大气CO_2含量增加对小麦籽粒营养品质的影响

Effects of increased atmospheric CO_2 concentration on nutrient quality of wheat grain

通过开顶式气室控制CO2 含量 ,对小麦籽粒品质实验测定 ,研究了大气CO2 增长对小麦籽粒蛋白质含量、蛋白质产量、氨基酸组分含量和主要营养元素含量的影响。结果表明 :在大气CO2 含量 (摩尔分数 )为 5 5 0和 75 0μmol/mol时 ,与正常大气CO2 水平相比 ,小麦籽粒蛋白质含量和氨基酸总量有降低趋势 ,但蛋氨酸、苯丙氨酸含量和蛋白质产量明显增加 ,蛋氨酸升幅为 8 2 %和 2 9 6 % ,苯丙氨酸升幅为 7 0 %和 17 9% ;小麦籽粒氨基酸评分值提高 3 1和 4 6。小麦籽粒中磷、铁、钾含量随大气CO2 含量增加而下降 ,分别下降 8 9%～ 11 8% ,7 5 %～10 8%和 2 5 %～ 7 7% ;而锌、硒、镁含量上升 ,分别提高 11 3%～ 34 4 % ,11 1%～ 4 4 4 %和 10 6 %～ 13 6 % ,大气CO2 增加对小麦籽粒各矿质营养元素含量的影响存在差异。

The protein contents, protein yields, relative contents of amino acids in protein and main nutrient elements contents of wheat grains were measured under ambient and increased CO 2 conditions, and effects of increased atmospheric CO 2 concentration on nutrient guality of wheat grains were analysed. The results showed that the protein contents and total amino acids contents of wheat grains decreased. The protein yields, methionine and phenylalanine contents increased by 13.1%-19.7%, 8.2%-29.6% and 7.0%-17.9% under elevated (550 and 750μmol/mol)CO 2, compared to the ambient air CO 2 concentration. At the same time, the amino acid scores of the grain protein increased by 3.1 and 4.6. It was also found that P, Fe and K contents of wheat grains decreased by 8.9%-11.8%, 7.5%-10.8% and 2.5%-7.7%. However, Zn, Se and Mg contents of wheat grains increased by 11.3%-34.4%, 11.12-44.4% and 10.6%-13.6% at two high CO 2 levels.