USE OF TRIADIMEFON TO CONTROL WHITE-PINE BLISTER RUST

White pine seedlings were treated with triadimefon two weeks prior to natural inoculation with Cronartium ribicola and were observed for two growth seasons. During the second growth season in the greenhouse the incidence of blister rust symptoms was 70.8% for the untreated contro ls, whereas only 3.8% of the treated seedlings showed symptoms of blis ter rust. Triadimefon offers effective protection against white pine b lister rust infection and would enable the production of bare root see dlings in areas prone to blister rust infection.