【作者】 张雪芹；

【导师】 彭克勤；

【作者基本信息】 湖南农业大学 ， 植物学， 2008， 博士

【摘要】 烤烟是我国重要的经济作物之一,烟草业是我国烟区农民脱贫致富的支柱产业,也是我国财政收入的主要来源。我国是一个烟草生产和消费大国,但却不是一个烟草强国。中国的原烟产量和卷烟产量各占世界的30%和32%,而出口量分别占世界的3.5%和1.8%。烟叶质量不高是我国烟叶出口比例较低、效益较差的主要限制原因,其中烟叶含钾量低是制约烟叶质量提高的主要原因。烟草施肥的目的在于提高烟叶的产量和品质,为卷烟工业提供优质原料。在目前主要的烟草栽培体系中,施肥不仅决定烟叶产量、产值,而且影响烟叶的均价、上等烟叶的比例。因此,在一定的环境和品种条件下,施肥是调控烟叶产量和质量的核心技术。目前,科学经济施肥,提高烟叶的含钾量,实现烟叶优质适产,已成为烟叶生产的关键。本研究通过水溶出率法和土壤溶出率法研究包膜钾肥钾素养分释放特性及外界因素对养分释放的影响并筛选出较合适的缓释钾肥。并通过盆栽试验和野外取样,研究施用不同类型肥料和不同用量缓释钾肥B对烤烟农艺性状、光合作用特性、碳氮化合物含量和代谢酶活性、烤烟根尖和茎尖植物激素含量、不同器官的矿质元素含量、烟叶化学成分含量及比值、烟叶产量和产值的影响,以期为提高我国烟叶含钾量和烟草一次性施肥提供一条新途径,并为烟草缓释钾肥的研制、施用和开发提供科学理论依据。结论如下:1.根据湖南省烟草生长发育对养分的需求而设计并研制的五种包膜钾肥（coated potassium fertilizer,CPF）钾素养分的初期溶出率分别为11.12%、10.76%、10.93%、11.31%、10.82%,微分溶出率分别为3.01%、2.71%、1.37%、1.43%和2.58%。包膜钾肥CPF-3和CPF-4钾素养分的初期溶出率小于15%,微分溶出率在0.25%～2.5%之间,符合国际公认的评价缓释肥料养分释放特性的标准,被命名为缓释钾肥A（slow-releasepotassium fertilizer A,SRPF-A）和缓释钾肥B（slow-releasepotassium fertilizer B,SRPF-B）。初始水溶液的pH值对SRPF-B的影响小于SRPF-A,pH 6.0适合钾素养分的释放。温度和肥水比对钾素养分释放的影响较大,从20℃到60℃,温度每升高20℃,缓释钾肥的钾素养分释放速率提高1.32到3.21倍。土壤含水量影响养分的释放和扩散,土壤含水量为75%时,肥料钾素养分的释放速率和累积释放率最大。2.施用SRPF-A和SRPF-B促进烤烟各个生育时期叶片的生长与展开,明显影响烤烟的叶长、株高、茎围和最大叶面积等农艺性状,但是对有效叶片数和叶宽的影响不显著。移栽后45d到75d为烤烟干物质迅速积累时期,其中叶片中干物质积累速率大于根和茎。施用SRPF-B处理干物质的积累量最大,大于分别施用75%SRPF-B、SRPF-M和烟草专用配方肥（tobacco special formulated fertilizer,TSFF）的处理。移栽后45d,烟株根系活力最强。施用SRPF-A、SRPF-B促进根系的生长发育、增加根系的鲜重和体积,促进根系对养分的吸收与运输,改善烟叶的品质。施用SRPF-B的处理的根系活力与其它处理之间差异显著。3.打顶前,施用SRPF-A和SRPF-B提高烟株茎尖和根尖IAA、GA₃、ZR含量,降低ABA含量,其中施用SRPF-B处理的茎尖的IAA、GA₃、ZR含量最高,ABA含量最低。随着生育期的延后,烟株茎尖和根尖的ZR和ABA含量逐渐升高,移栽后45d,烤烟茎尖和茎尖的GA₃含量和IAA含量达到峰值。移栽后30d、45d、60d,施用SRPF-B的处理的茎尖IAA含量分别是同一时期对照茎尖IAA含量的1.85、1.44、1.97倍,为同一时期TSFF茎尖IAA含量的1.16、1.21、1.26倍。施用SRPF-B降低了烟草根系中腐胺和亚精胺的含量,提高了根系内精胺的含量。肥料类型对根系内多胺含量的影响小于施用量对根系多胺含量的影响,根系内腐胺、精胺、亚精胺含量随施肥量的减少而升高。4.施用SRPF-B和75%SRPF-B明显提高生育后期叶片的叶绿素a、叶绿素a/b和总叶绿素含量。移栽后40d以内,施用TSFF处理叶片的硝酸还原酶活力较高,移栽50d以后,施用SRPF-A、SRPF-B提高烤烟生育后期叶片的硝酸还原酶活力,其中SRPF-B的效果优于SRPF-A。烤烟生育前期,施用TSFF处理叶片的蛋白质含量高于施用SRPF-A、SRPF-B的处理,后期则相反。肥料施用量对叶片烟碱含量的影响大于肥料类型,减少SRPF-B的用量降低烟碱的含量,不同叶位叶片烟碱含量的大小为上部叶＞中部叶＞下部叶。随着生育期的延后,总糖和还原糖的含量逐渐增加,施肥明显提高烤烟叶片总糖和还原糖的含量,其中施用SRPF-B和75%SRPF-B,提高还原糖的比例,改善烟叶的品质。5.烤烟生育后期,施用SRPF-B处理各器官的矿质元素含量保持较高的水平,烟叶中的钾含量高于施用SRPF-A、TSFF的处理,但是烟叶中钙镁的含量低于施用SRPF-A、TSFF的处理。随着生育时期的延后,根茎叶中大多数矿质元素的含量逐渐降低。6.施用缓释钾肥提高烤后烟叶中总氮、钾和还原糖含量,降低磷、钙、镁、烟碱和氯含量。施用SRPF-B、SRPF-A处理的总糖和还原糖高于国际型优质烟叶的要求,施用SRPF-B和75%SRPF-B的钾浓度在2.0%以上,施用缓释钾肥提高氮碱比、钾氯比、糖碱比。从烤后烟叶的化学成分含量以及比值的综合分析,以施用SRPF-B和75%SRPF-B处理的烤后烟叶中各种化学成分的含量较适宜,比例较协调。施用SRPF-A、SRPF-B处理的烟叶的产量和产值高于施用烟草专用配方肥的处理。施用75%SRPF-B的处理的产量低于施用SRPF-B的处理,但是烟叶的平均价格高于施用SRPF-B的处理,即适当减少SRPF-B虽然降低的烟叶的产量,但是因为改善了烟叶的品质而提高了烟叶的平均价格,达到“优质适产”的目标。更多还原

【Abstract】 Tobacco is a very important economic crop in China.Crude tobacco and cigarette output from China accounts for 30%and 32%of the world’s production respectively,but the export part only occupies 3.5%and 1.8%of the world’s capacity. In China,The main reason for lower export is the lower quality of crude tobacco caused by the low potassium content in the leaves.Not only the output and production value but also the average price and the ratio of highest quality tobacco leaves are determined by fertilization in present tobacco culture system.So,fertilization,under the conditions of definite environment and varieties,is the key technology to control the output and quality of tobacco leaves.Improving potassium content of tobacco leaves to achieve excellent and optimized tobacco leaves by scientific and economical fertilization are the key methods for tobacco production.The "dissolution rate in water" and "dissolution rate in soil" methods were used to study the potassium nutrient release characteristics of coated potassium fertilizer （CPF） and screen the appropriate types of the slow-release potassium fertilizer （SRPF）.And by pot culture experiments and field sampling,the application effects of different kinds of fertilizer and different dosage of slow-release potassium fertilizer B on agronomic features,photosynthetic characteristics,contents of carbon and nitrogen compounds,enzyme activities relating carbon and nitrogen metabolism, phytohormone contents in root and stem tips,mineral contents in different organs, contents and ratio of chemical components in baked tobacco leaves,output and production values were studied to provide scientific theoretical foundation for manufacture,application and development of tobacco slow-release potassium fertilizers.The results were as follows:1.The potassium nutrient preliminary solubility rate of the five potassium fertilizers,which were designed and manufactured according to nutrient requirement of tobacco during growth and development in Hunan Province,was 11.12%,10.76%, 10.93%,11.31%and 10.82%,and the differential solubility rate of them was 3.01%, 2.71%,1.37%,1.43%and 2.58%respectively.The potassium nutrient preliminary solubility rate of CPF-3 and CPF-4 was less than 15%,and the differential solubility was between 0.25%and 2.5%,which met with the international recognized standard for evaluating the nutrient release characteristic of slow-release fertilizers.Thus, CPF-3 and CPF-4 was named slow-release potassium A and slow-release potassium B respectively.The effect of pH on SRPF-B was smaller than that on SRPF-A,pH 6.0 was found optimal for nutrient release.The effects of temperature and fertilizer-water ratio on potassium nutrient release characteristics were larger than other factors.The potassium nutrient release velocity of SRPFS was increased 1.32～3.21 times with every 20℃from 20℃to 60℃.The nutrient release and spread were affected by soil water content and the potassium nutrient release speed and accumulation content of fertilizers were the greatest when soil water content was 75%.2.The main agronomic features of leaf growth and unfolding,leaf length,height, stem girth and maximum leaf area were remarkably influenced by applying SRPF-A and SRPF-B.The effects of SRPFS on leaf breadth and the numbers of valid leaves were unobvious.It was the rapid dry matter accumulation period 45 to 75d after transplanting.The dry matter accumulation speed in leaves was quicker than that in roots and stems.The order was SRPF-B＞75%SRPF-B＞50%SRPF-B＞tobacco special formulated fertilizer（TSFF）.The activities of root systems were strongest at 45d after transplanting,which was strengthened after topping because the growth centre was changed.The growth and development,fresh weight and volume,nutrient absorption and transportation of root systems,and the quality of tobacco leaves were improved by applying SRPF-A and SRPF-B Applying SRPF-B showed significant difference in root system activities from other treatments.3.IAA,GA₃ and ZR contents in root and stem tips were increased,and ABA decreased by applying SRPF-A and SRPF-Bbefore topping.The IAA,GA₃ and ZR content was highest in SRPF-N treatment,and ABA content was lowest among the treatments.ZR and ABA contents in root and stem tips were increased gradually with growth and development of tobacco,but GA₃ and IAA contents were reached the peak 45 days after transplanting.The IAA content of stem tips in SRPF-B treatment was as 1.85,1.44,1.97 times as that of control and 1.16,1.21,1.26 times as that in TSFF treatment 30d,45d,60d after transplanting respectively.Applying SRPF-B decreased PUT and SPM contents and increased SPD content in root systems.Polyamine content was less affected by kinds than by dosage of fertilizer.Decreasing fertilizer dosage increased PUT,SPM and SPD contents.4.The content of total chlorophyll and chlorophyll a/b at later stage were increased by applying SRPF-B and 75%SRPF-B.The NR activities in TSFF treatment was the highest at 40d after transplant.However,at 50d after transplant,the NR activities in SRPFS treatment were highest,SRPF-B showed better effect than SRPF-A.The content of protein in plant from TSFF treatment was higher than that from SRPF-B and SRPF-A treatment in early stage,but reversed in later stage.The nicotine content was reduced when decreasing dosage of SRPF-B,the order of nicotine content in leaves was topper leaf＞middle leaf＞lower leaf.The content of total sugar and reduced-sugar was increased as growth and development of tobacco, which was enhanced by fertilization.Reduced-sugar/total sugar was increased and quality of tobacco leaves improved by applying SRPF-B and 75%SRPF-B.5.The contents of mineral elements in different organs of tobacco kept on high level at later stage by applying SRPF.K in tobacco leaves was higher in SRPF-B treatment,and Ca and Mg were lower than that in SRPF-A and TSFF treatments. Most of mineral elements in roots,stems and leaves decreased gradually with the growth and development of tobacco plants.6.Increasing K content leaded to decreasing Ca and Mg content in leaves.The content of N,P,K,Ca and Mg reduced gradually as the growth and development of tobacco.The contents of total N,K and reduced-sugar were enhanced,but the contents of P,Ca,Mg,nicotine and chlorine were decreased by applying SRPF. Contents of total sugar and reduced-sugar were higher than the standards.K content was above 2.0%in treatments applying SRPF-B and 75%SRPF-B The N/nicotine ratio,K/Cl ratio and sugar/nicotine were increased by applying SRPF-B. Comprehensive analysis of the contents and ratio of all kinds of chemical constitutions showed that applying SRPF-B and 75%SRPF-B produced the best results.The yield and economic value were higher applying SRPF-A and SRPF-B compared with using tobacco special formulated fertilizer.Although yield in treatment of 75%SRPF-B was lower than that of SRPF-B,the average price of tobacco leaves was higher because the quality of tobacco leaves was improved.Therefore,it is possible to reduce cost and increase income by applying 75%SRPF-B instead of pure in practical production.更多还原