不同基因型大麦苗期对低氮胁迫的生物学响应

Biological responses of different-genotype barleys to low nitrogen stress at seedling stage

采用溶液培养试验的方法,对6个不同基因型大麦品种苗期耐低氮性状指标进行了研究。结果表明:单株吸氮量、根干重、地上部干重、植株干重、分蘖数和根长在品种间存在极显著差异;不同供氮水平对根长以外的各性状都有极显著的影响;各相对性状也存在不同程度的基因型差异,相对分蘖数>相对地上部干重=相对植株干重>相对根干重>相对单株吸氮量>相对根长>相对氮素生理利用效率>相对株高。相关性分析表明:单株吸氮量和苗期各干重指标间互呈极显著正相关关系;相对单株吸氮量、相对株高和苗期各相对干重指标间互呈极显著相关关系。

Six barley varieties were used as test materials and characters of seedling-stage barleys with different genotypes were studied under low nitrogen stress by hydroponic culture to get simple and effective indices of screening low-nitrogen tolerance. The results showed that there were very sig- nificant differences among the varieties in nitrogen uptake per plant, tiller number, root length and dry weights of roots, aerial part and plant. Nitrogen-supply levels had very significant effects on their characters except root length. Also there were differences in relative characters among different genotypes,and the descending order was relative tiller number〉relative dry weight of aerial part = relative dry weight of plant〉relative dry weight of roots〉relative nitrogen uptake per plant〉relative root length〉relative nitrogen utilization efficiency〉relative plant height. The correlation analysis indicated that the nitrogen uptake per plant and all the dry weight indexes at seedling stage mutually presented a very significant positive correlation, and so did the relative nitrogen uptake per plant, relative plant height and all the relative dry weight indexes at seedling stage.