On the Linkage between a Gene Contracted and an Inhibitor of White-margined Flower in Pharbitis Nil

Abstract

1. There is found a gene Margined white 4 (M_r4) which links to polymorphic (p_y) and white flower (a₄), the recombination percent being about 28.5 with the former gene, about 33.3 with the latter one.
2. Margined white 4 (M_r4) is complementary to M_r1, M_r2 and M_r3 for the manifestation of white margined corolla.
3. These four genes for white margined belong respectively to four linkage groups, that is, M_r1 to contracted linkage group, M_r2 to accuminate one, M_r3 to pear one, and M_r4 to variegated one.
4. Three duplicate genes, Margined inhibitor 1 (M_r-i1), Margined inhibitor 2 (M_r-i2) and Margined inhibitor (M_r-i3) occur as inhibitors to modify white margined corolla into self-coloured one.
5. Margined inhibitor M_r-i1 links closely to contracted (c_t).
6. White flower (a₂) links to contracted with 44.4 percent recombination, to side reduced (s_r) with 41.8 percent one. The arrangement of these three genes on a chromosome may be as c_t-s_r-a₂.