Effects of Nutrient Impregnation of Pine Sapwood on the Growth of Larvae of the Old-House Borer (Hylotrupes bajulus (L.))1

Abstract

Comparisons were made of the growth of the larvae of Hylotrupes bajulus (1.) in untreated Pinus sylvestris logs with growth in logs impregnated under pressure with aqueous solutions of (a) 0.01% aureomycin (chlortetracycline hydrochloride-Lederle), (b) 0.50% bactopeptone (British Drug Houses), (c) 0.01% aureomycin plus 0.50% peptone, (d) 1.00% ammonium nitrate, and with water. Following 12 months storage in an incubator the effects of the above treatments, compared with untreated controls, were as follows: (a) no significant effect on larval growth; (b) larval growth significantly increased; (c) the same as (b) (the presence of aureomycin did not, therefore, alter the effect of the peptone); (d) all larvae died at an early stage. In the logs impregnated with water, larval growth was slightly but not significantly retarded. None of the substances produced greater uniformity of larval growth.