甘肃省粮食产量时空变化、驱动因子和趋势预测分析

在分析甘肃省粮食产量时空变化的基础上,利用灰色关联分析方法探讨了粮食生产的影响因素,定量分析了粮食产量与影响因素的关联程度,并利用GM(1,1)模型对单产、年末总人口、粮食总产量的变化趋势进行了模拟预测.结果表明:(1)甘肃省粮食产量变化的总体特征为波动中呈上升趋势,各市(自治州)粮食生产变化空间差异性明显;(2) 粮食单产、年末总人口、有效灌溉面积、受灾面积、年末耕地面积和粮食播种面积等是粮食生产的主要驱动因子;(3)模拟预测表明,粮食总产量增长幅度不大,而人口的增长相对较快,因此,在大力发展粮食生产的同时,要适当控制人口数量,促进粮食生产可持续发展 .     

渭干河-库车河三角洲绿洲棉花种植面积时空变化特征分析

利用研究区棉花种植面积和产量相关统计数据,探究研究区棉花种植面积和产量的时空变化特征及单产和面积作用对棉花产量的影响。研究结果表明：(1) 近62年来,研究区的棉花种植面积、棉花产量和单产均呈上升趋势,而且表现出明显的阶段性和波动性,1949—1985年间增长缓慢,1986—2011年增长迅速。(2) 就棉花总产波动来看, 单产的作用占42.04%,面积作用占50.96%,在1949—1985年间单产增加对棉花总产量提高的贡献较大,在1986—2011年间棉花种植面积扩大对棉花总产量提高的贡献较大。(3) 1985年前棉花种植面积较稳定,波动不大,主要靠挤占粮食作物面积来扩大,1986年之后棉花种植面积扩大迅速,主要途径为开荒造地。(4) 棉花市场价格的波动、生产成本的上升、产量的徘徊、生产环境的恶化和品种等直接影响着研究区棉花生产的竞争力和棉农增收。     

自然灾害对山东省粮食生产影响的实证分析

自然灾害对粮食安全和粮食产量稳定具有极大影响。文中采用山东省1978~2012年粮食生产相关数据,分析了自然灾害对粮食生产的影响程度。首先,从粮食单产量入手,将粮食单产量分解为技术因素、社会因素和自然因素的影响。结果表明:自然因素是影响粮食单产量的首要因素,具体影响程度约为59.50%;其次,运用脱钩理论分析了山东省自然灾害对粮食总产量的影响。结果表明,目前自然灾害与粮食产量表现为扩张耦合的关系,粮食总产量仍受到自然灾害的强力束缚。     

新疆粮食生产波动:波动特征与影响因素

运用1999年以来新疆粮食生产的相关数据,采用粮食生产波动指数通过测算波动周期和波动幅度对新疆粮食生产的波动特性进行了计量分析,并通过构建理论模型对新疆粮食生产波动的影响因素进行了探讨。结果表明:1)1999~2014年新疆粮食总产波动经历了一个波浪式前进、螺旋式上升的过程,且整个波动过程可划分为5个周期;2)从波谷年总量增长率来看,新疆粮食总产波动属于古典型波动;从波动年距来看,总产波动属于典型的短期波动类型,但却有逐步进入较长周期波动的趋势;从波幅来看,三个完整周期波幅均大于5%的波动水平,但有进一步缩短的趋势,说明在未来一段时间新疆粮食生产的稳定性将提高;3)1999~2014年新疆粮食自然波动对总产的影响要大于经济波动的影响,说明新疆粮食生产波动更易受自然因素(自然灾害)影响;4)影响新疆粮食产量波动的因素主要有农业机械总动力波动、化肥施用量波动、上一年粮食收购价格波动以及成灾面积,其中,成灾面积波动对新疆粮食总产波动的影响最大,其次是农业机械总动力和化肥施用量,上一年的粮食收购价格对总产波动影响最不显著。     

近50年内蒙古自治区粮食产量波动影响因素分析

本文在近50年内蒙古自治区粮食产量和气象数据的基础上,对内蒙古地区粮食单产波动及其影响因素作了分析,结果表明:全区粮食产量按平均每年3.58％的速率递增。天气条件对产量的影响变化剧烈且连续性差;技术因素影响呈平稳上升趋势;其他因素影响略显波型波动。三种因素对产量影响的平均年际变化幅度分别为每公顷±749.8,±60.5和±187.7kg。在对气象产量作预报时不宜采用常用的趋势产量和其他因素产量的时间外延预报方法作预报,而应视当地具体的气候因子特征采用回归分析等方法作预报。本文选取了内蒙古中、东部两个代表不同气候条件的地区进行了气象产量模拟。     

陕西省粮食生产与粮食安全趋势预测

基于移动平均法,应用陕西省近31 a粮食产量数据对其未来10a粮食综合生产潜力进行了短期预测.结果表明:陕西省粮食单产提升幅度较小,年均每公顷增长46.2 kg;粮食总产上升缓慢,年均增长10万t;在粮食产量构成中,小麦产量及其比例下降,玉米产量及其比例上升,水稻与大豆产量及其比重变化较小;各粮食作物单产均稳步提升;人...     

新疆耕地和粮食灰色关联分析

收集整理1949—2003年新疆耕地、人口与粮食等资料,定量分析耕地的数量变化、质量状况。用线性回归法预测人口变化趋势。对粮食生产与其影响因素进行灰色关联分析,分析表明粮食单产、有效灌溉面积对粮食产量的影响最大,农业现代化的影响需要进一步加大,粮食收购价格指数对粮食生产不会有更大的影响。提出增加科技投入提高单产、发展节水农业等挖掘耕地潜力增加粮食产量的途径。为新疆今后农业发展决策提供科学依据。     

内蒙古乌兰察布盟农业土地利用变化对粮食稳产的影响分析

分析了内蒙古乌兰察布盟在降水波动剧烈、旱灾频繁的情况下,农业土地利用程度和结构变化对粮食生产稳定性的影响及其稳产的原因。该盟通过增加农田投入,改变农田利用的程度增加粮食趋势产量,从而抵消了粮食气候产量的波动,使粮食生产稳定性增强。还通过调整家作物种植结构,选种高产、抗旱作物,使粮食产量趋于稳定。     

1980～2009年新疆粮食生产主要影响因素分析

运用灰色斜率关联度和生产函数2种方法,分析了新疆1980～2009年粮食生产的影响因素及其贡献率.2种方法分析结果一致地表明,新疆1980～2009年粮食产量的增长主要取决于农业机械总动力、化肥施用量和有效灌溉面积三个方面;分时段来看,有效灌溉面积和粮食播种面积对新疆粮食产量的影响程度不断增强,而农业机械总动力和化肥施...     

GIS支持下的陕西省粮食生产时空变异研究

综合应用变异系数、重心迁移模型、比较优势模型以及统计学和GIS分析方法,探讨了1980-2009年陕西省粮食生产时空格局演进过程。结果表明:陕西省粮食生产总体变化显著,粮食产量呈波动增长趋势,但粮食种植面积不断减少将危及区域粮食安全;根据粮食产量高低和生产稳定性特征,将陕西省分为高产低变型(宝鸡、咸阳、渭南、汉中)、低产低变型(安康、商洛)、高产高变型(西安)、低产高变型(榆林、延安、铜川)四个粮食类型区;各地区人均粮食产量差异较大,铜川、西安和商洛粮食紧缺,宝鸡、咸阳、渭南和榆林粮有盈余,延安、汉中和安康粮食基本自给;粮食生产总体分布不均衡,南北差异较大,重心移动的阶段性明显,总体呈"北上东进"的移动趋势;各类粮食作物具有比较优势的区域分布具有一定规律,小麦、玉米和大豆、稻谷生产具有优势的地区分别在关中、陕北、陕南。研究结果以期为粮食安全背景下的区域粮食生产宏观布局与优化以及农业的结构调整提供较为科学的决策依据。     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

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.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

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.     

A survey of the genera of<Emphasis Type="Italic">Microgaster</Emphasis> latreille and<Emphasis Type="Italic">Hygroplitis</Emphasis> thomson (Hymenoptera: Braconidae: Microgastrinae) from China

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.     

Plant Viruses Transmitted by Whiteflies

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.     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

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.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

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 PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

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.     

Characterization of Sclerotinia minor populations in Texas peanut fields

In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.     

Eyespot of Cereals Revisited: ITS phylogeny Reveals New Species Relationships

Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea, but clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.     

Tumours of Begonia and some other ornamentals,induced by Corynebacterium fascians

In 1975 many tumours were observed in plants ofBegonia Schwabenland grown in Aalsmeer. Submersion of the roots ofNicotiana megalosiphon seedlings in a homogenate of tumorous tissue, induced tumours after two weeks. Short periods of submergence yielded results similar to those obtained after longer periods. Tumour homogenates lost their infectivity after ten min at 50°C. Aphids transmitted the infectious agent.Treatment with propylene oxide did not inhibit infectivity completely. Filtration through a 450 nm filter removed the infectious agent.Tobacco tumor virus or a viroid could not be isolated. Cultures ofCorynebacterium fascians, isolated from tumours ofN. megalosiphon were highly infectious and induced tumours in healthyN. megalosiphon andBegonia. Tumorous tissue homogenates ofPelargonium zonale, Dahlia sp.,Gladiolus sp., andLilium sp. also caused tumours inN. megalosiphon, from whichC. fascians was isolated. It was not possible to produce tumours inN. megalosiphon with homogenates from roses with symptoms of bud proliferation.Samenvatting In 1975 werden vele tumoren waargenomen inBegonia Schwabenland op Aalsmeerse bedrijven (Fig. 1). De infectiositeit van tumorweefsel kon goed en snel worden vastgesteld door de wortels van zaailingen vanNicotiana megalosiphon in een homogenaat van tumorweefsel te dompelen. Tumoren ontstonden na twee weken, de eindbeoordeling geschiedde na een maand (Fig. 2). Ook verschillende andereNicotiana spp.,Melilotus officinalis (Fig. 3) enPisum odoratum (Fig. 4) werden aangetast.Bij de infectiositeitstoets gaven zeer korte dompeltijden even goede resultaten als langere (Tabel 1). Infectieus sap verloor zijn infectievermogen na 10 min verhitting bij 50°C. Bladluizen brachten de smetstof over. Propyleenoxide verminderde de infectiositeit wel, doch onderdrukte deze niet totaal. Bij filtratie door een 450 nm filter bleef het infectieuse agens op het filter achter. Het tumor-inducerende agens was ook aanwezig in die delen van planten met tumoren welke gezond leken en het ging voor een gering deel over met zaad (Tabel 2).Uit tumoren konden wij geen tabakstumorvirus of een viroïde isoleren. Culturen vanCorynebacterium fascians, geïsoleerd uit tumoren vanN. megalosiphon bleken zeer infectieus en veroorzaakten tumoren inN. megalosiphon enBegonia. Homogenaten van tumorweefsel vanPelargonium zonale, dahlia (Fig. 5), gladiool (Fig. 6) enLilium Mid Century Hybrid Enchantment (Fig. 7) veroorzaakten ook tumoren opN. megalosiphon, waaruitC. fascians werd geïsoleerd. Met sap van kroeskopzieke rozen konden wijN. megalosiphon niet besmetten.