低氮胁迫下大麦苗期株高和根长的遗传特性

Genetic Characters of Plant Height and Root Length of Barley at Seedling Stage under Low-nitrogen Stress

为指导大麦耐低氮育种,以耐低氮大麦材料BI-04与低氮敏感材料BI-45衍生的F3群体为供试材料,利用主基因+多基因混合遗传模型,对低氮胁迫下大麦苗期的株高和根长性状进行了遗传分析。结果表明,低氮胁迫下,F3群体株高表现为B-4遗传模型,即2对主基因的等加性遗传模型,遗传率为30.99%,说明选育株高性状可以在相对较早的世代进行。F3群体根长则表现为A-0遗传模型,即无主基因遗传模型,说明选育根长性状需要在较晚世代进行。

To provide guidances for low-N tolerance of barley breeding, a F3 population consisting of 198 lines,which was derived from the cross of low-N tolerance cultivar BI-04 and low-N sensitive eulti- var BI-45,was used to estimate the inheritance of plant height and root length of barley at seedling stage under low-nitrogen stress by using the major gene plus polygene mixed inheritance model. The results showed that the plant height of barely seedlings was genetically controlled by the genetic model B-4 （two major genes with equal additive effects） ,the heritability value of major genes for plant height was 30. 99%, while the root length was genetically controlled by the genetic model A-0 （no major gene）. So it was indicated that the plant height could be selected in early generations. Finally, the strategy of genetic analysis for breeding new barley varieties with low-nitrogen tolerance was dis- cussed.