Identification Of Wheat--Aegilops Variabilis Translocation TKL1 And Its Utilization On Genetics And Breeding

Sichuan common wheat landrace Kaixianluohanmai (abbrev. KL) has the gene phKL with a promoting effect on homoeologous pairing between wheat and alien chromosomes. The hybrid of KL with phlb mutant of wheat Chinese Spring (abbrev. CSphlb), KL*CSp/i/6, was obtained by using KL as the female parent. From the F2 progenies of (KL*CSphlb) x Ae. variabilis, a new wheat line TKL1, carrying genetic materials from Ae. variabilis and having chromosome number with 2n=42, was detected.The objective of this study is to analysize its genetic stability, to identify the alien genetic materials of TKL1 and to evaluate its utilization in genetics and breeding. The results as follows:During several years, TKL1 showed a consistent agronomic perforamance similar to regular wheat, while the tough glume of TKL1 was similar to Ae. variabilis. TKL1 had a stable chromosome number with 2n=42. During middle I of meiosis of pollen-mother-cell, these chromosomes showed normal pairing as common wheat. These results indicated that TKL1 was a stable wheat line in genetics. It was also proved by the same glutenin and gliadin patterns among different TKL1 plants.Tough glume, adult resistance to powdery mildew and new Glu-1 band indicated that some genetic materials of Ae. variabilis had been transferred into TKL1. The cytological data showed that TKL1 was a translocation involved in the missing of wheat chromosome arms 2DL and 3DS. C-banding indicated that TKL1 has translocation chromosome 2S1S/2DS. The chromosome arm 2S'S was derived from Aegilops variabilis. However, C-banding could not detect the translocation related to 3DS.In comparison with KL*Ae. variabilis, TKL1*A variabilis had significant higher level of chromosome pairing. This probably inferred that phKL gene of KL was also transferred into TKL1. The higher chromosome pairing level was caused by the action ofboth phKL and absent of 3DS with the suppressing gene Phi for homoeologous chromosome pairing. TKL1 could be used as a material or 'bridge tool' in wheat chromosome engineer.