提高高羊茅愈伤组织诱导率的研究

用不同浓度的2，4-D，不同种类的培养基，对3个不同品种高羊茅成熟种子进行愈伤组织诱导，结果表明：这3个高羊茅品种对2，4-D均不敏感，诱导浓度需高于一般禾本科诱导浓度2mg／L；3种不同培养基MS、CC、NB中，CC培养基为最适培养基。此外，本实验还对外植体处理方法进行了改进，将胚乳切除后，愈伤组织诱导率大大提高，愈伤组织质量也有很大程度改善。     

在夏季应用氯前列烯醇诱导流产山羊发情的研究

选择2～5岁繁殖正常、体况中等的黄淮山羊空怀母羊10只为对照组,妊娠60 d母羊4只注射己烯雌酚流产后3～5 d为试验组,应用氯前列烯醇诱导发情。结果表明,试验组羊雌二醇、孕酮1～9d均呈上升趋势;9d雌二醇与1d比较呈显著性差异(P<0.05);而4d孕酮高于1d和14d,呈显著性差异(P<0.05)。在整个试验期,试验组孕酮含量均低于对照组(P>0.05)。PGc二次处理试验组96 h内发情率50％,均为异常发情。综合分析认为,夏季母羊流产后12～14d卵巢出现产后首次卵泡波,流产早期不适合诱导发情。     

外源激素对间情期毕格犬发情及妊娠的影响

给６只间情期雌性毕格犬注射外源激素雌酮（Ｅ１）、孕马血清促性腺激素（ＰＭＳＧ）、人绒毛膜促性腺激素（ｈＣＧ）和雌二醇（Ｅ２），结果有５只犬发情，３只受孕，产仔１４只。发情前期、发情期与自然发情犬无明显差别。发情犬血浆ＬＨ高峰出现在阴门见有血样分泌物后（１１．６±１．６）ｄ；在ＬＨ高峰期血浆孕酮（Ｐ４）明显升高，其后１２ｄ，Ｐ４含量达峰值；８０％阴道上皮细胞角化后（６．４０±０．６８）ｄ出现ＬＨ峰     

A INTERESTING SEQUENCE OF REAL NUMBER AND THEIR PROPERTIES

The yandongkai' s 2-stories "v' shape sequence of natural number is generalized to 2-stories and n-stories "v" shape sequence of real number,and some very interesting properties are given.x     

Applicationg of Ultraviolet Spectrophometry to Determination of Total Nitrogen in the Three Gorges Reservior

The eutrophication of water body will destroy the balance of ecological environment.To determine the total nitrogen content in water body exactly,is one of the most important evaluating indicators that whether the water body has been polluted by eutrophication or not.After the foundation of the Three Gorges Reservoir,current velocity lowers and it may result in the eutrophication of water body.In terms of the Lambert-Beer Law,the authors adopt potassium sulpersulphate oxidation-ultraviolet spectrophotometry to determine the total nitrogen content in the Three Gorges Reservoir.By analyzing a variety of possible factors,they bring forward a method to determine the total nitrogen which can be used in lab and also have high performance.With this improved method,the authors determine the factual water samples of the Three Gorges Reservoir in the main urban area of Chongqing,and the result is that the total nitrogen content is(0.6~1.0) mg/L,less than the limiting value(2.0 mg/L) in national standard.So the water body of the Three Gorges Reservoir still eutrophication does not take place.So eutrophication does not take place in water body of the Three(Gorges) Reservior.     

白术叶片再生植株和丛生芽快繁的研究

白术是菊科的一种重要药用植物。为满足白术的药用需求，扩大其资源供应，避免传统开荒育苗种植模式对生态环境的破坏，为白术的大规模工厂化育苗及获取药用次生代谢产物提供有效的途径和方法，笔者以白术叶片为外植体经愈伤组织再生植株和丛生芽增殖两种方式建立了白术无菌苗的快速繁殖技术，分析了不同植物激素种类和浓度对白术叶片再生植株及丛生芽增殖的影响，研究了温度和光照条件对白术叶片愈伤组织褐变的影响。研究结果显示在培养基MS+ 6-BA1 mg/L+NAA0.2 mg/L上白术丛生芽增殖倍数最高，可达4.45倍；以白术的叶片愈伤组织诱导及再生植株的最佳培养基为MS +KT 1mg/L+NAA0.2 mg/L，愈伤组织诱导率可达96.7%；芽分化率为90%。不同的细胞分裂素种类与浓度处理差异显著，在白术叶片的愈伤组织诱导中，KT的效果要优于6-BA，但在丛生芽增殖中则表现出高浓度的6-BA要优于KT。白术叶片愈伤组织继代培养中褐变程度与温度、光照条件有关，1000 lx光照强度，20±0.5℃的温度条件下继代培养能有效控制褐变。     

Analysis of the Damage Electric Field Strengths for Several Ultraviolet Thin Film Materials

The laser induce damage threshold electric field instensity strengths of different materials used in the ultraviolet region, have been calculated by the model of multiphoton absorption ionization, avalanche model and a combination of the two. Avalanche model can not be used in the ultraviolet region, the result of the combination model can be used as reference. The authors analyze the relations between the laser induce damage electric field strengths to optical thin film and laser frequency, pulse duration. The relations between materials band gap and damage threshold electric field strengths is analyzed.     

光敏感核不育水稻育性诱导和转换过程中叶片内碳水化合物的变化

本文以光敏感核不育水稻农垦58-s 和常规水稻农垦58为材料,从第一次枝梗原基分化后期至花粉母细胞形成期用不同光周期(SD 和 LD)进行育性诱导处理,半微量的二硝基水扬酸法定糖结果表明:1.从第一次枝梗原基分化至雌雄蕊形成期,农垦58(SD~(**)或 LD~(***))的淀粉含量逐渐增加,蔗糖和还原糖含量经过一个相对稳定的阶段(Ⅱ—Ⅲ)后,迅速增加,至雌雄蕊形成期时,淀粉、蔗糖和还原糖含量达到高峰,随后逐渐下降。2.从第一次枝梗原基分化至雌雄蕊形成期,农垦58-s(SD 或 LD)的淀粉、蔗糖和还原糖含量的变化规律与农垦58一致。但是,在雌雄蕊形成期之后,农垦58-sSD~(****)的蔗糖含量下降,淀粉和还原糖含量缓慢增加,而农垦58-sLD~(*****)的淀粉、蔗糖和还原糖含量均明显增加。推测长日照可能通过某些代谢环节影响了农垦58-s 叶片内碳水化合物向雄蕊的运输。营养缺乏是造成小饱子败育的重要原因之一。     

Chemical induction of apomictic seed formation in maize

Summary Silks of 18 maize (Zea may L.) F₁ hybrids were treated with different combinations of 9 growth regulators, colchicine, and dimethyl sulfoxide (DMSO) for the purpose to induce apomixis (agamospermy) in 1988 and 1989. Hybrid K301 × K303 gave the highest (0.36%) average frequency of seed induction among the hybrids. The most effective treatments were DMSO, gibberellic acid plus 6-benzyl aminopurine (6-BA), and DMSO plus methanesulfonic acid. Individually, the highest frequency of seed induction was 1.4% for hybrid K731×K306 when treated with -naphthalene acetic acid (NAA)-zeatin mixture. The frequency of seed induction seemed to depend partially on the interaction between chemicals and hybrids. Cytological observation of root-tip cells indicated that the majority of the seeds obtained were diploid, some were mixoploid, and a few were haploid. Diploid plants from induced seeds from the same parent were morphologically uniform and resembled the parent. Variations in plant and ear heights were comparable to those of the hybrid parent. Cytological and morphological investigations suggested that the chemically induced seeds originated mainly from somatic tissue but occasionally came from reduced cells in the embryo sac, leading to haploids. The results showed that chemical induction of adventitious embryony in maize hybrids is possible, but the more effective chemicals, their concentrations, and ways of application for increasing the frequency of seed induction need to be explored for practical use.