**2. History and development of Uzbekistan cotton collection**

The past century of cotton production in Uzbekistan has developed well-established cotton research programs and distinguished cotton scientists who initiated and devoted themselves to collecting important materials for cotton research. As highlighted in previous reports [3; 8] the cotton germplasm collection initiative was began by Drs. N. I. Vavilov and F. M. Mauer in 1930 in the former Soviet Union. Subsequently, Uzbekistan cotton germplasm founder and leader Dr. A. Abdullaev and his group expanded this initiative and established a collection of Uzbekistan germplasm materials through the (1) coordination of scientific efforts of continu‐ ous selection of cultivated cotton varieties, (2) continuation of collecting and preserving wild cotton species and landraces from centres of origin during many scientific expeditions, and (3) germplasm exchange worldwide.

According to Abdullaev et al. [8], several expeditions to Central Asia, Afghanistan, China, India, Turkey, Iran, Korea and Japan to obtain germplasm were made during 1920-1930, Dr. N. I. Vavilov, P. M. Jukovsky and Dr. F. M. Mauer, and in 1950s Dr. D. V. Ter-Avanesyan. In later periods from 1974 to 1998, Dr. A. Abdullaev visited to Mexico, Peru, China, India and Sri-Lanka, Australia and Pakistan and obtained germplasm. These historic scientific expedi‐ tions enriched Uzbekistan collection with Old World (Afro-Asian and Indian) diploid cottons (*G. herbaceum* and *G. arboreum*), and a number of wild, exotic and cultivated tetraploid and diploid cottons around the world [8].

The Uzbekistan collection has been periodically enriched as a result of germplasm exchanges with collections worldwide. In the most recent exchanges within the framework of USDA-Uzbekistan Cooperation programs, approximately ~ 1000 *G. hirsutum* exotic and varietal accessions were exchanged with the US cotton germplasm collection [11; 12]. Annually, 100-120 cotton accessions from the collection of Uzbek Research Institute of Cotton Breeding and Seed Production (UzSRICBSP) are exchanged with world centres. During the period of 2001-2003, the Institute received 990 accessions from and sent 260 cotton accessions to the US cotton germplasm collection [7].
