G barbadense

G. herhaceum Levant cotton G. barbadense Sea Island cotton G. States, India, FSU ... 

Wendel, J. F. and Percy, R. G. 1991. Allozyme diversity and introgression in the Galapagos Islands endemic Gossypium darwinii and its relationship to continental G. barbadense. Biochem. Syst. Ecol. 18 517-528. 

TA in G. barbadense cotton. Analyses of TA in barbadense cultivars revealed five compounds not found in Upland or Asiatic cottons (12), These compounds were identified as the 6-methyl and 6,6 -dimethyl ethers of gossypol (Scheme 1 MG, DMG) and the 6-methyl ethers of hemigossypolone (Scheme 2 MHGQ) and of heliocides and " The latter two compounds, which are formed from ocimene and were given the trivial names heliocide B, and B. (Scheme 2 ... 

TA in wild cottons. Many wild cottons have TA contents similar to those of G. barbadense. Thus, 30-80% methylation of terpenoids and a predominance of ocimene-derived heliocides also occurs in anomalum. . bickii. . capitis-viridis. G. darwinii. lonoicalvx. G. tomentosum and G. sturtianum (121. In the latter two species, the TA quinone concentrations are much greater than the heliocide concentrations, indicating that very little ocimene or myrcene is formed in these species. 

Teroenes in G. barbadense and Upland race stocks. Different cultivars of Upland cotton have similar profiles of volatile terpenes, but barbadense and certain insect-resistant Texas race stocks of G.. hirsutum (15 - 17) have profiles different from the cultivars. 1. barbadense lacks myrcene, y-bisabolene and B-bisabolol, which are major components in cultivated Upland cotton, but it has greater concentrations of a-copaene (18 Table II). 

Constitutive tannins also may contribute to resistance. The resistant 6. barbadense cultivars have higher levels of tannins, especially in older leaves, than do susceptible 6. hirsutum cultivars (16). Also, the G. barbadense tannins appear to be more astringent, based on their antisporu 1 ant activities. Endodermal cells several millimeters back of the root tip also contain large amounts of tannin (53). Many attempted penetrations of the stele are aborted at the endocTermis, which forms a protective ring around the vascular cylinder. 

The effect of mercerization on tensile properties depends on the type of cotton tested. In one study six G. barbadense samples were slack mercerized and the breaking forces and tenacities of the fibers relative to their nonmercerized counterparts ranged from 88 to 122% and from 80 to 114%, respectively [314]. A larger change was found in the case of a G. 

Cottonseed oil (Gossypium hirsutum (American), G. barbadense (Egyptian),... 

Fig.l. Southern blots of genomic DNA probed with pghD12-l-and pghD 12-2-specific sequence fragments. ari>=G. barbadense Hir=G, hirsutum E= EcoR I H= Hindlll. Molecular size (kb) of DNA ladder is indicated on the left. 

C. is a good example for multiple-use crops fiber and seed oil and meal (other examples - linseed and - hemp). New world c. species of commercial importance are G. barbadense L. and G. hirsutum L., old world species are G. arboreum L. and G. herbaceum. 

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