土壤水分对不同筋力型小麦花后旗叶氮素同化酶活性和籽粒蛋白质含量的影响

Effect of Soil Moisture Levels on Activity of Nitrogen Assimilation Enzymes in Post-anthesis Flag Leaves and Grain Protein Content of Different Gluten Content of Wheat

为给不同类型小麦栽培中土壤水分管理提供依据,在盆栽条件下,研究了土壤水分对不同筋力型小麦花后旗叶氮素同化酶活性和籽粒蛋白质含量的影响。结果表明,强筋小麦豫麦34花后旗叶中硝酸还原酶(NR)活性表现为:土壤含水量为田间持水量(FC)60%处理的活性最强,其次为40%FC处理,80%FC处理最低,谷氨酰胺合成酶(GS)、谷氨酸合成酶(GOGAT)活性大小关系均为:80%FC处理>60%FC处理>40%FC处理。中筋小麦豫麦49旗叶NR、GS总体上以60%FC处理最高。弱筋小麦豫麦50旗叶NR活性基本表现为60%FC处理>40%FC处理>80%FC处理,GS活性以80%FC处理为最高。土壤水分适度胁迫可提高籽粒蛋白质含量,豫麦34以60%FC处理籽粒蛋白质含量最高,豫麦49、豫麦50则以40%FC处理籽粒蛋白质含量最高。不同土壤水分处理下小麦籽粒蛋白质含量与旗叶NR、GS均呈正相关,与GOGAT均呈不显著负相关。

Effects of soil water on activity of nitrogen assimilation enzymes in post-anthesis flag leaves and grain protein content of different gluten content of wheat were studied in pot experiments. The results showed that nitrate reductase（NR） activity in post-anthesis flag leaves of Yumai 34, a strong gluten cultivar, changed as follows, it was the strongest when soil water content was 60% field capacity （FC）, it was the lowest when the water content was 80%FC, and it was in between when the water content was 40% FC. The order of GS （glutamine synthetase ） activity and GOGATE （glutamate synthase） activity were both as 80%FC〉60%FC〉40%FC. The maximum activity of NR and GS activity in flag leaves of Yumai 49, a medium gluten cultivar, appeared when water content was 60%FC. The order of NR activity in flag leaves of Yumai 50, a weak gluten was generally as 60%FC〉40%FC〉80%FC. The maximum activity of GS in flag leaves of Yumai 50, a weak gluten cultivar, appeared when water content was 80%FC. Soil water stress improved grain protein content. The grain protein content of Yumai 34 was the highest when water content was 60%FC, and for Yumai 49 and Yumai 50 the highst protein content appeared when water content was 40%FC. Protein content was positively correlated to NR and GS activities in the flag leaves,but was not significantly and negatively correlated to GOGATE activity at different water levels.