施氮量对烤烟成熟期叶片生理特性的影响

Effects of Nitrogen Application Rate on Physiological Characteristics of Flue-Cured Tobacco Leaves at the Maturing Stage

为明确不同施氮量在烟叶成熟时期对上、中部烟叶生理特性的影响,2012年在河南省许昌市以烤烟品种"中烟100"为研究对象,打顶后每隔5 d取样,测定了不同成熟时期、不同部位的鲜烟叶在氮肥梯度下的叶绿素含量、硝酸还原酶活性、可溶性蛋白质及游离氨基酸含量.结果表明,不同施氮量对上、中部叶成熟过程的氮代谢活动影响较大.在上部烟叶逐渐成熟过程中,不同的施氮量对烟叶中的叶绿素、可溶性蛋白质含量影响不显著,对硝酸还原酶活性影响显著,对游离氨基酸含量影响极显著;在中部烟叶逐渐成熟过程中,不同施氮量对可溶性蛋白质含量影响不显著,对硝酸还原酶活性影响显著,对叶绿素、游离氨基酸含量影响均极显著.可见,只有适量施用氮肥,才能生产出优质烟叶,本研究中以施氮量45 kg/hm2最佳.

Effects of nitrogen application rate on physiological characteristics of flue-cured tobacco leaves at the maturing stage were studied by surveying chlorophyll content , nitrate reductase（NR） activity, sol-uble protein content and free amino acid content of fresh leaves of Zhongyan 100 , a variety planted in Xuchang city of Henan Province , from different positions and in different periods every 5 days, form April to September , 2012 .The results showed that during the gradually mature process of tobacco , effects of nitrogen application rate on soluble protein content and chlorophyll content of the upper tobacco leaves were not significant , but it was significant on NR activity and free amino acids content .The effect of ni-trogen application rate on soluble protein content of the middle tobacco leaves were not significant , but it was significant on NR activity , chlorophyll content and free amino acids content .Only appropriate a-mount of nitrogen application could produce high quality tobacco leaves .The treatment of 45 kg/hm2 pure nitrogen was the best .