顶端调控措施对烤烟叶片多酚氧化酶活性和酚类化合物含量的影响

目的]为改进烟叶品质提供参考依据。方法]以云烟87为供试品种,设置6个处理:T1不打顶;T2打顶;T3打顶+追施硫酸钾肥;T4打顶+涂抹生长素1次;T5打顶+追施硫酸钾肥+涂抹生长素1次;T6打顶+追施硫酸钾肥+涂抹生长素2次,分析不同顶端调控措施对烤烟叶片多酚氧化酶(PPO)活性和酚类化合物含量的影响。结果]随着生育时期的延长,PPO活性呈现先升高后下降的趋势,不打顶处理的PPO活性峰值出现较早,打顶处理的PPO活性峰值明显延迟,在成熟期,各处理的PPO活性高低顺序为:T6>T5>T3>T4>T2>T1。各处理的酚类化合物含量则随生育时期的延长逐渐升高,在成熟期的高低顺序为:T3>T2>T5>T4>T6>T1。打顶后在茎断面涂抹生长素并辅施硫酸钾肥,能使烤烟叶片的PPO活性升高,酚类化合物含量适当降低。在打顶后20d之前,酚类化合物含量与PPO活性的相关系数为0.826**,打顶20d后,二者的相关系数为-0.268。结论]打顶后在茎断面涂抹生长素,并辅施硫酸钾肥,可增强PPO活性,提高大田烟叶质量。

Effects of Agronomic Measures after Topping on Polyphenol Oxidase Activity and Phenolics Content in Flue-cured Tobacco Leaves

Objective] The aim was to provide reference base for improving the quality of tobacco leaf.Method] With Yunyan 87 as tested variety,6 treatments were set up as T1(no topping),T2(topping),T3(topping dressing K2SO4 fertilizer),T4(topping smearing IAA once),T5(topping dressing K2SO4 fertilizer smearing IAA once) and T6(topping dressing K2SO4 fertilizer smearing IAA twice) to analyze the effects of different Agronomic measures after topping on polyphenol oxidase(PPO) activity and phenolic compound content in flue-cured tobacco leaves.Result] PPO activity showed the trend of first increasing and then decreasing with the prolonging of growth period.The peak value of PPO activity occurred earlier in the treatment without topping and had an obvious delay in the treatment with topping.During the mature period,PPO activity order of treatments was T6>T5>T3>T4>T2>T1.The phenolic compound contents in the treatments increased gradually with the prolonging of growth period and the order in the mature period was T3>T2>T5>T4>T6>T1.Smearing IAA on the cross-section of stem and supplementing K2SO4 fertilizer after topping could increase PPO activity and properly decrease phenolic compound content in flue-cured tobacco leaves.Before the 20th day since topping,the correlation coefficient between phenolic compound content and PPO activity was 0.826 and after the 20th day their correlation coefficient became-0.268.Conclusion] Smearing IAA on the cross-section of stem and supplementing K2SO4 fertilizer after topping could enhance PPO activity and increase the quality of tobacco leaves in field.