Resistance characterization of different canola cultivars to mustard aphid, Lipaphis erysimi Kalt. (Hom.: Aphididae)

The mustard aphid, Lipaphis erysimi is one of the most sever pests of canola in Iran and other tropicalregions in the word. seven cultivars of canola including B. napus (cv. Licord, Elite, Okapi, Hyola 401,and RGS003), B. juncea (cv. Land race) and B. rapa (cv. Park land) were screened for antixenosis andantibiosis to L. erysimi under greenhouse condition at 25±2 , with 60±5% RH, and a photoperiod of16:8 (L: D) h). Results of antixenosis test demonstrate density of L. erysimi at different hours counting(48 and 72 h) was significantly different on canola cultivars (P < 0.05 and P < 0.01 after 48 and 72 h,respectively). Aphid density on Elite, Okapi, and RGS003 cultivars was significantly higher than othercultivars. In antibiosis test, results showed there was a significant difference of aphid life-table fertility‟parameters, in exception population doubling time (DT), on various canola cultivars (Intrinsic rate ofincrease (rm): P < 0.05; Net reproductive rate (Ro): P < 0.05; Mean generation time (T): P = 0.05 andFinite rate of increases (l): P < 0.05). The highest aphid rm was found on Land race cultivar (0.324female/female/generation), whereas the lowest one was recorded on Elite (0.278female/female/generation). Our results suggest that Elite, Okapi, and RGS003 cultivars were the mostresistance host for L. erysimi compare to the other tested cultivars. Resistant canola cultivars identified inthis study could be used for management control of mustard aphid.