Agronomic Characters And Molecular Markers Detection Of Wheat-Thinopyrum Derived Lines

The sources and varieties of wheat relatives are rich and diverse,and contain many beneficial genes.Among them,Thinopyrum is cold-tolerant,drought-resistant,salt-tolerant,powdery mildew,yellow dwarf,rust and other diseases.It is a close relative plant that is widely used in wheat breeding.There have been many reports on the research of transferring the excellent genes of Thinopyrum into common wheat.However,the excellent genes of Thinopyrum have not been fully developed and utilized so far.The wheat parental crosses can discover more excellent genes of Thinopyrum or excellent allelic variation of known genes.Therefore,we need to continue to discover and use the excellent genes of Thinopyrum,and introduce them into wheat to provide important materials and information for wheat breeding improvement.In this study,morphological markers,cytological analysis and molecular labeling techniques were used to analyze wheat-Thinopyrum intermedium derived materials and wheat-Thinopyrum ponticum derived materials to reveal the genetic characteristics of these materials.The research and utilization of Thinopyrum provides more extensive resources.The results are as follows:1.Agronomic traits of wheat-Thinopyrum intermedium:Field agronomic traits survey results: effective tillers: the largest range of variation,the coefficient of variation 32.4%,the most effective tillers of Zhong 499 in the material,the average value is 19.6;Spikelet: the smallest range of variation,the coefficient of variation 11.7%,Zhong199-200 in the material The average spikelet number is the most,26.2;Plant height: coefficient of variation is 13.3%,the average plant height of Zhong 483 in the material is up to 131.2cm,the lowest is Zhong 526,73.2cm in the material;Panicle length: coefficient of variation 16.7%,The average ear length of Zhong 199-200 in the material is the highest,21.2 cm,and the lowest is Zhong 479 in the material;The coefficient of variation of the thousand-grain weight of all materials is 17.9%,the variation range is 20.6-37.8,of which Zhong 209 has the highest thousand kernel weight(37.8 g).The statistics of setting rate showed that the setting rate of all the materials varied from 20.6% to 42.0%,with the average setting rate of Zhong 497 being the highest.2.Chromosome number and GISH analysis of wheat-Thinopyrum intermedium derived materials:Observation results showed that there were 5 materials(Zhong 209,Zhong 213,Zhong 515,Zhong 526,and Zhong 199-200),the number of chromosomes in the root tip cells was 2n = 42,accounting for 29.4% of the total;There are 2 materials with 2n= 54(Zhong 479 and Zhong 481),and 2 materials with 2n = 55(Zhong 485 and Zhong 499),accounting for 11.8% of the total number of materials;Materials with root tip cell chromosome number 2n = 56 are 8(Zhong 483,Zhong 487,Zhong 489,Zhong 493,Zhong 495,Zhong 497,Zhong 201 and Zhong 193-194),accounting for 47.1% of the total number of materials.In situ hybridization of 2n = 42 materials showed that the materials with 2n = 42(Zhong 209,Zhong 213,Zhong 515,Zhong 526,Zhong199-200)contained 40 wheat chromosomes and 2 Thinopyrum intermedium chromosomes,respectively,and identified as wheat-Thinopyrum intermedium substitution lines.3.Detection and analysis of molecular markers of wheat-Thinopyrum intermedium derived materials:The markers barc169,gwm135,gwm157,gwm608,gwm642,wmc144,and wmc27 all contained specific bands of Thinopyrum intermedium in the 17 derived materials identified,indicating that these materials all contain genetic material of Thinopyrum intermedium.Among them,5 substitution lines were found in the bands that contained Thinopyrum intermedium specific bands,and the most markers were located on the wheat 5B chromosome,indicating that these 5 materials contained Thinopyrum intermedium specific markers,and there were 2 out of 5substitution lines.The chromosomes were replaced,it is likely that some homologous chromosomes of Thinopyrum intermedium replaced the 5B chromosome in wheat.4.Agronomic traits and molecular cytology analysis of the derived material of wheat-Thinopyrum ponticum hybrid offspring:According to the results of field trait measurements: the highest plant height of the wheat-Thinopyrum ponticum reached 124.6cm,followed by Keyu 818,Lankao Aizao 8,Puyan 58,and the lowest was Aikang 58;Wheat-Thinopyrum ponticum has the most,with an average value of 22.4,followed by Aikang 58,Keyu 818,Lankao Aizao 8 and Puyan 58;In terms of panicle length,Lankao Aizao 8 is the longest,with an average value of 11.6cm,followed by Keyu 818;In terms of grain number per spike,Thinopyrum ponticum had the highest number of spikes and the average value was 55.2,Puyan 58 was the least and the average value was 47.6.Using the apical somatic cell chromosome counting method,we know that the number of chromosomes of Puyan58 is 2n = 42.Using genomic in situ hybridization technology,it is shown that Puyan58 has40 chromosomes from wheat and 2 chromosomes from Thinopyrum ponticum,which is a wheat-Thinopyrum ponticum substitution line.Using molecular marker technology,suggested that the two replaced chromosomes may have come from the fifth homologous group of Thinopyrum ponticum.