论文部分内容阅读
采用苗期营养液水培与全生育期田间种植的方法,以相关形态、产量、生理指标作为评价依据,对5份不同基因型小麦的耐低氮性进行了比较。结果表明:相对于正常供氮,低氮胁迫条件下,小麦苗期株高降幅12%~29%、叶片干重降幅11%~57%、根冠比增幅4%~52%、叶片氮素含量增幅62.6%~91.7%,叶片氮素累积量降幅47%~71%。成熟期小麦的株高降幅21%~26%、每株有效穗数降幅20%~41%、小麦产量降幅26%~69%。这表明,小麦苗期株高、叶片干重和氮素累积量的下降可限制小麦产量的形成。可以认为,不同基因型小麦苗期与成熟期的耐低氮性存在一定联系,各基因型小麦在耐低氮性上存在差异,可以在苗期进行耐低氮性初步鉴定。通过比较、鉴定小麦苗期和成熟期的不同性状,能够挖掘出耐低氮种质材料。依据供试材料的特征,结合各自的形态和产量生理指标上的差异,对耐低氮的可能机理进行了讨论。
The methods of hydroponic culture at seedling stage and field planting during the whole growth period were used to evaluate the low nitrogen tolerance of five different genotypes of wheat based on the relevant morphological, yield and physiological indices. The results showed that under low nitrogen stress, the plant height of wheat decreased by 12% -29%, the dry weight of leaves decreased by 11% -57% and the ratio of root to shoot increased by 4% -52% The contents increased by 62.6% ~ 91.7%, while the nitrogen accumulation by leaves decreased by 47% ~ 71%. The maturity of wheat decreased by 21% -26%, the effective panicle number per plant decreased by 20% -41%, and the wheat yield decreased by 26% -69%. This indicated that the decrease of plant height, leaf dry weight and nitrogen accumulation could limit the wheat yield formation. It can be considered that there is a certain relationship between the low nitrogen tolerance of seedling and maturity of different genotypes of wheat. The genotypes of wheat differ in low nitrogen tolerance, and can be initially identified with low nitrogen tolerance at seedling stage. By comparing and identifying different traits of wheat seedling and maturity, we can dig out low nitrogen tolerant germplasm materials. Based on the characteristics of the tested materials, the possible mechanisms of low nitrogen tolerance were discussed according to the difference in their morphological and yield physiological indices.