Studies On The Perennial Utilization Of Heterosis Between Sorghum And Johnson Grass And The Analysis Of SSR Markers

With the autotetraploid sorghum line "Sishentian", Johnsongrass (Sorghum. halepense) and their hybrid separation generation F₂ and F₃, the difference of their heredity was analyzed. The relationship between "Sishentian" and Johnson grass was detected by SSR. Two Segregation populations F₂, F₃ were detected by SSR, and main agronomic traits of these populations were analyzed for Perennial Heterosis. The results were summarized as follows:1.167 SSR primers and two sorghum lines were used to comparatively analyze the relationship of autotetraploid sorghum and Johnson grass on Polyacrylamide Gel Electrophoresis Systems in this study. The mainly result was that there was much difference between autotetraploid sorghum and Johnson grass, which was imbalance in chromosomes. And there was high level frequency similar location in some chromosomes, and high level frequency of difference location.2.The segregation of heterosis in F₂ and F₃ population built by Sorghum and Johnson grass hybrid was studied in the molecule genetic characteristics of heterosis by detecting SSR markers. The result showed that the variation in F₂ and F₃ population was in same level in molecule genetic characteristics, and there were no distinct differences between F₂ and F₃ population.3.The main agronomic traits of F₂,F₃ populations were investigated including Stem high, Ear length, Ear weight, Ear class, Cob weight, Nervation class, and tilling. The result showed that the variation in F₂ and F₃ population was in the same level on morphological characteristics. There was no distinct difference in variation of F₂ and F₃ population morphological characteristics. But after the selecting to F₃ population, the F3 segregation population kept higher level in the means of the morphological characteristics than F₂ population. By analysis the relationship between heterosis and selecting quantity trait, the result showed that the main stem high and leaf length had strong direct effects on per plant, on yield per unit area, the variation in seed setting had stronger relationship to the heterosisalthough the direct effects were not prominent.