Population Studies of Pratylenchus penetrans and its Effects on Peach Seedling Rootstocks1

Abstract Field samplings in 3 peach orchards with 4 seedling rootstocks showed that Siberian C seedlings had significantly higher levels of Pratylenchus penetrans [(Cobb) Filip, and Stek.] populations in both root tissues and surrounding soil than 3 other seedling rootstocks tested. Little difference in nematode populations could be shown between seedlings of Veteran, Harrow Blood and Rutgers Red Leaf. Greenhouse studies of infected and nematode-free seedlings of these rootstocks confirmed field results. Significant reduction in growth occurred in all the rootstocks tested, with Siberian C seedlings being the most severely affected. Nematode control and plant breeding implications are discussed.