author(s)
Imtiaz Ali Khan, Mansoor Ahmad, Sajjad Hussain, Rasheed Akbar, Muhammad Saeed, Abid Farid, Ruidar Ali Shah, Walija Fayaz, Mir Manzar Ud Din, Muhammad Naeem

abstract
The present study on aphid’s density, yield and yield components of 12 Brassica genotypes under screen house conditions was conducted at the Institute of Biotechnology and Genetic Engineering (IBGE), The University of Agriculture, Peshawar (UAP) during 2006-08. The 12 genotypes belonged to four Brassica genera viz. Brassica napus, B. juncea, B. campestris and B. carinata. The results revealed that overall mean aphid density was highest (138.9 aphids plant-1) on Rainbow and lowest (59.00 aphids plant-1) on T-16-401. Overall mean seed yield was significantly higher (4.33 g plant-1) of Ganyou-5 and lowest (1.79 g plant-1) of Oscar. Overall mean straw yield was significantly higher (18.63 g plant-1) for Westar and lower (12.56 g plant-1) for Peela Raya. Overall mean plant height was significantly higher (153. 4 cm plant-1) for Peela Raya and lower (82.10 cm plant-1) for Westar. Overall mean number of branches were significantly higher (12.05 plant-1) in Peela Raya and lower (5.39 plant-1) each in Rainbow and Torch. Overall mean siliquae mr was significantly higher (32.67 plant-1) in Westar and lower (8.61 plant-1) in Peela Raya. Overall mean number of leaves were significantly higher (38.28 leaves plant-1) in Altex and lower (21.83 leaves plant-1) in Legend. The present results might be helpful in using host plant resistance in an integrated pest management program against B. brassicae in Brassica genotypes.