| Popis: |
Possibilities of genetical control in aphids (Homoptera: Aphidina). In principle, genetical control methods (sterile male technique, incompatibility technique) can be used in all holocyclic-heterogenetic aphid species, provided that the following basic requirements are met: 1. Hibernation has solely to be performed on the primary host, by the diapause egg produced by the bisexual generation, or by the first larval stage of the fundatrix developing from the gamogenetic egg. 2. The to be sterilized male of the bisexual generation must be winged, and thus have a wider range of action than the possibly unwinged female to be mated by it. On the contrary, all heterogenetic-holocyclic species in which, a parthenogenetic generation hibernates at the secondary or also at the primary host, have to be omitted from genetical control. Equal obstructions are effective for anholocyclic-parthenogenetic species which solely hibernate by non-gamogenetic generations. On the strength of these biological facts the following conclusions have to be noted: As far as aphids are concerned, a general refusal of chemical insecticides and their substitution by biological or genetical control methods, is not possible. On the other side, there are many aphid species which meet all preconditions for the application of genetical and thereby environment preserving control methods. To use these possibilities should be the task of further research. Zusammenfassung Eine Prufung der eidonomischen und okologischen Eigenheiten der Blattlause ergibt, das viele Biospecies dieser Schadlingsgruppe alle Voraussetzungen zur Anwendung neuzuerarbeitender genetischer Bekampfungsverfahren (Sterilmannchen-Methode, Inkompatibilitatsmethode) bieten: Ausschlieslicher Vollzug der Uberwinterung durch eine gamogenetische Generation und Vorhandensein geflugelter Sexualis-♂♂. Alle anderen Aphidina-Biospecies und samtliche Agamospecies dagegen sind diesen umweltschonenden Methoden nicht zuganglich. |
