Effect of eutrophication on the infestation of phragmites communis by the mealy plum aphid hyalopterus pruni in berlin west germany
Raghi-Atri, F.
Zeitschrift für Angewandte Zoologie 63(3): 365-374
1976
ISSN/ISBN: 0044-2291
Accession: 005237495
Of the complex of factors which may be important for the influence of eutrophication on the decrease of reeds, the infection of P. communis Trin. by H. pruni Geoffr. was investigated in 2 reed-beds in Berlin [West Germany] which differ in their intensity of eutrophication. The following parameters were investigated: N content of surface water, percentage N content of the soil at dry weight (105.degree. C), ash content of the whole plant, average number of shoots/m2, average leaf area, aphid infection for a given leaf area (bottom side of the leaf), leaf color and potential length of exposure to the sun. H. pruni attacked the stations with different intensity, intense attack leading to a damage of the assimilating leaf area and thus to an early change of the conditions of production of the plant. Relationships were found between the quantity of available N, ash content of the plant, leaf area, leaf color and intensity of infection. Further environmental factors, such as the microclimate of the reed-belt, have to be considered as well. The more highly eutrophicated station showed a high ash content, a large leaf area and the formation of a greyish green leaf color, as well as a heavier attack of P. communis by H. pruni.