Abstract: To obtain the barley germplasms with low nitrogen tolerance for breeding, 19 barley landraces from Shanghai region were selected to screen and identify the low nitrogen tolerance. A hydroponic experiment was conducted to evaluate the low nitrogen tolerance of barley at seedling stage under two environments of normal nitrogen supply and low nitrogen stress, taking root length, plant height, tiller number, root dry weight and shoot dry weight as the evaluating indices. The ANOVA analysis showed that there were extremely significant differences between the two nitrogen supply levels and among different barley landraces, and there were also extremely significant interactions between nitrogen levels and barley landraces. The coefficient of variation indicated that the tiller number and dry weights had high variation coefficients and were more suitable for screening barley landraces with low nitrogen tolerance, while the plant height had low variation coefficient and was not a suitable screening index. The correlation analysis suggested that there were extremely significantly positive correlations between dry weight and other indices under normal nitrogen supply, and the trend was similar under low nitrogen stress though its correlation was some lower. Based on the importance of biomass for low nitrogen tolerance evaluation, we further compared shoot dry weight between normal nitrogen supply and low nitrogen stress, and the t -test revealed that five barley landraces (B929, B942, B945, B968 and B974) had the low nitrogen tolerance, meanwhile this criterion was more precise for evaluation of low nitrogen tolerance than the relative value. Furthermore, we investigated the correlations between shoot dry weight and nitrogen uptake or utilization related traits, and found that the latter two traits should be considered together for evaluation of low nitrogen tolerance in barley.

Key words: Barley, Low nitrogen stress, Screening index, Dry weight

CLC Number: 

• S143.1

• S512.3

• S326