[Analysis of genetic relationship between sorghum (Sorghum bicolor L. Mench) and johnsongrass (Sorghum. halepense L. Pers)].

Tetraploid sorghum (Sorghum bicolor L. Moench) line "sishentian" and Johnsongrass (Sorghum halepense L. Pers) were used to analyze genetic differences between Sorghum and Johnsongrass by SSR (simple sequence repeat) markers and cytogenetic methods. The SSR analyzed results indicated: (1) There were great genetic differences between sorghum and Johnsongrass, According to the different locus distribution, the chromosome linkage groups can be separated into two groups: High differences group and low differences group. (2) Cytogenetic analysis revealed that the parents and their hybrid are irregular tetraploid genetic populations; The chromosome configuration at MI were mainly bivalent and quadrivalents in sorghum, Johnsongrass and their hybrid; there were 17.00, 15.23, 15.83 bivalents and 0.95, 2.15, 1.60 quadrivalents in hybrid, sorghum and Johnsongrass respectively; The results of SSR and cytogenetic analysis demonstrated that the genome of Johnsongrass and Sorghum are homologous in a certain extent. The hybrid can not be steadily hereditary as double diploid.