Effects of abiotic factors on population of Brevicoryne brassicae L. on canola crop in Varamin

Subject Areas : entomology and othea arthropods

A. A.  Keyhanian ¹ (Iranian Research Institute of Plant Protection, Tehran, Iran)
M. V.  Taghaddosi ² (Agricultural and Natural Resources Research Center of Zanjan, Zanjan, Iran)

Received: 2010-02-23 Accepted : 2010-05-23 Published : 2010-05-22

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Abstract :

Cabbage aphid, Brevicoryne brassicae L. is one of the most important insect pests of canola crop causing qualitative and quantitive damage by sucking plant sap. Field studies during 2001-2003 revealed that pest starts attacking the canola fields in different times of the season over the cultivation areas of the country. Under Tehran province (Varamin region) conditions initial infestation and the establishment of colonies of aphid were observed on young seedling of canola (winter crops) during November and subsequent spread of infestation occurred after cold period of winter in February and March. Maximum population of B. brassicae L. was recorded during April-May. The multiplication of the aphid is governed by day time abiotic factors like temperature, humidity, and sunshine. Path coefficient analysis of the impact of the abiotic factors showed that minimum temperature, minimum relative humidity and sunshine imposed direct positive effect on the pest.