POPULATION OF APHIDS ON DIFFERENT VARIETIES/LINES OFWHEAT AND THEIR EFFECT ON YIELD AND THOUSANDS GRAINWEIGHT

An experiment was conducted at Agricultural Research Institute, Tarnab, Peshawar, Pakistan during 2009- 2010 to study the population trend of wheat aphids on different varieties/ lines of wheat and their effect on the yield and thousands grain weight. Aphids attack started in first week of January, increased during February and March, peaked on 13th March, and then declined afterwards till complete disappearance till 6th April. The overall mean number of aphids per plant was higher on wheat line PR-1 (42.20 aphids per plant), which was followed by Khber-87 (32.57 aphids per plant) , Pirsabak -2005 (29.36 aphids per plant) , KT-2004 (KT-09) (21.22 aphids per plant), NRL 0302 (Barsat-09) (20.29 aphids per plant), Saleem-2000 (19.92 aphids per plant) , Pirsabak-2008 (15.71 aphids per plant), PR-2 (13.34 aphids per plant) and Pirsabak- 2004 (12.89 aphids per plant) . Wheat yield was highest for Pirsabak 2004 (3048 kg ha^-1) lowest for PR-1(2243 kg ha^-1). Pirsabak 2004 yield higher grain weight then all the other wheat lines.