钼对烤烟不同品种叶绿素荧光、抗氧化及氮代谢酶活性的影响

Effects of molybdenum on chlorophyll fluorescence,antioxidant activity and nitrogen metabolism in flue-cured tobacco of different varieties

利用营养液水培技术,以晚花K326和南江3号烟草品种为试验材料,于施钼和缺钼2个处理条件下水培30 d后,研究其对烤烟不同品种叶绿素荧光、抗氧化及氮代谢关键酶活性的影响。结果表明,和缺钼相比,晚花K326和南江3号品种的施钼烟株农艺性状明显增强,晚花K326和南江3号品种在根长、茎围和鲜重方面增幅分别为4.48%、26.52%、13.06%和7.13%、6.38%、5.52%。两个品种施钼烟叶的最大荧光产量Fm(maximal-fluorescence)和最大光化学量子产量Fv/Fm(optimal/maximal quanturn yield of PSⅡ)较缺钼都有所增加,晚花K326和南江3号增幅分别为10.33%、13.70%和13.52%、7.01%。晚花K326的过氧化氢酶CAT(Cat from micrococcus lysodeikticus)、过氧化物酶POD(Peroxidase)和超氧化物歧化酶SOD(Superoxide dismutase)活性较缺钼条件下显著增强,增幅为145.83%、90.72%和5.58%;南江3号的SOD活性较缺钼条件下增强,增幅5.76%。施钼烟草硝酸还原酶(Nitrate reductase,NR)活性较缺钼烟草有所增加,晚花K326和南江3号增幅分别为107.41%和16.00%,南江3号品种差异显著,晚花K326缺钼与南江3号缺钼差异显著。施钼烟草的谷氨酰胺合成酶(glutamine synthetase,GS)活性提高,晚花K326增幅较大;施钼晚花K326与南江3号差异显著,南江3号品种差异显著。施钼烟草亚硝酸盐含量均比缺钼烟草低,晚花K326和南江3号品种均表现为差异显著。综上,施钼不同程度促进了2个品种的生长发育,光合能力、抗氧化性和氮代谢增强,对晚花K326品种幼苗影响较为显著。

We studied the effects of molybdenum （Mo） on the growth, chlorophyll fluorescence, antioxidant activity and the activities of key enzymes involved in nitrogen metabolism in two flue-cured tobacco varieties, Wanhua K326 and Nanjiang 3 with or without Mo in culture solution for 30 days. Results showed that, compared with Mo deficiency, the agronomic traits of Wanhua K326 and Nanjiang 3 with Mo application were affected sig- nificantly by increasing the root length, stem girth and fresh weight of 4.48%, 26.52%, 13.06% and 7.13%, 6.38%, 5.52%, respectively. Fm （maximal -fluorescence output） and Fv/Fm （optimal/maximal quantum yield of PS II ） of the two varieties were also increased by 10.33%, 13.70% and 13.52%, 7.01%, respectively with Mo application. The activities of CAT （Cat fxom micrococcus lysodeikticus）, POD （peroxidase）, SOD （superoxide dismutase） in Wanhua K326 variety were obviously increased by 145.83%, 90.72%, and 5.58%, respectively with Mo application. The SOD activity in Nanjiang 3 increased by 5.76%, and the NR （nitrate reductase） activities in Wanhua K326 and Nanjiang 3 increased by 107.41% and 16.00%, respectively with Mo application as compared with Mo deficiency. The difference in NR activity between Wanhua K326 and Nanjiang 3 was significant under Mo defi- ciency condition. The glutamine synthetase （GS） activity increased with Mo application. Of which, Wanhua K326 varieties increased considerably. The GS activity in Nanjiang 3 and Wanhua K326 showed significant difference with Mo application, and the difference among Nanjiang 3 varieties were significant. The nitrite content in Mo application tobacco was lower than that in Mo deficiency, and the difference in nitrite content between Wanhua K326 and Nanjiang 3 was significant under Mo deficiency condition. In summary, Mo application could promote the growth of the two tobacco varieties and increase chlorophyll fluorescence, antioxidant and nitrogen metabolism. The effect of Mo application on Wanhua K326 tobacco variety was more significant than on Nanjiang 3.