对书写工具的选择与预防近视的认识和建议

从字迹是视觉信号这个角度来说,中小学生写字时最好使用较软质的铅笔或用钢笔。如果说低头歪头写字达不到书写＂三个一＂的要求,是孩子们＂喜欢低头歪头＂,那么众多家庭从孩子小的时候就手把手地教孩子怎样握笔写字、上学后老师又是那么耐心地教学生如何正确执笔书写,反而还有如此多的学生还是很难达到书写＂三个一＂的要求呢？     

我国被征地农民权益保护问题探析

对目前我国的征地问题进行思考,可对有效化解政府与农民冲突以及保护农民权益起到一定的启示作用。     

嫩江源湿地保护措施的探讨

实施嫩江源湿地保护及恢复项目,建立、健全保护管理网络,开展湿地保护及科学监测,恢复已经遭到破坏的湿地植被,不仅十分必要,而且符合我国湿地保护的方针和政策,符合我国湿地保护行动规划.     

云南省岩溶地区石漠化草原现状及分区保护与修复策略

据最新调查数据,云南省石漠化草原主要分布于曲靖、昆明、红河等5个州( 市),总面积 37.97 万hm²,占岩溶土地面积的3.53%,其分布最广的海拔区间为1 500~2 500 m,占比47.85%, 基岩裸露度分布区间为30%~94%,以植被盖度为10%~19%的分布区间面积最广,占比37.85%, 绝大部分分布于土层薄甚至极薄区域,占比达92.10%。根据石漠化草原空间分布特征,在充分衔 接各大生态保护和修复工程建设规划基础上,统筹考虑岩溶生态系统的完整性、地理单元的连续性 和经济社会发展的可持续性,将云南省石漠化草原区划为6个分区,分区阐述石漠化草原生态保护 与修复策略。     

我国农村环境教育的重要性

在我国农村,环境污染所造成的环境质量下降已经对农业经济的发展和人们的身体健康产生了严重的影响。为提高农村环境质量和推进新农村建设,阐述了对领导干部、农民和企业这3个群体的环境教育,提高他们的环境意识,为我国经济持续健康的发展奠定良好基础。     

信息管理系统开发中的知识产权保护

通过分析信息管理系统建设中面临的知识产权保护问题,包括信息采集中的知识产权保护保护,信息利用与服务中的知识产权保护,数据库的知识产权保护,以此为基础,提出了信息管理系统建设中知识产权保护相对策略。     

A Severe Hellenic CMV Tomato Isolate: Symptom Variability in Tobacco, Characterization and Discrimination of Variants

A severe strain of Cucumber mosaic virus (CMV) originating from an infected tomato plant (Gastouni-Olympia, Greece) was isolated in tobacco (Nicotiana tabacum cv. Xanthi nc), after three serial local lesion passages in Chenopodium quinoa and designated CMV-G. CMV-G induces yellow mosaic (YM) symptoms in tobacco. When CMV-G was passed mechanically through C. quinoa, phenotypic variants inducing YM or green mild mosaic (MM) in tobacco were isolated. Aphid transmission, from different hosts, appears to be an effective approach for separating MM variants of CMV-G from YM variants. In particular, aphid transmission from zucchini proved to be very efficient in selecting for MM variants. In contrast, aphids transmitted only YM variants from tomato plants. Molecular characterization of CMV-G and its progeny resulted in their classification in the CMV subgroup IB, free of satellite RNA, being the first discovery of the subgroup IB in Greece. In the Solanaceae family (tobacco, tomato, pepper) YM variants induced more severe symptoms than the MM variants. YM and MM phenotype was stable in tobacco for all seven passages tried using the obtained YM and MM variants. Cross-protection experiments showed that an isolated MM variant was able to protect tobacco plants against a challenge infection by a YM variant.     

Problems of implementing compulsory integrated pest management

Compulsory integrated pest management poses a number of challenges and issues for debate. Some of are discussed with reference to European Union requirements set out in Annex III of Directive 128/2009. Requirements on the use of plant protection products bring with them problems with dose reduction in the light of a resistance prevention strategy, the lack of threshold levels, the necessity of chemical treatments and the limited availability of effective products of biological origin. Use of preventive measures of pest control faces barriers related to profitability and a lack of knowledge on the part of farmers. Challenges to control the system, as well as the fact that some legally enforced rules are not suitable for all crops, seem also to be an issue. © 2019 Society of Chemical Industry     

简论我国施药技术的发展趋势

环境安全和食品安全已引起世界各国的高度重视,我国政府在全面建设小康社会的同时,已把治理农业环 境、发展可持续农业列入重要的议事日程。本文试图从施药技术的3个方面--药械、农药、施药方法来探讨我 国施药技术的发展趋势,并提出了作者的一些观点,力图为我国施药技术的发展提供一些参考依据。