枯草芽孢杆菌PS-8对桔梗连作障碍土壤的修复及其促生作用

为探明用枯草芽孢杆菌PS-8研制一种新型连作障碍土壤改良剂的潜力,采用盆栽试验方法,向桔梗连作障碍土壤中施入不同比例(1%,2%,3%,4%)的枯草芽孢杆菌PS-8菌剂,于不同时期(施入菌剂后14,28,42,56 d)测定其对土壤微生物区系、酶活性、桔梗叶片MDA含量及对桔梗生长的影响。结果表明,施入不同量的枯草芽孢杆菌PS-8菌剂后,与同期对照相比,土壤中尖孢镰刀菌数量显著下降,细菌和放线菌数量显著上升,而总真菌数量显著下降,土壤中S-CAT活性显著低于同期对照,S-UE、蔗糖酶、磷酸酶活性显著高于同期对照,桔梗叶片MDA含量均明显低于同期对照。农艺性状测定也表明,枯草芽孢杆菌PS-8明显促进桔梗幼苗的株高和鲜重的增长。在不同比例菌剂的处理中,2%菌剂处理对上述各项指标的影响,不仅与对照相比具有显著差异,而且与其它三个处理之间也具有显著差异。综合分析可以得出,枯草芽孢杆菌PS-8能够改善桔梗连作障碍土壤的微生态环境,促进桔梗生长,对连作障碍土壤具有修复作用,可以进一步用来研制成桔梗大田生产中连作障碍土壤的改良剂。

Changes in chemical composition,structural and functional microbiome during alfalfa(Medicago sativa)ensilage with Lactobacillus plantarum PS-8

Improving silage production by adding exogenous microorganisms not only maximizes nutrient preservation,but also extends product shelf life.Herein,changes in the quality and quantity of Lactobacillus plantarum PS-8(PS-8)-inoculated alfalfa(Medicago sativa)during silage fermentation were monitored at d 0,7,14,and 28(inoculum dose of PS-8 was 1105 colony forming units[cfu]/g fresh weight;50 kg per bag;10 bags for each time point)by reconstructing metagenomic-assembled genomes(MAG)and Growth Rate InDex(GRiD).Our results showed that the exogenous starter bacterium,PS-8 inoculation,became the most dominating strain by d 7,and possibly played a highly active role throughout the fermentation process.The pH value of the silage decreased greatly,accompanied by the growth of acidproducing microorganisms namely PS-8,which inhibited the growth of harmful microorganisms like molds(4.18 vs.1.42 log cfu/g)and coliforms(4.95 vs.0.66 log most probable number[MPN]/g).The content of neutral detergent fiber(NDF)decreased significantly(41.6%vs.37.6%;dry matter basis).In addition,the abundance and diversity of genes coding microbial carbohydrate-active enzymes(CAZymes)increased significantly and desirably throughout the fermentation,particularly the genes responsible for degrading starch,arabino-xylan,and cellulose.Overall,our results showed that PS-8 was replicating rapidly and consistently during early-and mid-fermentation phases,promoting the growth of beneficial lactic acid bacteria and inhibiting undesirable microbes,ultimately improving the quality of silage.

佳多牌PS-15IV-8型频振式杀虫灯防治虫害效果研究

进行佳多牌PS-15IV-8型频振式杀虫灯防治虫害效果研究,结果表明:佳多牌PS-15IV-8型频振式杀虫灯对油菜露尾甲、小菜蛾、角野螟和小麦麦穗夜蛾的防治效果明显,尤其是诱虫灯下面的袋子里捕的麦穗夜蛾更明显地说明了诱虫灯防虫效果的有效性。佳多牌PS-15IV-8型频振式杀虫灯具有安全、实用、环保等优点,值得推广引用。

8-羟基喹啉螯合树脂对Pb^(2+)离子的吸附性能研究

研究了8-羟基喹啉螯合树脂(PS-HQ)在HAc-NaAc体系中对铅离子的吸附性能.结果表明,该树脂吸附Pb2+的最佳pH=4.0,吸附容量4.56 mg/g树脂.表观速率常数k288=1.52×10-4s-1,一次吸脱回收率达94.9%.吸附过程符合Langmuir和Freundlich模型.

阿尔茨海默病PS-1基因突变的研究

采用聚合酶链反应及基因测序技术探讨阿尔茨海默病(A lzhe im er病,AD)早老素-1(P resen ilin-1,PS-1)基因第3、4、5、8外显子的突变特点,对13例散发性A lzhe im er病(sporad ic A lzhe im er’s d isease,SAD)患者、12例血管性痴呆(vascu lar dem end ia,VD)患者及31名正常老年人的PS-1基因第3、4、5、8外显子片段进行扩增与序列分析.编号为SAD 5的患者PS-1基因第3外显子扩增片段上存在1个缺失突变位点,编号为SAD 3的患者PS-1基因第8外显子扩增片段的近3’端处发现2个插入突变位点.12例VD患者与31名正常老年人的PS-1基因第3、4、5、8外显子均未发现突变.实验结果表明,SAD患者PS-1基因中存在第3、第8外显子的突变.

8-羟基喹哪啶螯合树脂对Cr^(6+)的吸附性能研究

研究了8-羟基喹哪啶螯合树脂(PS-HQD)在HAc-NaAc体系中对铬离子的吸附性能。结果表明,该树脂吸附Cr6+的最佳pH为5.0,树脂吸附的平衡时间为8 h,吸附容量9.68 mg/g。表观速率常数k298=1.87×10-4s-1,一次洗脱回收率达94.3%。吸附过程符合Langmuir和Freundlich模型。

8-羟基喹啉螯合树脂吸附Cr^(6+)的研究

研究了8-羟基喹啉螯合树脂(PS-HQ)对溶液中Cr6+的吸附特性,研究内容包括pH、吸附温度等对吸附的影响。结果表明:PS-HQ能有效地除去水溶液中的Cr6+。在pH3.0~6.0的HAc-NaAc缓冲体系中,PS-HQ对溶液中的Cr6+均有较大的吸附能力,最佳的吸附酸度为pH4.0;吸附温度升高,吸附量增大,说明吸附是吸热过程;Freundlich和Langmuir等温吸附模型能较好地描述吸附过程;用硝酸、去离子水对吸附后的树脂进行再生试验,树脂的吸附能力可恢复到原来的93%~96%以上。8-羟基喹啉螯合树脂可作为理想的除Cr6+吸附的材料。