Dynamic Changes of Free Amino Acid,Protein and Its Components in Wheat with Different Quality Traits

Dynamic changes of amino acid,protein and its component of 4 wheat cultivars with different quality traits were investigated in the grains under the conditions of two N rates and two top dressing stages.The results indicated that free amino acid content had a high level in initial stages of grain development,and decreased gradually with the progress of grain development until maturity;protein content showed the same high-low-high trend,and cultivars with higher protein content had a higher accumulation level of free amino acid and protein.The content of each protein component showed the similar changing trend during grain developing period,but their contents were different at different stages.Albumin had a higher content at early developing stage,decreased slowly at late filling stage.Globulin content was relatively lower during whole grain developing period,slowly decreased with the development of grain,and increased slightly in the late stage of grain filling.Gliadin had less content at early developing period,and accumulated quickly after 14th day of anthesis.Glutenin had accumulated after 7th day of anthesis.Gliadin and glutenin contents went up gradually.The cultivar with higher protein had a higher Gliadin and glutenin accumulation level,and did the percentage of gliadin and glutenin on total protein in the same case,while the cultivars with lower protein content were on the reverse.