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药用植物连作障碍研究评述和发展透视 总被引：2，自引：0，他引：2
连作障碍作为现代农业生产中较普遍的问题,在药用植物栽培生产中表现尤为严重,据统计约70%以块根类入药的药用植物在种植过程中都存在严重的连作障碍问题。连作障碍已经成为制约药用植物品质和发展的关键性因素。本研究从药用植物连作障碍问题研究现状出发,分析了当前药用植物连作障碍形成的三大共性问题,即根系分泌物诱导根际土壤酸化、根际微生物群落结构失衡和植株病毒病严重,具体体现在:根系分泌物诱导根际土壤微生物差异性演化、土传病原菌的化感互作、根际微生物区系的失衡加大土壤酸化、根际病原菌增多和有益菌减少导致的土存真菌病害加重、病毒病伴生和发展。并分析了土壤灭菌法、功能微生物调控、作物多样性栽培和生物质炭改良的根际调控策略在减缓药用植物连作障碍中的潜在作用。作者呼吁从事连作障碍研究的工作者应重视从根际生态学角度出发,以土壤食物网为切入点,应用现代系统生物学和化学生态学技术与方法,全面系统探究根系分泌物介导下植物-土壤-微生物的相互作用过程与机制,并着重关注土壤线虫和土壤病毒在连作障碍发生发展中的生态位关系,以深入阐明连作介导土壤酸化的生态学机制和病原菌响应根系分泌物的协同进化机理,在此基础上,采用多种根际调控相结合的策略减缓连作障碍问题,全面考虑经济、社会和生态效益,做到"生态预防为主、综合治理为要"。 相似文献
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低产水稻土改良与管理研究策略 总被引：2，自引：1，他引：2
我国耕地后备资源极端缺乏,改良低产田是提高粮食产量的重要途径。低产水稻土作为低产田的重要组成部分,相关肥力特征及其改良技术研究比较零散,缺乏系统科学的调控管理策略。本文从低产水稻土类型、新的改良研究方法角度,探索可能的技术突破。基于农业部统计数据,因环境条件不良或土壤自身存在障碍因素,全国约有7.67×106hm2低产水稻土。按其主导成因,低产水稻土可分为冷潜型、粘结型、沉板型、毒质型四类。土壤质量评价是低产水稻土研究的重要方面,其评价方法主要包括土壤质量动力学法、土壤质量综合评分法、多变量指标克立格法、土壤相对质量评价法,现已发展了基于GIS的区域尺度水稻土质量评价方法,以及基于土壤生物学性状的质量评价方法。低产水稻土改良研究更多关注新技术和新方法,稳定性同位素探针技术、傅里叶变换红外光谱法(FTIR)和固相交叉极化魔角自旋13C核磁共振(CPMS13C-NMR)波谱技术的应用,将土壤有机碳的微团聚体分布、腐殖质的转化及其与土壤矿物结合机制深入到微观水平;同时高通量测序、土壤宏基因组学、宏转录组学等方法将相关研究推向分子水平。低产水稻土改良与管理的技术主要涉及到冷潜型、粘结型、沉板型、毒质型四大类低产水稻土的改良技术,基于产量反应和农学效率的推荐施肥方法是水稻土养分管理方法的重要发展方向。1)在低产水稻土质量评价方面,未来要结合不同低产类型的障碍因素开展个性化的土壤质量评价,如白土的质地和耕层厚度,加强引入土壤生物学指标进行土壤质量评价研究。2)在低产水稻土改良方面,要研究稻田障碍层次的形成机理与调控途径;研究其他低产类型如新垦水稻土、盐渍化水稻土、石灰化水稻土和污染水稻土的改良技术;研究长期改良措施对不同粒级团聚体腐殖质结构、酶类、微生物多样性和功能基因的影响。3)在低产水稻土管理方面,着重研究秸秆还田技术、推荐施肥技术、抗逆品种技术、群体控制技术。 相似文献
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花生连作土壤障碍机制研究进展 总被引：9，自引：2，他引：9
花生是我国主要经济作物和油料作物,连作障碍问题严重影响花生的产量与品质,制约着我国花生产业可持续发展。已有研究认为自毒物质积累、病菌增加、土壤微生物群落失衡及土壤理化性质恶化是花生连作障碍的主要因子,但大多停留在单因子水平上,有的认识缺乏直接的证据。本文简要综述了花生连作障碍的危害、机制及调控措施,结合作者近几年来相关研究,主要从花生根系分泌物效应、化感物质存留特征、土壤生物群落演变等方面介绍了花生连作障碍机制研究进展,最后对花生连作障碍的进一步研究及防控技术发展方向提出展望。 相似文献
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我国华南地区不同利用条件下土壤演变对障碍因子的影响 总被引：1，自引：0，他引：1
华南地区不同土壤利用条件下土壤性质演变和障碍因子的识别,对该地区土壤发生过程和管理利用有重要参考价值。本文根据中国土壤系统分类的检索原则,在收集华南9省土种志典型剖面资料的基础上,确定了系统分类的土壤类型,并基于此,研究了不同利用条件下,土壤性质的演变,分析了土壤障碍因子及其影响程度。总的来看,发育在林地条件下的土壤,粉粒、pH、阳离子交换量(CEC)、盐基饱和度(BS)、速效磷、速效钾都明显低于旱耕地土壤,有机质、全氮则相反。林地土壤随着风化作用增强,从雏形土、淋溶土、富铁土到铁铝土,土壤黏粒含量逐渐增加,而土壤pH、CEC、有效CEC(ECEC)、有机质、全氮、速效磷、速效钾等逐渐降低。对旱耕地而言,各种土壤性质基本具有与林地土壤性质一致的变化趋势,但是增加或减少的程度有所不同。结合主成分中土壤性质的组合特征来分析土壤障碍,结果表明华南地区土壤在不同土壤利用和类型下都存在养分贫瘠化、酸化、黏化、磷和钾供应能力低下的主要障碍因子,但各障碍因子发生的次序不同,随着风化作用加强,土壤黏化成为最主要的障碍因子。因此,在土壤利用和管理过程中应因土制宜,根据土壤类型来确定适当的改良措施。 相似文献
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为探索近年来国内土壤酸化研究的热点与发展趋势,以CNKI数据库为基础,采用统计与聚类等分析方法,借助CiteSpace信息可视化软件及文献计量学知识,统计并绘制有关国内土壤酸化研究文献的机构、关键词、文献被引频次等信息图表,挖掘土壤酸化研究的整体发展趋势、高产机构、高频关键词等信息。研究发现我国土壤酸化研究的主题从森林土壤逐渐转移至农田土壤,酸沉降及土壤化学在土壤酸化研究中一直属于重点关注对象。研究机构主要集中在高校和科研院所,同时高频关键词显示国内土壤酸化研究主要集中在酸沉降、施肥管理、土壤结构、作物生长、酸化成因及改良、连作障碍及土壤污染等方面。该研究有助于全面了解国内土壤酸化研究现状及进展,为农田土壤酸化改良方面的研究及应用提供重要参考。 相似文献
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中低产田是指土壤存在一种或几种制约农业生产的障碍因素,农业单产相对低而不稳的耕地。研究和分析甘肃省中低产田的现状及其改良技术措施,有针对性地实施中低产田改良改造,对改善甘肃省的农业生产条件和生态环境,提高土地产出率和经济效益,具有重要而深远的意义。针对甘肃省中低产田面积大、分布广和相对集中的特征,在分析中低产田障碍因素成因和主要类型的基础上,梳理了近年甘肃省主要的中低产田改良集成技术措施及其应用效果,提出了中低产田改良和治理的对策建议。 相似文献
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本文从系统的观点出发,分析了能源的供应、需求、技术、经济分析方法,政策法规以及社会习俗诸因素对新能源商品化进程的影响。分析表明:能源的供应与需求矛盾是新能源商品化发展的主要动力,而其它因素构成了影响新能源进入商品市场的障碍层。目前,在我国能源供需矛盾较突出的情况下,如果对障碍层中的诸要素采取适当的措施来减少新能源的发展阻力,就有可能使某些新能源进入实用阶段。 相似文献
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基于产量的稻田肥力质量评价及障碍因子区划——以进贤县为例 总被引：5，自引：0，他引：5
土壤肥力质量评价及土壤肥力障碍因子分析,对于区域土壤利用和改良、指导农业生产结构布局具有重要意义。以江西省进贤县为研究区,通过水稻遥感解译测产,结合主成分分析进行土壤质量评价;采用综合指数法表征土壤肥力质量水平,分析该区域低肥力质量区域主要障碍因素,并进行障碍因子区划。结果表明,该地区土壤肥力质量评价的最小数据集(MDS)指标包括:有机质、阳离子交换量(CEC)、全钾(TK)、交换性钙(Ex.Ca)、容重、粉黏比;土壤质量综合指数与水稻产量相关系数达到0.73(p0.01),以当地水稻平均产量7.215 t hm~(-2)确定土壤质量综合指数阈值为0.65。分析得出,该地区影响土壤肥力的主要障碍包括有机质含量低和容重较大反映的低熟化度障碍、中量元素缺乏反映的酸化障碍、全钾含量低和高粉黏比反映的结构障碍等。根据障碍因素将研究区域划分为三大障碍区:东南部丘陵区主要障碍因子为酸化和土壤结构障碍;中西部低岗平原主要为土壤酸化障碍;北部滨湖区主要障碍为水稻土熟化程度低。通过对不同区域施行针对性改良措施有益于提高土壤肥力。 相似文献
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【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
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Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
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《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
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M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献
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Grete Skrede Berit Karoline Martinsen Anne-Berit Wold Stein-Erik Birkeland Kjersti Aaby 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):193-208
Abstract A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(7):865-877
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils. 相似文献
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Y. Bashan J. J. Bustillos L. A. Leyva J.-P. Hernandez M. Bacilio 《Biology and Fertility of Soils》2006,42(4):279-285
Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several
photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene.
This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments
for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference
in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless
of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots.
Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production
or the positive response of the plants towards A. brasilense Cd inoculation. 相似文献
18.
Dhritiman Ghosh Velusamy Srinivasan Olli H. Tuovinen Aaron Peacock Mark Radosevich 《Soil biology & biochemistry》2009,41(6):1331-1334
We examined the community composition of microbes that colonized atrazine-containing beads buried in agricultural soils that differed in atrazine treatment history. Bacterial abundance was 5-40-fold greater in atrazine-fortified beads. In beads containing 20 mg atrazine kg−1 buried in soil with a history of atrazine application (conditioned soil), the abundance of Actinobacteria increased approximately 80-fold whereas in control soil, Actinobacteria were enriched only 10-fold and the gamma-Proteobacteria and Planctomycetes increased by 60- and 25-fold, respectively. The gamma-Proteobacteria were enriched by 120- and 230-fold in beads containing 200 mg atrazine kg−1 in conditioned and control soil, respectively. The results demonstrate that BioSep® beads are a suitable matrix for recruiting a diverse subset of the bacterial community involved in atrazine degradation. 相似文献
19.
Pilar García Juan-Vicente Monte Carlos Casanova Consuelo Soler 《Genetic Resources and Crop Evolution》2002,49(1):103-109
Arbitrary oligonucleotides were used as primers to amplifygenomic DNA of 48 wild Spanish populations of Agropyroncristatum, Elymus hispanicus,E. caninus,E. repens,Thinopyrum curvifolium, Th.junceum and Th.intermedium. Genetic diversity was analysedusing nineteen primers. The number of amplified products ranged from8 to 18 per primer and a total of 240 markers were scored. Differentlevels of intraspecific genetic diversity were found, the allogamousspecies E. repens andTh. intermedium being themost variable. Jaccard's similarity coefficients for internalmeasure within and between populations were used to produce a clusterdiagram. The results demonstrate differences in the degree ofsimilarity between taxonomic units. Interpopulational variability andinterspecific genomic relationships of these species arediscussed. 相似文献
20.
The effects of three commonly used fungicides on the colonization and sporulation by a mixture of three arbuscular mycorrhizal (AM) fungi consisting of Glomus etunicatum (Becker & Gerd.), Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe, and Gigaspora rosea (Nicol. & Schenck) in symbiosis with pea plants and the resulting response of the host-plant were examined. Benomyl, PCNB, and captan were applied as soil drenches at a rate of 20 mg active ingredient kg-1 soil 2 weeks after transplanting pea seedlings in a silty clay-loam soil containing the mixed inocula of AM fungi (AM plants). Effects of fungicides were compared to untreated plants that were inoculated with fungi (AM control). The effect of mycorrhizal inoculation on plant growth was also examined by including nonmycorrhizal, non-fungicide-treated plants (non-AM control). Fungicides or inoculation with AM fungi had only a small effect on the final shoot weights of pea plants, but had greater effects on root length and seed yield. AM control plants had higher seed yields and lower root lengths than the corresponding non-AM plants, and the fungicide-treated AM plants had intermediate yields and root lengths. Seed N and P contents were likewise highest in AM control plants, lowest in non-AM plants, and intermediate in fungicide-treated AM plants. All three fungicides depressed the proportion (%) of root length colonized by AM fungi, but these differences did not translate to reductions in the total root length that was colonized, since roots were longer in the fungicide-treated AM plants. Pea plants apparently compensated for the reduction in AM-fungal metabolism due to fungicides by increasing root growth. Fungicides affected the population of the three fungi as determined by sporulation at the final harvest. Captan significantly reduced the number, relative abundance, and relative volume of G. rosea spores in the final population relative to the controls. The relative volume of G. etunicatum spores was greater in all the fungicide-treated soils, while G. mosseae relative volumes were only greater in the captan-treated soil. These findings show that fungicides can alter the species composition of an AM-fungal community. The results also show that AM fungi can increase seed yield without enhancing the vegetative shoot growth of host plants. 相似文献