中国果树害虫一新记录种——一点木蛾的记述（鳞翅目：木蛾科）

本文首次记述我国为害荔技、龙眼叶片的一点木蛾Epimactis monodoxa Meyrick,是作者1983-1984年的研究成果。     

龙眼裳卷蛾微粒子虫的发现和对家蚕的影响

龙眼裳卷蛾ＣｅｒａｃｅｓｔｉｐａｔａｎａＷａｌｋｅｒ患微粒子病和该病原对家蚕有感染性、致病性在国内外尚未见到研究报道。国内除《中国森林昆虫》［１］中有龙眼裳卷蛾记述外,国际检索仅查到尼泊尔记录卷蛾总科中有一新亚种Ｃｅｒａｃｅｓｔｉｐａｔａｎａｎｅｐａ...     

龙眼种质资源亲缘关系的研究进展

龙眼(Dimocarpus longana Lour.)种质资源是龙眼育种研究的基础。种质资源的研究将为探讨龙眼起源、进化、分类、育种和资源保护与利用提供科学依据。从形态学、孢粉学、同工酶和分子生物学等方面综述了龙眼种质资源亲缘关系的研究进展,探讨了龙眼亲缘关系的研究现状、前景及尚待解决的问题,并分析了今后开展龙眼种质资源亲缘关系研究的方向与重点。     

中泰龙眼考察简报

龙眼与著名的荔枝隶属同科,均引自中国东南部。荔枝果实外观胜过暗黄褐色的龙眼,但龙眼的风味却受到许多人的喜爱。大约有百分之三十的中国人和泰国人,象喜爱荔枝一样喜欢龙眼鲜果,甚至还胜过荔枝。占世界龙眼产量的一半供应加工(罐藏或制干)。罐藏龙眼的风味优于罐藏荔枝。鉴于龙眼干具有滋补的功效,人们也常食用。 澳大利亚的龙眼商品性生产刚刚开始。以下提供的报道,系作者调查泰国、中国(包括台湾省)龙眼栽培区的资料。     

不同生态类型龙眼种质亲缘关系的ISSR分析

利用ISSR分子标记技术对不同生态类型的39份龙眼种质进行亲缘关系分析。研究结果表明,从100条ISSR引物中筛选出12条重复性好、条带清晰的引物,对39份龙眼种质基因组DNA进行扩增,得到152个位点,其中多态性位点117个,多态性比例为76.97%。供试龙眼种质间遗传相似系数变幅为0.57～0.92,说明ISSR标记能够揭示材料间较高的遗传多样性。UPGMA聚类结果表明,在0.65相似水平可以将39份龙眼种质分为3个类群,类群Ⅰ均为来自中国的南亚热带生态型龙眼;类群Ⅱ包括石硖和大乌圆2个南亚热带生态型龙眼品种,以及热带生态型龙眼四季蜜类型的品种和单株;类群Ⅲ包括来自越南和泰国的龙眼种质。不同生态类型对龙眼的亲缘关系影响不大,热带生态型和南亚热带生态型龙眼相互聚在一起,说明两种不同生态类型龙眼具有较多相同的遗传背景。本试验结果将有助于进一步开展龙眼的分类、遗传与进化研究。     

海南省东方市野生龙眼种群动态特征研究

野生龙眼是龙眼(Dimocarpus longan)的野生群体,是龙眼进行品种改良与创新的重要基因库。该研究对海南省东方市的野生龙眼资源进行实地调查,并从种群径级结构、静态生命表、存活曲线等方面进行了分析。结果表明:(1)东方市的野生龙眼所处群落的植被类型可以分为季雨林、热带雨林以及季雨林与热带雨林过渡带。(2)三种植被类型下野生龙眼种群大小依次为热带雨林过渡带季雨林。(3)三种植被类型下野生龙眼的存活曲线均趋于Deevey-Ⅱ型,种群各径级的死亡率基本接近。(4)数量变化动态指数表明季雨林、热带雨林区的野生龙眼种群为稳定型;过渡带的野生龙眼种群为增长型且趋于稳定。(5)时间序列预测分析表明,在未来的2、4个龄级后,季雨林下的野生龙眼种群从Ⅴ龄级之后的个体数呈现出增加的趋势,而热带雨林和过渡带是在Ⅳ级之后。从野生龙眼种群的整个发展阶段来看,目前三种植被类型下的野生龙眼幼年个体数相对丰富,种群维持有较充足的后备资源,中树、大树阶段的个体数能在现有基础上得到补充。继续保持现有野生龙眼种群分布的植株和生境斑块且采取有效保护措施,东方市的野生龙眼种群能有较好的恢复潜能。该研究的创新之处在于从不同植被类型下来分析东方市的种群动态结构,为处在不同植被类型的野生龙眼资源的种群特征提供了理论依据。     

华南地区龙眼寒害灾损风险评估

基于华南地区64个基本气象站1961—2012年逐日气象资料,采用公认的龙眼寒害灾害指标,结合农业气象灾害风险研究的方法与模拟技术,并考虑龙眼寒害灾损减产风险在不同生育期（花芽生理期、花芽形态分化期、休眠期）之间的差别,对1961—2012年华南地区龙眼不同发育时段的寒害灾损最大风险进行定量评估与分析.结果表明： 在花芽生理期,各地区龙眼受灾最严重的是轻度寒害,其次为重度寒害,最后为中度寒害;不同寒害致灾等级对各地龙眼造成的危害程度不同,在轻度寒害威胁下,龙眼受灾轻重次序为福建、广东和海南、广西,中度寒害威胁下,龙眼受灾轻重次序为海南、广东和广西、福建,重度寒害威胁下,龙眼受灾轻重次序为海南、广东和广西、福建.在花芽形态分化期,各地区龙眼受灾最严重的是轻度寒害,其次为重度寒害,最后为中度寒害;该时段内不同寒害致灾等级对各地龙眼造成的危害程度相似,龙眼受灾轻重次序均为海南、广东和广西、福建.在休眠期,各地区龙眼寒害受灾最严重的是轻度寒害,其次为重度寒害,最后为中度寒害;该时段内不同寒害致灾等级对各地龙眼造成的危害程度不完全相同,轻度和重度寒害威胁下,各地龙眼受灾轻重次序为海南、广东和广西、福建,中度寒害威胁下,海南和广西龙眼受灾最轻,其次为广东,福建受灾最严重.同一寒害致灾等级下,不同发育时段龙眼寒害灾损减产最大风险指数差异显著：轻度寒害威胁下,各地区龙眼在花芽生理期受到危害最重,其次为花芽形态分化期,休眠期危害最轻;中度和重度寒害威胁下,各地区龙眼在花芽生理期受到危害最重,其次为休眠期,花芽形态分化期危害最轻.     

龙眼叶片膜脂脂肪酸组分与龙眼耐寒性的关系

龙眼叶片膜脂不饱和脂肪酸含量和脂肪酸不饱和度与龙眼不同品种的耐寒性呈正相关;在年周期中,不饱和脂肪酸含量的变化与龙眼耐寒性的变化呈现平行关系;龙眼叶片膜脂脂肪酸组分含量反映着龙眼品种间耐寒性遗传上的差异,可作为耐寒性的鉴定指标。     

中国瘿螨科四新种记述（蜱螨亚纲：瘿螨总科）

本文记述瘿科４新种：生瘿螨亚科Ｃｅｃｉｄｏｐｈｙｉｎａｅ的竹生瘿螨Ｃｅｃｉｄｏｐｈｙｅｓ ｂａｍｂｕｓａｅ,ｓｐ．ｎｏｖ。瘿螨亚科Ｅｒｏｐｈｙｉｎａｅ的龙眼瘿螨Ｅｒｉｏｐｈｙｅｓ ｄｉｍｏｃａｒ ｐｉ,ｓｐ．ｎｏｖ。鲁迅瘤瘿螨Ａｅｒｉａ ｌｕｘｕｎｉ,ｓｐ。ｎｏｖ。和竹刺子瘿螨Ａｃｕｌｏｄｅｓ ｂａｍｂｕｓａｅ,ｓｐ．ｎｏｖ。模式标本保存在南京农业大学植物保护系。     

37份龙眼种质资源亲缘关系的ISSR分析

本研究利用ISSR技术对37份龙眼种质资源进行遗传多样性检测.研究结果表明,从100条ISSR引物中筛选出7条重复性好,条带清晰的引物对37份龙眼品种基因组DNA进行扩增,共扩增出54条带,其中43条具有多态性,比率为79.6%.不同龙眼品种间遗传相似系数变幅为0.69～0.97,平均达0.83,说明ISSR标记能够揭示材料间较高的遗传多样性.UPGMA聚类结果表明,ISSR标记能将37份龙眼品种完全区分开,并能将来源于中国、越南和泰国的37份龙眼品种分别聚类到中国、越南和泰国三大品种群,说明龙眼品种资源的亲缘关系与地理因素有关,三个国家的龙眼品种之间存在较大的遗传差异.本研究结果将为为龙眼品种资源的研究利用提供参考.     

壳聚糖酶的克隆表达与壳寡糖的制备分析

目的:克隆壳聚糖酶基因于大肠杆菌中实现高表达,制备壳寡糖。方法:以枯草芽孢杆菌总DNA为模板扩增壳聚糖酶基因(CSN),克隆至载体pET23a(+)上,转化菌株BL21(DE3)。重组子经0.5 mmol/L IPTG诱导后,SDS-PAGE和质谱检测与鉴定重组酶。酶纯化后水解壳聚糖,薄层色谱分析其水解产物。结果:质谱证明壳聚糖酶(31.5kDa)成功表达,表达量占菌体总蛋白的45%左右。纯化后重组酶浓度为900 mg/L,纯度95%、回收率85%,酶活力为10 000 U/mg。壳聚糖降解产物为壳二糖至壳四糖。结论:原核表达载体pET23a(+)-CSN构建正确,壳聚糖酶表达量与活性高,适用于水解壳聚糖制备壳寡糖。     

国内外蝗害治理技术现状与展望

本文首先概述了国内外蝗虫发生与为害的态势,总结了现阶段我国蝗虫发生与为害的主要特点:即农田飞蝗暴发频繁而且严重,草原土蝗的发生时常造成严重的经济损失,而且侵入城市干扰市民生活,我国与周边国家之间蝗虫过境迁移频繁,使用化学农药污染环境和农产品;分析了国内外蝗虫防治对策与技术的发展现状,重点介绍了应急防治和可持续治理对策、...     

Kinetics and thermodynamics of peroxidase- and laccase-catalyzed oxidation of N-substituted phenothiazines and phenoxazines

N -substituted phenothiazines (PTs) and phenoxazines (POs) catalyzed by fungal Coprinus cinereus peroxidase and Polyporus pinsitus laccase were investigated at pH 4–10. In the case of peroxidase, an apparent bimolecular rate constant (expressed as k _cat/K _m) varied from 1 ×10⁷M⁻¹s⁻¹to 2.6×10⁸M⁻¹s⁻¹ at pH 7.0. The constants for PO oxidation were higher in comparison to PT. pH dependence revealed two or three ionizable groups with pK _a values of 4.9–5.7 and 7.7–9.7 that significantly affected the activity of peroxidase. Single-turnover experiments showed that the limiting step of PT oxidation was reduction of compound II and second-order rate constants were obtained which were consistent with the constants at steady-state conditions. Laccase-catalyzed PT and PO oxidation rates were lower; apparent bimolecular rate constants varied from 1.8×10⁵M⁻¹s⁻¹ to 2.0×10⁷M⁻¹s⁻¹ at pH 5.3. PO constants were higher in comparison to PT, as was the case with peroxidase. The dependence of the apparent bimolecular constants of compound II or copper type 1 reduction, in the case of peroxidase or laccase, respectively, was analyzed in the framework of the Marcus outer-sphere electron-transfer theory. Peroxidase-catalyzed reactions with PT, as well as PO, fitted the same hyperbolic dependence with a maximal oxidation rate of 1.6×10⁸M⁻¹s⁻¹ and a reorganization energy of 0.30 eV. The respective parameters for laccase were 5.0×10⁷M⁻¹s⁻¹ and 0.29 eV. Received: 20 September 1999 / Accepted: 24 February 2000     

Coiled-coil nanomechanics and uncoiling and unfolding of the superhelix and alpha-helices of myosin

The nanomechanical properties of the coiled-coils of myosin are fundamentally important in understanding muscle assembly and contraction. Force spectra of single molecules of double-headed myosin, single-headed myosin, and coiled-coil tail fragments were acquired with an atomic force microscope and displayed characteristic triphasic force-distance responses to stretch: a rise phase (R) and a plateau phase (P) and an exponential phase (E). The R and P phases arise mainly from the stretching of the coiled-coils, with the hinge region being the main contributor to the rise phase at low force. Only the E phase was analyzable by the worm-like chain model of polymer elasticity. Restrained molecular mechanics simulations on an existing x-ray structure of scallop S2 yielded force spectra with either two or three phases, depending on the mode of stretch. It revealed that coiled-coil chains separate completely near the end of the P phase and the stretching of the unfolded chains gives rise to the E phase. Extensive conformational searching yielded a P phase force near 40 pN that agreed well with the experimental value. We suggest that the flexible and elastic S2 region, particularly the hinge region, may undergo force-induced unfolding and extend reversibly during actomyosin powerstroke.     

Synthesis of hapten and conjugates of coumestrol and development of immunoassay

3-O-Carboxymethylcoumestrol was prepared as the hapten for immunoassay by a partial alkylation of coumestrol with ethyl chloroacetate in acetone alkalized with potassium carbonate. 3-O-Ethoxycarbonylmethylcoumestrol was separated by column chromatography and finally was hydrolyzed with formic acid. 1H and 13C NMR data (APT, COSY, HMQC, and HMBC) revealed that the reaction was regioselective, as 3-O-ethoxycarboxymethylcoumestrol was the only monosubstituted derivative. The hapten was then conjugated to bovine serum albumin and used for immunization of rabbits. A radioimmunoassay (RIA) system was established based on the polyclonal antiserum and a 125I-labeled hapten-tyrosine methyl ester conjugate as the radioligand. Parameters of the RIA: sensitivity: 12 pg per tube, 50% intercept: 140 pg per tube, working range: 20-4000 pg per tube. The cross-reactivity of a panel isoflavonoid and lignan phytoestrogens was either negligible (e.g. formononetin 0.07%; biochanin A 0.06%) or not detectable at all. The major immunoreactive peak in HPLC fractions from an alfalfa extract had the same retention time as coumestrol standard and represented 94.8% of the signal. The remaining 5.2% of immunoreactivity was distributed between five minor peaks. We conclude that after the validation for particular matrices, the method will be a useful tool for analysis of coumestrol, especially in low volume and low concentration samples.     

白术同源四倍体的诱导和鉴定及其与二倍体过氧化物酶的比较

以白术（Atractylodes macrooephala Koidz.）二倍体组培苗为材料,对其四倍体诱导方法进行研究,共获得45个白术同源四倍体株系,为优良株系的选育提供了材料。此外,还分析比较了其中8个白术四倍体株系与二倍体的过氧化物酶同工酶（POD）的酶谱差异,发现四倍体各株系过氧化物酶同工酶谱比二倍体的均多了Rf0.310的谱带,且总过氧化物酶比活力也发生了很大改变,对探讨白术四倍体优良株系的生理生化机理具有一定的参考价值。     

Effect of soil salinity and water stresses on growth and content of nitrogen,chloride and phosphate of wheat and triticale

Summary Three wheats and one triticale were grown, up to flowering stage, in pots on calcareous soil adjusted to a range of salinities (S₁=3.5, S₂=6, S₃=8.5, and S₄=11 mmhos/cm, 20°C, soilpaste extract) by adding solution consisting of 3∶2∶1 of Na-, Ca- and Mg chlorides in chemical equivalent amounts. Moisture in the pots was kept at 100% (W₁), 40% (W₂) and 20% (W₃) of the available water. The vegetative growth, nitrogen and phosphate were affected by S and W treatments, chloride was affected only by S. The interaction S×W affected only dry weight. Varietal effect was observed between wheat as a group and triticale. Multiple quadratic regression equations of these properties on salinity and water revealed that the higher the available water the wider the range of tolerable salinity. Triticale was relatively more tolerant to water stress. Salinity increases Cl and decreases N, whereas water stress enhances N accumulation to a certain extent. However, in triticale at S₃ and S₄ the effect of water stress on N was overshadowed by the excessive salinity. This did not occur for the wheat (Florence). P trends were described. R² for P was low (0.7435–0.3603) which made interpretations rather difficult.     

放牧对牧草光合作用、呼吸作用和氮、碳吸收与转运的影响

研究放牧对草地植物生理活动的影响,对于揭示草地放牧演替的生理机制有重要意义.大量研究表明,家畜放牧对牧草光合作用、呼吸作用以及C和N吸收与转运的影响,可以分为生理伤害和生理恢复2个阶段.放牧通过改变草地冠层结构影响牧草光合作用,净光合作用速率短期内迅速下降,随着叶面积指数增加又逐渐上升,呼吸作用有相似的变化趋势.牧草放牧后再生长所需的C和N最初主要来自根系和留茬中的贮藏物质,此后随着牧草生长恢复逐渐由同化作用供给,C代谢与土壤N水平负相关.放牧后牧草生理活动变化与牧草遗传特性、种间竞争、家畜放牧特征、非生物环境等因素密切相关.