去叶和去小穗对小麦籽粒微量元素和蛋白质含量的影响

Effect of leaf and spikelet removal on grain micronutrient and protein concentration in wheat

为了解小麦不同部位叶片对籽粒微量元素(Zn、Fe、Mn和Cu)和蛋白质含量的影响以及不同品种微量元素和蛋白质含量的源库限制程度,以8个冬小麦品种为材料,通过开花后去倒一叶、倒二叶、倒三叶和去50%小穗处理,分析成熟期籽粒中Zn、Mn、Fe、Cu和蛋白质含量与籽粒重的变化及其相互关系。结果表明,不同部位叶片的去除均降低了籽粒重和蛋白质含量,也降低了籽粒中Zn、Mn、Fe和Cu含量;几个品种平均来看,去倒一叶处理籽粒重下降幅度最大,为14.43%,去倒二叶处理籽粒微量元素含量下降幅度最大,Zn、Mn、Fe和Cu含量分别下降11.31%、15.27%、10.29%和8.32%,去倒三叶处理籽粒蛋白质含量下降幅度最大,为11.63%,各品种对去叶的反应有差异。去小穗减少库,剩余籽粒Zn、Mn、Fe、Cu和蛋白质含量分别提高26.02%、25.01%、8.93%、8.99%和3.51%,剩余籽粒粒重提高10.41%,说明籽粒Zn、Mn、Fe、Cu和蛋白质含量主要受各元素供源限制,且受源限制程度因品种而异。籽粒中4种微量元素含量之间及其与蛋白质含量之间具有一定的正相关性,说明籽粒微量元素含量与蛋白质含量存在同步提高的可能性,蛋白质含量可作为衡量Fe、Zn等元素含量高低的参考。

In this study,8 winter wheat cultivars were selected to study the effect of ）eaf at different position on grain micronutrient（Zn, Fe, Mn and Cu） and protein concentration as well as the source and sink limitation for grain micronutrient and protein accumulation by removing the leaf（the flag leaf, the 2;a leaf and the 3rd leaf） and spikelet（50% of spikelet removal） after anthesis. The results showed that,in the defoliation treatment,accompanied by the reductions of grain weight and protein concentration in grains, the concentrations and contents of Fe, Zn, Mn, and Cu in grains were reduced,and there was a significant difference in cultivar response to defoliation. It indicated that the most decrease in grain weight was caused by the treatment of the flag leaf removal （decreased by 14.43%）;the most decrease in micronutrient concentration was caused by the 2nd leaf removal treatment（decreased by 11.31%, 15.27%, 10.29% and 8.32% respectively for Zn,Mn, Fe and Cu） ;the most decrease in protein concentration was caused by the 3re leaf removal treatment（decreased by 11.63% ）. In the treatment of 50% of spikelet removal,the single grain weight and the concentrations ofZn,Mn, Fe,Cu and protein increased by 10.4%,26.02%,25.01%,8.93%,8.99% and 3.51% respectively. The concentrations of Fe, Zn, Mn, Cu and protein in grains were restricted by source supplies of the corresponding element,but the effects of the source supply were different across the elements and wheat genotypes. Correlation analysis showed that all coefficients of correlation were significantly positive among the concentrations or contents of Fe,Zn,Mn,Cu and protein in grains. This implies that the 4 micronutrients in grains are possibly increased with grain protein concentration simultaneously, and the protein concentration in grains may be an index to measure the grain Fe,Zn,Mn and Cu concentrations in wheat.