R. C. Gueldner

Constituents of the cotton bud

Abstract The investigation of the alcohol fraction of the essential oil of cotton ( Gossypium hirsutum L. var. Deltapine Smoothleaf) with an integrated gas-liquid chromatography-mass spectrometry system resulted in the identification of 17 additional alcohols and β-ionone. Tentative assignments were made for 4 other alcohols. None of these has previously been reported in cotton.

Volatile constituents of the boll weevil

Abstract When the distillable oil from adult boll weevils, Anthonomus grandis , of both sexes was investigated with an integrated gas chromatographymass spectrometry system, evidence was obtained for a number of mono- and sesquiterpene hydrocarbons and some substituted anilines including o -toluidine; for some C 5 and C 6 alcohols and monoterpene alcohols; and for at least one sesquiterpene alcohol. The major components were a series of alkanes, alkenes, and alkyl alcohols of high molecular weight. This investigation was part of a study made to identify possible additional components of the pheromone produced by the boll weevil.

The boll weevil‐cotton plant complex

Abstract The boll weevil, Anthonomus grandis Boheman was introduced from Mexico into the United States about 1892. More than three‐fourths of all insect losses to cotton in this country have been attributed to this insect, and it is generally agreed that cotton cannot be profitably grown in areas where it occurs without adequate control measures. This review summarizes the chemically oriented research conducted on this plant‐insect complex during the past seventy years with emphasis on the program conducted since 1962 at the Boll Weevil Research Laboratory. Of plant‐insect relationships, host plant resistance, feeding stimulants, plant attractants, and plant constituents are discussed. Insect‐insect relationships treated include insecticides, chemosterilants and hormones, sex attractants, and insect constituents. The development of an integrated program for the attempted eradication of this insect is also discussed.

A gas chromatographic survey of the volatile fractions of twenty species of insects from eight orders

Abstract The profiles of the essential oil of twenty species of insects from eight orders were obtained by steam distillation and analysis by gas chromatography. For six of the seven species analysed separately by sex, the profiles showed prominent differences. In Coleoptera, phylogenetic similarities were apparent. Sex attractant activity has been reported in only seven of the twenty species investigated.

Sterol galactosides and sterol esters of the cotton bud

About 60% of the total sterols in the cotton bud appeared in the free state; the esterified sterol glycosides contained about 50% saturated fatty acids, largely palmitic acid; the principal unsaturated fatty acid was linolenic acid. β-Sitosterol was the major sterol in all classes of sterol derivatives. The sugar moiety of the esterified sterol glycosides and the sterol glycoside was galactose. Efforts are continuing to evaluate the minor sterols of cotton buds, some of which appear to be hydroxylated ecdysones, and to study their relationship to the development of the Boll weevil,Anthonomus grandis Boheman.

Cotton Plant and Insect Constituents That Control Boll Weevil Behavior and Development

The boll weevil, Anthonomus grandis Boheman, was introduced from Mexico into the United States (near Brownsville, Texas) about 189271. By 1922 the pest has spread into cottongrowing areas of the United States from the eastern two-thirds of Texas and Oklahoma to the Atlantic Ocean. Its recent extension into west Texas now threatens cotton in New Mexico, Mexico, Arizona and California. As early as 1895, recognition of the tremendous damage caused by this insect was noted, and Townsend (1895) suggested that cotton growing be terminated in the region then infested, and that the cotton free zone be maintained along the Rio Grande River bordering Mexico. Several other entomologists studied and suggested ways to control the boll weevil. Howard (1896) reported on the use of, and lack of response to, light traps. Malley (1901) studied the use of poisons for weevil control as well as the use of cotton as trap plants. An act was passed in 1903 offering

Lipids and fatty acids of the southwestern corn borer, Diatraea grandiosella☆

50,000 as a cash reward for a practical remedy for controlling the boll weevil. Sanderson (1904) reported that hand picking of infested squares had been tried and was meeting with little success.

Variations in lipid content of the boll weevil during metamorphosis

Abstract The lipids of the adults and of several immature stages of the southwestern corn borer, Diatraea grandiosella , were studied after they were fed natural corn stalks or artificial diets. Linoleic acid (18:2) was the major fatty acid of the neutral lipids in both the natural and the artificial diets, but aleic acid (18:1) was the principal neutral lipid in all insect stages. Also, linoleic acid and oleic acid were the principal acids in the insect phospholipids of all stages. The content of linoleic acid in the natural diet was also high, but that in the artificial diet appeared to be much too low for insect requirements. Phosphatidyl choline (PC) and phosphatidyl ethanolamine (PE) were the major phospholipids in all growth stages. Thus, in larvae diapausing in the field, the unsaturated fatty acid content of PC was 59·3 per cent, primarily 16:1 and 18:1, and PE was 87·4 per cent, primarily 18:1, 18:2, and 18:3, and the fatty acids in the number 1- and 2-positions of PC were 53·6 and 97·2 per cent unsaturated, respectively. The haemolymph of diapausing southwestern corn borer larvae contained primarily glycerides but also had some PC and PE. Fat body from diapausing larvae contained primarily 16:0, 16:1, and 18:1 in a ratio of 1 : 1 : 2. Thus lipids of the southwestern corn borer do not reflect dietary lipids as closely as do other insects studied.

Phospholipid composition of the boll weevil,Anthonomus grandis boheman

Abstract When neutral lipids and phospholipids of the boll weevil, Anthonomus grandis, were studied during the larval-pupal ecdysis, the volume of lipids was found to increase until the pupal stage when it underwent a small decrease. The opposite was true for the phospholipids. The neutral lipids were high in palmitic, palmitaleic, and oleic acids; the phospholipids had large amounts of stearic and linoleic acids. Also, the composition of the phospholipids was qualitatively similar in the larval, pharate pupal, and pupal stages though the larval stage was marked by a predominance of phosphatidyl ethanolamine and a high concentration of linoleic acid in the phosphatidyl choline.

Constituents of the boll weevil, anthonomus grandis boheman—III lipids and fatty acids of subcellular particles of pupae

When phospholipids of newly-emerged adults of the boll weevil,Anthonomus grandis Boheman, were studied in detail, phosphatidyl choline and phosphatidyl ethanolamine were found to be the major phospholipids; sphingomyelin and cardiolipin were present in smaller amounts, and four other minor components were identified. Fatty acid analyses performed on the intact phospholipids and on the enzyme degradation products of phosphatidyl choline and phosphatidyl ethanolamine demonstrated that oleic and linoleic acids were the major fatty acids present in the glycerophosphatides; the sphingomyelin contained fatty acids in the range of 20–22 carbons.