施氮量及基追比对烤烟氮代谢产物及关键酶的影响

Effects of Nitrogen Application Rate and Fertilizer Ratio on Nitrogen Metabolites and Key Enzymes of Flue-cured Tobacco

为探究不同施氮量及基追比对烤烟氮代谢产物及关键酶活性的影响,本试验以‘云烟87’为试验材料,采用大田双因素随机区组设计。结果表明:适宜施氮量及基追比对烤烟氮代谢及关键酶活性均有促进作用,过高的氮素则产生不同程度抑制。随施氮量增加,烤后烟叶总氮和烟碱含量均呈上升趋势,但过高氮素会影响上部烟叶氮代谢产物;不同施氮量下均在基追比5:5时氮代谢较协调,其中又以常规施氮下5:5时表现最佳。过高氮素在旺长期以前对NR和Ni R活性均产生不同程度抑制,且均在低氮水平下基追比为6:4最佳;现蕾以后抑制减弱,NR和Ni R在常规施氮下基追比分别为6:4和5:5表现最优。GS和GDH分别在常规施氮和低氮处理下活性最好,旺长期前GS活性在基追比为6:4总体表现较好,旺长期以后则以5:5最佳;GDH在低氮处理下各生育期最佳基追比均为6:4。综上,在黔西南安龙烟区,烤烟在常规施氮量下基追比为5:5时有利于促进代谢物的产生和关键酶活性的提升。

In order to explore the effects of different nitrogen application rates and fertilizer ratios on the nitrogen metabolites and key enzyme activities of flue-cured tobacco,this experiment took 'Yunyan87' as the experimental material,and adopted a field two-factor random block design.The results showed that the appropriate amount of nitrogen application and fertilizer ratio could promote the nitrogen metabolism and key enzyme activities of fluecured tobacco,while excessive nitrogen would inhibit it to varying degrees.With the increase of nitrogen application rate,the content of total nitrogen and nicotine in the cured tobacco leaves showed an upward trend,but too high nitrogen content would affect the nitrogen metabolites in the upper tobacco leaves;under different nitrogen application rates,the nitrogen metabolism was lower when the base-to-topdressing ratio was 5:5.coordination,and the performance was best when the conventional nitrogen fertilization was 5:5.Excessively high nitrogen inhibited the activities of NR and Ni R to varying degrees before the blooming period,and the fertilizer ratio of 6:4 was the best at low nitrogen levels;the inhibition weakened after budding,and the activities of NR and NiR could Fertilizer ratios of 6:4 and 5:5 were the best.GS and GDH had the best activity under conventional nitrogen fertilization and low-nitrogen treatment respectively.The activity of GS was better when the fertilizer ratio was 6:4 before the prosperous period,and 5:5 was the best after the prosperous period;The best ratio of fertilizer in each growth period under treatment was 6:4.In conclusion,in Anlong Tobacco Area in Southwest Guizhou,when the fertilizer ratio of flue-cured tobacco is 5:5 under the conventional nitrogen application rate,it is beneficial to promote the production of metabolites and the improvement of key enzyme activities.