Two sources of resistance to bacterial wilt caused by Pseudomonas solanacearum E.F. Smith have been identified (Russell, 1978). The North Carolina type of resistance is expressed by derivatives of Louisiana Pink. The second type of resistance has been derived from Lycopersicon pimpinellifolium (PI 127805 A). The study was attempted to incorporate the above two reported sources of resistance into a single variety. F1's were developed through hand emasculation and pollination using Lycopersicon pimpinellifolium as male and 10 Carolina lines as females. Parental lines, F1's and F2's were grown in a wilt diseased field. This study indicated that there are separate gene systems responsible for resistance in the two sources of wilt resistance. On analysis of F2 data a 9:7 ratio was obtained which indicated that complementary and hypostatic recessive gene action was responsible for the combined disease resistance. The gene system in the Carolina type of resistance was designated as wr\1\wr\1\wr\2\^+^wr\2\^+^ and that in PI 127805 A as wr1^+^wr1^+^wr\2\wr\2\ where wr\1\ is hypostatic to wr\2\ and wr\2\ hypostatic to wr\1\^+^.
Literature cited:
Russell, C.E. 1978. Plant breeding for pest and disease resistance. 1st ed. pp. 190-193. Buddenworths, London.