Submitted to: World Cotton Research Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 9/12/2007
Publication Date: N/A
Technical Abstract: An important factor promoting variation in natural populations is the constant changes in the micro-environment surrounding the population. This variation in the micro-environment is due to both naturally occurring and artificially induced environmental factors. These same factors influence intentionally derived populations including varieties. Over time the plants making up a variety can diverge often changing to adapt to the environment in which they are grown. Some of these changes should be positive and if they can be detected, used to create new varieties superior to the source variety. It is known that selection within an existing cotton variety can produce progeny that are superior to the original variety. Some of the traits that have been selected include tolerance to disease, salinity and drought, earliness and fiber properties. This process can be accelerated if the selection can be carried out on a part of the seed with the remainder of the seed being planted and used to produce the next generation. The process can also be improved if enzyme, biochemical or molecular markers can be identified and used to detect the desired genotypes. Using this combination of methods, scientists at the Institute of Genetics and Plants Experimental Biology developed new elite lines that are currently being tested in the Uzbek State Variety Trials. The first line, Shodlik-9, is superior to its source variety, Bayaut-2 for Verticillium wilt and agronomic traits. Fiber analyses at the Uzbek State Testing Lab and StarLab (a private US testing lab) showed that Shodlik-9 was superior to FM 832, SG 747 and Namangan 77 for fiber length, and it was similar to FM 832 and Acala 1517 for strength, 2.5 % and 50% span length. Two other lines (L2 and L3) are currently being evaluated for Verticillium wilt resistance and agronomic traits. The lines are significantly earlier than US varieties (109 to 113 days to maturity) with comparable yields. These new lines offer a valuable source of new germplasm not only for Uzbekistan, but also for other countries worldwide.