水肥一体化条件下阶段性动态水肥供应对烤烟生理特性的影响

Effects of Phased Dynamic Water and Fertilizer Supply on Physiological Characteristics of Flue-cured Tobacco under Integration of Water and Fertilizer

为分析水肥一体化条件下动态水肥供给对烤烟生长应用效果,试验设置了常规水肥管理(CK)、常规施肥管理+动态水分供给(T_(1))、减肥条件下水肥一体化动态水肥管理(T_(2)),通过大田试验,测定了烟株不同生长时期的叶绿素含量、碳氮代谢关键酶活性及烤烟的主要化学成分。结果表明:(1)烟株生长前期,T_(1)和T_(2)的叶绿素含量和净光合速率均高于CK,随着烟叶成熟,T_(1)的叶绿素含量和净光合速率降幅最大,其次为T_(2);(2)T_(1)和T_(2)均能显著提高烟叶的淀粉酶活性和生长前期的硝酸还原酶活性,其中T_(1)和T_(2)的硝酸还原酶活性峰值较CK提前,随着烟叶成熟,两者的酶活性迅速下降;(3)在施用肥料总量减少情况下,T_(2)主要化学成分含量均低于T_(1),其中烟碱含量差异显著。由此可知,动态水肥供给能实现水肥同步,依据烟株水肥吸收规律,通过调控不同生长期烟株营养供给,显著提高了烟株生长前期的叶绿素含量、光合速率以及碳氮代谢关键酶活性,随着后期养分的调亏,烟叶落黄特征和碳氮代谢协调程度均优于常规水肥管理,有利于烟叶品质的提高。

To clarify the application effect of dynamic water and fertilizer supply on the growth of flue-cured tobacco under the integration of water and fertilizer,we set up conventional water and fertilizer management(CK),conventional fertilization management+dynamic water supply(T_(1)),integrated water and fertilizer dynamic water and fertilizer management under the condition of weight loss(T_(2))in the experiment.The field experiments were conducted to detect the chlorophyll content,carbon and nitrogen content,metabolism key enzyme activity and main chemical composition content of tobacco plants in different growth periods.The results showed that:(1)In the early stage of tobacco plant growth,the chlorophyll content and net photosynthetic rate of T_(1) and T_(2) were both higher than those of CK.With the maturity of tobacco leaves,the chlorophyll content and net photosynthetic rate of T_(1) decreased the most,followed by T_(2).(2)T_(1) and T_(2) Both can significantly increase the amylase activity of tobacco leaves and the activity of nitrate reductase in the early growth period.The peaks of T_(1) and T_(2) nitrate reductase activity were earlier than those of CK.With the maturity of tobacco leaves,the enzyme activities of the two decreased rapidly.(3)When the total amount of fertilizer applied decreased,the content of main chemical components of T_(2) was lower than that of T_(1),and the content of nicotine was significantly different.Dynamic water and fertilizer supply could achieve synchronization of water and fertilizer.According to the law of tobacco plant water and fertilizer absorption,by regulating the nutrient supply of tobacco plants in different growth periods,the chlorophyll content,photosynthetic rate and key enzyme activities of carbon and nitrogen metabolism in the early growth period of tobacco plants were significantly increased.With the regulation of nutrient deficit in the later period,yellowing characteristics of tobacco leaves and the coordination degree of carbon and nitrogen metabolism were better than conventional water and fertilizer management,which was beneficial to the improvement of tobacco leaf quality.