Biological control of water hyacinth by a mycoherbicide in Egypt.

摘要: An Alternaria eichhorniae islolate (#5) pathogenic to water hyacinth was discovered in Egypt 1984. This fungus appeared be host specific and capable of severely damaging thus suppressing the weed. The major constraint its use as a biocontrol agent—the need for long period dew—has been overcome through formulations using oil emulsions. article summarises results 16 years research culminating confirmation feasibility #5 biological control agent against Egypt. WATER creates serious problems Egypt: weed not only affects irrigation, flow, use, navigation, it also poses health risks by enabling breeding mosquitoes schistosomes (bilharzia) other human parasites. Water quality is affected well, because increasing accumulation detritus. Fishing may competitive advantage ‘trash”’ fish species weed-infested water. In many instances, are killed when oxygen levels depleted plant respiration decomposition senescent vegetation. problem particularly severe Nile Delta irrigation systems. view encountered management, attention has recently centred on control. Biological could provide lasting, cost-effective, environmentally safe solution, theoretically best method solving problem. Recent conferences panels have stressed greater renewed emphasis biologically based alternatives (Delfosse Spencer 1997; Charudattan et al. 1996). Isolation, Identification, Pathogenicity Testing Host Range Determination Between 1984 1986, surveys were made (Dakahlia Damietta governorates) where accumulations floating mats located (Shabana 1987). Two hundred fungal isolates belonging several genera isolated from diseased plants. These included three spp. (numbered 3, 5, 6) Dakahlia Governorate. associated with leaf blight that spread rapidly disease foci Initially, identified alternata (Fr.) Keissler reported potential agents (Elwakil 1989). However, variability colour colonies conidial dimensions among suggested more than one involved. Taxonomic identification level * Plant Pathology Department, Faculty Agriculture, Mansoura University, El-Mansoura, Email: ymsh@mum.mans.eun.eg † University Florida, Gainesville, FL 32611-0680, USA.