氮素对羽叶决明缩合单宁及相关酶活性的影响

缩合单宁对牧草品质的影响极大,适量的缩合单宁含量对于提高牧草的利用率和营养品质非常重要。研究以豆科牧草羽叶决明Cassia nictitoms为材料,分析了氮素梯度处理后茎和叶中缩合单宁的含量及其生物合成酶二氢黄酮醇还原酶(DFR)活性的变化特征。结果表明,羽叶决明叶片的缩合单宁含量高于茎,随氮素的增加,叶片中缩合单宁含量从14.78%下降到1.14%;茎中从4.62%开始降低,达到0.98%后趋于稳定;DFR活性表现出与缩合单宁相似的变化规律,二者在叶和茎中都呈显著(P0.01)的二次曲线关系。植株粗蛋白含量测定发现,随氮素的增加粗蛋白含量无显著增加(P0.05)。因此,适当增加氮素的使用量可以达到减少缩合单宁含量,从而提高羽叶决明的利用率和营养品质。

Effects of nitrogen level on condensed tannins and activity of related enzyme in Chamaecrasta nictitans

Condensed tannins(CT) affect the quality of the forage greatly.Proper amount of CT could improve the utilization rate and the nutritional quality for the forage.Content of the CT was examined with vanillic aldehyde,and the Dihydroflavonol 4-Reductase(DFR) activity was determined with real-time monitor method after fertilizing different level of nitrogen on legume forage,Chamaecrasta nictitans.The condensed tannins decreased as nitrogen level increased,from 14.78% to 1.14% in leaves,from 4.62% to 0.98% in st...