烤烟不同生育时期分根区交替灌溉的节水调质效应

为寻找烟田节水调质灌溉方式的理论依据，本文通过盆栽试验研究了两种施肥条件下，不同生育时期分根区交替灌溉（APRI）对烤烟生理特性、水分利用以及主要品质指标的影响。结果表明，APRI能有效地调节气孔开度，降低气孔导度和蒸腾速率，减少其奢侈蒸腾耗水，达到节约灌水量和提高水分利用效率（WUE）的目的。与常规灌溉（CI）相比，不同生育期APRI处理低肥时平均节水10.6%，高肥时平均节水6.1%，低肥时烟叶WUE平均提高2.3%。APRI还可以明显提高烟叶K、还原糖和粗蛋白含量，改善烟叶的内在品质。与CI相比，APRI处理烟叶K和粗蛋白含量，低肥时平均提高19.9%和7.1%；高肥时平均提高29.5%和15.1%，低肥伸根期APRI还原糖含量提高17.6%，烟碱含量降低25.7%。本研究结果表明，低肥时在烤烟伸根期进行分根区交替灌溉是烟叶生产中一种较好的节水调质的烟田灌溉方式。

Effects of alternate partial root-zone irrigation on water saving and quality regulating of flue-cured tobacco at different growth stages

In order to investigate the theoretical foundation of irrigation method for tobacco production with water saving and quality regulating, the effect of alternate partial root-zone irrigation (APRI) on leaf physiological characteristics, water use and main quality indices of flue-cured tobacco during different growth stages under two fertilization levels was studied in a pot experiment. Results showed that APRI could regulate stomatal opening, reduce stomatal conductance, transpiration rate and water consumption of flue-cured tobacco, thus APRI could reduce irrigation water and increase water use efficiency (WUE). Compared with conventional irrigation (CI), APRI treatment during different growth stages of tobacco saved irrigation water by 10.6% under lower fertilization and 7.1% under higher fertilization, respectively. APRI also increased tobacco WUE by 2.3% under lower fertilization. APRI significantly increased K, soluble sugar and protein contents and then improved the quality of flue-cured tobacco. Compared with CI, APRI increased K and protein contents by 19.9% and 7.1% under lower fertilization, and by 29.5% and 15.1% under higher fertilization. And APRI treatment during in the root extending stage increased soluble sugar content by 17.6% and reduced the nicotine content by 25.7% under lower fertilization, respectively. Thus APRI at the root extending stage was an efficient irrigation method for tobacco production with water saving and quality regulating under lower fertilization in this study.