Invasive Species Compendium

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Abstract

The field population dynamics and optimum control period of wheat aphids in Chaoyang Region, Liaoning.

Abstract

The statistical analysis of population data obtained from 1991 to 2001 in Chaoyang Region, Liaoning, China, revealed that in the absence of pesticide application, wheat aphids (Rhopalosiphum padi, Schizaphis graminum and Macrosiphum avenae [Sitobion avenae]) showed 5 stages of fluctuations in field population. Generally, the population of wheat aphids varied from 3000 to 6000 per 100 wheat stems, but reached 10 000 to 20 000 per 100 stems during severe infestation. The optimum control period was from 10 to 20 May, which can be adjusted to a difference of 1 or 2 days.