DIURAPHIS NOXIA)MORDVILKO ارزيابي مقاومت لاين هاي پيشرفته گندم به شته روسي

Evaluation of Resistance to the Russian Wheat Aphid, Diuraphis noxia (Mordvilko), in some Advanced Wheat Lines

Eleven advanced wheat lines (Triticum aestivum), produced by Seed and Plant Improvement Institute were evaluated for resistance to Russian wheat aphid (Diuraphis noxia). Quantitative damage ratings, based on the amount of leaf curl and chlorosis showed that five of the lines had higher levels of resistance to the aphid. These lines showed significantly lower leaf curl in comparison with c.v. Sholeh as a susceptible control. Additional tests to determine the mechanisms of resistance were performed with these five lines. Various levels of antixenosis, antibiosis and tolerance were exhibited in the lines. In antixenosis test, number of aphids on all lines was significantly lower than c.v. Sholeh, 24, 48 and 72h after release. In antibiosis test, fecundity and daily nymphal production were significantly lower in these lines than susceptible control. In tolerance test, percentage of damage (plant height reduction) was significantly lower in C-A123 and C-All 1 lines than in Sholeh. Plant resistance index (PRI) was 5.27 and 4.78 in C-A/23 and C-A/15, respectively, compared to 1.00 in c.v. Sholeh. These results indicated that lines C-A/23 and C-A/l 5 are more resistant than the other nine lines.