02179naa a2200229 a 450000100080000000500110000800800410001902400350006010000200009524501060011526000090022152015070023065000110173765000140174865300170176265300210177965300140180070000200181470000190183470000190185377300770187221251442020-09-28       2013    bl uuuu     u00u1 u    #d7 a10.1007/s10722-013-9990-32DOI1 aCLARINDO, W. R.  aFollowing the track of "Híbrido de Timor" origin by cytogenetic and flow hes.h[electronic resource]  c2013  aThe supposedly first plant of the coffee cultivar ??Hı´brido de Timor?? (HT) was found in 1927, being denoted as HT CIFC 4106. According to different researchers, this plant originated from a natural interspecific hybridation between Coffea arabica (4x = 44) and Coffea canephora (2x = 22). FromHT CIFC 4106, other HT accessions were obtained and employed to establish germplasm banks in some countries. As HT has been widely used in Coffea breeding programs, this study aimed to characterize different HT accessions with regard to ploidy, nuclear DNA content and base composition. Based on these data, the ploidy of HT CIFC 4106 was determined, suggesting that this accession is an allotriploid formed from reduced reproductive cell of C. canephora and of C. arabica. All HT CIFC 4106 plants exhibited the same 2C-value, AT% and chromosome number, showing that vegetative propagation has enabled the multiplication and germplasm conservation of this cytotype since 1927. Further five analyzed HT accessions showed distinct nuclear 2C-value and AT%. Since HT CIFC 4106 has been considered the first HT, it is suggested that aneuploid reproductive cells of this HT originated the other plants. Considering that HT accessions are used in the development of C. arabica cultivars, the findings of this study are important for the design of strategies to obtain new cultivars for breeding programs. Moreover, these data represent the first step to understand the origin and genome evolution of the HT.  aCoffea  aCytotypes  aAllotriploid  aBase composition  aKaryotype1 aCARVALHO, C. R.1 aCAIXETA, E. T.1 aKOEHLER, A. D.  tGenetic Resources and Crop Evolutiongv. 60, n. 8, p. 2253 - 2259, 2013.