Fiber properties of caducous bract hexaploid cottons.
Muramoto-H; Sherman-R; Ledbetter-C
Proceedings of the Sixth Cotton Dust Research Conference, beltwide cotton production research conferences, January 4, 1982, Las Vegas, Nevada. Wakelyn PJ, ed. Memphis, TN, The National Cotton Council of America, 1982 Jan; :78
The transfer of caducous bract (CB) trait from hexaploid to tetraploid cultivars and the fiber properties of the hexaploid cotton were studied. The purpose of the work was the ultimate development of a commercial cotton which would drop its bracts before the bolls opened. CB hexaploid cotton was developed by crossing Gossypium-hirsutum with Gossypium-armourianum. Three CB plants were isolated, two with 58 and one with 60 chromosomes. Fertility and yield were improved with each selection cycle. The average fiber length of the CB hexaploid ranged from less than 1 inch in the initial crops to a maximum of 1.12 inches after 6 years. The average fiber strength after 6 years of selection was considerably greater than the strength of commercial cultivars, as measured on the Pressley tester. The CB selections in 1975, 1980, and 1981 averaged 2.5, 3.94, and 3.67, respectively, on the Pressley index. The strength of the commercial varieties averaged 3.13 in 1980 and 2.99 in 1981. The average fiber fineness showed a wide variability. The micronaire unit readings were approximately 4.5. The CB selections showed fineness readings of 4.38 in 1980 and 4.78 in 1981. Two commercial varieties averaged 5.04 in 1980 and 4.73 in 1981. The authors conclude that selection for fiber properties in the CB hexaploid population is possible because of the variation still present in the population.
NIOSH-Grant; Biological-material; Cotton-fibers; Genetic-factors; Mechanical-tests; Tensile-strength
Proceedings of the Sixth Cotton Dust Research Conference, beltwide cotton production research conferences, January 4, 1982, Las Vegas, Nevada
Plant Sciences University of Arizona Plant Science Department Tucson, Ariz 85721