打顶后烤烟叶片酶活性、钾及烟碱含量的调控技术研究

研究了不打顶(T1)、打顶(T2)、打顶+追施K2SO4(T3)、打顶+涂抹生长素1次(T4)、打顶+追施K2SO4+涂抹生长素1次(T5)、打顶+追施K2SO4+涂抹生长素2次(T6)6种调控措施对烤烟叶片硝酸还原酶(NR)活性、过氧化物酶(POD)活性、钾含量及烟碱含量的影响。结果表明,T6在成熟期的NR与POD活性最强,T1最弱。在打顶后随生育时期的延长,各处理烟叶中钾含量逐渐下降,以T1和T6下降幅度最小,T2下降幅度最大,而T3,T4和T5下降幅度居中,成熟期钾含量(%)依次为:T1(3.59)T6(2.77)T5(2.47)T3(2.11)T4(2.10)T2(1.88)。与此相反,各处理烟叶在打顶后烟碱含量逐渐上升,成熟期烟碱含量(%)依次为:T2(3.48)T3(3.03)T4(2.92)T5(2.70)T6(2.45)T1(1.14)。大田期叶片钾含量与烟碱含量呈极显著的负相关关系(-0.938**),与NR及POD活性均呈极显著的正相关关系,相关系数分别为0.838**和0.859**。烤后烟叶以T6的化学成分最为协调,其烟碱含量适中,淀粉含量较低,钾和总糖含量较高。打顶后在茎断面涂抹生长素(IAA),同时根部追施K2SO4,具有较好的提钾控碱的效果。

Agronomic regulation on NR and POD activities, K and nicotine contents after topping in flue-cured tobacco leaf

The effect of different agronomic measures namely No topping(T1),Topping(T2),Topping K_2SO_4(T3),Topping applying IAA 1 time(T4),Topping K_2SO_4 applying IAA 1 time(T5),and Topping K_2SO_4 applying IAA 2 times(T6) on NR and POD activities,potassium and nicotine content in flue-cured tobacco leaf was studied in this paper.The results showed that T6 had the highest NR and POD activities,and T1 had the lowest NR and POD activities in mature leaf.With the time after topping,K content for different treatments decreased stepwise with lowest magnitude for TI and T6 and highest magnitude for T2.The order of potassium content(%) at mature leaf for different treatments was T1(3.59)>T6(2.77)>T5(2.47)> T3(2.11)> T4(2.10)>T2(1.88).On the contrary,content of nicotine for different treatments increased stepwise with time after topping,and the order of nicotine content(%)at mature period was T2(3.53)> T3(3.03) > T4(2.92) > T5(2.70) > T6(2.45) > T1(1.18).At field period,potassium content had highly significant negative correlation with nicotine content(r=-0.938,P<0.01),and highly significant positive correlation NR and POD activity with correlation coefficients of 0.838and 0.859 respectively(P<0.01).After flue-curing,the chemical components of cured leaf for T6 were well coordinated with a suitable content of nicotine, lower content of starch,and highest content of potassium and total sugar.Applying both IAA and K_2SO_4 in the topping day could increase potassium and decrease nicotine in flue-cured tobacco leaf.