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81.
Zea mays has been historically imported to Japan via two independent geographical routes: into southern Japan by trading with Europe in the 16th century and into northern Japan by import from North America in the 19th century. Breeding to genetically improve on quality traits and high yields has led to the current domestic landraces in each region. In a survey of 82 domestic landraces, nine out of 38 landraces originating from southern Japan showed complete immunity to cucumber mosaic virus yellow strain (CMV(Y)) without the formation of necrotic local lesions (NLLs). In contrast, three out of 44 landraces originating from northern Japan developed NLLs, but revealed no systemic spread of the virus. Due to the absence of good documentation on NLL formation in Z. mays, the response of domestic landraces Aso‐1 and Aso‐3, originating from Ibaraki in northern Japan, to a challenge with CMV(Y) and CMV(Ma‐1) was further analysed. Aso‐3 only formed NLL in response to CMV(Y) but not to CMV(Ma‐1). Moreover, in CMV(Y)‐inoculated Aso‐3, virus spread was restricted to the primary infection site and the expression of defence‐related genes was up‐regulated, whereas Aso‐1 became systemically infected with either CMV(Y) or CMV(Ma‐1). The response of Aso‐3 to CMV(Y) was inherited as a single dominant trait. Together, these results pointed towards the induction of hypersensitive response (HR)‐mediated resistance to CMV(Y) in Aso‐3. Although HR‐mediated resistance to viruses has been studied mainly in dicots, the pathosystem CMV–Z. mays may provide a model to investigate HR‐mediated resistance to viruses in monocot plants.  相似文献   
82.
Ambrosia artemisiifolia is an annual weed from North America that nowadays is invasive in many countries worldwide. In Austria, numerous populations of A. artemisiifolia are located along the Danube River, especially along the ‘New Danube’ (Vienna). This area is characterised by ruderal and riparian sites, which are regularly flooded. To better understand the spread of A. artemisiifolia and its colonising behaviour along the Danube River, we analysed genetic structure and diversity based on 23 populations linearly arranged along the Viennese Danube riverbed and upstream, utilising the Amplified Fragment Length Polymorphism (AFLP) fingerprint method. We generated 284 polymorphic AFLP markers across 446 A. artemisiifolia plants. The genetic diversity within populations was higher (HW = 0.091) than among populations (HB = 0.007). This result indicates A. artemisiifolia introductions from similar mixtures of sources or spread from a single already mixed introduction. Within our local setting, we were unable to identify neither source or sink populations nor an obvious linear genetic structuring. Genetic among‐population differentiation was low to moderate (amova ‐derived FST = 0.124). Lack of geographical structuring is indicative of highly dynamic gene flow, which is further supported by the absence of an isolation‐by‐distance pattern. Multiple introductions and non‐directional gene flow are most likely promoted by anthropogenic disturbance and human‐mediated dispersal. Our results demonstrate the ability and speed of A. artemisiifolia to settle in newly disturbed areas and the difficulties to predict invasion directions, as downstream river dispersal was negligible.  相似文献   
83.
Payments for environmental services (PES) are conservation instruments in place in various Latin American countries. They are generally undergoing adjustment and implementation changes, and they are widely implemented in indigenous communities. This article aims to suggest a relevant group of context variables in PES implementation. Characterizing the local context of two indigenous communities located in Oaxaca, Mexico, and analyzing the relationship between the local context and PES implementation and outcomes perceptions.

The work is based on 75 surveys administered to beneficiary families of the instrument in the two localities. The results suggest three conclusions:

The pertinence of the nine focal variables: “Forest cover, Opportunity costs, Livelihoods, Trust and cooperation, Motivations toward conservation, Management practices, Internal organization, Land tenure and Rules for the management and use” to the characterization of the local context. And the relevance of the new focal variable “Presence and experience with Civil Society Organizations”.

The coincidence between the contextual variables and the determinants of the success of conservation instruments.

Finally, the incidence of “Trust and cooperation” and “Internal organization” in the implementation of equitable PES schemes. And the importance of linking sustainable production to PES conservation schemes.  相似文献   

84.
油菜机械移栽载苗基质块力学与生物学特性分析   总被引:4,自引:3,他引:1  
为保证油菜载苗基质块具有良好的机械移栽适应性和幼苗生长质量,该文针对油菜机械移栽过程中载苗基质易出现破损导致取送苗失效问题,以正方体油菜载苗基质块为研究对象,对载苗基质块力学特性和生物学特性进行研究,开展以基质成分配比(蚯蚓粪:黄棕壤∶蛭石混合体积比为1∶2∶1、1∶1∶1和2∶1∶1)、基质压实度(基质与穴孔体积比为1.0、1.2和1.4)、硼硒营养液浓度(0.24%、0.27%和0.30%)为因素的正交试验。结果表明:基质成分配比和基质压实度对油菜载苗基质块力学特性影响分别为极显著和显著;基质成分配比及基质压实度对幼苗壮苗指数影响极显著,硼硒营养液浓度对其影响显著;基质成分配比和基质压实度均对基质包裹度及根系健壮度影响极显著,硼硒营养液浓度对基质包裹度及根系健壮度影响显著。采用综合评分法得出基质成分配比为1∶1∶1、基质压实度为1.2、硼硒营养液浓度为0.30%时油菜载苗基质块力学特性及幼苗生长质量较优。对上述因素组合所育油菜载苗基质块进行台架试验可知:在移栽机横向推苗速度20 mm/s,同步输送带速度30 mm/s,取苗频率40株/min试验条件下,基质损失率为2.57%、送取苗成功率为90.93%,满足机械移栽需求。  相似文献   
85.
新农科建设背景下地方农业高校教育改革探索   总被引:3,自引:0,他引:3  
新农科建设已经成为新时期农业高校教育教学改革的重要方向,要从现代农业产业转型的新变化、实施乡村振兴战略的新需求、新时代高等教育发展的新趋势、生态文明建设的新挑战等不同维度深入理解新农科建设的时代背景。地方农业高校在新农科建设中要树立核心理念:坚持立德树人与投身乡村振兴战略紧密融合、坚持卓越农林人才培养与应用型人才培养紧密融合、坚持新农科新工科新文科建设互相支撑紧密融合、坚持高校专业改革人才培养与产业(企业)紧密融合、坚持高校与区域发展紧密融合。研究以沈阳农业大学教育改革实践为案例,进一步探讨地方农业高校新农科建设的具体路径:把立德树人作为新农科人才培养的根本、扎根东北服务东北突出新农科建设与行业企业协同,以学生为本重点关注学生阶段成长发展目标、强化专业自评估实现专业动态优化调整、人才培养注重四个教育模块融合、突出学教融合实现学生学习回归与教师教育人回归融合。  相似文献   
86.
以本校的民族地方文献资源为例,提出了民族高校图书馆在民族地方文献的宣传以及开发利用方面应采取的措施。  相似文献   
87.
信息素质是当今社会中人的综合素质的重要组成成分,是学习型社会中个人终身学习的必备素质之一。信息素质教育是培养高素质人才的重要手段。在对地方高校部分在校大学生信息素质状况调查与分析的基础上,提出了信息素质教育机制创新的一些措施。  相似文献   
88.
细叶韭调味品的产业化初探   总被引:2,自引:0,他引:2  
通过对细叶韭生产现状及开发利用价值的分析,对细叶韭调味品的产业化进行了探讨。结果表明:细叶韭作为新型调味品受到市场的青睐,但基本处于野生采收阶段。细叶韭作为新型调味品资源,对餐饮业和食品加工业具有不可替代的作用,对于特色产业的形成,具有重要意义。细叶韭属于劳动密集型产业,发展细叶韭产业,可安排大量农村剩余劳动力,为贫困山区的发展,注入新的活力,将资源优势转化为经济优势,促进区域经济的发展。应加大对细叶韭研究的投入,增加研究课题,加强基础研究,为细叶韭产业化奠定坚实的理论基础。  相似文献   
89.
随着我国职业教育改革的发展,农业高职院校茶果专业应结合地方茶产业发展,将教学与实践合理整合,制订适应地方茶产业需要的教学与合作模式,最终达到校企双赢。  相似文献   
90.
研究采用L9(34)正交试验法和感官评定法研究了玉米纤维添加量、油脂添加量、疏松剂添加量等对纤维饼干品质的影响。结果表明,最佳饼干品质的工艺条件为:面粉100%,玉米纤维10.0%,精炼植物油11.0%,疏松剂1.2%,白砂糖15.0%,小苏打0.9%,碳酸氢铵0.3%,食盐0.4%。  相似文献   
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