华北落叶松树干主要营养元素的空间分布

用标准地－标准木－分层分割法测定了华北落叶松（Ｌａｒｉｘ ｐｒｉｎｃｉｐｉｓ－ｒｕｐｐｒｅｃｈｔｉｉ Ｍａｙｒ）树干主要营养元素的分布规律,结果为：树干木质部水平方向Ｎ、Ｐ、Ｋ质量分数随年龄增加逐渐增大,Ｃａ、Ｍｇ的逐渐减少。树干木质部垂直方向Ｎ、Ｐ、Ｋ质量分数随圆盘高度增加而增加,Ｃａ、Ｍｇ变化较小。树皮Ｎ、Ｐ、Ｋ、Ｍｇ质量分数随圆盘高度的增加而增大,Ｃａ有减小的趋势,但梢部质量分数较高;树干主要营养元素的质量分数大小排序为：Ｋ〉Ｃａ〉Ｎ〉Ｍｇ〉Ｐ。不同个体不同组分质量分数之比分别为,皮／木 Ｎ：４．１～６．３,Ｐ：２．８～４．８,Ｋ：２．１～２．７,Ｃａ：２．３～４．１,Ｍｇ：２．１～３．１;皮／心,Ｎ：４．９～８．６,Ｐ：５．２～７．５,Ｋ：２．２～２．７,Ｃａ：２．６～３．８,Ｍｇ：２．０～３．２;边／     

成年龙眼园平衡施肥示范试验

示范试验结果表明,成年龙眼的平衡施肥对提高土壤肥力,保护树体适宜营养水平以及增加果实产量有明显作用,从而证实平衡施肥方案的可行性。作者推荐,闽南丘陵地成年龙眼园的年施肥方案：Ｎ２０￣２５ｋｇ;Ｎ：Ｐ２Ｏ５：Ｋ２Ｏ：ＣａＯ：ＭｇＯ＝１．０：０．５：￣０．６：１．０￣１．１：０．８：０．４。     

黄山药栽培试验：Ⅱ.几种栽培技术对出苗率,次生根茎生长量, …

对黄山药两年田间试验的结果表明,在根龄、方式、施肥组合和施肥期４个因素中,根龄是影响出苗率和产量的主要因素,与出苗率和产量为反向关系;施肥组合是生长量的主要因素,其中以施Ｎ５９．７、Ｐ１１９．７、Ｋ２９．７ｋｇ／ｈａ的生长最最高,施Ｎ２８．９、Ｐ８０．１、Ｋ８９．１ｋｇ／ｈａ的次之;栽培方式主要是影响薯蓣皂甙元呈,影响大小顺序为：育苗移载〉地膜覆盖〉露地栽培,施肥期只对生长量和产量有一定的影响,以     

鼎湖山南亚热带常绿阔叶林植物营养元素含量分配格局研究

在鼎湖山南亚热带常绿阔叶林中,植物叶片营养元素含量为Ｎ ０．９４６％－２．５３５％,Ｐ ０．０３０－０．１２７％,Ｋ ０．６１４％－１．８３３％,Ｃａ ０．４４２％－１．９９５％,Ｍｇ ０．０２４％－０．１８８％。叶片各营养养元素间相关性较差,仅Ｐ与Ｍｇ及Ｍｇ与Ｋ之间存在显著的线性相关。叶片Ｎ元素平均含量在各层中的序列为：乔木Ⅲ〉乔木Ⅱ〉乔木Ⅰ〉灌木〉藤本〉草本;其它营养元素浓度随层次分配的规律性     

福建和溪亚热带雨林凋落物营养元素动态

探讨了福建和溪亚热带雨林主要营养元素通过凋落物的归还动态．结果表明,该森林一年中凋落物不同组分各元素的含量具有波动性,加权平均含量为Ｎ＞Ｋ＞Ｃａ＞Ｍｇ＞Ｐ（落果Ｃａ＝Ｍｇ、落枝Ｃａ＞Ｋ）。通过凋落物归还Ｎ、Ｐ、Ｋ、Ｃａ、Ｍｇ元素的年库流量,分别为８７．４１、３．８２、４０．８０、２８．８１和１５．３２ｋｇｈｍ（－２）,灰分量为２８４．５７ｋｇｈｍ（－２）,其中以落叶形式居最大,分别各占总量的７３．４％、６８．１％、．７７．２％、７２．９％、７４．５％和７９．９％;各元素的年库流量与年凋落物量的月分布相一致,有明显的季节性．森林地表残留物Ｎ、Ｐ、Ｋ、Ｃａ、Ｍｇ元素的累积储量．分别为５４．８３、２．４５、９．６９、１７．０和９．２５ｋｇｈｍ（－２）．五种元素在林下地表的滞留时间,分别为Ｎ０．６１、Ｐ０．６１、Ｋ０．２３、Ｃａ０．５６和Ｍｇ０．５３年．     

武夷山甜槠林生态系统的养分平衡研究(英文)

本文通过比较大气降水的养分输入与由地表径流与地下渗流的养分输出,对武夷册甜槠林生态系统的养分平衡进行了研究。结果表明,在１９９３年４月至１９９４年４月期间,通过大气降水进入甜槠林的养分元素以Ｎ最高,为３４．２０７ｋｇ．ｍ＾２,其余依次为Ｃａ,Ｓ,Ｎａ,Ｋ和Ｍｇ,以Ｐ的输入最低,仅１．７７９ｋｇ．ｈｍ２;由地表径流和地下渗流的养分输出总量Ｎ,Ｐ,Ｋ,Ｃａ,Ｍｇ,Ｓ,Ｎａ分别为５．６８,１０１６,７．     

黑曲霉生产β-葡萄糖苷酶发酵条件的研究产

经多项式回归分析,研究了不同浓度Ｎ 源、Ｃ 源、无机盐等对酶产量的影响,确定出最佳培养基配方为：麸皮４ ．９ ％ ,（ＮＨ４）２ＳＯ４ ０ ．４ ％ ,ＫＨ２ＰＯ４ ０ ．２９ ％ ,ＣａＣｌ２ ０ ．０５ ％ ,ＭｇＳＯ４·７Ｈ２Ｏ０ ．０４ ％ ,ＦｅＳＯ４·７Ｈ２ Ｏ５ｍｇ·Ｌ－ １ ,ＺｎＣｌ２ １ ．４ｍｇ·Ｌ－ １ ,０ ．２ ％ 油酸钠．并对培养温度、时间、培养基初始ｐＨ、通气量、接种量、接种方式等培养条件进行优化,使黑曲霉生产β葡萄糖苷酶的产量由１７Ｕ·ｍｌ－ １ 增至２１ ．３Ｕ·ｍｌ－ １ ．     

西双版纳次生林火烧前后土壤养分变化的研究

研究了火烧对西双版纳热带次生林下土壤养分的影响。火烧后０～１０ｃｍ土层的ｐＨ、有机质、全Ｎ、Ｐ、Ｋ和有效Ｎ、Ｐ、Ｋ都显著提高,ｐＨ、有机质、全Ｎ、Ｋ和有效Ｎ、Ｋ达０．１％显著水平,有效Ｐ达１％水平,全Ｐ达５％水平。但１０～３０ｃｍ土层的上述各指标均无显著变化。火烧前后各土层的Ｃ／Ｎ比率变化均不显著。     

鼎湖山马尾松林营养元素的分布和生物循环特征

较系统地研究了鼎湖山马尾松林营养元素的分布和生物循环情况。马尾松林内各组分营养元素浓度总的规律为：针叶－细根－林下层植物－凋落物－树皮－树干;在树皮,树干和凋落物组分中各营养元素的排序为：Ｎ－Ｃａ－Ｋ－Ｍｇ－Ｐ,其它组分中则为：Ｎ－Ｋ－Ｃａ－Ｐ－Ｍｇ。马尾松林各营养元素的总贮量（ｋｇ／ｈｍ＾２）为：２２７８．５１（Ｎ＊）,２８０．０１（Ｐ）,５６７．９０（Ｋ）,４５６．８４（Ｃａ）,１４４．７６（     

一株根霉产脂肪酶发酵条件的研究

通过对筛选出的一株根梅ＲｈｉｚｏｐｕｓＹ－９２产旨肪肪酶发酵２基组成（Ｃ,Ｎ,无机盐）及工艺条件的探索,并经正交实验,得到较优培养基配方为：蛋白胨６％,豆饼粉４％,葡萄糖１％,ＭｇＳＯ４·７Ｈ２Ｏ０．１％,ＫＨ２ＰＯ４０．３％,起始ＰＨ８．０,在此条件下,发酵液酶活可达９９．１５ｕ／ｍｌ,是初始酶活的１７８％。     

Formulation of a liquid fertilizer for sorghum (Sorghum bicolor (L.) Moench) using vermicompost leachate

Leachate from vermicomposting contains large amounts of plant nutrients and can be used as liquid fertilizer, but normally diluted to avoid plant damage. The amount of nutrients applied is thus reduced so that an additional fertilizer is required. We investigated how dilution of vermicompost leachate combined with different concentrations of NPK triple 17 fertilizer, and polyoxyethylene tridecyl alcohol as dispersant and polyethylene nonylphenol as adherent to increase efficiency of fertilizer uptake, affected sorghum plant development. The vermicomposting leachate with pH 7.8 and electrolytic conductivity 2.6 dS m(-1), contained 834 mg K(+) l(-1), 247 mg NO(3)(-)l(-1) and 168 mg PO(4)(3-) l(-1), was free of pathogens and resulted in a 65 % germination index. Vermicompost leachate can be used as liquid fertilizer for the cultivation of sorghum without dilution and mixed with 140-170 g l(-1) of NPK triple 17 fertilizer and 2-3 ml(-1) of dispersant and 0-1 ml l(-1) adherent. It was found that vermicompost leachate stimulated plant development, but fertilization with NPK was required for maximum growth.     

Conversion of AFLP fragments tightly linked to SCMV resistance genes Scmv1 and Scmv2 into simple PCR-based markers

In a previous study, bulked segregant analysis with amplified fragment length polymorphisms (AFLPs) identified several markers closely linked to the sugarcane mosaic virus resistance genes Scmv1 on chromosome 6 and Scmv2 on chromosome 3. Six AFLP markers (E33M61-2, E33M52, E38M51, E82M57, E84M59 and E93M53) were located on chromosome 3 and two markers (E33M61-1 and E35M62-1) on chromosome 6. Our objective in the present study was to sequence the respective AFLP bands in order to convert these dominant markers into more simple and reliable polymerase chain reaction (PCR)-based sequence-tagged site markers. Six AFLP markers resulted either in complete identical sequences between the six inbreds investigated in this study or revealed single nucleotide polymorphisms within the inbred lines and were, therefore, not converted. One dominant AFLP marker (E35M62-1) was converted into an insertion/deletion (indel) marker and a second AFLP marker (E33M61-2) into a cleaved amplified polymorphic sequence marker. Mapping of both converted PCR-based markers confirmed their localization to the same chromosome region (E33M61-2 on chromosome 3; E35M62-1 on chromosome 6) as the original AFLP markers. Thus, these markers will be useful for marker-assisted selection and facilitate map-based cloning of SCMV resistance genes.     

不同施肥处理对木棉叶片光合特性和幼苗生长的影响

采用L25(53)正交实验设计设置不同氮、磷和钾肥施用量及配比﹝单株施用量分别为CO(NH2)22.0、4.0、6.0、8.0和10.0 g,Ca(H2PO4)24.0、6.0、8.0、10.0和12.0 g,KCl 0.6、1.2、1.8、2.4和3.0 g﹞,并设置不同复合肥施用量(单株施用量分别为10、20、30、40和50 g),比较了施肥后第1至第3个月木棉( Bombax ceiba Linn.)幼苗叶片光合指标﹝包括净光合速率( Pn)、水分利用效率( WUE)、PSⅡ最大光化学效率( Fv/Fm )和叶绿素相对含量( SPAD)﹞和幼苗生长指标(包括株高增长量、地径增长量和叶面积增长量)的变化。结果表明：总体来看,不同施肥处理组木棉幼苗叶片的Pn和WUE值升高,幼苗的株高增长量、地径增长量和叶面积增长量增加,但不同施肥处理对叶片Fv/Fm和SPAD值的影响较小;复合肥对叶片光合生理特性和幼苗生长的影响也较小。在施肥后的第1至第3个月,单株施用量氮肥4.0或6.0 g,磷肥4.0或8.0 g,钾肥1.2、1.8或3.0 g处理组幼苗叶片的Pn和WUE值显著高于对照(不施肥)和大多数处理组;单株施用量氮肥4.0或6.0 g、磷肥4.0~12.0 g、钾肥1.2~3.0 g处理组幼苗的株高增长量、地径增长量和叶面积增长量也均较高。综合分析结果显示：氮肥对木棉幼苗光合生理特性及生长的影响最大,钾肥次之,磷肥最小。综合考虑Pn值、WUE值、株高增长量、地径增长量和叶面积增长量,木棉苗期的适宜单株施肥量为N 1.84或2.76 g、P2 O50.72~2.16 g和K2 O 0.72~1.80 g。     

Some properties of a glycoprotein with calcium binding ability found in human biological fluids in macroglobulinaemia IgM.

An acidic glycoprotein with calcium-binding properties was isolated from the urine of patients with severe macroglobulinaemia IgM. The molecular weight of this protein determined by Sephadex gel filtration was found to be 62 000 +/- 2800 in Tris - HCl buffer and 21 000 +/- 1000 in 6 M guanidine - HCl. The amino acid and carbohydrate composition of the isolated glycoprotein is presented. Electrophoretic migration of this protein was observed to be greatly affected by calcium ions present in the buffer in a concentration of 10(-3) M. At least two sets of binding sites seem to participate in binding calcium. The values 2.2 - 10(6) M-1 for the apparent association constant and 4.4 - 10(-4) mol of Ca2+ bound per g of protein for high affinity bindings sites were estimated, on the basis of data from the equilibrium dialysis. The origin and possible biological role of this protein is discussed.     

长期施肥条件下西南黄壤旱地有效磷对磷盈亏的响应

以贵州黄壤肥力与肥效长期定位试验为平台,探究有效磷(Olsen-P)与土壤累积磷盈亏、磷肥用量的关系,确定西南黄壤旱地最佳磷肥施肥量,通过Mitscherlich方程模拟作物相对产量对土壤Olsen-P的响应关系,明确西南黄壤旱地的农学阈值.结果表明: 施用磷肥可显著提高土壤Olsen-P含量,不同施磷处理间提升幅度主要与磷肥施用量有关;不施磷处理土壤磷素一直处于亏缺状态,施磷处理土壤磷素有盈余,其中全量有机肥配施全量化肥处理(MNPK)作物吸磷量和磷素盈余量最高,同等施磷水平下,与单施化肥处理(NPK)相比,有机肥配施化肥处理(1/4 M +3/4 NPK、1/2 M +1/2 NPK)更能促进作物对磷素的吸收,提高磷素累积利用率.土壤累积磷盈亏与土壤Olsen-P增量呈显著直线相关关系(P<0.05),土壤中磷素每盈余100 kg·hm^-2,MNPK、1/4 M +3/4 NPK、1/2 M +1/2 NPK、NPK处理Olsen-P分别增加16.4、13.0、21.4、5.6 mg·kg^-1,有机肥与化肥配施能有效增加土壤Olsen-P含量.西南黄壤旱地Olsen-P的农学阈值为22.4 mg·kg^-1;土壤每年磷盈亏和Olsen-P含量与磷肥施用量呈极显著正相关关系(P<0.01),磷肥用量(纯P)为每年33.3 kg·hm^-2时,土壤磷盈亏呈持平状态,Olsen-P农学阈值对应的施肥量(纯P)为每年45.9 kg·hm^-2.西南黄壤旱地Olsen-P含量主要与施磷水平有关,当年施磷量为45.9 kg·hm^-2时可获得最佳的作物产量,磷肥利用率高;当年施磷量高于45.9 kg·hm^-2时,作物产量对磷肥用量无响应,大量磷素累积在土壤中,增加了磷素的环境流失风险.西南黄壤旱地长期施用有机肥处理单位累积磷盈余量提升土壤Olsen-P的速率大于单施化学磷肥处理.     

长期培肥黑土微生物量磷动态变化及影响因素

长期采用两种不同量有机肥(M2、M4)、化肥(NPK)方式培肥黑土,研究微生物量P在作物生长季动态变化．结果表明。施用有机肥微生物量P显著高于施用化肥(NPK)和不施肥(CK),微生物量P分别为M48．75～47．68mg·kg^-1,M2 3．02～37．16mg·kg^-1,NPK1．59～10．62mg·kg^-1,CK0．76～6．74mg·kg^-1之间,波动性较大．M4、M2处理微生物量P最大值出现在抽雄吐丝期,NPK、CK处理最大值出现在大喇叭口期;施肥数量和种类不同所引起的黑土微生物量P的差异并未因季节变化及玉米生育时期影响而明显改变．微生物量P的动态变化与绝大多数黑土生物、理化特性指标的动态变化没有显著的相关性;微生物量P与黑土生物、理化特性(除全钾外),植物氮、磷、钾含量有极显著的正相关关系,与黑土含水量呈显著正相关关系．     

Function of Semliki Forest virus E3 peptide in virus assembly: replacement of E3 with an artificial signal peptide abolishes spike heterodimerization and surface expression of E1.

The Semliki Forest virus spike glycoproteins E1 and p62 form a heterodimeric complex in the endoplasmic reticulum (ER) and are transported as such to the cell surface. In the mature virus particle, the heterodimeric association of E1 and E2 (the cleavage product of p62) is maintained, but as a more labile and acid-sensitive oligomer than the E1-p62 complex. The E3 peptide forms the N-terminal part of the p62 precursor and carries the signal for the translocation of p62 into the lumen of the ER. The question of whether E3 is also important in the formation and stabilization of the E1-p62 heterodimer has been addressed here with the aid of an E3 deletion mutant cDNA. In this construct, the entire E3 was replaced with a cleavable, artificial signal sequence which preserved the membrane topology of an authentic E2. The E3 deletion, when expressed via a recombinant vaccinia virus, abolished heterodimerization of the spike proteins. It also resulted in the complete retention of E1 in the ER and almost total inhibition of E2 transport to the plasma membrane. The oligomerization and transport defect of E1 expressed from the E3 deletion mutant could be complemented with a wild-type p62 provided from a separate coding unit in double infections. These results point to a central role of E3 in complex formation and transport of the viral structural components to the site of budding. In conjunction with earlier work (M. Lobigs and H. Garoff, J. Virol. 64:1233-1240, 1990; J. Wahlberg, W. A. M. Boere, and H. Garoff, J. Virol. 63:4991-4997, 1989), the data support a model of spike protein oligomerization control of Semliki Forest virus assembly and disassembly which may be mediated by the presence of E3 in the uncleaved p62 precursor and release of E3 after cleavage.     

Design, synthesis and antileishmanial in vitro activity of new series of chalcones-like compounds: a molecular hybridization approach

The chalcone-like series 1a-1g was efficiently synthesized from Morita-Baylis-Hillman reaction (52-74% yields). Compounds 1a-1g were designed by molecular hybridization based on the anti-inflammatory drug methyl salicylate (3) and the antileishmanial moiety of the Morita-Baylis-Hillman adducts 2a-2g. The 1a-1g compounds were much more actives than precursor series 2a-2g, for example, IC(50)=7.65 μM on Leishmania amazonensis and 10.14 μM on Leishmania chagasi (compound 1c) when compared to IC(50)=50.08 μM on L. amazonensis and 82.29 μM on L. chagasi (compound 2c). The IC(50) values of compound 3 (228.49 μM on L. amazonensis and 261.45 μM on L. chagasi) and acryloyl salicylate 4 (108.50 μM on L. amazonensis and 118.83 μM on L. chagasi) were determined here, by the first time, on Leishmania.     

Incubation of myosin with exogenous small components (g1, g2, or g3) in KSCN or LiCl and properties of g-exchanged myosins.

Myosin was incubated with a large excess of exogenous g1, g2 or g3 in 0.6 M KSCN (or in 4 M LiCl) for 1-2 h at 0-2 degrees C. KSCN (or LiCl) was then removed by dialysis. The composition of g-chains in the resulting myosin was analyzed by SDS-gel electrophoresis. When myosin was incubated with g1, the amount of g1 in myosin increased and the increment was nearly counterbalanced by a decrease in g3, whereas an opposite change was observed on incubation with g3. The amount of g2 was not changed by these treatments. The same ATPase activity as that of control myosin was observed in the presence of Ca2+ or EDTA with the myosins incubated with g1, g2, or g3, but the activity in the presence of Mg2+ was about one-half of the control. The Ca2+ sensitivity of actomyosin containing the treated myosins was slightly higher than that of actomyosin containing the control myosin. Spin-labeled g1 or spin-labeled g3 was incorporated into myosin, but the ESR spectra of two spin labels were not distinguishable. No information could be obtained from the ESR spectra by the addition of Ca2+, Mg2+, nucleotides or actin. Inhibition of ATPase activity was observed when SH groups g1 or g3 in myosin were chemically modified.     

Cadmium status of soils and plants from a long-term fertility experiment in southeast Norway

To determine whether the use of phosphate fertilizer resulted in measurable cadmium accumulation in soils and crops harvested, soil and plant samples were collected from some selected treatments of a seventy year-old fertilizer experiment at Møystad, southeast Norway. Soil samples after extraction with Aqua Regia or 1M NH₄NO₃ and plant samples after digestion were analyzed for Cd. Cadmium balance based on fertilizer and atmospheric inputs and crop removal and leaching losses was worked out. Neither the total nor the available (NH₄NO₃-extractable) Cd in the soil was significantly affected by Cd added through fertilizer, though a tendency of higher Cd in soils from the plots receiving higher amounts of fertilizer was seen. The same trend was also observed for the Cd concentration in plants. Annual Cd input rates (fertilizer and atmosphere) varied from 1.20 to 2.57 g Cd ha^-1 y^-1 and the Cd removal (crops and leaching) rates varied from 1.16 to 1.79 g Cd ha^-1 y^-1. The balance calculations based on the seventy years data indicated Cd accumulation in the soil was <1 g Cd ha^-1 y^-1, but that increasing the doses of either commercial fertilizer or farm yard manure would likely result in increased accumulation of the element. This may have a negative impact because the available soil Cd content would be increased at a faster rate, resulting in increased plant uptake. Although Cd tended to accumulate as a result of P fertilization, the rate of increase was slow. The annual increase in the total Cd content of fertilized plots varied from 0.04 to 0.12% indicating that it may take from 800 to 2000 years, depending upon the fertilizer input, to accumulate Cd equivalent to that currently present in the soil.