柳杉维管形成层及木质部区转录组序列及基因表达分析

柳杉是中国南方重要的针叶用材树种,具有树形高大,纹理直等特点,已广泛用于板材和建筑生产中,研究柳杉木材形成过程中维管形成层及木质部区转录组特征,为木材形成主要过程的分子机理,木材形成有关基因调控,培育优良材质的林木提供理论参考。本研究以柳杉形成层组织为材料,通过Illumina Hiseq测序平台对4个不同发育阶段的柳杉维管形成层进行转录组测序;对Unigene进行了蛋白功能注释、分类及KEGG代谢通路分析等。测序数据参照无参转录组测序流程进行分析,一共产生105.9 Gb的数据,过滤后Clean reads均达到90%以上。Clean reads经Trinity软件进行组装,一共产生64 969个Unigene,对Unigene进行拼接,拼接后的Contigs序列有29 381条、Singletons有35 588条,总长度为83 003 836 bp。将Unigen与七大功能数据库(NR, NT, GO, COG, KEGG, Swissprot, Interpro)进行比对,共有42 836个Unigene得到注释,占总Unigene的66.05%。GO注释共有89 644个转录本得到注释。对GO注释转录本进行分类,其中有38 432个转录本(42.87%)注释为生物过程,有32 749个转录本(36.53%)注释为细胞组分,有18 463个转录本(20.6%)注释为分子功能。KEGG注释有31 580个Unigene得到注释。分为6大类为:细胞代谢过程、环境信息处理、遗传信息处理、人类疾病、代谢作用、生物体系统。其中代谢作用涉及的Unigene最多达18 580个,占KEGG总注释Unigene的58.83%。另有37 762个Unigene得到COG注释,被分为25类,其中注释数目最多的类型是仅预测一般功能的Unigene,占总数的16.9%;其次是转录,比例为8.8%;再次是复制、重组及修复,占总数的7.8%。本研究最后分析了可能参与木材形成重要功能基因,为探讨木材发育的分子机制及进行重要功能基因的挖掘提供了提供了依据。     

玉米旅欧群体评价及利用潜势分析

通过向玉米辽旅群体中导入血缘相近、脱水速率快的9份欧美种质,构建成含有不同比例欧美种质的3份旅欧群体,能显著改善收获时含水量、出籽率、生育期、穗粗和穗行数等重要性状,且保持原始群体优良的产量一般配合力,显著提高出籽率、穗长和行粒数的一般配合力。杂种优势分析结果表明,旅欧群体所配制的组合有效提升出籽率、收获时含水量、生育期和其他穗部性状的杂种优势,与塘四平头类群的杂优模式存在极高的产量应用潜力,为改良本土种质资源适宜机械化收获和探索欧美种质新的杂优模式奠定基础。     

酵母及藻类对褶皱臂尾轮虫培养效果的比较研究

采用种群累积培养法研究了两种酵母、两种藻类对褶皱臂尾轮虫的最适投喂密度。结果表明 ,这四种饵料对褶皱臂尾轮虫的最适投喂密度 (× 10 6cell·ml-1)分别是 :干酵母 ,15 ;鲜酵母 ,5 ;微绿球藻 ,4 5 ;三角褐指藻 ,2 0。同时 ,在最适密度下比较了这四种饵料对轮虫的培养效果。结果表明 ,四种饵料对轮虫的培养效果以微绿球藻为最优 ,其它依次为三角褐指藻 ,鲜酵母 ,干酵母。实验结果显示 ,褶皱臂尾轮虫批量培养及至工厂化培养的首选饵料是微绿球藻和三角褐指藻     

Physiological metabolism of Haliotis discus hannai Ino under different light qualities and cycles

The goal of this experiment was to examine the effects of different light qualities (red, white, blue) and cycles (12L:12D, 8L:16D, 4L:20D, 0L:24D, 16L:8D) on the survival, growth, metabolism and antioxidant defence system of Haliotis discus hannai Ino. Under red and white light at 4L:20D, the body weight‐specific growth rate of abalones was significantly higher than that of the 0L:24D group (P < 0.05). At 16L:8D, succinate dehydrogenase activity decreased and lactate dehydrogenase and alanine aminotransferase activity and the lactic acid content significantly rose (P < 0.05) in the red and white light groups. Under blue light, reactive oxygen species and malondialdehyde content for each light cycle were significantly higher than those of the red and white groups (P < 0.05). Under blue, white and red light, total antioxidant capacity (T‐AOC), superoxide dismutase (SOD) activity, glutathione peroxidase (GP_X) activity and reduced glutathione (GSH) content gradually rose with increased duration of light exposure. Under red light, significant differences in these parameters were detected between the 4L:20D and 16L:8D groups (P < 0.05). Under blue and white light at 16L:8D, values of T‐AOC, SOD, GP_X activity and GSH content were significantly lower than those of the 12L:12D group (P < 0.05). Overall, these results indicate that red light at light cycles of 4L:20D and 8L:16D is optimal for the culture and production of H. discus hannai, as these conditions promoted food intake, growth and health maintenance as well as normal physiological metabolism of the organism.     

Effect of humic acid on the sedimentation and transport of nanoparticles silica in water-saturated porous media

Journal of Soils and Sediments - Nano silicon particles (nSiO2) is one of the most widely used industrial engineered nanomaterials (ENMs). The extensive applications of nSiO2 may pose potential...     

马铃薯细菌多样性解析及促生高产 IAA菌株的筛选

采用 3种不同的培养基从马铃薯根际土壤和叶片中共分离出 78株细菌,优势菌属是 Pantoea,占菌株总数的 55.13%。马铃薯根际土采用 R2A培养基(27株优势菌,13个菌属)分离的细菌多样性相对较好,阿须贝培养基(31株优势菌,9个菌属)次之,土壤浸提液培养基(1株优势菌,1个菌属)最少;马铃薯叶片内生菌用阿须贝培养基(19株优势菌,3个菌属)分离的细菌多样性较差。采用 Salkowski比色液显色法定量测定菌株产 IAA能力,结果表明有 58株细菌具有分泌 IAA的能力,占测定菌株总数的 74.36%,从马铃薯根际土(42株优势菌,13个菌属)筛选的产 IAA菌数量及细菌多样性均高于马铃薯叶片内生菌(16株优势菌,2个菌属)。根据菌株产IAA能力强弱和分离部位及分离培养基的差异,选择 7株产 IAA菌进行促生特性和马铃薯盆栽幼苗促生能力等研究,结果显示:有 6株产 IAA菌具有 ACC脱氨酶能力,1株产 IAA菌具有溶解无机磷能力,2株产 IAA菌具有溶解有机磷能力;两轮温室促生实验结果显示,菌株 Pantoeasp.MLS-34-25对马铃薯幼苗具有明显的促生作用,是生产微生物肥料的潜在菌种。     

城镇街道绿化景观设计初探

随着人们生活水平的不断提高,与此相应地对城镇街道绿化景观也提出了越来越高的要求。城镇街道绿化景观不仅是城市生态景观的重要组成部分之一,更是一个城市改善居民居住环境的重要途径。它不仅改善了城市环境,美化了城市形象,更能够彰显城市的文化内涵,对整个城市宜居水平产生着极其重要的影响。没有良好的城镇街道绿化景观,就没有良好的城市生态环境。基于此,试图就城镇街道绿化景观设计展开初步探讨研究,以供参考借鉴。     

铅胁迫对澳洲坚果幼苗生长及生理特性的影响

为探究澳洲坚果（Macadamia integrifolia）对土壤铅胁迫的耐受性,以3年生澳洲坚果实生苗为材料,研究不同浓度铅处理下（0、200、400、800、1 200、1 600和2 000 mg/kg）澳洲坚果幼苗生长及生理特性的变化。结果表明,除地径增量和可溶性糖含量外,铅浓度对澳洲坚果幼苗生长及生理特性均影响极显著。随铅浓度升高,幼苗株高和地径增量、叶绿素含量、可溶性蛋白和游离脯氨酸含量及SOD和POD活性均呈先升后降的趋势;可溶性糖含量呈先降后升的趋势;MDA含量逐渐上升。澳洲坚果幼苗对1 200 mg/kg以下的铅胁迫有一定抗性;1 200 mg/kg以上会对其造成毒害,抑制其生长。     

云斑尖塘鳢♀×线纹尖塘鳢♂杂交育种的初步研究

利用从国外引进的云斑、线纹尖塘鳢的自繁后代,经过强化培育、性腺促熟后,2009年5-9月开展人工杂交试验。试验结果:孵化水温28~30℃时,云斑尖塘鳢♀×线纹尖塘鳢♂孵化时间68h,受精率为90.0%,孵化率为83.6%,培苗出苗率为60.51%,研究证明尖塘鳢属种间杂交可以成功。     

Effect of LED light quality on the phototaxis and locomotion behaviour of Haliotis discus hannai

Abalones were reared in a laboratory to determine the percentage response rate, response time, average crawling speed and the time taken to recover an upright posture under nine light‐emitting diode light quality treatments (red, orange, yellow, green, cyan, blue, purple, white and grey) and a dark environment. Animals were placed in the centre of an experimental device, and the tropism of each animal was continuously monitored by video. The highest percentage response rate (80% in dark adapted abalones, 60% in light adapted abalones) was observed in the dark environment, followed by red and orange light (27% and 30% in dark adapted abalones, respectively, 22% and 24% in light adapted abalones). Two induction materials (substrate and brown algae Laminaria japonica) were used to assess the effect of light quality on the tropism of abalones, with the highest percentage response rate (76% in the L. japonica treatment, 22% in the substrate treatment) also observed in the dark environment, followed by red and orange light (both 25% in the L. japonica treatment, and 26% and 32%, respectively, in the substrate treatment). The tropism order of the abalones under dark, red, orange and yellow light was as follows: dark > orange > red, yellow, but fewer abalones chose to stay in blue, green, cyan and purple light. The response time (about 700 s) in the dark environment was significantly longer than for the other light quality treatments. Compared with the average crawling speed in the other light quality treatments, abalones were relatively slower (about 3.8 mm s^?1) in red and orange light, and the dark environment. The mean time required for the recovery of an upright posture in red light and the dark environment was longer than in the other light quality treatments, with the average recovery time reaching a maximum of 60 s in the dark environment. The results demonstrate the phototaxis and locomotion behaviour of abalones, as well as confirming the necessity of a dark, orange or red environment for their management and aquaculture.