东北红豆杉配子形成与胚胎发育解剖观察1）

利用显微技术观察了东北红豆杉雌、雄配子形成和胚胎发育过程。结果表明：直生胚珠3月份恢复发育,5月中旬大孢子母细胞形成,下旬减数分裂,6月中、下旬雌配子体形成。3月中旬花粉母细胞减数分裂,经过1个月左右发育为成熟的单核花粉,4月底至5月初散粉。传粉后约2个月受精,受精后的原胚经历球形胚、卵形胚、柳叶形胚、棒槌形胚,进而发育成具有胚芽、胚根、胚轴和子叶的胚体。     

河南枸骨四新变种

描述了河南地区枸骨4新变种,即:①紫枝枸骨(Ilex cornuta Lindl.et Paxt.var.purpureoramula T.B.Zhao et J.Y.Chen,var.nov.)、②紫序枸骨(Ilex cornuta Lindl.et Paxt.var.trispinoso-duris T.B.Zhao,var.nov.)、③剌齿枸骨(Ilex cornuta Lindl.et Paxt.var.spina T.B.Zhao,var.nov.)和④多刺枸骨(Ilex cornuta Lindl.et Paxt.var.ultraspina J.Y.Chen et T.B.Zhao.Var.nov.)的形态特征和分布情况,并与原变种进行了比较。     

3种茜草科药用植物乙醇浸提液对萝卜种子 萌发及幼苗生长的化感作用

以3 种茜草科药用植物鸡屎藤也Paederia scandens (Lour.) Merr.页、剑叶耳草（Hedyotis caudatifolia Merr. et Metcalf）、玉叶金花（Mussaenda pubescens L.）为试材,采用乙醇提取的方法制备不同浓度的乙醇提液,通过测定其对受 体萝卜（Raphanus sativus L.）发芽率、根系活力、叶片游离脯氨酸和叶绿素含量的影响,比较化感作用强弱。结果表明院 不同供试植物乙醇提液其化感效应不同,且浓度高时,化感作用强;供试植物乙醇提液均显著降低了萝卜发芽率、发芽 速率指数,且剑叶耳草在这两个指标的抑制作用显著高于另二者;供试植物乙醇提液均极显著抑制萝卜胚根和胚芽的 生长,其中鸡屎藤乙醇提液抑制胚芽的作用最强,玉叶金花提液抑制胚根的作用最强;鸡屎藤比玉叶金花更显著地抑 制萝卜幼苗根系活力,然而剑叶耳草却显著地促进;供试植物乙醇提液显著降低萝卜幼苗叶绿素含量,显著提高叶片 脯氨酸含量;鸡屎藤乙醇提液使叶绿素含量减少69.47%耀87.00%,且叶绿素a辕叶绿素b 随处理浓度的增加而降低。     

紫外法测定细果角茴香中多糖的含量

运用苯酚-硫酸紫外分光光度法测定细果角茴香中多糖的含量。同时发现使用紫外分光光度法测定精密度好、重复性好、方法简便等特点。细果角茴香中多糖的含量为5.2%。紫外分光光度法是一种测定细果角茴香多糖含量的理想方法,亦可为其它类多糖质量分数的测定提供依据。     

正交试验法优化黄褐毛忍冬总皂苷的提取工艺

[目的]建立黄褐毛忍冬（Lonicera fulvotomentosa Hsu et S.C.Cheng）总皂苷的水提工艺。[方法]以黄褐毛忍冬总皂苷中有效成分α-常春藤皂苷的含量为考察指标,采用正交设计法考察加水量、煎煮时间、煎煮次数及浸泡时间4个因素对黄褐毛忍冬总皂苷提取工艺的影响,同时采用高效液相法测定α-常春藤皂苷的含量。[结果]加水量、煎煮次数、煎煮时间、浸泡时间对α-常春藤皂苷含量的影响程度不同,各因素影响程度的大小为：煎煮次数〉加水量〉浸泡时间〉煎煮时间,即煎煮次数对煎煮条件影响最大,为最重要的因素,其次为加水量、浸泡时间、煎煮时间。最优方案为：黄褐毛忍冬药材不用浸泡,加10倍量水煎煮3次,每次1.0h。方差分析结果表明,加水量和煎煮次数对α-常春藤皂苷含量的影响具有显著意义（PA=0.034〈0.05,PB=0.020〈0.05）,而煎煮时间、浸泡时间对水α-常春藤皂苷含量无显著影响（PC=0.500〉0.05,PD=0.264〉0.05）,对测定结果影响小,这与直观分析结果相吻合。[结论]优选提取工艺简单、稳定、可行。     

Overcoming the Stressful Effect of Low pH on Soybean Root Hair Curling using Lipochitooligosacharides

Abstract

Signal molecules are among the major factors required for the legume–bacteria symbiosis. The excretion of signal molecules by plants stimulates the bacterial Nod genes resulting in the production of lipochitooligosacharides (LCOs). LCOs cause root hair deformation (RHD) and induction of nodule cells division, leading to the formation of nodules. The chemical structure of LCOs determines their biochemical activities; for example, removal of the sulfate group can significantly reduce the morphogenic activities of LCOs. Stressful conditions interrupt the excretion of signal molecules by the legumes' roots and consequently the inhibition of LCO production by the bacteria. This research has studied the effect of different concentrations of LCOs on RHD of two soybean [Glycine max (L.) Merr] cultivars, AC Bravour and Maple Glen, under acidity stress. In the first experiment, two different concentrations of LCO (10^?7 and 10^?6M) and in the second experiment, three different concentrations of LCO (10^?7, 10^?6, and 10^?5M) were added to the soybean roots subjected to the pH levels of 4, 5, 6, and 7 for 24 h. By microscopy observation, the ratios of RHD were determined. Addition of LCOs resulted in RHD in both cultivars. Maple Glen roots responded similarly to different concentrations of LCO, whereas roots of AC Bravour responded differently. The concentration of 10^?5M LCO could inhibit the stressful effect of pH 4 on RHD compared with pH 7 in both cultivars. The significant interaction between LCO and pH suggests that the effect of LCO on RHD may be more significant under higher levels of acidity.     

超声波法提取川楝黄酮的试验研究

以川楝子为原料,采用超声波法提取其中的黄酮类化合物,通过正交实验研究其最佳的提取工艺。研究结果表明,超声波法提取川楝子黄酮的最佳工艺为乙醇浓度50%、液料比1:40、超声波提取时间40min、温度80℃,黄酮得率为0.561%,明显高于相同条件下传统水浴提取法的得率0.294%,和在相同乙醇浓度、料液比、提取温度条件下微波法的得率0.278%,研究结果为川楝子的综合开发利用提供了理论依据。     

金叶含笑的育苗及栽培管理技术

金叶含笑树干挺拔，树形丰满，枝条开张，是良好的园林风景树和绿艺树，既可作为城市道路绿化，也可作为营造园林景观配置之用，值得大力推广。文章介绍了金叶含笑育苗栽培技术，包括形态特征，生态习性，播种育苗、管理及病虫害防治等。     

Interaction of bovine immunoglobulin gamma 2 (IgG2) with staphylococcal protein A: evidence for IgG2a and IgG2b sub-subclasses in the bovine

The reactivity of bovine IgG with protein A is confusing with respect to which of the bovine IgG class and subclasses are reactive. We have, therefore, re-examined the interaction of bovine immunoglobulins with protein A. The results presented in this paper indicated that at pH 8.0 protein A binds only immunoglobulin of the IgG2 subclass. The bound IgG2 can be readily recovered from an immobilized protein A column at pH 5.0. Furthermore, the antigenic IgG2 eluted demonstrated two charged species which could readily be separated by ion-exchange chromatography. These results indicate that IgG2 in the bovine exists in two sub-subclasses, IgG2a and IgG2b. The two sub-subclasses of IgG2 could be rapidly isolated with a good yield in two-steps namely protein A affinity chromatography followed by ion exchange chromatography.     

Effect of Inoculant Rate on Nodulation and Various Agronomic Traits of Soybean

In a soil lacking indigenous Bradyrhizobium japonicum , soybean ( Glycine max [L.] Merr.) nodulation depends upon the number of rhizobia applied with the inoculum. This field study reports the effect of different rates of applied rhizobia on nodulation, dry matter and nitrogen content in soybean in a Mediterranean soil lacking B. japonicum.
Treatments included six rates of B. japonicum , ranging from 2.5 × 10⁴ to 6.075 × 10⁶ rhizobia cells per seed applied to the seed as peat inoculant at planting, 100 kg N ha⁻¹ and an uninoculated control. The experiment was conducted in an Entisol soil. Regression analysis showed linear relationship between the rate of applied rhizobia and the number of the nodules per plant or the dry weight per nodule. In early stages of development (32 and 68 days after planting) plant dry weight was not affected by inoculation rate. At harvest a rate of 7.5 × 10⁴ rhizobia cells per seed was necessary for maximum total and stover dry weight. A higher rate, 6.75 × 10⁵ rhizobia cells per seed, was required to obtain maximum grain yield, total N content in plant tops and grain N content. Grain percentage N was increased up to 2.025 × 10⁶ rhizobia cells per seed. Nitrogen application increased grain yield, total N content and grain N content at the same level as the lower inoculation rate.