Responses by five species of cucujid grain beetles (mixed-sex adults) to various volatiles were assessed by means of a two-choice, pitfall olfactometer. The test volatiles were short-chain alcohols and ketones known to be produced by fungi. Both racemic and chiral 1-octen-3-ols were strong attractants forCryptolestes ferrugineus (Stephens), as had been found previously forOryzaephilus surinamensis (L.),O. mercator (Fauvel), andAhasverus advena (Waltl). 3-Methylbutanol was another good attractant for these four cucujids, and it was the only test compound to whichCathartus quadricollis (Guér.) responded positively. 1-Octen-3-one, racemic 3-octanol, and 3-octanone showed various degrees of attractiveness for the former four species of cucujids.O. surinamensis was the only species of test beetle to show much positive response to 2-phenylethanol and ethanol. ForO. mercator andO. surinamensis, 3-methylbutanol enhanced positive response to their respective cucujolide aggregation pheromones.

Two biologically active macrolides were isolated from Porapak Q-captured beetle and frass volatiles ofCryptolestes turcicus (Grouvelle) and identified spectroscopically as (Z,Z)-5,8-tetradecadien-13-olide (I) and (Z)-5-tetradecen-13-olide (II). Natural I was active alone and was synergized by inactive II. The pheromones were male-produced but attractive to both sexes. Pheromone production increased dramatically when insects were aerated on a food source. Pure (R)- and (S)-I were inactive, but mixtures of (R)- and (S)-I were active, the first reported instance of enantiomeric synergism in the Cucujidae.

The most prominent beetle-produced volatiles identified in the abdominal extracts of maleDryocoetes confusus Swaine after they had bored for 24 hr in logs of subalpine fir,Abies lasiocarpa (Hook.) Nutt. were:exo andendo-brevicomin,trans-verbenol, verbenone, myrtenol,trans-pinocarveol,cis- andtrans-p-menthen-7-ol, 3-caren-10-ol, and several monoterpenes and sesquiterpenes. Myrtenol was the only conspicuous compound in extracts from males that had been exposed toA.lasiocarpa resin volatiles for 24 hr. Laboratory bioassays indicated that both (-)- and (+)-exo-brevicomin were attractive to femaleD. confusus, and that the (-) enantiomer did not inhibit response to its antipode. Results from field trapping experiments indicated that bothero-brevicomin and myrtenol are aggregation pheromones forD. confusus.exo-Brevicomin baits were effective in causing attack byD. confusus on baited and surrounding trees, suggesting that this pheromone may have utility in manipulating populations of the beetle.

When feeding on rolled oats, male square-necked grain beetles,Cathartus quadricollis (Guér.), produced the aggregation pheromone (3R,6E)-7-methyl-6-nonen-3-yl acetate, for which the trival name "quadrilure" is proposed. The pheromone was highly attractive to both sexes in a two-choice, pitfall olfactometer modified to retain responding beetles by placing a food stimulus (an oat flake) in the glass vials containing the experimental and control stimuli. TheS enantiomer of the pheromone was inactive. Males also produced small amounts of (E)-7-methyl-6-nonen-3-one, (E)-7-methyl-6-nonen-3-ol, and (6E)-7-methyl-3-propyl-2,6-nonadienyl acetate, but these compounds were inactive in the laboratory bioassay. Segregated males and females both produced (R)-(-)-1-octen-3-ol, which by itself was repellent to both sexes but did not diminish beetle response to the aggregation pheromone.