Cl. Brubaker et al., OCCURRENCE OF TERPENOID ALDEHYDES AND LYSIGENOUS CAVITIES IN THE GLANDLESS SEEDS OF AUSTRALIAN GOSSYPIUM SPECIES, Australian Journal of Botany, 44(5), 1996, pp. 601-612
The presence of lysigenous cavities filled with terpenoid aldehydes (g
enerically termed 'gossypol') in most tissues of cultivated cottons an
d their relatives imparts natural resistance to a variety of insect, f
ungal, and bacterial pests. Deposition of terpenoid aldehydes in culti
vated cotton seed, however, renders cottonseed oils and protein meals
toxic to non-ruminant animals, including humans. Seeds of the so-calle
d 'glandless-seeded' Australian Gossypium L. species (Gossypium subgen
us Sturtia (R.Br.) Tod.) reportedly lack terpenoid aldehydes, and thus
may represent an important genetic resource in the development of cot
tonseed oils and protein meals free of these toxins. Information suppo
rting this assertion, however, is fragmentary and contradictory. To re
solve this, seeds of all known Australian Gossypium species were surve
yed chemically and anatomically. Immature lysigenous cavities were pre
sent in seeds of all 18 species. Lysigenous cavities of sect. Sturtia
and sect. Hibiscoidea Tod. seeds were unpigmented and invisible to the
naked eye, while pigmented, macroscopically visible lysigenous caviti
es occurred in all the sect. Grandicalyx (Fryxell) Fryxell seeds. HPLC
(high performance liquid chromatography) analysis revealed that sect.
Sturtia and sect. Hibiscoidea seeds did not contain detectable levels
of terpenoid aldehydes, but that sect. Grandicalyx seeds contained go
ssypol.