Evaluation of resistance in wheat against Rhopalosiphumpadi (L.) (Homoptera:Aphididae) Under laboratory Conditions

For the evaluation of resistance, twelve rainfed wheat varieties/ lines of National Uniform Wheat Yield Trials (NUWYT) 2004-05 were used. Among the tested germplasm (one variety and 11 lines of wheat), V-5 line was found resis- tant and NRL-2017 line was found susceptible to Rhopalosiphum padi. The results of Antixenosis Test indicated that two wheat lines, V-5 and PR-83 were least pre- ferred and three lines viz., NRL-2017, V-00055 and V-00BT004 were highly pre- ferred by the test insect. The results of Antibiosis Test showed that PR-83 line was least fecund whereas NR-241 and V-00055 lines were highly fecund. The results of Tolerance Test indicated that four varieties, PR-83, V-5, SN-128 and NR-241 were highly tolerant, while only one line, V-00BT004 was least tolerant. To avoid harm- ful effects of this insect pest, only resistant, least preferred, least fecund and highly tolerant lines must be used in wheat breeding programmes.