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A sex pheromone has been isolated and identified from virgin females of the southern corn rootworm (SCR),Diabrotica undecimpunctata howardi Barber. The synthesized compound, 10-methyl-2-tridecanone was shown to be attractive to males of the SCR, and also to males ofD. u. undecimpunctata Mannerheim, the western spotted cucumber beetle (WSCB), and ofD. u. duodecimnotata in Mexico. Males of both the SCR and the WSCB strongly preferred theR over theS enantiomer. The resolved enantiomers were not tested againstD. u. duodecimnotata.

A sex pheromone has been isolated and identified from virgin females of the western corn rootworm (WCR),Diabrotica virgifera virgifera LeConte. The synthesized compound, racemic 8-methyl-2-decanol propanoate, was equal in attraction to the natural pheromone when tested in the field as a trap bait against three taxa ofDiabrotica known to respond to pheromone extracts from female WCR. Five taxa (D. virgifera virgifera; D. virgifera zeae Krysan and Smith, Mexican corn rootworm;D. longicornis barberi Smith and Lawrence, northern corn rootworm;D. longicornis longicornis (Say); andD. porracea Harold) were attracted to traps baited with 8-methyl-2-decanol propanoate. The response of male northern corn rootworms (NCR) in the field peaked at a relatively low concentration of 8-methyl-2-decanol propanoate and then was severely reduced at the higher concentrations tested. Conversely, the response of male WCR in the field continued to increase up to the highest dose tested.

Quantitative determinations of lipoxidase in wheat were made on five milling fractions from four wheat varieties, including two hard red winter and two hard red spring wheats. Lipoxidase content decreased with increasing refinement and was lowest in the flour fraction. In general, the mill fractions from spring wheats exhibited slightly higher lipoxidase content than the corresponding mill fractions from winter wheats.Aqueous extracts from soybeans (variety Hawkeye) and wheat (variety Selkirk, break shorts fraction) were adjusted in concentration so that the lipoxidase activity with respect to linoleic acid was approximately the same. The diluted extracts were then tested for their ability to oxidize other lipid substrates with the necessary 1,4 pentadiene system. Soybean lipoxidase was far more reactive toward methyl linoleate and trilinolein than wheat lipoxidase. Mono‐ and dilinolein were relatively unreactive in both systems although dilinolein was a better substrate in the soybean system than in the wheat. Neither system oxidized highly unsaturated digalactosyl diglycerides alone. However the soybean extract oxidized this substrate to a small extent in the presence of catalytic amounts of linoleic acid while, under identical conditions, the wheat extract remained inactive.Polyacrylamide gel electrophoresis of the aqueous extracts of soybeans and wheat‐milling fractions coupled with a staining procedure specifically for lipoxidase indicated three to four isoenzyme bands in the soybeans and two to four isoenzyme bands in the wheat‐milling fractions. Isoenzymes may be responsible for differences in enzymatic activity on various substrates.