All maize inbreds have been classified into heterotic groups based on pedigree information or combining ability. The Lancaster Sure Crop and BSSS heterotic groups are the most commonly used heterotic pair to developing commercial maize hybrids in central and southern Europe. One of the best middle late hybrids was that between B73 (BSSS) and Mol7 (Lancaster). In the present study, we analyzed the means of test cross grain yield, grain yield per se, ear length, number of grain rows, grain mass, cob diameter, kernal length, kernal width and stem rot of 19 maize inbreds derived from Mo 17 family. The Mo 17 derivative inbreds are characterized by divergence of all the above traits. Two of the 19 inbreds crossed with the B73-type inbred tester 568 had significantly higher grain yield (P<0.05) than the standard hybrid B73×SMol7. Germplasm unrelated to Mo 17 one, namely that originating from the domestic populations Vukovarski Zuti zuban and Zuti zuban, as well as that from the public-domain line N152 brought to the Mo 17 family a longer ear, a larger number of grain rows per ear and a higher potential for grain yield per se and in test crosses with B73 inbred line relative to Mol7.