Resistance of Different Wheat Lines to Rhopalosiphum padi (L.) (Aphididae: Homoptera) in Pakistan

The nature of resistance in eleven NUWYT Rain Fed (RF) wheat advanced lines and in one variety of year 2004-05 were determined against Rhopalosiphum padi L. (Bird Cherry Oat Aphid). Results of Seedling Bulk Tests of wheat lines showed that three lines namely PR-87, NR-234 and NR-241 were resistant, while the one variety namely Chakwal-97 and one line V-002467 were susceptible to aphid attack whereas seven lines were moderately resistant. Most suitable wheat lines were resistant and moderately resistant lines with damage rating of 4. Another set of experiments was conducted for Antixenosis (Non-preference) Tests to find out the least preferred line in same rain fed wheat lines. In the Antixenosis test, two lines DN-44 after 24 hrs. and NRL-2017 after 48 hrs. were highly preferred in Seedling Bulk Test three lines namely PR-87, NR-234 and NR-241 were resistant, while V-00BT004 line was least preferred, after 24 hrs and 48 hrs of release of aphids in antixenosis Tests, so it was the most suitable line regarding Free Choice test against this insect pest.