【作者】 黄玉茜；

【导师】 韩晓日；

【作者基本信息】 沈阳农业大学 ， 植物营养学， 2011， 博士

【摘要】 本文以花生作为研究对象,在大田条件下,对不同连作年限花生的农艺性状和产量、光合特性、营养特性、干物质积累与分配和土壤中养分含量进行了全面详细的研究,并通过盆栽试验,运用传统平板培养和现代分子生物学技术,对花生根际、非根际微生物种群随连作茬次的动态变化进行了跟踪研究,同时对花生在不同连作年限下的土壤酶变化作了初步探讨,又系统的研究了花生在连作条件下防御酶系活性以及膜脂过氧化产物含量的变化规律,通过盆栽试验及生物测试,研究了花生植株、花生土壤水浸提液对其种子萌发和幼苗生长的化感效应,并采用HPLC技术,有针对性的检测了不同连作年限花生根际土壤中酚酸类物质的种类及含量,主要研究结果如下：1、随连作年限的增加,花生主茎高、叶绿素相对含量、净光合速率、气孔导度和胞间CO2浓度均呈现逐年下降趋势,连作4年的花生植株百果重和百仁重最低,连作3年花生产量最低。连作对叶绿素相对含量的影响在成熟期时最为明显,叶面积并未呈现出逐年降低趋势,而是在连作3年时达到最低值。随连作年限的增加,花针期时花生茎叶中P、K含量呈现逐年减少的变化趋势,N含量变化不规律。成熟期时果实中N、P、K含量均呈现先降低再升高的趋势。随连作年限的增加,花针期时,植株内的中量元素含量呈现一定的变化趋势,除Cu外,其它中量元素含量在各处理间并无显著差异。其中Ca、Fe变化规律一致,呈现逐年增加的趋势；Mg、Zn变化规律一致,呈现先上升后下降再上升的趋势；Mn含量呈现先下降再上升又下降的趋势；Cu含量呈现先下降后升高的趋势。结荚期时,植株内的中量元素含量也呈现一定的变化趋势,除Mg外,其它中量元素含量在各处理间并无显著差异。其中Ca、Mn、Cu变化规律一致,呈现先下降再上升又下降的趋势；Mg、Fe变化规律一致,呈现先下降后升高的趋势；Zn含量呈现逐年上升的趋势。成熟期时,植株内的中量元素含量也呈现一定的变化趋势,Fe、Cu、Zn含量在各处理间存在显著性差异。其中Ca、Fe的变化规律一致,呈现逐年下降的趋势；Zn、Mn变化规律一致,呈现逐年增加的趋势；Cu含量呈现先下降再上升又下降的变化趋势。结荚期时,Mo含量在各处理间存在着显著性差异,呈现出随连作年限的增加先降低后升高再降低的变化趋势,而B含量在各处理间不存在显著性差异。随连作年限的增加,花针期和结荚期时,花生叶片、茎、根、荚果和全株干物质积累均呈现先下降后升高的趋势；成熟期时呈现先升高后下降的趋势。同一连作年限下,叶片和茎的干物质积累随生育进程的推进而呈现先增加后减少的趋势,最高值出现在结荚期；荚果和全株的干物质积累呈现逐渐增加的趋势,最高值出现在成熟期；根的干物质积累变化无规律。花针期时,连作2年花生的根干重占全株干重的比例较正茬有所减少,茎、叶所占比例增加,根冠比减少；连作3年和连作4年花生的根干重占全株干重的比例较正茬有所增加,茎、叶所占比例减少,根冠比增加。结荚期和成熟期时,花生植株个体干物质在各器官中的分配并不随连作年限的增加而发生大的变化。花生植株个体的干物质在各器官中的分配会随生长中心的转移而变化。2、随连作年限的增加,花生土壤微生物区系出现显著变化,根际及非根际土壤中细菌、放线菌数量减少,真菌数量增加,变化均达到显著水平。根际土壤微生物数量和变化幅度明显高于非根际土壤。根际土壤中氨化细菌为优势细菌生理类群,反硝化细菌和好氧性自生固氮菌次之,硝化细菌最少。氨化细菌、硝化细菌和好氧性自生固氮菌的数量随连作年限的增加而逐年减少,反硝化细菌数量则升高,变化均达到显著水平。不同连作年限根际土壤中的细菌、放线菌和真菌数量随着花生生育进程的推进,基本上均呈现先增加后减少的趋势。DGGE结果显示,不同连作年限根际土壤中存在一些共有的细菌类群,也会出现或缺失个别细菌类群,正茬花生在苗期和结荚期时土壤中细菌群落结构相似性最高。3、随连作年限的增加,花生土壤中过氧化氢酶和碱性磷酸酶的活性在整个生育期内呈现下降趋势；脲酶和转化酶活性呈现先下降后增加再下降的趋势；酸性磷酸酶和中性磷酸酶活性呈现先增加后下降的趋势。不同连作年限土壤中过氧化氢酶活性随着花生生育进程的推进,呈现下降趋势；脲酶活性总体上呈增强趋势；转化酶活性呈先降低后升高的趋势；中性和碱性磷酸酶活性均呈现先升高后下降的趋势；正茬和连作2年两个处理的酸性磷酸酶活性呈现升高趋势,连作4年和连作6年两个处理呈现先升高再降低的趋势。4、0-20cm土层中全氮、碱解氮含量随连作年限的增加在花针期时呈现先增后降再增,结荚期时呈现先增后降的变化趋势；全钾、有效钾含量随连作年限的增加各自呈现独特的变化规律,在花针期和结荚期的每个土层中,全钾含量均呈现先降后增的变化趋势,有效钾则呈现先增后降的趋势；全磷含量随连作年限的增加在不同生育时期表现为不同的变化规律,花针期时每个土层均呈现先增后降的趋势,结荚期时呈现先降后增再降的趋势。有效磷含量则在不同土层中呈现不同的变化规律,0-20cm土层中,随连作年限的增加在花针期和结荚期时均呈现先增后降的趋势,20-40cm土层中,则呈现先降后增再降的趋势。0-20cm土层中有效Fe、Cu、Zn含量随连作年限的增加在花针期和结荚期时呈现相同的变化规律,为先降后增的趋势；有效Ca、Mg、Mn含量在花针期时呈现相同的变化规律,为先增后降再增的趋势。20-40cm土层中,各中量元素的含量均未表现出有规律的变化趋势。有效B含量随连作年限的增加在花针期时每个土层均呈现先增后降的趋势；结荚期时每个土层的变化规律不同,20-40cm土层中呈现先增后降,0-20cm土层中呈现先降后增的趋势。5、随连作年限的增加,花生叶片的过氧化氢酶活性在整个生育期内总体上呈现下降趋势；多酚氧化酶、过氧化物酶、超氧化物歧化酶活性和丙二醛含量在整个生育期内总体上呈现升高趋势；苯丙氨酸解氨酶活性在整个生育期内变化规律不一致,苗期和花针期时,连作3年的酶活性大于正茬花生,结荚期和成熟期时,连作3年的酶活性小于正茬花生。不同连作年限花生叶片过氧化氢酶和过氧化物酶活性随生育进程的推进呈现先升高后下降的趋势；超氧化物歧化酶活性总体上呈现先下降后小幅上升的趋势；正茬花生多酚氧化酶活性呈现先上升后下降趋势,连作3年花生呈现先上升后下降再上升的趋势；正茬花生苯丙氨酸解氨酶活性呈现上升趋势,连作3年花生呈现先缓慢上升后下降再上升的趋势；丙二醛含量总体上呈现上升趋势,但两个处理的变化趋势略有不同。正茬花生从苗期到花针期时表现为大幅度上升趋势,到结荚期时含量有所下降,进入成熟期后又有所上升并达到最高值。连作3年处理的含量则随生育进程的推进逐渐升高,成熟期达到最高值。6、不同浓度的花生根际土壤、茎、叶水浸液对其种子萌发和幼苗生长均存在一定的抑制作用,其作用强度随浸提液浓度的增大而增强。对种子萌发的抑制作用强度顺序为：茎>叶>土壤,对幼苗生长的抑制作用强度顺序为：茎、土壤>叶。不同浓度的花生根际土壤、茎、叶水浸液对花生种子萌发的抑制作用大于对其幼苗生长的抑制作用。从不同连作年限花生根际土壤中均检测到两种酚酸物质,即香草酸和香豆素,其含量均随连作年限增加而呈现累积的趋势。香草酸含量显著高于香豆素。连作6年后土壤中两种酚酸总含量达到0.314μg.g-1干土,高于连作4年及2年土壤中的含量,且显著高于正茬土壤。更多还原

【Abstract】 In this paper, we choosed the peanut as the research object to comprehensively study the effect of different planting years on agronomic characters and yields, photosynthetic and nutrition characteristic, dry matter accumulation and distribution, soil nutrient content in field conditions. Effect of different planting years on the microbial populations of rhizosphere and bulk soil were tracking studied with the pot experiments, traditional flat training and modem molecular biology technology, meanwile, the effect of different planting years on the soil enzymes were explored for the first time. The change rule of defense enzyme activity and MDA content under continuous cropping were systematically researched. Allelopathic effects of peanut plant and soil extracts on the its seed germination, plants growth were studied with the pot experiments and biological testing. Phenolic acid contents in peanuts rhizosphere soil of different planting years were targetedly detected which using the HPLC. The major findings are as follows:1. The plant height, chlorophyll relative content, Pn, Gs and Ci had been declined with the increasing length of continuous cropping system. The pods and nuts weight reached lowest at planting four years, and the yields reached lowest at planting three years. Continuous cropping influenced on the chlorophyll relative content and this influence of most evident when at matrrity. Leaf area did not show trend to decrese, but reached lowest at planting three years.When blossom stage in peanut stem and leaf, the P, K content had been reduced chage trend with the increasing length of continuous cropping system, N content changes not rule. When maturing stage in fruit, the N, P, K content were significantly the trend which reduce first and rise again.The content of medium elements at blossom stage presented certain change trend with the increasing length of continuous cropping system. Except Cu, the others had no significant differences among four treatments. Among them, the change laws of Ca, Fe were consistent which the trend had been increased. The change laws of Mg, Zn were consistent which rise first then reduce and rise again. The content of medium elements at pot-setting stage presented certain change too. Except Mg, the others had no significant differences among four treatments. Among them, the change laws of Ca, Mn, Cu were consistent which reduce first then rise and reduce again. The change laws of Mg, Fe were consistent which reduce first and rise again. The content of medium elements at maturing stage presented certain change too. Fe, Cu, Zn content had significant differences among four treatments. Among them, the change laws of Ca, Fe were consistent which the trend had been decreased. The change laws of Zn, Mn were consistent which the trend had been increased.Mo content had significant differences among four treatments at pot-setting stage. The change trend was presented that reduce first then rise and reduce again with the increasing length of continuous cropping system.At blossom and pot-setting stage, the leaf, steam, root, legume and all organs of peanut dry matter accumulation presented the change trend which reduce first and rise again with the increasing length of continuous cropping system, but its presented the change trend which rise first and reduce again at maturing stage. Under the same continuous fixed number of year, the leaf and steam of peanut dry matter accumulation presented the change trend which rise first and reduce again along with the development of growth period, peak appeared in the pot-setting stage. The legume and all organs of peanut dry matter accumulation presented the change trend which increased, peak appeared in the maturing stage.The root proportion of planting two years decreased compared planting one year, but the proportion of steam and leaf increased, and root-shoot ratio decreased at blossom stage. The root proportion of planting three and four years increased compared planting one year, but the proportion of steam and leaf decreased, and root-shoot ratio increased. At pot-setting and maturing stage, the distribution of peanut dry matter in various organs did not change obviously with the increasing length of continuous cropping system, and it would change with the growth center transferring.2. The soil microflora of peanuts significantly changed, the bacteria and actinomycete quantities obviously decreased, the fungi quantities obviously increased with the increasing of the continuous cropping years. The microbial population and variation in rhizosphere soil were significantly higher than bulk soil. Ammonifying bacteria was the predominant population in rhizosphere soil, denitrifying bacteria and aerobic nitrogen-fixing bacteria less than it, and nitrifying bacteria was the leastest. The number of ammonifying bacteria, nitrifying bacteria and aerobic nitrogen-fixing bacteria presented the change trend which decreased with the increasing of the continuous cropping years, however, the number of denitrifying bacteria presented the change trend which increased. Under the same continuous fixed number of year, the bacteria, actinomycete and fungi quantities presented the change trend which rise first and reduce again along with the development of growth period. DGGE showed that there existed some common bacteria groups in soil among four treatments, and also could appear or lack individual bacteria groups. Soil bacteria community structure similarity was highest between the seeding stage and the pot-setting stage of planting one years.3. The soil catalase and alkaline phosphatase activity presented the change trend which decreased with the increasing of the continuous cropping years. The urease and invertase activity presented the change trend which reduce first then rise and reduce again. The acid and neutral phosphatase activity presented the change trend which rise first and reduce again. Under the same continuous fixed number of year, the soil catalase activity presented the change trend which decreased along with the development of growth period, and the urease activity presented the change trend which increased, the invertase activity presented the change trend which reduce first and rise again, the neutral and alkaline phosphatase activity presented the change trend which rise first and reduce again.4. At blossom stage the content of total and available N presented the change trend which rise first then reduce and rise again in 0-20cm with the increasing of the continuous cropping years, it presented the change trend which rise first and reduce again at pot-setting stage. At blossom and pot-setting stage, the content of total K presented the change trend which reduce first and rise again in two soil strata, the content of available K presented the change trend which rise first and reduce again. At blossom stage, the content of total P presented the change trend which rise first and reduce again in two soil strata. At pot-setting stage, it presented the change trend which reduce first then rise and reduce again. At blossom and pot-setting stage, the available P presented the change trend which rise first and reduce again in 0-20cm, and it presented the change trend which reduce first then rise and reduce again in 20-40cm.At blossom and pot-setting stage, the change laws of Fe, Cu, Zn were consistent and presented the change trend which reduce first and rise again in 0-20cm with the increasing of the continuous cropping years. The change laws of Ca, Mg, Mn were consistent and presented the change trend which rise first then reduce and rise again. At blossom stage, the content of B presented the change trend which rise first and reduce again at every soil strata with the increasing of the continuous cropping years, but the change rule were different in two soil strata at pot-setting stage. It presented the change trend which rise first and reduce again in 20-40cm, and presented the change trend which reduce first and rise again in 0-20cm.5. The CAT activity of peanut leaf presented the change trend which decreased, and PPO, POD, SOD activity and MDA content presented the change trend which increased with the increasing of the continuous cropping years. The PAL activity changed not regularly. Under the same continuous fixed number of year, the CAT and POD activity presented the change trend which rise first and reduce again along with the development of growth period, the SOD activity presented the change trend which reduce first and rise again. The PPO activity of planting one year presented the change trend which rise first and reduce again, and the PPO activity of planting three years presented the change trend which rise first then reduce and rise again. The PAL activity of planting one year presented the change trend which increased, and the PAL activity of planting three years presented the change trend which rise first then reduce and rise again. As a whole, the MDA content presented the change trend which increased, but there change trend was somewhat different in two treatments. The MDA content presented the change trend which greatly increased from seedling to blossom stage, and declined at pot-setting stage, increased and achieved peak at maturing stage in planting one year. It presented the change trend which gradually increased in planting three years along with the development of growth period, peak appeared in the maturing stage.6. Different concentrations of peanut soil, steam and leaf extracts could cause the inhibition of seed germination and seedling growth of peanut. Its inhibition intensity with the increase of extracts concentration enhanced. The order of inhibition of seeds germination was: steam>leaf>soil; the order of inhibition of seedling was:steam, soil>leaf. The inhibition of seeds germination was greater than of seedling.Two kinds of phenolic acids material were detected from all treatments which were vanillic acid and coumarin, and its content both presented accumulation of trend with the increasing of the continuous cropping years. The content of vanillic acid was significantly higer than the coumarin in soil. The total content of two kinds of phenolic acids material were 0.314μg.g-1dry soil in planting six years, which higher than the total content in planting two and four years, and significantly higer than its in planting one year.更多还原