Variation of nitrogen use efficiency of Triticale in genotype and its evaluation

The nitrogen use efficiency and the correlative indexes of 31 Triticale cultivars were investigated at the tillering, jointing and heading stages under low and normal nitrogen supplies based on pot experiment. The results show that the nitrogen use efficiencies are different for the Triticale genotypes under the two nitrogen levels. The variation coefficient of Triticale at the heading stage is bigger than that at other stages, which is 19.07% under the low nitrogen level and 19.50% under the normal nitrogen level. The Triticale cultivars can be divided into three genotypes, high nitrogen use efficiency genotype, low nitrogen use efficiency genotype and the middle genotype. The high nitrogen use efficiency genotypes of Triticale are CIxt82, PI429186 and PI429228, and the low nitrogen use efficiency genotypes are CIxt74, CIxt75, CIxt76, PI428955, PI587238 and PI587241. The plant height and shoot biomass of the high nitrogen use efficiency genotypes are higher than those of the low nitrogen use efficiency genotypes. The plant height and shoot biomass are significantly correlated with the nitrogen use efficiency, which can be used as the indirect index to evaluate nitrogen use efficiency of Triticale.