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In 2000, cucumber ( Cucumis sativus cv. Albatros) in several commercial glasshouses in south-eastern Spain (Almería) exhibited symptoms of wilt, yellowing and necrotic streaks on the stems. Internal, vascular discoloration in affected plants extended from the base of the stem upward.Initial observations were reminiscent of fusarium wilt disease of cucumber, caused by Fusarium oxysporum f. sp. cucumerinum , as described by Owen (1955). Pure colonies of fungi were isolated from surface-disinfested (with flame) stem segments, cut at 0·5 m above the hypocotyl, on potato dextrose agar (PDA) medium. Isolates were identified as Fusarium oxysporum due to occurrence of typical macroconidia with foot-shaped basal cells, microconidia borne in false heads only on monophialides and chlamydospores. To confirm pathogenicity, eight isolates (1-week-old cultures grown on PDA) were used to root-dip inoculate (1 × 10 6 conidia mL − 1 ) 1-week-old seedlings of cucumber cvs Nevada and Albatros. Seedlings were then transplanted into pots containing vermiculite growth medium and placed in a glasshouse. Of the tested isolates, all but one were pathogenic, causing wilt symptoms or death in 60 -100% of dip-inoculated plants, from which F. oxysporum was consistently reisolated. Symptoms observed in inoculated plants were similar to those observed in cucumber plants in commercial glasshouses. This is the first report of F. oxysporum causing wilt of cucumber in Spain. ReferenceOwen JH, 1955. Fusarium wilt of cucumber. Phytopathology

Most developing countries lack sufficient legal and management infrastructure to dispose of urban solid waste (USW). The continuous increase of USW generation requires evaluating different treatments for developing countries based on the life cycle assessment methodology to compare the environmental impact by reducing greenhouse gases and leachate. Hydrothermal carbonization (HTC) and gasification processes are presented as potential solutions for USW treatment due to their efficiency in producing energy for local requirements. This study aimed to compare both technologies for Temuco and Padre Las Casas cities in Southern Chile that show severe air pollution and USW management problems. The results indicated that gasification had a better environmental performance than HTC when the conversion of 1 ton of organic fraction USW was analyzed. However, since HTC achieved higher energy efficiency, it had a lower environmental impact than gasification, considering the production of 1 MWh. For a definitive choice of the technology to be used, it is necessary to compare other variables, including economic and social aspects, to provide a holistic perspective.

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