施用纳米碳对烤烟氮素吸收和利用的影响

Abstract

为明确纳米碳在提高烤烟氮素吸收利用方面的效果，在盆栽条件下，研究了纳米碳不同用量对烤烟根系生长发育、干物质积累和氮素吸收利用的影响。结果表明，在常规肥料中添加纳米碳能够促进烤烟根系生长发育，明显提高烟株根系活力和单株根系生物量，增加植株干物质积累量。施用纳米碳增加了烤烟植株成熟期各器官氮素含量和积累量，而未明显影响氮素在植株不同器官的分配。施用纳米碳不仅增加了植株对肥料氮的吸收量，还增加了对土壤氮的吸收量，这与其促进烤烟根系生长发育、提高根系吸收能力有密切关系。纳米碳无论做基肥还是做追肥，均显著提高了氮肥利用率，提高幅度分别达到14.44%和9.62%，有效降低了氮素土壤残留和损失。;With the improvement of the agricultural technology, especially the application of chemical fertilizers, the crop yields have greatly increased in the past few decades. Nitrogen application is one of the most important measures to increase yield and improve quality in tobacco production. Although nitrogen supply drives productivity, excessive nitrogen fertilizers and irrational application have become the serious problems in many fields. The residual nitrogen in the soil caused not only the decrease of nitrogen use efficiency, but also the increasing risk of environmental pollution. Thus, improving fertilizer nitrogen use efficiency and reducing fertilizer losses are significant to the agricultural development and environmental protection.<br>Nanomaterials have some particular properties such as surface effect, volume effect, quantum size effect, and so on, which macro materials do not have. Nanotechnology has become one of the hot topics in the scientific research field because of its wide applications. Many studies found that nanomaterial can enhance crop seed germination and promote plant growth. And chemical fertilizer utilization rate can be increased by nanomaterial application in soil. Tobacco is an important economic crop in our country, and excessive fertilization occurs occasionally in tobacco production. A recent study has shown that carbon nanotubes induce growth enhancement of tobacco cells. However, to date, only few reports exist on the effects of nanomaterial on tobacco growth and nutrient absorption. So this study was conducted to determine the effects of nanocarbon on nitrogen absorption, assimilation and use efficiency of tobacco plant using ¹⁵N tracer technique, to provide theory basis for nanocarbon research and application. A pot culture experiment was carried out with tobacco cultivar Zhongyan100 in the greenhouse of Zhengzhou Tobacco Research Institute. Four treatments (T1, T2, T3, T4) were set up and each treatment had 15 pots. Eight pots of T1 and T3 treatment were used for ¹⁵N tracer experiment. Plant organ and soil samples were taken for analysis at the resettling growth stage, vigorous growth stage and maturity stage. <br>The results showed that nanocarbon application promoted root growth, increased root biomass and root vigor, and increased dry matter accumulation of tobacco plant. At maturity stage, compared with T1, the dry matter accumulation of root, stem and leaf increased 6.73%, 19.17%, 7.92% (T3) and 9.12%, 12.44%, 3.89% (T4), respectively. Nanocarbon application increased nitrogen content and nitrogen accumulation amount, without effect on nitrogen distribution of different organs of flue-cured tobacco. At vigorous growth stage and maturity stage, the plant nitrogen uptake, 25.29%-34.62% of which derived from fertilizer and 65.38%-74.01% from soil. Nanocarbon application increased nitrogen absorption amount both from soil and fertilizer, which attributed to strong root absorption ability. The total nitrogen uptake increased by 14.11% and 15.63% at vigorous growth stage and maturity stage by the nanocarbon application. Nanocarbon application increased nitrogen utilization rate by 14.44% (base fertilizer) and 9.62%(top dressing), respectively. Meanwhile, the residual ratio and loss ratio decreased significantly by the nanocarbon application, which had great benefit of decreasing nitrogen loss. Therefore, nanocarbon is suitable for making new fertilizer and using in tobacco production.