小黑麦氮利用效率基因型差异及评价

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

为小黑麦氮高效基因型育种提供依据,以31个代表不同遗传背景的小黑麦品种为对象,采用盆栽试验,设低氮和正常供氮2个处理,对小黑麦在分蘖期、拔节期和最佳刈割时期—抽穗期的氮素利用效率和相关性状指标进行研究。结果表明,小黑麦的氮素利用效率在低氮和正常供氮条件下都有较大的基因型差异,并在抽穗期时变异系数达到最大(低氮条件下变异系数为19.07%,正常供氮为19.50%)。根据小黑麦在两供氮条件下不同生育期的氮素利用效率可将小黑麦分为3个类型:氮高效利用基因型、氮低效利用基因型和中间类型,并由此确定氮高效利用基因型为C Ixt82、PI429186和PI429228,氮低效利用基因型为C Ixt74、C Ixt75、C Ixt76、PI428955、PI587238和PI587241。小黑麦株高与地上部生物量在两供氮条件下各生育期表现出氮高效利用基因型高于氮低效利用基因型的趋势。相关性分析表明,小黑麦株高和地上部生物量与氮素利用效率呈现较强的正相关性。因此,这两个植株性状可作为小黑麦氮高效利用基因型评价的辅助指标。

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.