mild free radical treatment.

Testing a Warning System for Anthracnose Fruit Rot on Day-neutral Strawberry

Anthracnose fruit rot (AFR) of strawberry is caused by three Colletotrichum spp. In the Midwest, however, only Colletotrichum acutatum is found. This fungus can attach itself to apparently healthy plants and spread throughout without causing symptoms on the foliage. When fruit begin to ripen and weather conditions are rainy and warm, AFR can suddenly cause great damage to the fruit. To protect against AFR where it has appeared in the past, growers need to spray every 7 to 10 days beginning at the start of bloom until harvest.

Las otras organizaciones político-militares : Reseña de: Esteban Campos y Gabriel Rot (2010), La Guerrilla del Ejército Libertador. Vicisitudes políticas de una guerrilla urbana. Colección Guerrillas olvidadas de la Argentina, Talleres Gráficos Su Impres S.A.

Fil: Stavale, Mariela. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Las otras organizaciones político-militares : Reseña de: Esteban Campos y Gabriel Rot (2010), La Guerrilla del Ejército Libertador. Vicisitudes políticas de una guerrilla urbana. Colección Guerrillas olvidadas de la Argentina, Talleres Gráficos Su Impres S.A.

Fil: Stavale, Mariela. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Las otras organizaciones político-militares : Reseña de: Esteban Campos y Gabriel Rot (2010), La Guerrilla del Ejército Libertador. Vicisitudes políticas de una guerrilla urbana. Colección Guerrillas olvidadas de la Argentina, Talleres Gráficos Su Impres S.A.

Fil: Stavale, Mariela. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

First report of Fusarium verticillioides causing stalk and root rot of sorghum in Spain

Podredumbre del tallo y la raíz del sorgo causada por Fusarium verticillioides en España

The role of secretion systems and small molecules in soft-rot enterobacteriaceae pathogenicity

Soft-rot Enterobacteriaceae (SRE), which belong to the genera Pectobacterium and Dickeya, consist mainly of broad host-range pathogens that cause wilt, rot, and blackleg diseases on a wide range of plants. They are found in plants, insects, soil, and water in agricultural regions worldwide. SRE encode all six known protein secretion systems present in gram-negative bacteria, and these systems are involved in attacking host plants and competing bacteria. They also produce and detect multiple types of small molecules to coordinate pathogenesis, modify the plant environment, attack competing microbes, and perhaps to attract insect vectors. This review integrates new information about the role protein secretion and detection and production of ions and small molecules play in soft-rot pathogenicity.

The effects of storage duration, temperature and cultivar on the severity of garlic clove rot caused by Fusarium proliferatum.

Diseases that affect garlic during storage can lead to severe economic losses for farmers worldwide. One causal agent of clove rot is Fusarium proliferatum. Here, the progress of clove rot caused by F. proliferatum and its dependence on different storage conditions and cultivar type were studied. The effect of temperature on mycelial growth, conidial viability, and fungal survival during garlic commercial storage was documented. Samples of 50 bulbs from a randomized field trial with three different clonal generations for purple garlic (F3, F4 and F5) and the F4 clonal generation for white garlic were labeled and stored for two months (short-term storage). In addition, another sample of the F5 clonal generation of purple garlic was stored for 6 months after harvest (long-term storage). The presence of the pathogen and the percentage of symptomatic cloves were evaluated. A notable difference in the rot severity index (RSI) of different garlic varieties was observed. In all studied cases, clove rot increased with storage time at 20 ◦ C, and the white garlic variety had a higher index of rot severity after two months of storage. Additionally, there were clear differences between the growth rates of F. proliferatum isolates. Studies conducted on the temperature responses of the pathogen propagules showed that expo- sure for at least 20 min at 50 ◦ C was highly effective in significantly reducing the viability of fungal conidia. Pathogenicity studies showed that the fungus is pathogenic in all commercial varieties. However, there were significant differences in varietal susceptibility between Chinese and white garlic type cultivars (81.84 ± 16.44% and 87.5 ± 23.19% symptomatic cloves, respectively) and purple cultivars (49.06 ± 13.42% symptomatic cloves)

Des. Erasmi Rot. Ecclesiastae sive de ratione concionandi libri quatuor opus recens nec antehac [sic] à quo quam excusum

Nombres de imp. constan en colofón