Aphids and therir parasitoids trends: Aphids and parasitoids population

Wheat (Triticum aestivum L.) and brassica (Brassica compestris L.) are the important crops in barani areas. The former is considered as important food source, while later is considered as important source of fodder and vegetable oil. In Pakistan, the wheat crop is cultivated over an area of 8.033 million hectares engaging 33 percent of the cultivated area of country each year and exhibits production around 23.5 million tons in 2007. At Pakistan level the production shows an increase of 9.5%. The GOP wheat production target is 5 million metric tons (GOP, 2007). Wheat being a major cereal occupies an eminent place in the economy of our country (Chowdhry et al., 1998).