The estimated 1C genome size of H. annuus is ∼3.3 pg of DNA (Bennett and Leitch, 2010). The two diploid annual parents used in the present study exhibited similar values, as HA 89 and HA 434 were measured at 3.45 pg and 3.60 pg, respectively (Table 2). The average 1C genome size among the 18 H. tuberosus accessions was 14.52 pg, higher than the previously reported value of 12.55 pg (Bennett and Leitch, 2010).