Weevil resistance of progeny derived from putatively resistant and susceptible interior spruce parents

摘要: Abstract Controlled-cross progeny of interior spruce ( Picea glauca (Moench) Voss × engelmanni Parry ex Engelm.) parents ranked as resistant or susceptible to the white pine weevil, Pissodes strobi (Peck) were screened for resistance same insect by augmentation trial site with weevils. Progeny from two (R R progeny) sustained significantly fewer weevil attacks (13% trees attacked) in year following augmentation, than (S S (68% attacked). obtained crossing one and parent intermediate attack levels (47% Characteristics bark resin canals crosses explored using microscopy techniques. Bark canal density was highest progeny, lowest progeny. There a negative correlation between percentage attacked each cross average outer cross. A discriminant function developed that distinguished characteristics. The characterized positive coefficients inner size, coefficient thickness. Thus, thin bark, large dense are more likely be P. .