Jx. He et al., The cytogenetics and fiber properties of an allohexaploid between Gossypium hirsutum and G-somalense, CHIN SCI B, 46(2), 2001, pp. 136-140
Cytogenetics and fiber properties were studied on the Gossypium hirsutumxG.
somalense F-2 hybrid and later generations. The cytological analyses of po
llen mother cells (PMCs) were made at meiotic metaphase I. The results indi
cated that the hybrid was a new allohexaploid, its chromosome number determ
ined as 2n=6x=78, and genome group as 2[(AD)(1)E-2]. Chromosomal configurat
ions of the hexaploid averaged 0.15 I + 38.72II + 0.11III + 0.02IV per cell
, 85.09% PMCs having 39 bivalents, and only 11.84% PMCs having I to 2 multi
valents, indicating that heterogenetic recombinations of chromosomes occurs
between (AD)(1) and E-2, nevertheless, the frequency is lower. The hexaplo
ids are self-fertile and the progenies remain the hexaploids, whose fibers
are light brown and have higher strength by measurement of HVI 900 system.
The fiber strength increases 42% than that of upland cotton variety. Theref
ore, it is possible for the hexaploid to be an important germplasm resource
to improve fiber strength of cotton.