水氮运筹对紫色土旱地烤烟碳代谢、生长及品质的影响

摘要

In order to discuss the appropriate mode for coupling water and N fertilizers,the experiment was car-ried out with the split plot design to study the effects of irrigation and nitrogen management on carbon metabolism, growth and quality of tobacco in dry-land purple soil. Results showed that irrigation and application of nitrogen fer-tilizer could improve the SPAD,chlorophyll contents,photosynthesis and photosynthetic products for middle leaves in the long-term period. Enhancing the ratio of top dressing could promote the carbon metabolism under different water conditions. Leaves dry biomass,N accumulation amount increased with N fertilization and the ratio of top dressing increasing in the long-term and mature period,and which were higher under the irrigation condition comparing with natural rainfall. Chemistry analysis of cured tobacco leaves indicated that irrigation and the ratio of top dressing in-creasing could improve reducing sugar content,and decreased total nitrogen and nicotine contents. To comprehen-sively concluded our results,it could be regarded that the rational mode of irrigation and nitrogen management could promote tobacco growth,carbon metabolism and enhance the effect of coupling water and N fertilizers further.%为探讨紫色土旱地烤烟适宜水氮耦合模式，采用裂区试验设计研究了水氮运筹对赣南紫色土旱地烤烟碳代谢、生长及品质的影响。结果表明，灌水和施用氮肥能够提高旺长期中部叶的 SPAD值、叶绿素含量、光合作用及可溶性糖和淀粉的含量。不同水分条件下，增加氮肥追肥比例均能促进烤烟光合作用。旺长期和成熟期叶片干物质量、氮累积量随施氮量和追肥比例的增加而增加，且灌水处理高于自然降雨处理；灌水和增加氮肥追肥比例能够提高中部叶还原糖含量，降低总氮和烟碱含量。综上所述，合理的水氮运筹能够促进烟株的生长和代谢，进一步加大烤烟水氮耦合效应。