玉屏县土壤主要肥力指标的分析与评价

为了指导贵州省玉屏县的农业生产,通过对贵州省玉屏县的533个土壤样品进行养分含量测定和统计分析,评价了玉屏县土壤的酸碱度状况和主要肥力指标。结果表明:玉屏县土壤pH平均值为6.65,土壤有机质、土壤全氮、碱解氮、速效磷、速效钾和缓效钾的平均含量分别为26.16 g/kg,1.57 g/kg,134 mg/kg,14.4 mg/kg,149 mg/kg,296 mg/kg。大部分土壤pH近中性偏碱,全氮和碱解氮总体含量处于较高水平,有机质、速效磷和速效钾含量总体处于中等水平,而缓效钾含量水平偏低。各种营养元素的变异程度由小到大依次为土壤碱解氮、全氮、有机质、速效钾、缓效钾、速效磷。为此初步提出了调控土壤酸碱性、稳定土壤有机质、减氮、适磷、补钾的施肥建议。     

基于GIS和地统计学的黔西北农业园区土壤养分空间变异特征研究

以黔西县水西观光农业示范园区(乌骡坝社区)为研究区域,采用地统计学方法,研究了黔西北山区土壤pH值、有机质、碱解氮、有效磷、速效钾、全氮、全磷、全钾的土壤养分状况及空间变异规律。结果表明：(1)土壤pH值表现为弱变异性,其余各项指标变异均属于中等程度变异;(2)土壤pH、有机质、碱解氮、有效磷、速效钾和全氮均是中部分布较低,全磷是中部分布较高,有机质是北部和南部分布较高;速效钾是东部分布较高,全氮和全钾北部分布最高;(3)土壤有机质C0 /(C0 +C)=31.935%,表现为中等空间相关性,其余各土壤养分指标均表现为强烈的空间相关性。     

玉龙纳西族自治县土壤肥力分级及评价

为了指导云南省玉龙县的农业生产实践,通过对云南省玉龙县的216个土壤样品进行含量测定和统计分析,分析与评价玉龙县土壤的酸碱度状况和主要肥力指标。结果表明：玉龙县土壤pH平均值为7.08,土壤有机质、土壤全氮、碱解氮、速效磷、速效钾和缓效钾的平均含量分别为17.12 g/kg,1.83 g/kg,134.67 mg/kg,16.75 mg/kg,139.10 mg/kg,896.56 mg/kg。大部分土壤pH近中性偏碱,速效磷总体含量处于中等水平,全氮和碱解氮含量总体处于中等水平,而有机质、速效钾和缓效钾含量水平较高。各种营养元素的变异程度由小到大依次为土壤碱解氮、有机质、速效钾、缓效钾、全氮、速效磷。为此初步提出了调控土壤酸碱性,稳定土壤氮磷、适当增施有机肥、钾肥的施肥建议。     

河套平原典型县域耕地土壤养分空间变异特征研究

为研究河套平原地区土壤养分状况,探究县域尺度土壤养分的空间变异性与分布特征,以杭锦后旗县域耕地为对象,采用实地调查和地统计学相结合的方法,研究该区耕层土壤有机质、全氮、有效磷、速效钾养分含量状况,分析土壤养分空间分布及其变异特征。结果表明,研究区耕层土壤有机质、全氮、速效磷和速效钾平均含量依次为13.90 g/kg、0.93 g/kg、16.25 mg/kg和170.79 mg/kg,土壤有机质和全氮处于缺乏状态,速效磷含量中等,而速效钾的含量较为丰富。从空间变异及相关性看,各土壤养分的变异程度都为中等变异,有机质和速效钾为中等相关性,全氮和有效磷均为弱相关性。从空间分布格局看,土壤有机质与全氮分布规律相近,呈现西北部高、东南部和东北部低的特点;土壤速效钾整体分布较为均衡;速效磷空间差异明显,呈东高西低格局。针对该地区土壤养分含量及分布规律,在进行养分管理过程中,应以控氮、稳磷、稳钾、全区规划与重点应对相结合的原则,坚持以有机肥为主、有机与无机相结合的施肥策略。对县域尺度耕地土壤养分状况的调查研究和统计分析,明晰了区域土壤养分空间分布特征及其与土地利用方式之间的关系,为河套平原耕地土壤养分管理、地力培育以及合理施肥运筹等提供科学依据。     

宁蒗县土壤主要肥力指标的分析与评价

为了指导云南省宁蒗县的农业生产实践,通过对云南省宁蒗县的201个土壤样品进行含量测定和统计分析,分析与评价宁蒗县土壤的酸碱度状况和主要肥力指标。结果表明：宁蒗县土壤pH平均值为6.77,土壤有机质、土壤全氮、碱解氮、速效磷、速效钾和缓效钾的平均含量分别为12.51 g/kg,0.93 g/kg,93.83 mg/kg,25.19 mg/kg,43.86 mg/kg,157.28 mg/kg。大部分土壤pH近中性偏酸,速效磷总体含量处于较高水平,全氮和碱解氮含量总体处于中等水平,而有机质、速效钾和缓效钾含量水平偏低。各种营养元素的变异程度由小到大依次为土壤速效钾、缓效钾、有机质、碱解氮、全氮、速效磷。为此初步提出了调控土壤酸碱性,稳定土壤氮磷、适当增施有机肥、钾肥的施肥建议。     

黑龙江食品安全示范区农田土壤养分空间变异研究

以面积为450000m2农田为采样区,使用手持式GPS定位,网格法采集0~20cm耕层土壤样品,实验室测定土壤碱解氮、速效磷、速效钾和有机质的含量。应用传统统计学方法和空间分析方法对土壤养分变异进行了研究。结果表明,土壤养分性质均存在着空间变异性,受常规施肥措施影响较大的碱解氮、速效磷、速效钾变异相对较大;常规施肥有机质投放较少,变异相对较小;土壤养分性质均存在半方差结构,分别拟合Circular、Pentaspherical、Exponential模型,碱解氮、速效磷、速效钾和有机质均显示中等的空间相关性。     

山西省孝义市麦田土壤养分分布规律研究

采用网格取样的方法,在孝义市采集共2413 个土壤样本,涵盖全市共3 个土壤类型5 个亚类,对土壤样品的有机质、全氮、碱解氮、速效钾、缓效钾、有效磷及有效态中微量元素等养分含量进行了测定与分析,以阐明孝义市麦田土壤的养分分布特征,指导孝义市科学合理施肥。研究结果表明：土壤有机质在不同亚类土壤的平均含量为8.86~23.26 g/kg,处于中等或缺乏水平,碱解氮为76.79~89.47 mg/kg,处于中等水平,有效磷为9.46~15.79 mg/kg,处于较丰富或中等水平,速效钾为139.11~207.74 mg/kg,处于较丰富、丰富或很丰富水平。这些养分在不同亚类土壤中的含量均存在显著差异,总体表现为在盐化潮土中最高,其次是石灰性褐土,在潮褐土、褐土性土、典型红粘土中含量比较低。在不同土壤亚类中,有机质、全氮和有效磷变异系数较高,而碱解氮、速效钾与缓效钾的变异则很低。而各有效态中微量元素的养分含量在不同亚类土壤中的规律则不甚一致,总体来说,除有效硼处于较低水平外,有效锰、有效铁、有效铜、有效锌均处于中等或高水平,且各有效态微量元素养分含量的变异都很低。在测土配方施肥中,应针对这些养分的分布特征,采取养分收支基本平衡策略进行优化施肥,以实现孝义市农业的可持续健康发展。     

芒市耕地土壤肥力特征及变化趋势分析

为揭示芒市耕地土壤养分变化特征,利用2009年测土配方施肥项目中耕地地力调查数据与全国第二次土壤普查数据及肥力分级标准进行分析研究。结果表明：单项指标,pH显微酸性、酸性的面积较大,且土壤表现出酸化趋势;有机质、全氮、碱解氮含量中等、丰富水平的面积较大,但总体含量水平趋于下降;速效磷、速效钾含量缺乏、甚缺水平的面积较大,表现出大面积磷、钾不足,但速效磷含量有所上升,速效钾含量有所下降。芒市耕地土壤总体表现出微酸,有机质、全氮、碱解氮中等偏丰富,速效磷、速效钾缺乏,旱作土养分高于水稻土;区域间养分变化不一致,差异较大;耕地土壤肥力整体在下降。     

福建南平不同植烟土壤微生物数量与养分状况分析

为探究福建省南平地区不同质地土壤中微生物数量与土壤养分状况,对南平地区不同质地植烟土壤pH、土壤养分含量（有机质、全氮、碱解氮、全磷、速效磷、全钾、速效钾）和土壤微生物数量（细菌、真菌、放线菌、解磷菌、解钾菌、纤维素分解菌）进行测定。实验结果：供试南平地区不同质地植烟土壤pH均偏酸（pH均小于5.5）,不同质地土壤中粘土的有机质、全氮、碱解氮含量最多,其次是壤土和砂土。植烟土壤中微生物以细菌为主,其次是放线菌和真菌。对不同质地土壤养分与微生物数量相关性分析,得出南平地区土壤样品中细菌与全磷、速效磷、全钾、速效钾相关性较高;真菌与全钾、全磷、速效磷呈负相关,与有机质、全氮、碱解氮、速效钾呈正相关,与全钾显著相关;放线菌与速效磷显著相关;解磷菌与土壤多种养分呈正相关,但相关系数不高;钾细菌与速效磷显著相关,与全磷含量极显著相关;纤维素分解菌与碱解氮相关性最高,与速效钾、全磷、速效磷呈负相关。这些相关性分析表明,南平地区不同质地植烟土壤微生物数量与土壤养分含量虽呈一定的相关性,但相关系数不高,说明该地区的气候条件、施肥方式,特别是水稻—烟草的轮作方式也是影响微生物的数量和种类的重要因素。本研究是对南平地区植烟土壤信息的必要补充,也为今后如何合理利用菌肥,有目的地地开发南平地区植烟土壤的功能菌提供了实验基础和理论依据。     

云南景迈山和六大茶山古茶园土壤养分分析

为弄清景迈山和六大茶山古茶园土壤养分状况,为更好地保护和利用古茶园提供科学依据,用油浴加热重铬酸钾氧化-溶量法和碱解扩散法等方法测定古茶园土壤有机质、碱解氮、速效磷和速效钾的含量。结果表明,景迈山古茶园土壤有机质和速效磷平均含量均较六大茶山高,而碱解氮和速效钾平均含量均较六大茶山低,景迈山古茶园土壤均达到Ⅰ级茶园土壤标准,六大茶山古茶园土壤均达到Ⅱ级茶园土壤标准。景迈山土壤养分含量变异系数由大到小依次为速效磷>碱解氮>速效钾>有机质,六大茶山土壤养分含量变异系数由大到小依次为速效磷>速效钾>碱解氮>有机质,其中景迈山有机质和碱解氮均较六大茶山大,而速效磷和速效钾均较六大茶山小。LSD多重比较表明,景迈山和六大茶山共16个地方古茶园土壤有机质、碱解氮、速效磷和速效钾的平均含量差异显著。     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Evolution under domestication involving disturbance of genic balance

Summary An hypothesis is developed that the rapid change from wild plants into domesticated crops principally involves the selection of alleles with non-functional gene products which leads to reduced control of the highly integrated metabolism and morphogenesis previously accumulated by lengthy natural selection. Such disturbance of the genome produces altered physiological and morphological development which, although deleterious in nature, serves mankind better and has been selected.     

Genetic variation for disease and nematode resistances and forage quality in perennial diploid and tetraploid lucerne populations (Medicago sativa L.)

Summary Twenty-five lucerne populations of the Medicago sativa complex, which were either diploid or tetraploid and wild or cultivated, were analysed for their resistance to four different fungal diseases and to stem nematode. Forage quality, including stem digestibility and saponin content, was also tested.Populations varied in susceptibility to the diseases caused by Colletotrichum trifolii, Verticillium albo-atrum, Sclerotinia trifoliorum and Pseudopezizza medicaginis, and to the nematode Ditylenchus dipsaci. Except for Sclerotinia rot, sativa and falcata subspecies differed in susceptibility, but this grouping of populations did not account for the full range of variation among them. However, the resistance to P. medicaginis was much lower in the sativa than in the falcata populations.Populations also varied significantly in stem fiber content and digestibility. Stem digestibility was negatively correlated to forage yield. Wild sativa and falcata populations had lower fiber content and higher digestibility than cultivated sativa populations. The medicagenic acid was the sapogenin responsible for the anti-nutritional effect of the lucerne measured by the yellow mealworm larvae Tenebrio molitor. The medicagenic acid content was lowest for the pure sativa populations, highest for the pure falcata populations, and intermediate for the French sativa varieties that have some traits originating from falcata germplasm. Some populations could be used in breeding programs to improve disease and nematode resistance, and forage quality.     

Review of Effects of Active Components of Gastrodiae Rhizoma on Central Nervous System

In order to explore the pharmacological effects of active components of Gastrodiae Rhizoma on the central nervous system,through consulting related literatures,...     

Effects of Pb on Rhizosphere Soil Enzyme Activity and Chemical Constituents of Achyranthes bidentata Blume

[Objectives]The purpose of this study was to investigate the effects of Pb on rhizosphere soil enzyme activity and chemical constituents of Achyranthes bidentat...     

不同P-Zn配比对小麦幼苗微量元素营养的影响

采用了螯合-缓冲营养液培养方法对小麦进行了苗期培养试验,在3个P水平(0,0.6,3.0 mmol/L)和3个Zn水平(0,3,30 μmol/L)的完全组合下对小麦苗期生长及Zn、Fe、Cu、Mn营养进行了研究,旨在为小麦微肥施用提供理论依据.结果表明,P、Zn的正常供应促进了小麦生长,二者的缺乏与过量均会抑制小麦发育,且这种影响在冠部表现得更为明显.在小麦苗期,Zn与Cu的吸收存在明显的拮抗作用,但供Zn则促进了Zn和Cu的转运,而Mn转运则受到了抑制;过量供Zn时,大量Zn被转运到冠部,同时明显抑制了(Fe+Cu+Mn)的吸收总量;P的供应显著地抑制了Fe的吸收,但P的供应提高了Zn、Cu、Mn的转运率;P、Zn在对Zn与Fe、Cu、Mn间吸收竞争的影响中,Zn本身的影响要比P的影响更为明显,供Zn明显促进了小麦幼苗对Zn的吸收;在小麦幼苗冠部,Zn与Fe的竞争中,供P利于Zn的吸收,缺P则利于Fe的吸收;而Zn与Cu以及Zn与Mn间的竞争中,缺磷时利于Zn的吸收,供磷后则利于Cu和Mn的吸收.总之,小麦幼苗Zn、Fe、Cu、Mn营养中,P、Zn的不同配比会不同程度地改变Zn与Fe、Cu、Mn的协同或拮抗效应.     

Isozyme variation between diploid and tetraploid cytotypes of Glycine tabacina (Labill.) Benth.

Summary Glycine tabacina (Labill.) Benth. is a wild perennial species related to the cultivated soybean, G. max (L.) Merr. It is composed of diploid (2n=40) and tetraploid (2n=80) cytotypes. Currently, to differentiate the cytotypes, plants are grown out in the greenhouse and chromosome counts made on pollen mother cells. It is a laborious and time consuming process. The objective of this study was to determine whether electrophoretic techniques could be utilized to separate the cytotypes. Electrophoretic examination of seven isozyme systems from seed of 67 G. tabacina accessions revealed banding patterns that could be used to differentiate between diploid and tetraploid cytotypes in the species. Among the tetraploid accessions, the number of bands observed were always greater than the diploids. Some tetraploid banding patterns consisted of bands similar to the diploid tabacina and/or additional bands previously identified in other Glycine species. The patterns of isozyme multiplicity and variation in the tetraploid tabacinas suggests more than one mode of origin for the tetraploids.     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.