Analysis Of Agronomic Traits Of EMS-Induced Wheat-Psathyrostachys Huashanica Additional Mutant

Psathyrostachys huashanica（2n=2x=14）is a diploid plant in the tribe Triticeae.It is resistant to wheat endemic diseases such as head blight,stripe rust,powdery mildew,take-all and yellow dwarf virus,and adaptable to cold,saline-alkali,drought and poor soil environment and is a wild relative species of crops with great value in crop variety improvement,and can be used as a new stress resistance and disease resistance gene donor（Ns genome）of wheat.The wheat-Psathyrostachys huashanica alien addition lines derived from distant hybridization between wheat and Psathyrostachys huashanica were important genetic resources in wheat breeding.However,the alien addition lines with intact alien chromosomes not only had poor genetic stability,but also could not avoid the adverse effects of alien chromosomes,so it was difficult to be directly applied in production.In order to study and utilize the excellent characters and genes of Psathyrostachys huashanica,the research used EMS to mutagenically treat the alien disomic lines of ordinary wheat-Psathyrostachys huashanica 1Ns-7Ns that have been created,and tracked and identified the mutagenic M₁ and M₂ generation groups through agronomic trait investigation and in situ hybridization analysis,in order to obtain the stable wheat-Psathyrostachys huashanica translocation lines,and the main research results are as follows:1.Chromosomes in root tips and pollen mother cells of wheat-Psathyrostachys huashanica 1Ns-7Ns disomic addition line were identified by Gish.The loss rate of exogenous Ns chromosomes of wheat-Psathyrostachys huashanica 2Ns,3Ns,4Ns,6Ns,and 7Ns addition lines exceeded 50%,and the chromosome loss rate of 4Ns and 7Ns additional lines of Ns were as high as 80%,and the number of seeds lost from 2 exogenous chromosomes exceeded 50%of the total number of seeds of the corresponding materials.2.The wheat-Psathyrostachys huashanica 1-7Ns alien addition lines were treated with1.0%EMS,and the plant height of 26 mutants of the M₁ generation mutation population were significantly better than those of the untreated additional line control and wheat parent7182,the panicle length of 8 were significantly better than those of the control and wheat parent,the number of spikes per plant of 3 were significantly better than the control and wheat parent,and the number of grains per spike of 4 mutants were significantly better than those of the control and wheat parent.The yield traits except Thousand-grain weight of 1mutant was significantly better than those of the control and wheat parent 7182 and the thousand-grain weight of 3 were significantly better than those of the control and wheat parent 7182.3.Changes of main agronomic traits of M₁wheat-Psathyrostachys huashanica 1-7Ns addition lines under EMS treatment:The emergence rate and germination rate of seeds of wheat-Psathyrostachys huashanica 1-7Ns addition lines treated with 1.0%EMS decreased significantly.The plant height of M₁ mutant plants was generally shorter than that of the untreated control ad-line,and the mutants of the 3Ns-addition line,4Ns-addition line,5Ns-addition line,and7Ns-addition line all had positive mutations in the main yield traits,among which the positive mutation rates of the spikes per plant,spikelet number and grains per spike after the EMS treatment of 4Ns and 5Ns addition lines exceeded 40%,and the excellent variations were more;the main agronomic traits of 7Ns addition line changed greatly after EMS treatment,and the phenotype of the mutant population showed diversity,but the positive mutation rates of spike length,grain number per spike and 1000-grain weight exceeded 20%.After the EMS treatment of 1Ns,2Ns and 6Ns addition lines,the plants became shorter,and the main yield traits were worse than those of the control.4.Using 1.0%EMS to treat seeds of wheat-Psathyrostachys huashanica 1-7Ns alien addition lines,the chromosomes of root tip cells of M₂ generation of each addition lines were analyzed by GISH analysis,and 1 binary translocation line and 1 monomeric translocation line were screened from the M₂ mutants of wheat-Psathyrostachys huashanica4Ns addition line 24-3-1,which verified the feasibility of creating translocation lines by treating wheat seeds with high concentration EMS reagent.