打顶后施用生长素和钾肥对烤烟根系性状及品质的影响

Effects of applying auxin and potassium fertilizer on root characters and leaf quality of flue-cured tobacco after topping

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)共6种调控措施对烤烟根系性状、ATP酶活性、烟碱和钾含量、烤后烟叶中性挥发性致香物质含量及经济性状的影响。结果表明:与T2相比,打顶后30d根系干重的增幅依次为:T6(52.76%)>T5(22.33%)>T3(10.11%)>T4(8.55%),T3、T5、T6的根系活力明显提高,T6的ATP酶活性远高于其他处理。涂抹生长素和追施K2SO4肥对根系烟碱的合成具有一定的抑制作用;与T2相比,在打顶后30d烟碱的降幅依次为:T4(35.09%)>T6(31.58%)>T5(24.56%)>T3(15.79%)。随生育进程延长,根系吸收钾的能力逐渐降低;与T1相比,在打顶后30d各处理烤烟根系钾含量降幅依次为:T2(63.41%)>T4(60.98%)>T3(56.10%)>T5(50.00%)>T6(47.56%)。T6中性致香物质总量最高,各项经济指标值较优。打顶当天在茎断面涂抹生长素,并于根部灌施K2SO4肥,促进了烤烟根系生长和品质形成。

Effects of six types of agronomic measures including no topping （T1）, topping （T2）, topping ＋ K2SO4（T3） , topping ＋ applying IAA 1 time （T4）, topping ＋ K2SO4 ＋ applying IAA 1 time （T5）, and topping ＋ K2SO4 ＋ applying IAA 2 times （T6） on root properties, nicotine and potassium content in root, volatile aroma matter content in leaf and leaf economic characters of flue-cured tobacco were studied. Compared with T2, the order for dry weight of roots at 30 days after topping was T6 （52.76%） 〉 T5 （22.33%） 〉 T3 （10.11%） 〉 T4 （8.55%）. Root activity of treatment T3, T5 and T6 was improved obviously, and T6 had much higher ATP activity than the other treatments. Nicotine synthesized in roots could be controlled when tobacco was applied with IAA and K2SO4 fertilizer. Compared with T2, the order for nicotine content at 30 days after topping was T4 （35.09%） 〉 T6 （31.58%） 〉 T5 （24.56%） 〉 T3 （15.79%）. The ability of absorbing potassium weakened gradually with the days increasing after topping. Compared with T1, the order for content of potassium in roots was T2 （63.41%） 〉 T4 （60.98%） 〉 T3 （56.10%） 〉 T5 （50.00%） 〉 T6 （47.56%） at 30 days after topping. T6 had the highest total content of volatile aroma matter after curing and best economic characters. The growth of roots and the quality of flue-cured tobacco leaves could be promoted by applying auxin and potassium fertilizer at the topping day.