Relative Resistance of Ulmaceae for Host Susceptibility, Feeding Preference, and Suitability for the Adult Japanese Beetle (Coleoptera: Scarabaeidae)

Abstract Laboratory feeding and fecundity bioassays, field defoliation surveys were conducted on 73 Ulmus eight Zelkova taxa to determine their relative susceptibility, preference, suitability for the adult Japanese beetle (Popillia japonica Newman). alata Michx., U. crassifolia Nutt., davidiana Planch., elliptica K. Koch, , glabra Hudson, laevis Pall., microcarpa, L.K. Fu, multinervis (syn. castaneifolia) Hemsl., parvifolia Jacq., propinqua Koidz., prunifolia Cheug Fu,, rubra Muhlenb., suberosa Henry, sukaczevii Andr., .szechuanica Fang., taihangshensis S.Y. Wang, thomasii Sarg, wilsoniana Schneid., ‘Frontier', ‘Homestead', ‘New Horizon', ‘Pioneer', ‘Patriot', ‘Morton' Accolade, Triumph, serrata (Thunb.) Mak. cultivars ‘Green Valley' ‘Village Green', Z. schneideriana Hand.-Mazz least susceptible and/or suitable reproduction. Percent leaf tissue removed was highly correlated with ratings, but not a good predictor of fecundity. Asian European elm leaves thicker compared North American elms, tougher leaves. Host susceptibility related thickness or toughness. Adult female beetles laid significantly more eggs when European, Eurasian, taxa. Hybridization appears affect host susceptibility. Results reported here provide new insight use Ulmaceae future reforestation tree breeding programs. Species used in this study: americana L., bergmaniana var. lasiophylla canascens Melville, carpinifolia Gled.., castaneifolia changii Hangchow, chenmoui Cheng, K.Koch., foliaceae Gilbert, gaussenii Cheng,, glaucescens Franch., Franch. lasiocarpa Rehd., Sarg., lanceaefolia Roxb., lamellosa C. Wang et S.L. Chang macrocarpa Hance, microcarpa (syn.U. procera Salisb, Henry Cheng Fu pseudopropinqua Li, pumila Muehl., serotina szechuanica Fang, taihangshanensis thomasii, wallichiana Mak., (Pall.) Koch., Hand.-Mazz,. sinica C.K. Schneid, Sassafras albidum (Nutt.) Nees.