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1.
灰色灾变理论在宁南山区干旱气候预测中的应用   总被引：15，自引：2，他引：15  
在分析宁南山区干旱气候特征及其对农业生产影响的基础上 ,借助灰色灾变理论分别建立了春旱、夏旱、秋旱、春夏连旱、夏秋连旱、全年旱等六种干旱类型的 GM( 1 ,1 )预测模型 ,并对 2 0 0 0～ 2 0 2 0年的干旱气候做出预测。经对 2 0 0 0年和 2 0 0 1年预测结果验证 ,吻合性良好。此外 ,提出了宁南山区抗旱防旱的综合农业措施。研究结果可对广大旱区抗旱减灾 ,促进农业生产发展提供科学指导。  相似文献   

2.
宁夏南部山区生态环境建设与科技扶贫战略研究   总被引：15，自引：2，他引：13  
干旱、低产、人口膨胀，是造成宁南山区生态环境恶化和经济发展缓慢的重要原因。在基本解决温饱的基础上，抓住西部大开发历史机遇，以生态环境建设为切入点，以发展集水型庭园经济为突破口，以提高劳动者素质和致富技能为本，依靠科技进步，推进农业结构调整，合理配置水土资源和劳动力资源，形成具有区域特色和市场竞争力的民族经济体系与可持续发展模式，应是宁南山区的战略目标。分别论述了3个类型区建设与发展的技术关键，为宁南山区生态环境建设与科技扶贫开发提供决策依据。  相似文献   

3.
论宁南旱区农业技术   总被引：5，自引：5，他引：5  
基于旱区范围趋于扩大、干旱程度趋于严重等的干旱发展趋势，以及农业有限水量应能实现的生产能力，尚远示成为现实生产力的实际，分析了节水型农牧生产结构、耐旱型的种植业结构、径流农业技术、蓄水保墒技术改进、灌溉农田效益增进、抗旱化学制剂应用，以及宁南地域资源优势等有关整体技术宏观块择和单一旱作技术的结合，在宁南旱农生产中的作用及进一步发展前景。  相似文献   

4.
宁南山区土地利用和开发战略探讨   总被引：2，自引：0，他引：2  
宁南山区地表结构复杂，是典型的温带大陆性半干旱偏旱季风气候。在调查分析土地利用现状特点和存在问题的基础上，提出统一规划，合理布局；增加肥料投入，改良培肥土壤；推广和使用旱作农业丰产技术，发展集流农业和节水灌溉技术；开发区域名优特产，建立绿色食品生产基地；以饲草生产为突破口，加速发展畜牧业经济的区域土地开发战略措施。  相似文献   

5.
宁夏南部山区旱作农业开发战略研究   总被引：10，自引：0，他引：10  
宁夏南部山区属半干旱区 ,90 %以上的耕地为旱地 ,加速旱作农业开发 ,对促进该区域经济全面发展具有十分重要的战略意义。本文论述了旱作农业开发在宁南山区的地位与潜力 ,提出了相应的技术需求。针对区域资源特点提出该区域旱作农业开发的三个战略阶段 :即强农促牧、农牧并举和稳农重牧阶段  相似文献   

6.
宁南农业持续力及持续发展   总被引：5，自引：2，他引：3  
依据宁南资源特点及土地承载力，分析了宁南农业的持续能力及障碍因素。宁南光热资源丰富、土地广阔、降水生产潜力大、有一批稳定的科技队伍及较高水平的科技贮备，具有农业持续发展的物质基础和条件，但生态环境恶劣、自然灾害频繁、人口增长过快、农业投入不足，又是农业持续发展的主要障碍因素。为此，应采取退耕还林还牧、严格控制人口、强化农业投入、发展宁南优势产业的持续发展战略及技术。  相似文献   

7.
立足宁南旱地小杂粮生产现状,通过分析影响产业化发展的主要限制因子,提出了以持续增进降水生产潜力,提高降水利用率和农田水分效率为重点,大力推广优质高效抗旱新品种及配套栽培技术、优化集成抗旱节水农业技术、培肥土壤、建设高产稳产基本农田、加强产业化开发等关键技术。  相似文献   

8.
宁南山区苜蓿产业化生产浅析   总被引：3，自引：0，他引：3  
通过对宁南山区发展苜蓿及其产业化生产的气候条件和市场前景等有关因素及存在问题的深入分析，指出发展苜蓿产业化生产是刺激当地生态农业和经济结构调整的必由之路，并提出了宁南山区积极推进苜蓿产业化生产的发展对策。  相似文献   

9.
宁南山区农业发展的困境与出路   总被引：2，自引：1，他引：2  
通过对宁南山区农业现状的分析表明，人口超载，水土流失和自然灾害频繁是制约宁南农业发展的主要障碍，同时也可以看出，随着农业基础设施的不断建设，农业生产力潜力还很大，控制人口保持水土和发展宁南草牧业是摆脱农业发展困境的战略举措。  相似文献   

10.
根据宁南山区的实际情况，在注重生物培肥的同时，应适量增加化肥投入，走有机与无机相结合的培肥土壤的途径。适当当地生物培肥土壤的措施有：合理轮作，增施有机肥，夏季绿肥压青和秸秆还田等，其中以合理轮作更具有现实性和普遍意义。  相似文献   

11.
Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.  相似文献   

12.
Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.  相似文献   

13.
We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.  相似文献   

14.
The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.  相似文献   

15.
Plant Viruses Transmitted by Whiteflies   总被引：18，自引：0，他引：18  
One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.  相似文献   

16.
《干旱区科学》2014,(6):782-782
正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad  相似文献   

17.
Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.  相似文献   

18.
A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVYN strain and six to the PVYO strain. No PVYC was found. Two other isolates reacted serologically like PVYO, but were unable to elicit a hypersensitive response from the Nytbr gene and probably represent the PVYZ group. At the molecular level, these two isolates showed a combination of both PVYO and PVYN and could be recombinants of these strains. Another isolate reacted serologically like PVYO, but induced vein necrosis in tobacco, like PVYN-Wilga. Some PVYN isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVYNTN group. The PVYNTN, PVYN-Wilga and PVYZ groups probably represent pathotypes within strains PVYN and PVYO, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.  相似文献   

19.
The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.  相似文献   

20.
Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.  相似文献   

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