Self-incompatibility of Brassica is regulated by the S locus, which co
ntains several genes including SLG and SRK. We found that both SLG and
SRK genes were located at an approx. 80-kb MluI fragment in an S-9 ha
plotype of B. campestris. Therefore, we cloned this MluI fragment into
a BssHII site of the Pl-derived artificial chromosome (PAC) vector. T
he utility of the direct cloning method is discussed in this study. (C
) 1997 Elsevier Science B.V.