A Preliminary Study on Introducting wheat Dwarfing Genes Into Octoploid Triticale

Li Xiaomei;Yan Yurui

dwarfing gene;;triticale

Thirty crosses were made in a NC Ⅱ design with six octoploid triticale varieties(2n=56) as female parents and five dwarf wheat varieties (2n=42) as male parents.Plant heights of F1 and F2 plants were measured.Parameter D(degree of dominance)and R(reducing ability of plant height) were calculated from F1 data.Frequency distibutions of plant height in various F2 populations were studied with reference of dwarfing genes involved.The results are summaried as follows: 1. The D and R values of the various dwarfing genes under the genetic background of AABBDDR could be arranged in a decreasing order as:Rht 10>Rht3>Rht1 Rht1 Rht2 Rhty>Rht1 Rht2. 2. The actual plant height reduced by the preasance of any dwarfing gene was nagattively related to the original plant height of the octoploid triticale variety used in crosses. 3. The dwarfing genes have normal effect on reducing plant height of triticale in F2 populations.Rht10 and Rht3 gene show double-peak distrbution while Rht1 Rht2 and Rht1Rht2Rhty show normal distribution in F2. 4. It's more effective to select dwarf triticale in BCl than in F2.And the dwarfing gene in common wheat could be introducted into octoploid triticale by direct triticale-wheat cross and backcross to triticale.