苗期筛选结合室内加代快速创制紫花苜蓿耐盐碱新种质OA

To accelerate the breeding of salt-alkali-tolerant alfalfa(Medicago sativa L.)varieties,in this study 19 alfalfa germplasms were used to establish a seedling-stage screening system for identifying salt-alkali-toler-ant materials.By combining generation breeding,salt-alkali-tolerant alfalfa germplasms were rapidly propa-gated to obtain the first generation hybrid(F1),which were subsequently evaluated for salt-alkali tolerance.The results showed that two-week-old alfalfa seedlings treated with 0.1 mol·L-1 Na+(NaCl∶NaHCO3=1∶1,pH=8.5)for 72 h could be effectively used to screen salt-alkali-tolerant individuals.Evaluation of 19 alfalfa germplasms at the seedling stage revealed that cultivars'WL-168HQ''Galaxie Max'and'Bara416'exhibited significantly higher salt-alkali tolerance than the others.By adjusting the light quality ratio,the FCL5 light con-dition(450-465 nm(white light)66.67%,450-480 nm(blue light)6.67%,615-650 nm(red light)26.66%)was identified as optimal,which supported healthy growth and high induction efficiency.Under FCL5 condition,110 elite salt-alkali-tolerant plants were subjected to flowering induction and open pollination to produce F1 half-sib family seeds.Evaluation of six F1 half-sib families demonstrated that the proportions of salt-alkali-tolerant plants in'Octane''Bara416'and'ZN-CT25'families were significantly higher than those of unselected commercial cultivars.This study provides technical support and valuable germplasm resources for the breeding of new salt-alkali-tolerant alfalfa varieties.