红三叶(Triolium pratense L.)浸提液对种子的化感效应

以普通红三叶种子为受体,采用培养皿滤纸法,初步研究了红三叶对6种不同浓度(0.025,0.05,0.075,0.10,0.15,0.20 g/mL)叶浸提液的化感响应.结果表明,红三叶的叶浸提液对其种子的发育具有不同程度的化感影响.红三叶不同浓度的叶浸提液对种子发芽势表现出"低促高抑"的浓度效应,而对发芽率表现出一定的抑制作用;红三叶不同浓度的叶浸提液对胚根长具有极强的抑制作用(p＜0.01),而对下胚轴长既具有抑制作用又有促进作用,且在一定浓度范围内表现出"低促高抑"的现象.     

不同品种马铃薯对谷子萌发的化感作用研究

为了研究不同品种、不同部位的马铃薯浸提液对后茬谷子的化感作用,筛选适宜谷子生长的前茬马铃薯品种,分别以7个马铃薯品种地上部分和地下部分为材料,制备不同浓度的马铃薯浸提液,并用浸提液处理谷子种子进行萌发实验。结果表明,所有浸提液处理均明显抑制谷子的发芽率,发芽势和发芽指数,抑制作用随着浸提液浓度的升高而增强。各种浸提液处理的根长和活力指数均小于对照值,随处理浓度增加,根长和活力指数呈下降趋势;低浓度浸提液处理促进谷子苗高、鲜重,而高浓度浸提液处理则起抑制作用。不同品种马铃薯的化感作用存在差异。马铃薯对后茬谷子存在化感作用,‘兴佳2号’、‘费乌瑞它’、‘中薯5号’对谷子的化感作用影响最小。     

匙叶翼首草种子浸提液对青稞种子化感作用的研究

以培养皿为小区,在实验室研究了农林复合系统中匙叶翼首草种子浸提液对甘青5号青稞种子萌发及幼苗生长的影响。结果表明：匙叶翼首草种子不同浸提时间的浸提液对青稞的化感作用效果不同,且出现了浸提液对青稞种子萌发及幼苗生长有短时间浸提液促进、长时间浸提液抑制的双重效应。且浸提48h的浸提液对青裸种子发芽抑制作用最大,浸提24h促进作用最大。匙叶翼首草种子不同浸提时间的浸提液对青稞的根系活力和过氧化氢酶活性的不同影响同样反映了不同程度的化感效应,同时彼此相互作用。     

几种植物对紫茎泽兰种子萌发抑制作用的研究

紫茎泽兰是我国外来入侵物种中危害最为严重的植物之一.为探讨贵州本地植物的化感作用与紫茎泽兰种子萌发之间的关系,采用培养皿滤纸法,研究了10种供体植物的叶片浸提液对紫茎泽兰种子萌发的影响.结果表明:10种供体植物的化感物质对紫茎泽兰种子萌发均存在化感作用,并且随着浓度的升高,化感作用逐步增强,紫茎泽兰种子发芽速度指数比发芽率更为敏感.其中,油茶、板栗、花椒、月月青4中植物的化感抑制效果最为显著,构树、苣荬菜、狗尾草的化感作用不明显.     

长叶车前浸提液对一年生黑麦草种子萌发特性的影响

以饲用长叶车前(Plantago lanceolata L.)为试验材料,研究其不同浓度的水浸提液对一年生黑麦草(Lolium multiflorum Lamk.)种子发芽的影响。结果表明:长叶车前水浸提液对一年生黑麦草种子的发芽率、发芽势、发芽指数及活力指数均有一定化感作用,0.1%、0.5%、1%的长叶车前浸提液处理种子与对照组发芽率、活力指数无显著差异,萌芽时间推迟;5%的长叶车前浸提液对一年生黑麦草种子萌发有显著的抑制作用,发芽率相比对照组较低。试验初步表明,长叶车前对一年生黑麦草存在高浓度抑制的化感作用。     

外来杂草波斯婆婆纳的化感作用研究

外来杂草波斯婆婆纳是我国区域性恶性杂草,主要在夏熟作物田中危害.通过其地上部分的水浸提液对小麦、油菜、早熟禾和高羊茅种子的萌发培养实验,研究波斯婆婆纳的化感效应.研究表明,波斯婆婆纳地上部分的水浸提液对4种受试植物种子萌发、根长和幼苗干重均有显著的抑制作用,浓度越高,抑制作用越强.在3个生测指标中,根长表现最敏感.在最高浓度下,高羊茅、早熟禾、小麦和油菜根长的化感效应指数分别为:-0.321 4、-0.491 6、-0.428 8和-0.856 6.不同植物对波斯婆婆纳化感作用的敏感程度也不同,早熟禾最敏感,其种子萌发、根长和幼苗干重在最高浓度下的化感效应指数分别为:-0.306 0、-0.491 6和-0.355 4.     

红景天果皮水提液对5种植物种子的化感作用

以狭叶红景天种子、榆荞种子、樱桃番茄种子、意大利耐抽薹生菜种子和新牛角椒种子为受试材料,研究了狭叶红景天果皮水提液对5种植物的化感作用.结果表明,不同浓度的狭叶红景天果皮水提液对5种植物种子的萌发、胚根及幼苗生长均表现出不同的化感作用影响.其中,对狭叶红景天种子萌发和胚根生长都表现为明显的抑制作用,并且随着处理浓度增高,抑制作用表现越强,但对幼苗的生长却表现出明显的促进生长作用,其中以0.02 g/mL的水浸液处理的狭叶红景天幼苗生长速度最快;对榆荞种子萌发和幼苗生长表现为低浓度促进生长和高浓度抑制生长的作用,而对胚根生长却表现抑制作用,并随着处理浓度的增高,抑制作用也越强;对樱桃番茄和意大利耐抽薹生菜种子的萌发和胚根生长也都表现为明显的抑制作用,对樱桃番茄幼苗的生长影响与榆荞的一致,对意大利耐抽薹生菜幼苗的生长影响与狭叶红景天植物一致;对新牛角椒种子萌发的影响与榆荞种子相同,对其胚根和幼苗生长影响都表现为促进作用,但也存在随着处理浓度增高,其产生的促进生长作用逐渐减弱的现象.     

茶梅对马蹄金等几种植物的他感效应初步研究

在室内用离体测定方法研究了荼梅不同器官水浸提液对马蹄金、黑麦草、高羊茅、翦股颖、早熟禾、白三叶、狗牙根、萝卜的他感效应.结果表明:在茶梅根、茎、叶、花浸提液相同处理时,8种植物种子萌发不同.经综合评价得出,8种植物萌发强弱依次为:萝卜>白三叶>黑麦草=高羊茅>马蹄金>翦股颖=早熟禾>狗牙根;且茶梅的根、茎、花浸提液对这8种植物种子的萌发具有较强的抑制作用,叶浸提液对8种植物种子萌发具有促进作用.     

迷人杜鹃凋落叶水浸提液对其自身种子萌发的影响

为明确迷人杜鹃凋落叶是否具有化感作用,采用培养皿法,研究了不同浓度迷人杜鹃水浸提液对其种子萌发、幼苗生长和生理生化指标的影响。结果表明:浸提液对迷人杜鹃种子发芽和幼苗生长的化感作用表现出"低促高抑"的浓度效应。在浓度为1 mg/m L时,促进了种子萌发、胚芽和胚轴长度的伸长,分别比对照增加了2.67%、17.71%和8.64%。在浓度为50 mg/m L时,发芽率降低77.88%,胚芽和胚轴长度降幅为65.82%、78.37%,抑制了植株生长。用浸提液浸种,在浓度为1 mg/m L时幼苗的根系活力和叶绿素含量提高,随着处理液浓度的提升,幼苗的根系活力和叶绿素含量降低,均可视为防碍生长的生理原因。     

退耕还林还草地区粮食生产现状及发展对策 ——以四川省炉霍县为例

本文简要地叙述了退耕后四川省炉霍县粮食生产中存在的问题及问题的严重性。并就此提出了解决问题的初浅建议。     

The model of information exchange and sharing for CAD/CAPP using STEP and XML schema

To solve the problem of product data exchange and sharing among heterogeneous systems, the key technologies, including manufacturing information sharing, file conversion from STEP AP203/AP214 to AP224 with the conversion ware of STEP neutral files, are discussed.Using STEP standard as information output of CAD systems, the AP203/AP214 file output from CAD systems is transformed to AP224 file with STEP neutral file, while CAPP systems obtained geometry and manufacturing process information of the parts with AP224 neutral files.By translating the STEP files into corresponding XML neutral files according to the transformation criterions constituted by STEP AP28, XML schema library is setup.Upon this, product data exchange and sharing of manufacturing information can be achieved.     

土壤资源信息系统（SRIS）的形成发展及应用

人口的剧增、土壤的退化和环境的恶化，是当前社会可持续发展所面临的严峻挑战。作为人类生存空间的土地资源的可持续利用成为政府和社会所关注的核心。由于土壤资源信息系统能够为用户提供准确、及时的土壤信息和相关信息，因此，利用GIS技术建立土壤资源信息系统是近年来普遍的趋势。概述了土壤资源信息系统(Soil Resource Information System, SRIS)的概念、形成及其发展过程。介绍了土壤资源信息系统在数字化制图、土地资源评价和环境保护、水土流失、“精作农业”各方面的应用，并对今后中国的土壤资源信息系统的发展提出了几点建议。     

枣智能专家系统数据库信息化推广应用

本文就枣智能专家系统数据库基本功能、性能指标及信息化推广应用等方面进行了分析叙述。     

Product knowledge documents retrieval based on hybrid semantic model

An approach based on hybrid semantic model (HSM) was proposed to the solve problem raised in the retrieval process of product knowledge documentation. It expands the traditional user query to a semantic set composed of user preference, context and query, while representing the knowledge documents and user interest with an ontology based fuzzy concept. The leaves in the ontology are selected as components of the document concept vector with the weight determined by the depth of the concept in the ontology graph, the quantity of the information contained, and occurrence in the document and the whole repository. Furthermore, ontology is used to express context and query, and to construct a user preference model. Different relevancy computation methods are adopted for different retrieval models. The semantic similarity between query or user preference and documentation is computed by cosine method. The semantic similarity of context is estimated by the concept distance in the concept hierarchy. Finally, the method is shown by experimentation to be more effective than the classic vector space method.     

A database management system for information retrieval and documentation of experiments for plant breeders

Summary An existing database system for seed collections has been augmented by programs providing plans for field experiments, record sheets and adhesive labels for seed packets. Information on accession names and parentage is picked up from the database. At the end of the season information on material seleeted in the trials is automatically added to the database.     

Product Lifecycle Information Model

The technology of product modeling is the basis of Advanced Manufacturing Technologies.Product model is the key to realize sharing information in developing product.Three kinds of product model are compared.Base on it,the concept of product lifecyele information model and its components,the architecture and the approach to modeling are presented.     

A Structure of Intelligent Information Retrieval Agent

When users try to get Information over the Internet, Information overload has become a serious problem.So we propose to use intelligent information retrieval IIR agents as a solution to this problem.Based on the analysis of the features of retrieval system, including intelligent search, navigation guide, auto-notification, personal information management, dynamic personalized Web pages, and tools for page reading-aide, we discuss the responsibility of each component of intelligent information retrieval agent and how to organize these components to perform various functions to settle above problem, referring to the modularization structure of agent. Intelligent agent is doable and efficacious to increase the efficiency of information retrieval and to lighten network jam by preliminary practice.