Abstract: In order to provide scientific suggestions for selecting new poplar strains resistant to insects, the resistance of 18 clones of Populus deltoids to 3rd instar larva of Clostera anastomosis was evaluated and analyzed in laboratory conditions （28±1℃, RH 70%, 16L∶8D）. The choice and no-choice experiments indicated that eleven of 18 clones had higher resistance to C. anastomosis larvae than I-72 (control). Main nutrients and secondary metabolites were measured, and activities of digestive and protective enzymes and their effects on food utilization and insect development were also studied. The results showed resistance of the clones tested in P. deltoides to C. anastomosis larvae was statistically and positively related with the content of phenolic compounds of their leaves. Differential effects of clones of P. deltoides on the growth and food utilization existed in larvae of C. anastomosis, as showed in the changes of the main indicators of growth and food utilization, such as larval weight, daily body weight gain, relative growth rate, approximate digestibility, efficiency of conversion of ingested food, and efficiency of conversion of digested food. Differential effects of clones of P. deltoides on food intake and feces excretion in larvae of C. anastomosis also existed. The results suggest that C. anastomosis are more sensitive to secondary metabolites and the clones of P.deltoides have apparently active effects on activities of SOD and CAT in C. anastomosis larvae.

Key words: Populus deltoides, Clostera anastomosis, choice test, resistance, clone, food utilization