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1.
MAIN ABSTRACTS     
《长江大学学报》2013,(5):I0001-I0003
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2.
MAIN ABSTRACTS     
《长江大学学报》2013,(7):I0001-I0005
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3.
A field survey and policy proposal for Information acquiring ability of Shandong Farmers: Proof from 6 villiages in Jinan and Rizhao Fei Liang Yanhui Xu
Abstract: Informatization is one of the most important trends in agricultural and rural development. So there should be a lot of new farmers who have mordern information sense, master application of information, acquire enough information ability. Based on the field survey for 6 villiages in Jinan and Rizhao, we have found reality and problems in the information acquiring of Shandong farmers. Our research includes information acquiring channels, information demanding sense and content and information screening. Some policy proposals were presented in our research.  相似文献   

4.
Discussing the Issues of Agriculture, Farmer and Rural Area in the Framework of Scientific Outlook on Development Kai Wang Abstract: Issues of agriculture, farmers and rural area have become the key point as well as the bottleneck to build a well-off society in an all-around way. Since the founding of PRChina, the issues of agriculture, farmers and rural have come through with the period of free flowing between urban and rural/urban and rural segregation period and urban and rural interacts period. Although the issues in the different period do not perform exactly in the same way, they have the deep theory and practical logic. It is right that the accumulation of the history problems that makes the issues the top priority. The perspective of scientific outlook on development extends the cognition boundary of the issues, which, at the same, provides us with the methodology guidance. Therefore, to solve the agriculture farmer and rural area problems, we should carry out the perspective of scientific outlook on development, take development as the first task for our party, insist in people oriented, strike the balance between urban and rural, insist in unified accumulation of rural economic development and all-around coordinate and sustainable development.  相似文献   

5.
MAIN ABSTRACTS     
《长江大学学报》2012,(1):I0001-I0003
01 A Penalty Function Method for Solving Linear Bi-level Programming
ZHANG Tao (State Key Laboratory of Water Resource and Hydropower Engineering Science ( Wuhan University), Wuhan 430072; Yangtze University, J ingzhou 434023) YANG Shi-ming (Yangtze University, Jingzhou 434023)
Abstract: By using the follower's K-T. condition, the linear bi-level programming is transformed into the monolayer programming, then we append the complementary condition to the upper level objective with a penalty. The theoretical analysis shows that the penalty function is exact. Finally, an algorithm is proposed for the linear bi-level programming and some numerical experiments are given to illustrate the algorithm.
Key words: linear bi-level programming; K-T condition; penalty function  相似文献   

6.
MAIN ABSTRACTS     
《长江大学学报》2009,6(4):I0016-I0016
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7.
MAIN ABSTRACTS     
《长江大学学报》2010,(1):I0007-I0009
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8.
In 2009, Agriculturtal Science & Technology's full-texts have been included by international authority of the search tools CAS. CAS is a team of scientists, creating and delivering the most complete and effective digital information environment for sci- entific research and discovery. CAS provides pathways to published research in the world's journal and patent literature-virtually everything relevant to chemistry plus a wealth of information in the life sciences and a wide range of other scientific disciplines- back to the beginning of the late lgth century.  相似文献   

9.
MAIN ABSTRACTS     
《长江大学学报》2012,(3):I0001-I0007
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10.
MAIN ABSTRACTS     
《长江大学学报》2013,(6):I0001-I0003
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11.
橘小实蝇在江西省的潜在分布区预测   总被引:1,自引:0,他引:1  
利用橘小实蝇的分布点数据和环境因子数据,通过GARP生态位模型预测了橘小实蝇在江西省的潜在分布区域。结果表明,橘小实蝇在江西省的适生面积占全省面积的2/3以上。在24~26°N赣南盆地的大部分区域,年平均气温在19~20℃,是橘小实蝇的高适生区;在26~27°N的赣州北部的部分地区以及吉安西南部、抚州、鹰潭、上饶东南部的少部分地区,年平均气温在18~19℃,是橘小实蝇的中适生区;在26~30°N的滨湖、赣江中下游、抚河、袁水区域和赣西南山区,年平均气温在17~18℃,是橘小实蝇的低适生区;赣东北、赣西北和长江沿岸地区,年平均气温为16~17℃,是橘小实蝇的非适生区。  相似文献   

12.
桔小实蝇飞行能力测定试验初报   总被引:25,自引:0,他引:25  
桔小实蝇Bactrocera(Bactrocera)dorsalis(hendel)是为害水果和蔬菜的检疫性有害生物,此虫具有较强的飞行能力,应用飞行磨系统在实验室条件下的测试,初步发现最远可飞行46.54304km的距离。  相似文献   

13.
刘建宏  熊小真  杨丽英  熊忠平  潘涌智 《安徽农业科学》2010,38(34):19396-19398,19430
[目的]为在江西省对桔小实蝇进行有效的监测和预警提供科学依据。[方法]利用桔小实蝇的分布点数据和环境因子数据,通过GARP生态位模型预测桔小实蝇在江西省的潜在分布区域。[结果]桔小实蝇在江西省的适生面积占全省面积的2/3以上。在24°~26°N赣南盆地的大部分区域,年平均气温在19~20℃,是桔小实蝇的高适生区。在26°~27°N的赣州北部的部分地区以及吉安西南部、抚州、鹰潭、上饶东南部的少部分地区,年平均气温在18~19℃,是桔小实蝇的中度适生区。在26°~30°N的滨湖、赣江中下游、抚河、袁水区域和赣西南山区,年平均气温在17~18℃,是桔小实蝇的低适生区。赣东北、赣西北和长江沿岸地区,年平均气温为16~17℃,是桔小实蝇的非适生区。[结论]该研究结果表明,桔小实蝇的实际分布与GARP的预测分布基本相符。  相似文献   

14.
为了探索柑橘小实蝇入侵扩散与危害规律,提高其监测与防控水平,2008—2010年应用柑橘小实蝇专用性诱剂和诱捕器,在全市19个镇(街道)35个柑橘园建立监测点进行全市性入侵扩散分布普查;在古城伏龙柑橘园和市区水果市场,建立2个系统监测点开展全年种群数量消长监测,结果表明柑橘小实蝇种群入侵扩散与时空分布呈塔型趋势,即以城区为中心,并呈向周边区域扩散蔓延趋势;全年种群时序数量变化主要呈单峰型曲线变化,一般于6月中下旬至7月上中旬初见性诱成虫,8月上旬形成增长拐点,9—10月形成数量高峰,影响种群数量消长的主要因子有种群基数、气候和生境条件等,从而创建柑橘小实蝇基数(m6)与全年种群诱量(M)关系模型M=23.8339m6+59.8003(n=6,r=0.9735**)、当旬虫口密度(mn)与其前3个月的旬平均气温(tn-9)关系模型mn=1.9248tn-9-14.88063(n=72,r=0.5123**),以及柑橘挂果期成虫诱量(M)、有虫株率(R%)、有虫果率(P%)、每虫果幼虫量(N)等关系模型:R=0.3667M-1.2746(n=11,r=0.8901**);P=0.0581R+0.3112(n=11...  相似文献   

15.
Invasion of the oriental fruit lfy, Bactrocera dorsalis, into new niches containing different food sources (a process referred to as host shift), may cause population genetic differentiation and sympatric speciation. To attempt to infer that experimentally, test populations were established by transferring a subset of the original populations, which had been grown on banana for many generations, onto navel orange, and then subculturing the navel orange population and banana population for at least 20 generations. Four pairs of SSR primers with high polymorphism on laboratory strains were used to detect population genetic differentiation. All six tested populations (the 5th, 10th and 15th generations of B. dorsalis fed on banana and navel orange, respectively) were found to have low genetic diversity. Furthermore, the genetic diversity of the navel orange populations was found to decline after being crossed for several generations. Populations initially were deviated from Hardy-Weinberg equilibrium, however, equilibrium was achieved with increasing numbers of generations in both of the host populations. Limited gene lfows were found among the six populations. The Nei’s standard genetic distances between the two host populations of the same generation were initially low, but increased with generation number. Genetic distances between banana and navel orange populations of the same generation were lower than genetic distances between different generations grown on the same host plant. Analysis of molecular distance (AMOVA) results based on generation groups and host groups demonstrated that genetic variation among generations was greater than that between the two host populations. The results indicated that population genetic differentiation occurred after the host shift, albeit at low level. Biogeography and taxonomy of the B. dorsalis complex revealed that speciation of B. dorsalis might be tightly associated with host shift or host specialization of B. dorsalis following dispersal.  相似文献   

16.
桔小实蝇寄主选择性的研究与应用   总被引:3,自引:0,他引:3  
综述了桔小实蝇成虫对寄主果实选择及应用的研究概况。桔小实蝇成虫对寄主果实的选择表现为对果实不同部位的选择、同种寄主不同成熟度果实的选择、同一寄主不同品种的选择、不同寄主果实的选择四个方面。桔小实蝇成虫对寄主果实的选择主要受果实挥发性物质(包括自然释放和虫害诱导释放)、果实的品质性状、颜色、取食经历及记忆行为和昆虫内共生菌等因素的影响。  相似文献   

17.
基于微卫星分子标记的重庆地区桔小实蝇遗传分化研究   总被引:2,自引:2,他引:0  
【目的】探讨重庆地区桔小实蝇遗传分化情况。【方法】以8对微卫星引物对重庆地区6个桔小实蝇种群155个个体的遗传多样性进行研究。【结果】在8个微卫星位点上共检测到51个等位基因。6个种群在各位点的平均表观杂合度Ho为0.1731—0.2958,平均期望杂合度He为0.1311—0.6796,经卡方检验,各种群在大多数位点上不符合Hardy-Weinberg平衡。对多态位点百分率P、基因多样性指数Nei’s,Shannon信息指数I的分析表明,本文所研究的6个桔小实蝇种群具有较丰富的遗传多样性。种群间分化系数FST平均值为0.0777,说明遗传变异主要发生在种群内。武隆种群和永川种群之间的遗传距离最大(0.2367),江津种群和北碚种群之间的遗传距离最小(0.0667)。UPGMA聚类分析显示,重庆地区桔小实蝇大致分为两个亚群,北碚、江津、万州、秀山、永川5个种群为一个亚群,武隆种群单独为一个亚群。【结论】重庆地区的桔小实蝇出现了一定的遗传分化,但分化程度不高。桔小实蝇在重庆地区的入侵处于初级阶段。  相似文献   

18.
潘涌智  黄忠  马玉梅 《安徽农业科学》2012,(30):14785-14787
[目的]了解苹果斑点落叶病菌(Alternaria mali Roberts)在云南省的适生区范围。[方法]利用苹果斑点落叶病菌在云南省的分布点数据和环境数据建立了Maxent生态位模型,并通过将其投影到地理空间预测了该病菌在云南省的潜在分布范围。[结果]苹果斑点落叶病菌在云南的潜在分布区为云南省中部和北部的大部分地区。最冷月份最低温对该病原菌的预测分布有重要影响,最冷季度平均温度次之。经ROC曲线分析法验证得出AUC值为0.998,表明预测结果是可靠的。[结论]为防止苹果斑点落叶病菌的传播和科学评估其危害提供了参考。  相似文献   

19.
The burrowing nematode (Radopholus similis) is one of the main quarantine pests in China, and the risk of invasion posed by this nematode is becoming more and more serious with regard to the international trade being intensified day by day. It is urgent to analyse the potential geographic distribution of R. similis in China. Genetic algorithm for rule-set prediction modeling system (GARP) and maximum entropy (MAXENT), the two niche models which have been widely used to predict the potential geographic distribution of alien species, were used to predict the distribution of R. similis in China. We also presented a model comparison of the results by both threshold-dependent and threshold-independent evaluations. It has been shown that the two niche models could be used to predict the potential distribution of R. similis reliably. The potential distribution of R. similis should be constricted within the south of China, such as Hainan, Guangdong, Guangxi, Fujian, Yunnan provinces, and Taiwan of China. The MAXENT gives a better prediction than that of GARP. R. similis can be introduced to China by flowers and nursery stock's international shipping. The predicted results indicate that R. similis can occur in south coastal area of China and Yunnan Province, which are the main flower and nursery stock's import-export areas in China. Consequently, a strong quarantine program is needed at the ports of such areas to prevent the pest from being introduced to China.  相似文献   

20.
2005~2006年通过诱剂诱集实蝇以及结合田间观察等方法,对六库地区实蝇种类的发生进行了监测调查研究,结果发现了7种实蝇(其中1种种名待定)。并对六库地区实蝇的种类、数量、寄主及危害情况等进行了分析报道。  相似文献   

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