Identification And Evaluation Of Germplasm Resources Of Hordeum Revisubulatium

Hordeum brevisubulatium is a perennial herb of the grass family barley.Its stems and leaves are soft,palatability is good,nutrition is rich,and it is an excellent forage.Wild barley has developed roots,strong adaptability,cold resistance,drought resistance,salt and alkali resistance,strong tillering and regeneration ability,high yield,good production performance,and high economic utilization value.In this study,197 wild barley germplasm resources from 5 different sources were selected as the research object,and the phenological period of these materials in Hohhot was observed.12 agronomic traits and stress resistance of these materials,including grass yield,seed yield,plant height and tillering number,were analyzed and evaluated,and high-yielding germplasm resources were selected to provide high-quality provenances for wild barley breeding.The results of this study can lay a solid foundation for the breeding of excellent new wild barley varieties.The main results are as follows:（1）All the 5 Hordeum brevisubulatium materials returned to green in mid-March,and the local resources returned to green in 202002 and 202003,which were the wild germplasm materials of Hohhot Current and Shenggeying,respectively.The growth period and growing days of 202004 were the longest,140-150d and 258d,respectively.（2）Analysis of 12 agronomic traits showed that genetic variation within Hordeum brevisubulatiumpopulation was greater than among populations.The variation coefficients of agronomic traits ranged from 9.11%to 53.39%.The variation coefficients of 12 major agronomic traits were in the following order:seed yield>Dry weight per plant>Number of tillers>Leaf length>Small number>Spikelet length>Spikelet number>Number of blades>Blade width>Plant height>Number of sections.（3）The salt-alkali tolerance evaluation results of Hordeum brevisubulatium seeds during germination showed that the suitable range of salt tolerance to single salt stress（Na CL）was<At 60m M,double salt stress（Na CL:Na HCO₃）was<120m M.The salt tolerance limit concentration of Hordeum brevisubulatium seeds under single salt stress was above 180m M,and the salt tolerance limit of wild barley seeds under double salt stress was 150m M,and the salt tolerance limit of wild barley seeds under single salt stress was higher than that under double salt stress.（4）The results of simulated drought stress treatment showed that the germination rate of wild barley seed（64%）was not significantly different from that of control group（66.7%）under low concentration PEG-6000（10%）treatment,but the germination potential was higher than that of control group.With the increase of PEG-6000 concentration,the drought stress increased gradually,and the germination rate of seeds decreased obviously.When PEG-6000 concentration reached 40%,all Hordeum brevisubulatium seeds lost germination ability and germination rate was 0.（5）Principal component analysis showed that the six main traits that could be used for Hordeum brevisubulatium evaluation were:seed yield>dry weight per plant>reproductive branch number>plant height>spikelet number>leaf length from high to low.（6）A total of 10 high-yielding germplasm strains were selected in this study.Among them,3 strains in 202001,2 strains in 202002,1 strain in 202003,2 strains in 202004,and2 strains in 202005.