小麦慢锈品种‘平原50’上条锈菌侵染的超微结构观察初报

用光镜和电镜观察以条中２８号小种接种的慢锈品种“平原５０”和感病品种“铭贤１６９”的病理组织和超微结构。光镜观察发现两品种在侵入阶段无明显差异。在接种５天后，两品种中的菌落大小，吸器个数上出现较明显差异。     

变频器监控技术分析

本文介绍了变频器网络的系统要求,通讯协议,组态设计等技术     

PP_(333)对温室葡萄枝条次生木质部细胞解剖结构的影响

为了研究设施栽培条件下葡萄木质部细胞的特征性结构及其受PP_(333)的影响,试验通过对温室葡萄喷施PP_(333)后的枝条次生木质部细胞的解离、观察,经统计分析,结果表明:(1)不同浓度PP333处理对各类型细胞的X形态结构没有明显影响;(2)浓度不同对各类细胞的长度和直径抑制作用不同,喷施1500mg/L浓度的PP_(333)对其营养生长的抑制效果最好。通过该试验的研究,为更好地探索设施栽培条件下果树的生理生态特征和化学调控技术提供了依据。     

植物组培育苗工厂电脑管理系统的设计与应用

研制了一个组培室数据库管理系统，通过检索可方便地查询培养室内各种瓶苗的动态变化和某种组培育苗状态及积累的组培育苗资料，为最适宜培养条件的电脑筛选打下基础。文中简单介绍了该系统的运行条件，数据结构和技术功能等。     

枣粮间作密度初探

枣粮间作是广大劳动人民的创举,是提高土地资源利用率,增加单位面积产量、提高产值的有效途径.为探讨枣粮间作中枣树栽植的合理密度,遵循"枣粮并重"的原则,从1999年6月开始,在枣粮间作集中分布区,实际调查了不同枣树密度下粮、枣产量及产值,并运用数学分析的方法,模拟出枣粮间作的最佳理论密度.     

Factors affecting forest growth and possible effects of climate change in the Taihang Mountains, northern China

To estimate the possible effects of site factors and climatechange on forest growth in the Taihang Mountains, northern China,we assessed the factors influencing forest growth by using forestinventory data from 712 forest sample plots. Meteorologicaldata from 77 meteorological stations in the region were usedto estimate temperature and precipitation at each site fromelevation and longitude. Analyses showed that temperature, aspect,precipitation and soil thickness all significantly influencedforest growing stock (FGS), i.e. stem volume. When temperaturerose, FGS was reduced, possibly because increasing temperatureincreased evapotranspiration. Precipitation had a positive effecton FGS. The effect of aspect on FGS was perfectly expressedas a cosine function, with south-west- and south-facing slopeshaving the lowest FGS and north-facing slopes having the highest.We developed multifactorial regression models to predict changesin FGS in the Taihang Mountains. Temperature, forest age, forestcover, soil thickness, precipitation and aspect were well relatedto FGS. The effects of a temperature decrease and a precipitationincrease on FGS would be 2.5–8 per cent per degree centigradeand 10 per cent per 100 mm, respectively. The combination oftemperature increase and precipitation changes under futureclimate change is likely to result in a decrease of FGS, thoughthis does not take account the effect of increasing CO₂. Wealso used multifactorial regression models to analyse the effectsof site factors on FGS of Pinus tabulaeformis Carr. and Robiniapseudoacacia L., two major species used in afforestation inthe Taihang Mountains. Although site factors had similar effectson FGS, diameter at breast height and tree height of both species,prediction accuracy (regression coefficient) was improved greatlywhen we treated the species separately.     

Expression of a scorpion toxin gene <Emphasis Type="Italic">BmKit</Emphasis> enhances the virulence of <Emphasis Type="Italic">Lecanicillium lecanii</Emphasis> against aphids

Lecanicillium lecanii has been developed as biopesticides and widely used in the biological control of several insects in agricultural practice. However, the poor efficacy has blocked its application. The genetic manipulation has been proved as a useful tool to improve the virulence of entomopathogenic fungus. In this study, a scorpion toxin gene (BmKit) from Buthus martensi was cloned and transferred into L. lecanii and then its resulting activity against cotton aphids (Aphis gossypii) was assessed. The results showed that the engineered strain BmKit-12 grew significantly quicker than WT in host insects. The median lethal concentration (LC₅₀) for BmKit-12 was 7.1-fold lower than that for WT, and the median survival time (LT₅₀) for BmKit-12 was reduced by 26.5 % compared with that for WT. Although the conidial yield was reduced by 31.4 % on insect cadavers, the mycelia growth, sporulation, and conidia germination of BmKit-12 on plates were not significantly different from WT. Considering the lower amount of mycelia for BmKit-12 in host insects in late growth stage (fungal sporulation stage), we think the expression of BmKit may not affect the capability of sporulation. In conclusion, the expression of BmKit gene can significantly enhance the pathogenicity of L. lecanii against cotton aphids in a relatively cost-effective way.     

树文化自信育大国工匠——少数民族地区高职旅游英语课程思政探索

指出了少数民族地区地处偏僻、地方经济相对落后,要实现“为国家和地方经济发展培养适应生产、建设、管理、服务第一线需要的数以百万计的应用型技术技能人才”的教育目标、助力脱贫攻坚,则践行立德树人的根本任务更为突出。因此,探索了高职旅游英语课程思政的有效路径,并从教师、教材、教法3个角度切入,提出了教师跨学科优化团队建设、教材融合地方少数民族特色研发、教法基于产出导向(POA)拓展教学时空等有效路径。     

食用菌工程训练课程线上线下混合教学模式探索

新冠疫情期间,线上教学发挥了非常重要的作用,后疫情时期线上、线下混合教学也已扎根各类课程的教学.该文以食用菌工程训练课程为例,从农业工程训练课程现状入手,探索了农业工程训练课程的线上、线下混合教学模式、课程内容组织和教学评价体系.