Construction and characterization of a deep-coverage carrot (Daucus carota L.) BAC library

CAVAGNARO, P. F., CHUNG, S.-M., SIMON, P. W.

San Diego, California, USA

Conferencia; Plant and Animal Genome XVI Conference; 2008

The first carrot (Daucus carota L.) BAC library was constructed using imbred line B8503, which is nematode-resistant and accumulates carotenes in its roots. The BAC library consists of 92,160 clones comprising 22.4 haploid genome equivalents based on a genome size of 473 Mb/1C. Upon the analysis of 761 randomly selected clones more than 96% contained inserts. The average insert size was 123 kb, ranging from 20-370 kb, with 70% of the clones having inserts larger than 100 kb. End sequences from nearly 700 BAC clones were obtained and queried against the SwissProt and NCBI databases and significant hits were sorted according to putative function. Sequences similar to retrotransposons conformed the major category of the data set. In addition, we have identified BAC clones for several mapped genes/markers associated with important root traits, including Mj-1 nematode resistance, Rs sugar type, carotenoid QTL and carotenoid and phenyl-propanoid biosynthetic genes. The carrot BAC library is suitable for physical mapping, map-based cloning and genome sequencing and represents a valuable genomic tool for carrot breeding.