Seasonal Variations in the Emission of Volatiles by Cotton Plants Growing in the Field 1 , 2

Abstract

The volatiles emitted by growing cotton, Gossypium sp. in the open field were collected daily during June to September 1957 by pulling an air stream through a porous polymer and then desorption with pentane. From analysis by GLC and GLC-MS, a total of 70 compounds was identified, only 15 of which were also found in cotton bud essential oil. The amount of total volatiles collected reached a maximum in late July and early August when the cotton plant squaring and flowering was highest. Then production decreased, to some degree with continued fruit set and more rapidly with approaching senescence. Although the sex pheromone of the boll weevil is a more powerful attractant than the plant for this insect, the plant may play some role in its migration.