Abstract: A field investigation was conducted on the spatial distributions of Sitobion avenae and its main natural enemies under wheatoilseed rape intercropping and methyl salicylate application. With the development of wheat plant, an alternation from aggregation to uniform was observed in the spatial distribution of S. avenae under the intercropping and methyl salicylate application, being more obvious under the interaction of the two practices. The spatial distribution of S. avenae natural enemies was in accordance with that of the aphid. These results could be used for the reference of sampling investigation and forecast of wheat aphid and its natural enemies in field.  

Key words: wheat-oilseed rape intercropping, methyl salicylate, Sitobion avenae, natural enemy, distribution pattern.