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1.
甜菜生长模型研究进展   总被引:3,自引:0,他引:3  
为探求适合中国区域化的甜菜生长模型,并加强自身模型的开发能力,本文对国内外甜菜生长模型的研究与发展综述可知,甜菜生长模型主要为3种:DSSAT-CERES-Beet模型、AquaCropBeet模型和APSIM模型,均可评价甜菜种植制度、管理措施、不同气候变化对产量的影响,监测土壤水分平衡包括潜在蒸散、实际土壤蒸发、植物蒸腾、根系吸水、径流、土壤渗漏以及不同土层的土壤水流等。这对国内甜菜生产潜力、农业管理和农业风险评估方面都有着重要的指导意义。  相似文献   

2.
介绍美国为农民服务的大豆专家咨询系统王育民(黑龙江省农业经济技术信息中心·哈尔滨150001)“专家系统”是一类包含着知识和推理的智能计算机程序,它能够以人类专家的水平完成特别困难的某一专业领域的任务。“农业专家系统”是把专家系统技术应用于农业领域的...  相似文献   

3.
作物生产系统模拟模型研究进展   总被引:4,自引:0,他引:4  
殷红 《杂粮作物》2000,20(3):30-33
阐述了作物生长模拟模型的国内外研究进展及各种模型特点,并讨论了作物生长模拟模型的应用。它的未来发展主要在:(1)更加深入、详细地模拟作物生产的各种过程;(2)与地理信息系统和计算机专家系统相结合,形成完善的作物生产计算机决策管理系统。  相似文献   

4.
根据中英农业部签署的中英农业科技谅解备忘录精神,英国布鲁姆斯巴恩农业试验站甜菜营养专家阿利森博士和植物病理专家阿谢尔博士于1993年9月30日~10月17日来华参观访问。在华期间,阿利森等两位专家向中国农业科学院甜菜研究所的科技人员介绍了英国的甜菜栽培、病虫害的防冶措施、甜菜营养(施肥)与甜菜块根品质的关系等,  相似文献   

5.
1991年10月4日~8日由农业部甜菜专家顾问组、中国农业科学院甜菜研究所、轻工业部甜菜糖业研究所、甘肃农业大学、甘肃省农业科学院有关专家组成的鉴定委员会对“甘肃河西灌区甜菜带田规范化种植技术”进行了鉴定。该课题由甘肃省农业厅经济作物处主持,张掖地区农业科学研究所等7个农业行政及技术推广部门共同参加了攻  相似文献   

6.
为给大麦生产提供栽培咨询、农情监测、生长状况比对、田间管理决策等技术服务,设计开发了一套大麦专家系统。本系统结合甘肃大麦生产实际和专家种植栽培技术及经验,采用Visual Basic研发了主界面,由VC++调用OpenGL图像库开发的大麦生长模型的模拟结果,嵌入了LabVIEW设计的大麦田间监视窗口界面,并利用Access软件开发了其数据库。试验结果表明,该系统界面友好,生产咨询栏目浏览便利,远程视频监控大麦田间状况失帧率范围为1.02%~1.11%,可实时模拟大麦可视化生长,并能与田间实际比较分析,误差值为0.15~0.25,能实现大麦田间管理和病虫害防治等推理决策,可信度高,可为抢抓农时的生产管理提供一种农业信息化技术新途径。  相似文献   

7.
不同规格垄作覆膜对甜菜产质量的影响   总被引:3,自引:0,他引:3  
甜菜地膜覆盖栽培,通过提高地温促进甜菜生长,显著提高了甜菜产量。为了探索覆膜甜菜更合理种植方式,我们于1997年进行了不同规格垄作覆膜对甜菜产质量影响试验,结果简报如下。1材料与方法试验设在中国科学院黑龙江农业现代化研究所“九五”国家科技攻关基点——...  相似文献   

8.
根据甜菜科研成果、专家经验和田间试验结果,采用微软access、C和VB语言,研制开发了甜菜高产高糖技术多媒体信息系统。该系统能够依据用户提供的信息,选择合理的推理机制,以甜菜专家的水平去解决甜菜生产中的技术问题,该系统操作方便,易于推广。  相似文献   

9.
在农业生产迫切要求科学种田的大好形势下,中国农业科学院甜菜研究所于1983年9月15日至16日在呼兰召开了甜菜除草剂应用技术研究成果鉴定会。会议邀请了中国农业科学院,黑龙江省农牧渔业厅植保站、经济作物处,省农业科学院植保所、经济作物研究所,省九三农管局科研所,克山县植保站,北京南郊农场畜牧分场等八个单位十七名专家和技术人员。会议推选中国农科院除草剂专家张泽溥研究员为鉴定委员会主任,黑龙江省农科院除草剂专家陈永康副研究员为副主任,省农牧渔业厅甜菜专家孙向德高级农艺师等十五名同志为委员。会议由鉴定委员会主任张泽溥同志主持。与会委员检查  相似文献   

10.
甜菜耐盐性形态学及生理生化特征研究进展   总被引:5,自引:0,他引:5  
土壤盐渍化是影响植物生长发育的重要因素,严重制约着我国农业的可持续发展。甜菜是耐盐性较强的作物,但严重盐渍化环境对其产质量影响较大,因此了解甜菜耐盐性机理并培育耐盐性较强甜菜品种对有效利用盐渍化土壤具有重要的意义。本文从盐胁迫对甜菜的形态学特征(种子萌发、幼苗生长、不同生长时期耐盐性)和生理生化特征(盐分离子积累与分布、渗透调节物质、离子选择性吸收、光合作用、抗氧化酶活性、植物激素)方面综述了甜菜耐盐性研究现状,并对目前存在的问题和未来可以进行的研究方向进行了探讨,旨在为进一步开展相关研究提供资料。  相似文献   

11.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

12.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

13.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

14.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

15.
Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.  相似文献   

16.
Plains rough fescue ( F estuca hallii) is an important forage grass species in western Canada. Seed for use in pastures and ecological restoration is in high demand but supply is limited because F. hallii is an erratic seed producer. Seed producers require an understanding of the factors that influence flowering and seed set in this species. The aim of this study was to assess the effect of irrigation and nitrogen fertilization on the flowering and growth of F. hallii in a native rough fescue prairie in Alberta, Canada. Irrigation had a strong positive effect on seedhead density, whereas fertilization had limited effects on growth and reproduction of F. hallii. These results demonstrate that under field conditions, available moisture is likely to be a key factor driving flowering and seed production in F. hallii.  相似文献   

17.
Pasture legumes are important components of both mixed farming rotations and permanent pastures in temperate climates. Breeding of two widely sown pasture legumes, subterranean clover (Trifolium subterraneum L.) and French serradella (Ornithopus sativus Brot.), is constrained by the long generation cycle, typically enabling only one generation per year. We hypothesized manipulation of culture medium and conditions would enable the development of a laboratory‐based protocol for in vitro reproduction in subterranean clover and French serradella. In vitro flowering and viable seed set was induced from both species. For subterranean clover, the most effective treatment was culturing on modified MS medium with 1 μm kinetin and 0·1 m sucrose under a 100 μmol m?2 s?1 light intensity and continuous photoperiod. For French serradella, culture on a hormone‐free B5 medium with 5 mm NH4Cl and 0·1 m sucrose under a 100 μmol m?2 s?1 light intensity and 20 h photoperiod was optimum. It is expected this technique will have application in accelerating generation turnover within breeding programs, for the study of factors influencing flowering in pasture legumes, and for the propagation of valuable yet enfeebled plants such as embryo‐rescued hybrids.  相似文献   

18.
Marine biomass diversity is a tremendous source of potential anticancer compounds. Several natural marine products have been described to restore tumor cell sensitivity to TNF-related apoptosis inducing ligand (TRAIL)-induced cell death. TRAIL is involved during tumor immune surveillance. Its selectivity for cancer cells has attracted much attention in oncology. This review aims at discussing the main mechanisms by which TRAIL signaling is regulated and presenting how marine bioactive compounds have been found, so far, to overcome TRAIL resistance in tumor cells.  相似文献   

19.
Evaluation of crop and forage yield stability is of increasing relevance in the context of current and recent environmental changes but, in contrast to other field crops, there are no published systematic analyses among forage crops in Europe. A study of stability performance was conducted with 13 Czech cultivars of lucerne at four locations over a 2‐year period with the following aims: (a) to evaluate yield stability of varieties across different environments and (b) to calculate measurable benefits of variety selection in relation to the specific environment. The cultivar Vlasta was identified as the highest yielding cultivar (annual yield 16.0 t DM/ha), whereas the lowest yielding cv. Magda, Tereza and Oslava averaged around 14.9 t DM/ha. Effect of genotype × environment interaction (G × E) was two times higher than for genotype alone. Additive main effects and the multiplicative interaction (AMMI) model showed that the highest yielding cultivars may not be stable across environments. This study demonstrated further that significant yield improvement could be detected, even among a relatively homogenous group of domestic cultivars, and this was driven mainly by site productivity: the improvement was +10% in low‐yielding sites, compared with +3% in high‐yielding sites. Results highlight that advanced agronomy should also consider stability parameters such as AMMI stability value or superiority measures for forage crops in response to the challenges associated with climate change.  相似文献   

20.
Summary Morphological and biochemical parameters that could be involved in resistance to late blight were studied in non-infected and in infected potato hybrids resulting from a cross betweenSolanum phureja, resistant toPhytophthora infestans, and a susceptibleSolanum tuberosum. Some morphological differences between resistant and susceptible hybrids, indicating a positive correlation between stem diameter and phloem thickness in the stem and resistance toP. infestans, were observed. The lignin content in the leaves of the resistant hybrid rose upon infection byP. infestans. In the leaves of the susceptible hybrid, a diminution of the lignin content could be observed upon infection byP. infestans. In the same context, peroxidasic activity raised upon infection byP. infestans in both resistant and susceptible hybrids. Further characterization of the hybrid clones based on the polymorphism of peroxidases was attempted using isoelectric focusing.  相似文献   

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