Pigment glands

Structural and Genetic Variation of Natural Pesticides in Pigment Glands of Cotton (Gossypium)... 

The importance of pigment glands as sources of toxins in cottonseed was suspected early in the twentieth century. In 1915 Withers and Carruth ( showed that the toxicity of cottonseed to animals was due to the compound gossypol localized in pigment glands. 

The wild New World diploid cottons contain two TA patterns not found in other species. Ten of these 12 species contain only gossypol or gossypol and its methyl ethers in pigment glands of all tissues (12 ). Thus, the enzyme necessary for formation of TA quinones apparently is absent from green tissues in these species. 

Table I. Volatile Terpene Concentrations in Oil Collected from Pigment Glands of Calyxes of G.. hirsutum Acala SJ-1 ...

Table II. Percentage Distribution of Volatile Terpenes in Pigment Glands of Leaves of Cultivars and Texas Race Stocks of fi.. hirsutum and of . barbadense Seabrook Sea Island 12B2 ...

Table IV. Percentages of Methylation of Total Terpenoid Aldehydes in Pigment Glands of Various Gossypium Species and Hybrids with hirsutum...

Table V. Percentages of Raimondar in the Total Terpenoid Aldehydes from Pigment Glands of Gossypium Species and Their Hybrids with G.. raimondii...

We have also developed stocks that produce mostly raimondal in place of the normal TA in pigment glands. This was accomplished by making the triple-species hybrid [. hirsutum X (. arboreum X G. 

Cook was among the first to propose that the pigment glands of cotton might act as a repellant to the bollworm (266). 

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