A. Stoilova, Hr. Meluca
Abstract. The new cotton varieties Rumi and IPK Nelina were tested in 2005–2010. Rumi variety resulted from the crossing of the Bulgarian breeding line 268 (Garant X Progress) to the American variety Deltapine 20. The Progress variety was obtained after the interspecific hybridization G. hirsutum L. G. barbadense L. IPK Nelina variety resulted from the crossing of the Bulgarian variety Perla-267 (Garant X Progress) to the Romanian line T-073. Rumi variety had higher productivity than the standard cultivars – Chirpan-539 (for earliness and productivity) and Avangard-264 (for fiber quality) and other valuable properties such as finer and longer fiber than that of Chirpan-539, also lower content of short fibers and nep. In fiber quality it was closer to Avangard-264. In the state variety testing, Rumi variety exceeded both standards in seed cotton yield by 8.3 %, it exceeded Avangard-264 in fiber yield by 12 % due to higher lint percentage. IPK Nelina variety had high productivity and high lint percentage of the fiber. In the state variety testing, in seed cotton yield it was aligned with the standard cultivars, but in fiber yield was superior to Chirpan-539 by 2.6 % and to Avangard-264 by 8.8 %. These new varieties were approved by the IASAS (Executive Agency for Variety Trials, Approbation and Seed Control) in 2011 (Rumi) and 2012 (Nelina) and protected with certificates.