种稻农户品种更新行为及影响因素分析——基于湖南省的调查

良种是农业生产发展的关键要素之一,通过发现主导当地农户品种选择的主要因素,积极引导农户有序更新,从而充分发挥良种对于农业生产发展的巨大作用,有利于提高粮食产量和质量,增加农户的收益。此文以湖南省3个双季稻主产区乡镇的144户农户为调查对象,对种稻农户的早晚稻品种采用行为进行了问卷调查,总结了影响种稻农户水稻品种更新行为的外部主导因素,并运用三分类的Logistic模型对影响种稻农户的品种更新行为的内部因素进行了进一步的实证分析,基于调查和分析结果认为,目前农业科技推广机构对农户的品种更新仍起着重要的引导作用,而农户长期积累的种植习惯是影响其品种更新行为的重要因素之一,并由此提出了相应的对策建议。     

黑龙港区小麦玉米农艺节水技术集成模式综合评价及推广建议

黑龙港属华北缺水低平原区,水资源不足是限制该区农业生产发展的主要因素。该区主要种植模式为冬小麦－夏玉米一年两熟制,小麦、玉米高产主要靠超采地下水来维持。近年来,随着小麦节水技术的推广应用,粮田产量和水分效率在逐步提高,但节水高产潜力仍然巨大。特别是从周年水资源高效利用出发,建立区域特色的两熟一体化节水高效技术模式,十分必要。运用熵权综合评价法对“黑龙港及鲁北平原区小麦玉米减蒸降耗农艺节水技术集成与示范”项目形成的小麦玉米农艺节水技术集成模式进行评价,筛选出最佳的节水技术模式。得到的结论是：最少水肥投入模式最优,节水省肥模式次优,传统高水肥模式最差。节水省肥是未来发展现代农业的方向。应该进一步提高农户农业节水意识,利用多种手段,促进农户采用小麦玉米节水技术优化模式。     

影响农作物秸秆处置利用的因素分析

中国是世界上的一个农业大国,农业生产中产生大量的废弃物,这些废弃物的不当处置严重地危害了环境,影响了农业的可持续发展。通过对江苏省农户的实地调查,从农户的微观视角集中研究农户对农作物秸秆处置利用方式的选择方式及其影响因素,调查资料显示,农户主要是通过焚烧弃置和综合利用两种方式处置农作物秸秆。运用Logit二元选择模型的回归分析,发现农户在选择农作物秸秆的处置利用方式时受到了农户的个人身份特征、农户的家庭特征、农户的生产经营特征以及农户所处的地区等因素的影响。     

如何发展休闲农业

正休闲农业(包括乡村旅游在内),是指以城市居民为主要客源市场,以开发利用具有旅游价值的农业景观资源和农村人文资源为手段,将观光、休闲、度假等旅游休闲功能与农村生态、农业生产、农户生活、农耕文化及农村民俗等三农要素有机融合的特色农旅产业。发展休闲农业有哪些模式可以借鉴     

黎平县家庭农场第一张食品生产许可证落户天益茶场

正2017年9月1日,从贵州省黎平县市场监督管理局获悉,黎平县天益农(茶)场获得食品生产许可证(SC),成为黎平县家庭农场群体中的第一张食品生产许可证。据悉,家庭农场是指以家庭成员为主要劳动力,以农业收入为主要来源,有一定稳定性和适度规模的农业经营单位。家庭农场对实现农业集约化、专业化和组织化,对激发农户的科技需求和应用,对农业文化的传承,对耕地的保护和可持续利用,对培育新型职业农民等有一定的积极促进作用。     

加快发展广东农业产业化经营的路径探讨

广东省农村居民人均纯收入与城镇居民人均可支配收入的差距从1989年以来呈连续扩大的趋势,已成为广东构建和谐社会和率先基本实现现代化的“瓶径”。实践证明农业产业化经营是中国农业经营体制的重大创新,是实现中国各地农村经济结构战略性调整、农业增效农民增收的重要路径之一。笔者在深入分析广东省农业产业化经营的现状和存在的问题后,提出了大力扶持农业产业化龙头企业、引导农业龙头企业与农户建立紧密型利益联结机制、积极引导农业龙头企业创办农业产业化生产基地、积极培育农民专业合作经济组织、设立政策性的贷款担保基金和农产品保险基金等路径     

基于SWOT分析的石城县现代烟草农业发展策略探索

运用SWOT分析法对石城县发展现代烟草农业的优劣势及机遇和挑战进行系统论述,研究表明,石城县发展现代烟草农业在生态条件、生产经验、烟叶特色和农工商结合上具有优势,但在地形地貌、农田基础设施和耕地流转方面存在一定的劣势,从自身发展条件和宏观发展环境看,机遇大于挑战。为此研究有针对性地提出相应的发展策略建议,主要包括：以烟叶基地单元现代烟草农业建设为契机,优化烟叶生产环境,提升防灾减灾能力;鼓励耕地流转,推进烟叶规模化经营;以信息化建设为载体,提升烟叶生产组织管理水平;推进专业化分工,提高社会服务水平。进一步深化农工商合作,突出特色优质烟叶生产。     

城乡统筹发展中农业非点源污染控制的农户行为管理研究

为了将农户的“有限理性”纳入政府对农业非点源污染农户行为管理分析框架中,为政府治理非点源污染提供相应政策参考,在 “有限理性”假设下,基于城乡统筹发展中农户行为的“集体表现”视角,运用“复制动态”方法,研究非点源污染控制的农户行为演化过程,分析政府在农户行为从初始状态到“演化稳定策略”过程中的作用。结果表明,农户“有限理性”使农业非点源污染控制的农户生产生活行为存在不确定性,但在与政府监督行为的长期博弈中,农业非点源污染控制的农户生产生活行为存在“演化稳定策略”。为促进这一稳定策略均衡,需要政府积极参与,并采用相关措施激励农户采用能使农业非点源污染排放达标的生产生活行为。     

新时期北京农户绿色农业生产意愿及其提升路径研究——基于TAM和SEM的农户感知与政策因素影响分析

为推动北京地区绿色农业高效发展,了解广大农户的绿色农业生产意愿并寻求可靠提升路径意义重大。本研究借鉴技术接受模型的分析框架,将意愿的影响因素设计为农户感知和政策因素两大类,利用北京市10个区350个农户的调查数据,采用结构方程模型系统分析了农户感知与政策因素对农户绿色农业生产意愿的影响效果及其相互关系。感知有用性和政策响应对农户参与绿色农业生产意愿具有显著正向影响;感知易用性通过感知有用性的中介作用对意愿产生影响;政策执行力通过感知易用性、感知有用性和政策响应的中介作用对意愿产生影响。并对各因素的综合影响力进行了比较。基于以上分析,提出提升北京农户绿色农业生产意愿的路径建议：采取有效措施提升农户对发展绿色农业有用性和易用性的认知;科学合理设计有效政策,力求提升政策响应效果;强化政策执行落实,发挥政策应有效力。     

四川省攀枝花市烟农种植意愿及影响因素分析

为稳定烟农队伍,引导烟农高质量生产,促进烟草行业的可持续发展,运用二元Logistic模型和攀枝花市3个烤烟主产区242户烟农的调查数据,分析农户种植烟草的意愿及其影响因素。结果表明,户主的年龄及参加农业专业知识培训的经历对烟农种植意愿具有正向的显著性影响,农户是否兼业、农户的家庭人口数量及非烟作物收入对烟农种植意愿具有负向的显著性影响。由此建议加强专业知识培训、引导烟农专业化生产、优化农村农业从业人口结构,这将有利于正向强化烟农生产积极性,进而通过种植经济作物达到农民收入持续增长、地区农业稳步发展的效果。     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.