Journal article

Publication year: 1988

Pages: 189-206

Journal: Journal of general and applied entomology

Volume number: 13

Issue number: 3-4

ISSN: 0171-8177

eISSN: 2363-7102

Publisher: Schweizerbart Science Publishers

Abstract: 
Pest populations are limited by a complex of factors, whereby natural antagonists may exert an important influence on the population dynamics of cereal aphids in different ways. During the investigation period 1984-1985, Sitobion avenae (Fabricius 1775) and Metapolophium dirhodium (Walker 1849) are common at all experimental sites in the area around Giessen. However, there are differences in their dominance depending on the site. The % of mummified and parasitized Aphidadae is higher in 1984 than in 1985, due to climatic conditions. Among the predators caught in the yellow pan trap, the most numerous are adults of Syrphidae, whereas in catches in window traps adults of Cantharidae were more abundant. The differences in trap catches regarding the kinds of traps and the abundance of predators in the field are discussed. The abundance and appearance of various genera of aphid preying Syrphidae, Coccinellidae and Chrysopidae is influenced mainly by microclimate, vegetation and density of cereal aphids. Propylea quatuordecimpunctata (Linnaeus 1758) and Episyrphus balteatus (De Geer 1776) are the most important species among Coccinellidae and Syrphidae resp''y, Chrysoperla carnea (Stephens 1835) is less abundant. Due to climate factors the efficiency of predators is higher in 1985 than in 1984, based on the same ratio between predators and prey. Larvae of Syrphidae are of special importance. During the investigation period, predators preying specifically on cereal aphids are first of all responsible for the final collapse of the aphid populations. The quantification of ''efficiency thresholds'' for predators and parasites based on the ratio between predators and pests or the rate of parasitation resp''y could be of great importance for integrated pest management systems.

Harvard Citation style: STORCKWEYHERMULLER, S. (1988) IMPACT OF NATURAL ENEMIES ON THE POPULATION-DYNAMICS OF CEREAL APHIDS ON WINTER-WHEAT IN UPPER HESSIA FRG (HOMOPTERA, APHIDIDAE), Journal of general and applied entomology, 13(3-4), pp. 189-206

APA Citation style: STORCKWEYHERMULLER, S. (1988). IMPACT OF NATURAL ENEMIES ON THE POPULATION-DYNAMICS OF CEREAL APHIDS ON WINTER-WHEAT IN UPPER HESSIA FRG (HOMOPTERA, APHIDIDAE). Journal of general and applied entomology. 13(3-4), 189-206.