the seasonal population fluctuation of the green peach aphid, myzus persicae sulzer (hom., aphididae) on some potato cultivars in ardabil

abstract myzus persicae sulzer is one of the serious pests in potato fields which has the ability of transmitting several viruses to the potato crop. throughout summer of 2008, field studies were carried out in ardabil to evaluate the seasonal population fluctuation of this aphid on 10 potato cultivars: granola, satina, moren, aozonia, cosima, agria, cosmos, kondor, diamant and savalan. density of aphids on both first and fifth compound leaves of these cultivars was counted every three days. analysis of variance showed significant differences among the cultivars. the highest density of aphid was on aozonia cultivar. even though there were no significant differences between the other cultivars but the lowest numbers of aphids were on cosima and cosmos cultivars, respectively. two peaks of aphid's population were observed in ardabil. consequently, in ardabil's climate condition and among the tested cultivars, m. persicae showed less preference toward cosima and cosmos.