Identification Of Stable Lines Derived From Hybrid Progeny Of Thinopyrum Intermedium And Common Wheat And Preliminary Study On The Reasons For Producing High-protein Lines

Common wheat(Triticum aestivum L.,2n=6x=42,AABBDD)is one of the most important rations for human life,with the economic development of China and the improvement of people’s living standards,people are paying more and more attention to the genetic improvement of wheat.However,wheat is currently suffering from severe abiotic stresses such as drought and temperature,as well as biological stresses such as diseases and insect pests,which result in an increasingly narrow genetic basis for wheat,severely restrict the improvement of wheat yield,disease resistance and quality breeding.In order to solve these problems,it is possible to consider introducing some excellent germplasm from wheat related species and plants through distant hybridization to improve the genetic diversity of wheat.This is very important for wheat genetic breeding,not only to broaden the wheat gene pool,but also sometimes directly applied to production practices.Thinopyrum intermedium is one of the most successful and widely used wild relatives for genetic improvement of wheat in China.Many of its valuable genes have been transferred to the wheat genetic background through distant hybridization,and a large number of new germplasm resources containing intermediate materials have been obtained.To study of some durable traits among these intermediate materials is favorable for wheat improvement and practice.In this study,the stable wheat lines TC,22w-031,22w-251,derived from the hybrid progenies of the Thinopyrum intermedium and common wheat,and the hybrid strains between TC and SY95-71,22w-156,22w-158,22w-160,22w-162 were used as materials by cytological identification by non-denaturing fluorescence in situ hybridization(ND-FISH),isolation and identification the composition of the high molecular weight gluten subunit and gliadin bands by SDS-PAGE and A-PAGE,and the quality determination by NIR grain analyzer.The main results were as follows:1.ND-FISH identification results showed that the wheat line TC has a reciprocal translocation between chromosomes 3D and 7B,and the translocation breakpoints takes place at the centromere.Thus line TC contains one pair of 3DS·7BS and one pair of3DL·7BL.The chromosome number of line 22w-031 was stable with 2n=44.ND-FISH indicated that the 4D chromosome was missing and a pair of St chromosomes and a pair of St-J~Stranslocation chromosomes were added.Line 22w-251 is a substitution line in which one pair of 4D chromosomes is replaced by one pair of the J chromosomes coming from Thinopyrum intermedium.Among the strains of hybrid progenies between TC and SY95-71,only 22w-158 has the same 3D/7B reciprocal translocation as TC.2.The investigations of agronomic traits showed that the line TC and 22w-031 were resistant to stripe rust.Compared with wheat parent,some differences of tested materials were found in plant height,spike length,spikelets perspike and 1000-grain weight.TC was significantly higher in spike length,spikelets perspike,and 1000-grain weight than its wheat parents;The number of spikelets in 22w-251 was significantly higher than that of the wheat parent,while the 1000-grain weight was significantly lower than that of the parent;22w-031 showed a higher plant height and significantly lower thousand grain weight than its wheat parent.3.The results of near-infrared grain analysis showed that the line TC was significant differences compared its parent CM107 and the hybrid strains of TC and SY95-71 in protein content,wet gluten content,sedimentation value,stabilization time and formation time,and the quality parameters of line TC reached the standard of medium and strong gluten wheat.4.The separation and identification of HMW-GS by SDS-PAGE and gliadin bands by A-PAGE showed that the no significant differences between the line TC and hybrid strains of TC and SY95-71.However,moreω-gliadin bands were found in line TC.In addition,ω-gliadin bands encoding by Glu-D1 site in 1DS chromosome was absence or silence in strain 22w-158,which has the same chromosome constitution with the line TC.All these results suggested that 3D/7B reciprocal translocation is not essential in processing quality of line TC.