ISSN:
1573-8248
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary Investigations on appearance and periodicity of diseases and parasites of white grubs of the European cockchaferMelolontha spec. (M. melolontha L. andM. hippocastani F. in mixed populations) were carried out in Lorsch (Germany: pine-beech-forest, Rhine-valley, southwest of Frankfurt am Main). A rickettsial disease was dealt with in previous papers (Rickettsia melolonthae Krieg), the present one describes the other observed mortality factors. They were: Bacteria: only unspecific species occured, spore-forming and specific ones never (A «black-spot disease» of white grubs might probably also be caused by bacteria). Fungous infections were caused byBeauveria tenella (delacr.)Siem. (=B. bassiana (Bals.)vuill.) andFusarium spec., Protozoan infections by the FlagellataPolymastix melolonthae (grassi 1881) and the MicrosporidianPlistophora melolonthae Krieg. Parasites were the NematodesDiplogasteroides berwigi n.spec. andRhabditis (Caenorhabditis) dolichura Schneider 1866 and from insectsMegaselia rufipes Meig. (Dipt.-Phoridae) andDexia rustica F. (Dipt.-Larvaevorid.). Well characterized by external symptoms but not so regarding the causal agent was the “Wassersucht” (dropsy). Numerous grubs died “without disease recognition” (“Ohne Krankheits-Befund”, abbrev. o.K.B.). Here physiological besides pathological causes are suggested. All these factors showed a distinct periodicity of infection and mortality in the laboratory and in the field. Their general outlines, the periods of infection in the field and those of mortality in the field and the laboratory are demonstrated and discussed, as well as the retardation of development of the infested hosts.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02372202
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