Damage- and control threshold for the cereal aphid Macrosiphum (Sitobion) avenae (Fabr.) on wheat
1988
Wetzel, T. (Martin-Luther-Universitaet Halle-Wittenberg (German D.R.). Lehrstuhl fuer Phytopathologie und Pflanzenschutz) | Schuette, F.
For almost twenty years the cereal aphid Macrosiphum avenae is one of the key pests who damage wheat crops. About the 'Alarmzahl' (Buehl und Schuette 1971), the damage- and the control threshold, there are different opinions. Experiments on the development of cereal aphid populations, which have been going on for many years, clearly indicate that reliable results about the development of a gradation can only be made at the end of the wheat's blossom time. If there are three to five cereal aphids per ear then chemical control is necessary. This figure, which indicates when chemicals should be employed, renders routine employment of insecticides superfluous, and is a compromise between economical and ecological interests
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