兴安落叶松天然林不同分化等级林木树干液流对综合环境因子的响应

[目的]以大兴安岭北部典型寒温带针叶林优势建群树种兴安落叶松为对象,分析不同分化等级林木树干液流对环境因子的综合响应,构建不同分化等级林木树干液流模型。[方法]利用热扩散式液流监测系统和通量塔的梯度气象系统连续监测树干液流及环境因子的变化。[结果]表明:1)观测期间,优势木具有较强的蒸腾能力,其平均液流密度分别为中等木和被压木的1.9倍、2.5倍。总体上,分化程度越高的林木日树干液流持续时间越长,液流密度峰值出现时间越早,液流密度的峰值也越高。2)利用主成分分析将降雨、净辐射、空气温度、空气湿度、风速、土壤温度、土壤含水量和水汽压亏缺降维为蒸发需求因子(EDI)、土壤水热因子和降水因子。EDI(与净辐射、温湿度、水汽压亏缺显著相关)是影响该地区林木树干液流的关键环境要素,其携带环境数据信息量的45%;土壤水热因子和降水因子分别携带20%和13%。3)各分化等级林木树干液流密度对EDI呈顺时针时滞,对净辐射和水汽压亏缺则分别呈逆时针、顺时针时滞,且EDI的时滞效应明显较小。不同分化等级林木液流密度对EDI和水汽压亏缺的时滞表现一致,对净辐射的时滞则以优势木最小。4)各分化等级林木树干液流密度对EDI的响应均符合"S"型模型,即液流升高到阈值后,不再随蒸发需求的增加而增大。模型中,中等木(0.458)和被压木(0.457)的过渡斜率略高于优势木(0.443),表明优势木树干液流对环境因子的敏感性略低。该模型对不同分化等级林木液流密度的模拟精度均在90%以上,考虑EDI的时滞效应或引入土壤水热因子、降水因子对模型精度的影响较小。[结论]兴安落叶松树干液流对综合环境因子存在较强的响应性,且在不同分化等级间存在差异;利用"S"模型和综合环境因子可有效估算不同分化等级兴安落叶松的树干液流。     

甘肃连城国家级自然保护区的植物组成及种子植物区系分析

甘肃连城国家级自然保护区地处黄土高原向青藏高原的过渡地带,其组成区内植被类型的植物物种较为丰富。据调查统计,连城自然保护区有植物109科、444属、1 397种,其中种子植物有82科、404属、1 338种。在种子植物中,单种科、属植物所占比重较大,反映出该保护区环境的复杂性和植物区系的年轻性。在其种子植物区系中属的地理成分复杂多样,与其他地区联系广泛,并具有过渡的特性,而在分布类型中以北温带成分占优势。     

不同杨树品系引种试验初报

对不同杨树品系的生长量、物候期、抗虫性和抗寒性进行分析比较。结果表明:9年生不同杨树品系单株材积差异极显著,超过平均材积的有‘欧美杨014’、‘111’、‘108’、‘中阳9’、‘F6’和‘中林299’;各品系物候期差异较大,以落叶盛期物候期差异幅度最大,最早与最晚相差22天。‘白城杨’从芽开放期到落叶期的生长期最短,为184天;‘欧美杨108’生长期最长,为202天;各品系除‘中林299’和‘荷兰3930’属于高感虫品系外,其他均为抗虫品系。后期物候期出现较晚的‘欧美杨108’、‘F6’和‘014’均遭受不同程度的冻害,‘欧美杨108’冻害较重。‘欧美杨111’和‘中阳9’无冻害且抗虫性较强,在辽宁省适宜地区具有良好的推广前景。     

清洗方式对两种叶类蔬菜保鲜效果的影响

以小白菜、小油菜两种叶菜为研究对象,采用整株、叶片分别浸洗和超声清洗方式,研究0 ℃、相对湿度85%~95%条件下清洗方式对其保鲜效果的影响,以无清洗整株叶菜作为对照。结果表明：叶片清洗处理组洗净率显著高于整株清洗,但贮藏5 d后黄化、腐烂现象较严重;小白菜清洗后易腐烂,但采用整株超声清洗的方式在贮藏第5天时失重率仅为0.77%,低于无清洗对照组,且无黄化、腐烂现象,采用整株浸洗的小油菜在贮藏第7天黄化指数最低,仅为2.2,且感官评分最高;建议清洗后小白菜和小油菜的商品期分别控制在5、7 d以内。     

Intranet信息安全工作中客户端的防护

本文从内网客户端的软件、硬件和安全意识几个方面阐述了Intranet信息安全工作的重心和防护措施.     

昆虫学专业课程教学的几点体会

论述了专业课教学中，使用多媒体教学的优势、备课的思想方式、课堂教学的方式以及教学与科研相结合在教学中的作用。     

Proteomics Identification of Differentially Expressed Proteins Relevant for Nicotine Synthesis in Flue-Cured Tobacco Roots Before and After Decapitation

Nicotine is a secondary substance synthesized in tobacco roots. In flue-cured tobacco planting, tobacco decapitation is an effective practice to promote nicotine biosynthesis by regulation of the redistribution of total nitrogen amounts. However, proteins relevant to nicotine synthesis in tobacco roots has not been identified and characterized yet. It is important to explore the regulation of nicotine biosynthesis in tobacco roots. To identify the proteins relevant to nicotine synthesis, the protein patterns in roots of flue-cured tobacco （cv. K326） before and after decapitation were analyzed. In the present study, the protein patterns in roots of flue-cured tobacco were analyzed by two-dimensional electrophoresis （2-DE）, and the differentially-expressed spots were identified by matrix assisted laser desorption ionization time of flight mass spectrometry （MALDI-TOF-MS）. Paired comparison of 2-DE maps revealed 26 spots of differentially-expressed proteins in roots before and after decapitation. Furthermore, nine differentially-expressed spots were identified. There were four proteins which were enzymes possibly involved in nicotine biosynthesis. In addition, the roles of the four enzymes in nicotine biosynthesis were discussed in a putative network. Our results would contribute to the understanding of the regulation pathway of nicotine biosynthesis and further to the molecular manipulation on the nicotine contents in flue-cured tobacco.     

一种优化的辣椒尖孢炭疽菌遗传转化体系

由辣椒尖孢炭疽菌(Colletotrichum acutatum)侵染引起的炭疽病是辣椒生产中最具有破坏性的真菌病害,严重影响辣椒的品质和产量。本研究以辣椒尖孢炭疽病菌HHDL02为对象,采用1 mol·L^-1 NH₄Cl 2%的酶裂解液裂解分生孢子萌发2 h的芽管,裂解2～3 h可以高效制备原生质体,结合PEG介导转化法成功将GFP基因导入,其转化菌株菌落形态、菌丝生长速率、分生孢子形态、孢子萌发、附着胞形成、产孢量和致病性与野生型菌株无明显差异,且后代荧光信号遗传稳定。PEG介导的原生质体转化适合辣椒尖孢炭疽菌遗传操作,有助于其致病机理的研究。     

甲氨基阿维菌素苯甲酸盐水分散粒剂对甜菜夜蛾的毒力及田间药效评价

室内测定了甲氨基阿维菌素苯甲酸盐水分散粒剂对甜菜夜蛾的毒力,结果表明其对甜菜夜蛾二龄幼虫的LC50为6．81mg／l。田间药效试验结果表明,2％的甲氨基阿维菌素苯甲酸盐水分散粒剂对甜菜夜蛾低龄幼虫具有良好防治效果,在用药量为93．25～112．5g／ha的情况下,防治效果达90％以上。     

Effect of Ganoderma lucidum spores on IL-1β and c-Fos in the brain tissue of epilepsy rats

AIM: To observe the influence of Ganoderma lucidum spores on the cytokine IL-1β and c-Fos in the brain tissue of epilepsy rats. METHODS: The IL-1β level was examined by radioimmunoassay and the c-Fos expression was measured by mmunohistochemical assay. RESULTS: Comparing the Ganoderma lucidum spores group with the epilepsy model group: c-Fos positive cell count in brain cortex and hippocampus in treatment group was obviously reduced. IL-1β level in brain tissue was also reduced obviously. CONCLUSION: Ganoderma lucidum spores effectively reduces cytokine IL-1β in brain tissue of epilepsy rats, improves the immunity dysfunction and plays a role in anti-epilepsy through suppressing c-Fos expression in epilepsy rats brain tissue and blocking of LRG.