【作者】 谢志坚；

【导师】 涂书新； 李进平；

【作者基本信息】 华中农业大学 ， 植物营养学， 2009， 硕士

【摘要】 环神农架地区是我国中部重要的烟叶生产基地,生产的“金神龙”烟叶具有“清香淡雅”的特点。然而,该地区土壤和气候两大主要生态条件随海拔高度变化而不同,导致烤烟产量和品质有所差异。探索在不同生态条件下,烤烟高产、稳产优质的农艺技术措施,对于彰显该地区烤烟的烟叶质量风格特色和提高产、质量都有重要意义。本研究以烤烟（Nicotiana tabacum L.）品种K326为试验材料,采用大田试验与稳定同位素(¹⁵N)示踪微区试验,研究烟苗不同移栽期、不同基肥施用时间和氮肥对2个不同植烟生态区[低海拔的赵家山（N 31°28′E 111°15′,海拔:903m）和高海拔的老湾（N 31°27′E 111°14′,海拔:1130m）]烤烟氮素吸收利用、生长发育、产量产值、烟碱含量以及烟碱氮素来源的影响,旨在明确环神农架烟区适宜的移栽期和基肥施用时间,为“金神农”优质烤烟生产提供科学理论指导。主要结果如下:1.不同移栽期试验结果表明,低海拔和高海拔两个植烟生态区,与不施用氮肥相比,施用氮肥显著促进烤烟各生育期地上部干物质累积,干物质累积量分别平均提高109%～238%和85%～175%;烤烟产量分别增加29.0%和19.2%,产值分别增加24.8%和25.7%。与5月5日移栽相比,推迟移栽期至5月15日～25日移栽,烤烟地上部干物质总累积量分别平均增加8.9%～17.8%和4.6%～11.7%;推迟移栽期对低海拔地区烤烟产量产值影响不明显,但显著提高高海拔地区烤烟产量产值10%～30%。另外,推迟移栽期,低海拔地区植株吸氮量增加25%～45%,而高海拔地区植株吸氮量平均下降6%～20%。低海拔赵家山和高海拔老湾试验点烤烟地上部氮肥利用率分别为30%和21%左右。推迟移栽期显著提高生育前期氮肥利用率,但在中后期无明显影响。与总氮积累趋势相反,推迟移栽期,烤烟各部位肥料氮占总氮的比例,低海拔地区下降10%～40%,而高海拔地区增加15%～50%。2.烤烟烟碱含量和烟碱氮占总氮的比例均随生育进程而逐渐增加。打顶之前,烟碱含量下部叶＞中部叶＞上部叶,打顶之后为上部叶＞中部叶＞下部叶。烤烟各部位烟叶烟碱氮中来源于肥料氮的比例随着生育进程和叶位上升均逐渐下降,尤其是打顶后烤烟上、中部叶中烟碱氮中肥料氮的比例急剧下降。由此可以推断,烤烟打顶后,土壤氮供应是影响烤烟上、中部叶,尤其是上部叶最终烟碱含量和累积量状况的主要因素。与不施氮相比,施用氮肥显著提高烟碱含量和烟碱氮占总氮比例,低海拔的赵家山地点分别平均提高44%～86%和3%～286%;高海拔的老湾地点分别为26%～33%和5%～127%。与5月5日移栽相比,5月15日～25日移栽,烟碱含量、烟碱氮占总氮比例以及烟碱氮中来源于肥料氮占总烟碱氮的比例,低海拔的赵家山地点分别平均降低5%～25%、13%～45%、13%～36%;而高海拔的老湾地点,分别平均增加10%～85%、5%～110%、21%～56%。3.不同基肥施用时间试验结果表明,低海拔和高海拔地区,施用氮肥烤烟地上部干物质积累分别平均增加0.78～3.05倍和2.10～2.72倍,烤烟产量和产值分别增加13%～40%和14%～35%。3个基肥施用时间对2个海拔试验点烤烟产量影响不显著,但是与移栽当天施用基肥相比,提前15d～30d施用基肥有利于提高烤烟的产值,高海拔试验点平均增加10%～30%。与提前0d或者15d相比,提前30d施用基肥还提高两个海拔地区烤烟对氮素的吸收累积量8%～26%。基肥施用时间对低海拔地区氮肥利用率的影响不显著,但是提前30d施用基肥显著提高高海拔地区烤烟生育中后期氮肥利用率3～6个百分点。在不同试验点,基肥施用时间对肥料氮占总氮的比例影响不同。提前施用基肥,低海拔地区,来自肥料氮的比例下降幅度为8%～32%,而高海拔地区增加25%～32%。结果说明,在光、温条件较差的高海拔地区,适当提前施用基肥（提前15d左右）,有利于提高肥料利用率,提高烤烟产量、产值。4.提前施用基肥（15d～30d）显著提高低海拔地区烤烟下部叶和高海拔地区各部位烟叶中烟碱含量,增幅为6%～19%。与提前0d或15d施用基肥相比,提前30d施用基肥,低海拔的赵家山地点,烤烟各部位烟叶中烟碱氮占总氮比例平均增加11%～34%:高海拔的老湾地点,中部叶和茎中烟碱氮占其对应总氮的比例分别显著增加14%～43%。低海拔赵家山地点,打顶之前,基肥施用时间对烤烟各部位烟叶烟碱氮中肥料氮占总烟碱氮比例的影响不显著,打顶之后,与提前0d相比,提前15d～30d施用基肥,中部叶肥料氮比例显著增加38%～43%。高海拔老湾地点,提前施用基肥显著增加烤烟生育前、中期上部叶烟碱氮中肥料氮占总烟碱氮的比例,但是基肥施用时间对成熟期各器官中肥料氮比例影响不显著。综上所述,施用氮肥是实现烤烟增产增收的重要农艺措施。在低海拔植烟生态区,推迟移栽期至5月15日～25日既有利于烤烟地上部对氮素的吸收利用、生长发育又能有效降低烟叶（尤其是中、上部叶）烟碱含量;而高海拔植烟生态区,适当提前移栽期（5月5日左右）既有利于烤烟地上部对氮素的吸收利用,又有利于降低烟叶（尤其是中、上部叶）烟碱含量。另外,两个海拔植烟生态区,提前15d～30d施用基肥有利于提高烤烟产值和促进烤烟对氮素的吸收利用。然而,基肥施用时间并不是越提前越好,建议提前15d左右施用基肥既有利于避免在移栽当天用工集中的矛盾又有利于降低烤烟烟叶烟碱含量。更多还原

【Abstract】 The area around Shenlongjia is a main flue-cured tobacco（FCT） production area, and the FCT leaves of"Jinshengnong" produced exhibit a character of"faint scent,sweet and refined".However,the soil and climate,the two main ecological conditions,change with the altitude hight,and lead to the difference of the production and the quality of tobacco.Investigating the agricultural techniques of high,stable and good quality of tobacco under different ecological conditions is of great importace for manifestating the characteristics of tobacco leaf and improving production and quality of tobacco in this district.Using FCT cultivar（Nicotiana tabacum L.K326）,a field experiment with ¹⁵N isotope tracing micro-plots was carried out to study the effects of different transplanting date,different basal N fertilization time and N fertilizer application on N uptake, utilization and distribution,the yields and market values,the growth and development,the nicotine concentrations and the origin of nicotine～N in different organs of plants FCT plants in two ecological tobacco production areas[Zhaojiashan（N 31°28′,E 111°15′, 903m above sea level） and Laowan（N 31°27′,E 111°14′,1130m above sea level）]of Xiangfan city,Hubei province.The object of this experiment is to work out the best transplanting date and basal N fertilization time,and to provide the scientific and theoretical guidance for production of good quality of tobacco leaves "Jinshengnong". The main results were as follows:1.The results from experiment of different transplanting date showed that in two ecological district,lower altitude and higher altitude,applying N fertilizer significantly increased dry matter accumulation in shoot of FCT plants at different growing stages by 109%～238%fold and 85%～175%respectively,increaced the yield by 29.0%and 19.2%, and the market values by 24.8%and 25.7%for the lower and higher sites,respectively. Compared to the transplanting date at 5^th May,the transplanting date at 15^th～25^th May,dry matter accumulation in the same organs of shoot of FCT plants at the same growing stages increaced gradually by 8.9%～17.8%and 4.6%～11.7%respectively;although there was no significant effect on the yield and market values of tobacco at the lower altitude site,but the yields and market values of tobacco were increased by 10%～30%at the higher altitude.When the transplanting date was put off to 15^th～25^th May,the total N accumulation by tobacco increased by 25%～45%at the lower altitude site,but decreased by 6%～20%at the higher altitued.The use efficiencies of nitrogen fertilizer were 30%（at the lower altitude site） and 21%（at the higher altitude）,which were improved significantly at earlier growing stage by delaying the transplanting time.On the contrary to total N accumulation,putting off the transplanting time decreased the use efficiency of N fertilizer by 10%～40%at the lower altitude site and increased by 15%～50%at the higher altitude. 2.The nicotine concentrations of tobacco leaves and the proportion of nicotine N to total N in different parts of FCT plants,increased gradually with the development of the plant and the increasing order of nicotine concentrations was lower leaf＞middle leaf＞upper leaf before the removal of apex,and was upper leaf＞middle leaf＞lower leaf affter the removal of apex.The proportion of nicotine N from fertilizer to total nicotine N decreased with the growing of FCT plants and the rising of leaf position.So,it was inferred that soil N application was the main factor that affected the nicotine concentrations and accumulations in middle and upper leaves（especially the upper ones） of FCT plants,after the removal of apex.Compared to without N fertilizer application, applying N fertilizer significantly increased nicotine concentrations and the proportion of nicotine N to total N by 44%～86%and 3%～286%at lower altitude,and by 26%～33% and 5%～127%at higher altitude,respectively.Compared to the transplanting date of 5^th May,postponing the transplanting date to 15^th～25^th May decreased the nicotine concentrations,the proportion of nicotine N to total N,and the proportion of nicotine N from fertilizer in organs of FCT plants,by 5%～25%,13%～45%,13%～36%at lower altitude,but increased by 10%～85%,5%～110%and 21%～56%at higher altitude, respectively.3.Results of the experiment with different basal N fertilization time showed that in two different FCT ecological districts,supplying N fertilizer significantly increased the dry matter accumulation by 0.78～3.05 fold and 2.10～2.72 fold,respectively;and the yields and market values of FCT plants by 13%～40%and 14%～35%for the experimental site of Zhaojiashan（lower altitude） and Laowan（higher altitude）,respectively.Basal fertilization time had no significant effects on the yields of FCT plants at both the two experimental sites,and compared to basal N fertilization time 0d before transplanting, basal N fertilization time 15d～30d before transplanting increased market values by 10%～30%at higher altitude.Early application of basal N fertilizer（30 d before transplanting） increased N uptake by 8%～26%as compared to that of applying basal N fertilizer at 0d or 15d before transplanting at the two ecological areas.There was no significant effects of basal N fertilizer application time on N fertilizer efficiency at lower altitude,but basal N fertilization time 30d before transplanting increased by 3%～6%at higher altitude.The proportion of fertilizer N to total N in FCT plants decreased by 8%～32%at lower altitude,but increased by 25%～32%at higher altitude when basal N fertilizer was supplied 30d before transplanting.These results indicated that properly earlier supplication of basal N fertilizer could improve the N fertilizer efficiency,and thus increase the yields and market values of FCT,especially at higher altitude areas with less sunshine and lower temperature.4.Early basal N fertilization time 15d～30d before transplanting significantly increased nicotine concentrations of lower leaves by 6%～19%at lower altitude and organs of shoot of FCT plants at higher altitude.Compared to the basal fertilization time 0d or 15d before transplanting,applying basal fertilizer 30d before transplanting increased the proportion of nicotine N to total N of organs of shoot of FCT plants at Zhaojiashan site（lower altitude） and that of middle leaves and stem at higher altitude by 11%～34%and 14%～43%,respectively.There was no significant effects of basal N fertilization time on the proportion of nicotine～N from fertilizer to total nicotine～N in organs of FCT plants before and after topping,in Zhaojiashan site and Laowan site respectively.But compared to basal N fertilization time 0d before transplanting,applying basal N fertilizer 15～30d before transplanting increased it that of middle leaves by 38%～43%significantly in Zhaojiashan site.Early basal fertilization time increased the proportion of nicotine～N from fertilizer to total nicotine～N of upper leaves significantly before topping in Laowan site.In summary,N fertilizer application was an important agricultural technique for improving yields and market values of FCT plants.Postponing the transplanting date to 15^th～25^th May was benefiting in promoting N uptake and utilization,growth and development and decreasing nicotine concentrations of FCT plants leaves（especially middle and upper leaves） effectively at lower altitude.Transplanting date at 5^th May or earlier was good for N uptake and utilization of shoot and decreasing nicotine concentrations of tobacco leaves.At two ecological districts,the basal N fertilization time 15d～30d before transplanting was helpful in improving the market values and the N uptake and utilization of FCT plants,which the basal N fertilization time 15d or so before transplanting could specially avoid the contradiction of workforce stress and decreasing nicotine concentrations.更多还原