天津地区洼淀蝗区的飞蝗发生特点

解放以来,对天津地区洼淀蝗区的飞蝗发生特点,进行了长期调查,兹总结如下。 洼淀蝗区的概况(图1) (一)形成 洼淀蝗区是由地理、自然、气候、水文、植被、飞蝗及其他生物等长期以来相互适应的结     

河北夏蝗大发生与气象条件的关系

利用合成分析和秩相关系数2种方法,分析了河北2种生态类型蝗区中夏蝗LocustamigratoriaL.发生程度与气象条件的关系,以确定影响夏蝗大发生的关键气象因子。结果表明:2个类型蝗区大发生年以前一年5月至当年夏蝗出土以前的气温偏高、降水偏少为主;前一年6月下旬、7月上旬、8月上旬、8月中旬气温、6月上旬降水、当年3月下旬降水、4月下旬气温为沿海蝗区关键影响因子,前一年7月上旬和8月下旬气温、5月中旬降水及当年2月中、下旬气温、4月下旬和5月上旬气温为洼淀蝗区的关键影响因子。     

河北省南大港农场2002年夏蝗发生特点及原因浅析

进入 90年代以来 ,南大港蝗区东亚飞蝗Locustamigratoriamanilensis(Meyen)大发生 6次 ,2 0 0 1年夏秋蝗发生面积达 2 6万hm2 ,5龄蝗蝻最高密度为 1 0 0 0 0头 m2 。 2 0 0 2年形势更为严峻 ,仅夏蝗发生面积超过 2万hm2 ;分别造成 1 3 0 0hm2 和 2 70 0hm2 的芦苇被吃成光杆和被啃食的严重破叶。出土时间早、孵化时间长、龄期悬殊大是今年夏蝗发生的主要特点。主要原因是去年越冬卵块基数大 ,其次是受气候条件和农业环境的影响     

白洋淀蝗虫分布调查及其防治

1998～ 2 0 0 2年对白洋淀蝗区的蝗虫种类、分布、优势种群及蝗区水文、植被、土壤、天敌等进行了调查研究。调查表明 ,白洋淀蝗区有蝗总科昆虫 3 0种 ,隶属 6总科、2 2属 ,分布于白洋淀淀内湖泊蝗区、淀边内涝蝗区和淀外河泛蝗区 ;明确以东亚飞蝗Locustamigratoriamanilensis (Meyen)为主的 5个蝗虫优势种群及生活史 ,并根据不同蝗区类型 ,提出了蝗区治理区划、生态治理技术、应急化学防治等 3项防治技术和“两改一加强”防治手段     

河北省黄骅市三个重点蝗区两个时段土壤湿度的遥感提取

蝗灾是人类历史上重要的自然灾害之一，影响蝗灾爆发的因素很多，其中土壤湿度是重要的影响因素之一。以位于河北省黄骅市境内的3个重点蝗区——黄灶、杨官庄和藤南大洼为监测样区，利用高时间分辨率MODIS遥感影像数据，分别提取2002年(东亚飞蝗大发生年)秋蝗产卵期到夏蝗孵化期间的土壤湿度信息以及2004年(东亚飞蝗轻为害年)相同时段的土壤湿度信息，发现蝗灾大爆发年份的土壤湿度明显低于轻发生年份，在秋蝗的产卵期(9—10月)和夏蝗的孵化期(3—5月)差异尤为明显。     

河北省黄骅市三个重点蝗区两个时段土壤湿度的遥感提取

蝗灾是人类历史上重要的自然灾害之一,影响蝗灾爆发的因素很多,其中土壤湿度是重要的影响因素之一。以位于河北省黄骅市境内的3个重点蝗区——黄灶、杨官庄和藤南大洼为监测样区,利用高时间分辨率MODIS遥感影像数据,分别提取2002年(东亚飞蝗大发生年)秋蝗产卵期到夏蝗孵化期间的土壤湿度信息以及2004年(东亚飞蝗轻为害年)相同时段的土壤湿度信息,发现蝗灾大爆发年份的土壤湿度明显低于轻发生年份,在秋蝗的产卵期(9—10月)和夏蝗的孵化期(3—5月)差异尤为明显。     

沿淮蝗区水涝与飞蝗发生关系的初步调查及其在防治措施上的探讨

本文根据沿淮蝗区的历史情况、饲养观察、气象、水文等资料,加以整理与分析: 1.从产蝗基地形成的过程中,阐明飞蝗生态特性与水涝之间的联系,从而了解飞蝗消长规律是由这种联系内在矛盾和统一的更替影响的结果。 2.雨水对飞蝗发生有一定的控制作用,故雨量的多寡与雨量的分布具有飞蝗生态上的重大意义: (1)淮河流域雨量适中,全年雨量集中在7、8两月,雨期短,湖滩洼地暴露时间长,故 宜飞蝗生长繁殖,同时该蝗区雨量较多,加之年雨量变幅大(年雨量相对变率超出25％以上,接近30％),及淮河水流平缓吐洩困难等原因,故而有大水涝灾发生,对飞蝗繁殖有很大的限制。 (2)雨期推移与蝗虫的盛衰是有直接的联系:(i)全年雨量表现在两个高峯以上,即夏秋蝗蝗卵发育及孵化时间多雨,蝗卵的死亡淘汰高,蝗情在雨量控制下基本不能猖撅成灾。(ii)雨期提前即夏蝗在卵的发育后期和孵化期遭高雨量的影响淘汰,以及秋蝗受高水位的影响不得大量发生。(iii)雨期移至7月份正值夏蝗成虫活动和秋蝗孵化的交错时期,对蝗情影响程度须视雨期前后、雨量大小而定。(iv)雨期后移至8月,即夏季季尾雨量一般较少,水情不大,而利于夏蝗发生,对秋蝗影响也少,往往在这种情况下,造成蝗虫大量的发生。 (3)雨水对蝗卵发育后期及孵化期有严重的影响,不仅是引起     

1995年白洋淀东亚飞蝗大发生原因及防治策略

白洋淀是华北地区最大的淡水湖,是历史老蝗区,河北省东亚飞蝗Locustamigratoriamanilensis（Meyen）重点蝗区之一。1995年夏蝗呈特大发生,形成大面积高密度群居型蝗蝻,是20年来极为罕见的。其发生特点为蝗蝻出土集中,非农田蝗区密度高于农田蝗区,高密度群居型蝗螨均发生在淀边苇田蝗区。发生面积1．2万hm2,防治1．l万hm2,其中发生10头／m2以上的有0.7万hm2,100头／m2以上的0.l万hm2。现将分析的特大发生原因及防治策略报道如下。1大发生原因1．1大发生的蝗虫基数：据调查,1994年秋残蝗面积为1．2万hm2,比中等发生年多0．3万hm2…     

白洋淀东亚飞蝗持续大发生浅析

进入 90年代以来 ,白洋淀蝗区东亚飞蝗Locustamigratoriamanilensis(Meyen)持续大发生 4次 ,是50年来十分罕见的。究其原因 ,主要受白洋淀水位变化的影响 ,其中 8月水位的高低直接影响翌年夏蝗发生程度 ,其次是生态环境和气候条件等因素的影响。     

蝗卵的研究,Ⅰ.亚洲飞蝗蝗卵孵育期中胚胎形态变化的观察及野外蝗卵胚胎发育期的调查

一.引言 亚洲飞蝗(Locusta migratoria manilensis Meyen)(以下简称飞蝗)在我国沿海诸省每年一般发生两代。根据在洪泽湖与微山湖蝗区观察的结果,夏蝗在6月下旬和7月上旬产卵,至同年7月中、下旬孵化;秋蝗在9月上、中旬产卵,到次年6月上旬孵化。越冬蝗卵在土中停留8个月左右的时间,这使它们有充分的机会去领受当地环境因素如寒冷、干,湿、天敌等的作用,从而左右次年飞蝗发生时间     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

The effects of glutamine of the maintenance of embryogenic cultures of Cryptomeria japonica

Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l⁻¹ glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l⁻¹) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.     

Specificity of action of piperidylcholine derivatives as substrates of cholinesterases of various origin

The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

医疗机构合理用药评价模型的构建研究

目的 针对医疗机构的合理用药水平进行评价研究。方法 根据医疗机构合理用药的具体要求,构建医疗机构合理用药评价指标体系,采用基于模糊群决策的方法和多指标评价分析法构建医疗机构合理用药评价模型。结果 构建了基于模糊群决策的医疗机构合理用药评价模型,并通过实例分析证明了评价模型的可行性。结论 建立的基于模糊群决策的医疗机构合理用药评价模型能够对医疗机构的合理用药水平进行科学评价,为提高医疗机构合理用药水平奠定基础。