Genetic Screening And Identification Of The Composition Of Newly Developed Triticale And Tritileymus Germplasm

Relative species such as rye and L.mollis have significant utilization value in wheat genetic improvement.The amphiploids developed by the cross between rye,L.mollis and common wheat not only has the ability of parental resistance to multiple diseases and stress tolerance but also can overcome the incompatibility of direct crosses between wheat and related plants,hybrid sterility,and other obstacles are essential bridges for introducing excellent genes from related plants into common wheat.It is also the primary material for creating and cultivating alien addition lines,alien substitution lines,and translocation lines.Clarifying the traits and genetic composition of these amphiploids will help promote their further use in wheat genetic improvement.This study identified the disease resistance,salt tolerance,agronomic characteristics of materials such as hexaploid and octoploid Triticale,and octoploid Tritileymus in the laboratory genomic in situ hybridization and fluorescence in situ hybridization technology analyzes its genetic composition and chromosome structure variation.The results obtained are as follows:1.Disease resistance identification results showed that hexaploid and octoploid Triticale materials are generally highly resistant to stripe rust and powdery mildew.Most of the octoploid Tritileymus and its progeny materials are highly resistant to stripe rust but highly susceptible to powdery mildew.The salt tolerance identification results show that different hexaploid Triticale materials have different responses to high salt stress.The aboveground and underground parts of plants are inhibited to varying degrees.Materials with better salt tolerance,such as L20190109,have been screened and identified.High salt stress has a more significant impact on the shoots of octoploid Tritileymus seedlings,and moderate salt stress has a specific promoting effect on its roots.2.Using rye genomic DNA as a probe,genomic in situ hybridization of 36 hexaploid Triticale materials showed that 35 materials contain 14 foreign chromosomes from rye,and 1materials contain 12 foreign rye chromosomes.Using oligonucleotide probe sets and rye DNA as mixed probes,FISH karyotypes of 36 hexaploid Triticale materials were identified.The comparison found that 4 materials found significant variations in chromosome composition,such as 2D chromosome substitution 2R chromosome and 6D chromosome replace 6A chromosome.In addition,on the chromosomes 2A,5A,6A,and 7A of the A group of hexaploid Triticale materials,the B group 2B and 7B chromosomes have a significant degree of structural variation.3.Using the genomic DNA of Psathyrostachys huashanica as a probe,the octoploid Tritileymus,and its self-progeny materials were identified by genomic in situ hybridization,and it was found that among the 18 materials,there were 6 and 9 materials with 2n=56chromosomes.The material contains 14 foreign chromosomes,and the chromosome composition of 14 materials varies greatly.Combined with the results of fluorescence in situ hybridization with oligonucleotide probes,it was found that the genomic composition of the offspring from Tritileymus was complex,and 9 materials lost 2-11 chromosomes in different numbers compared with octoploid materials.The identification of the genetic composition of wheat crops laid the foundation for its further utilization.