The Production Of Wheat-Aegilops Sharonensis 1S^sh Substitution Line Carrying Alien Novel HMW-GS

HMW-GS（High-molecular-weight glutenin subunits,HMW-GSs）is an important factor that affect wheat flour processing quality.Aegilops.sharonensis(S^shS^sh,2n=2x=14)which in has a novel HMW-GS with extremely large molecular weight.Our previous work found that Glu-1S^sh had the structural characteristics of high-quality subunits（especially long central repeat region）.According to the theory of quality processing model,this subunit has high quality structural characteristics and can be used for wheat quality improvement.On the basis of previous work,we further investigated agronomic traits,analyzed HMW-GS and chromosome composition,developed molecular markers and so on.Ph mutation gene and ⁶⁰Co-γradial were used in inducing homozygous material to produce 1S^sh substitution line.The main results are as follows.1.The plant height,tiller,awn length and other agronomic traits were investigated in18 derived lines with homozygous subunit compositions plus the presence of Ae.sharonensis HMW-GS.The results showed that the agronomic traits of 18 derived progenies were much better than those of amphidiploid and similar to female parent common wheat Liangmai 3（LM3）.However,there were some differences between them and their female parent LM3 in some traits.For example,the plant height of line No.66was generally lower than that of LM3.Flag leaves of line No.108 were longer and wider than those of LM3.The stems of line No.108 were thicker than those of LM3.Although the seed setting rate and thousand-kernel weight of line No.64 were close to those of LM3,the spikelet of line No.64 showed the same characteristics as Z636 and R7 at maturity,which made them easier to spontaneous abscission.2.Identification of 18 materials by ND-FISH cytology.The results indicated that the total chromosome number of 18 homozygous materials varied from 40 to 45 and the number of alien Ae.sharonensis S^sh chromosomes varying from two and eight.Most of the alien S^sh chromosomes in the derived lines were observed to be complete,and only a few of them were broken.Chromosome deletions mainly occurred on 1A,1B,3B,4B,7B,1D,3D,4D,5D,6D and 7D.Most of chromosome deletions appeared on B and D chromosomes.3.We developed four pairs of molecular markers that could specifically recognize1S^sh chromosome based on the published sequences of Aegilops and CS.Two pairs of them could specifically detect 1S^shL and the rest of two pairs could specifically detect 1S^shS.These four pairs of molecular markers can be used in the identification of 1S^shh chromosome and 1S^shL translocation.4.The line 66-9-17 was treated with ⁶⁰Co-γrays in order to generate 1S^shh chromosome substitution or translocation lines from M1 and its offspring.This mutagenesis failed to create translocation lines.It was presumed that M1 seeds were shrunk and failed to germinate due to the high dose of radiation and the selection of parent materials.5.Homozygous materials 66-9-17 and 66-17-52 were selected for hybridization with CS ph1b to induce 1S^sh substitution or translocation lines by Ph chromosome pairing genes.Two chromosome substitution lines of 1S^sh（5D）were successfully identified from the F2plants of hybrid progenies.These two substitution lines can be used for the subsequent production of 1S^sh translocation lines carrying exogenous HMW-GS gene.