Endophytic Bacteria Promote the Growth of Suaeda glauca in Saline-Alkali Stress:Regulation of Osmotic Pressure and Antioxidative Defense System

Endophytic bacteria are promising bacterial fertilizers to improve plant growth under adverse environment.For ecological remediation of coastal wetlands,it was necessary to investigate the effect and interaction of endophytes on halophytes under saline-alkali stress.In this study,an endophytic bacterium strain HK1 isolated from halophytes was selected to infect Suaeda glauca under pH(7 and 8)and salinity gradient(150,300 and 450mmolL^(-1)).Strain HK1 was identified as Pantoea ananatis and it had ability to fix nitrogen,dissolve inorganic phosphorus and produce indole-3-aceticacid(IAA).The results showed that strain HK1 could promote the growth of S.glauca seedings when the salinity was less than 300mmolL^(-1),in view of longer shoot length and heavier fresh weight.The infected plants could produce more proline to decrease the permeability of cells,which content increased by 26.2%–61.1%compared to the non-infected group.Moreover,the oxidative stress of infected plants was relieved with the malondialdehyde(MDA)content decreased by 16.8%–32.9%,and the peroxidase(POD)activity and catalase(CAT)activity increased by 100%–500%and 6.2%–71.4%,respectively.Statistical analysis revealed that increasing proline content and enhancing CAT and POD activities were the main pathways to alleviate saline-alkali stress by strain HK1 infection,and the latter might be more important.This study illustrated that endophytic bacteria could promote the growth of halophytes by regulation of osmotic substances and strengthening antioxidant activities.This finding would be helpful for the bioremediation of coastal soil.

Research Progress on the Growth-Promoting Effect of Plant Biostimulants on Crops

A Plant Biostimulant is any substance or microorganism applied to plants to enhance nutrition efficiency,abioticstress tolerance,and/or crop quality traits,regardless of its nutrient content.The application of Plant biostimulants(PBs)in production can reduce the application of traditional pesticides and chemical fertilizers and improvethe quality and yield of crops,which is conducive to the sustainable development of agriculture.An in-depthunderstanding of the mechanism and effect of various PBs is very important for how to apply PBs reasonablyand effectively in the practice of crop production.This paper summarizes the main classification of PBs;Thegrowth promotion mechanism of PBs was analyzed from four aspects:improving soil physical and chemical properties,enhancing crop nutrient absorption capacity,photosynthesis capacity,and abiotic stress tolerance;At thesame time,the effects of PBs application on seed germination,seedling vigor,crop yield,and quality were summarized;Finally,how to continue to explore and study the use and mechanism of PBs in the future is analyzedand prospected,to better guide the application of PBs in crop production in the future.

Improving school physical education to increase physical activity and promote healthy growth of Chinese school-aged children Time for action

Throughout its more than 5000-year history,China has a long tradition of encouraging active engagement in physical and sport activities.1,2This enduring tradition,however,has been facing some major headwinds as China continues to experience demographic and environmental changes related to aging,urbanization,and lifestyle shifts.3-5Mounting evidence indicates increasing levels of sedentary behaviors。

A novel apidaecin Api-PR19 synergizes with the gut microbial community to maintain intestinal health and promote growth performance of broilers

Background: Antibiotic growth promoters(AGPs) have been used as growth promoters to maintain animal intestinal health and improve feed efficiency in broilers by inhibiting pathogen proliferation. In view of the growing emergence of antibiotic-resistant pathogen strains and drug residue issues, novel treatments are increasingly required. This study aimed to compare two antimicrobial approaches for managing pathogen infection and maintaining animal intestinal health in broilers by supplying Apidaecin Api-PR19 and AGPs over 42 d of a feeding trial.Results: Compared with the broilers that were only fed a corn-soybean basal diet(CON group), supplementation with Api-PR19 and AGP(respectively named the ABP and AGP groups) both increased the feed conversion efficiency. When compared with the AGP group, Api-PR19 supplementation could significantly increase the organ index of the bursa of fabricius and subtype H9 antibody level in broiler chickens. Moreover, when compared with the CON group, the intestinal villus height, intestinal nutrient transport, and intestinal s Ig A content were all increased in the Api-PR19 group, while AGP supplementation was harmful to the intestinal villus height and intestinal nutrient transport. By assessing the antibacterial effect of Api-PR19 and antibiotics in vitro and in vivo, we found that Api-PR19 and antibiotics both inhibited the growth of pathogens, including Escherichia coli and Campylobacter jejuni. Furthermore, by using 16 S r RNA gene sequencing, the beneficial bacteria and microbiota in broilers were not disturbed but improved by apidaecin Api-PR19, including the genera of Eubacterium and Christensenella and the species of uncultured_Eubacterium_sp, Clostridium_asparagiforme, and uncultured_Christensenella_sp, which were positively related to improved intestinal development, absorption, and immune function.Conclusion: Apidaecin Api-PR19 treatment could combat pathogen infection and had little negative impact on beneficial bacteria in the gut compared to antibiotic treatment, subsequently improving intestinal development,absorption, and immune function.

Semaphorin 3A: from growth cone repellent to promoter of neuronal regeneration

Highlight Semaphorin 3A is a classically known axonal guidance cue that mediates axonal growth cone repulsion and collapse.Recent works,however,suggest that it may have the apparently diametrically opposite activity of promoting neuronal regeneration.

Utilizing the γ-Irradiated Sodium Alginate as a Plant Growth Promoter for Enhancing the Growth,Physiological Activities,and Alkaloids Production in Catharanthus roseus L.

Sodium alginate is a polysaccharide that is largely obtained from the brown algae （Sargassum sp.）.It has been used as a wonderful growth promoting substance in its depolymerized form for various plants.The aim of this study was to find out the effects of various concentrations of γ-irradiated sodium alginate （ISA）,viz.,deionized water （control,T0）,20 （T1）,40 （T2）,60 （T3）,80 （T4）,and 100 ppm （T5） on the agricultural performance of Catharanthus roseus L.（Rosea） in terms of growth attributes,photosynthesis,physiological activities,and alkaloid production.The present work revealed that ISA applied as leaf-sprays at concentrations from 20 to 100 ppm might improve growth,photosynthesis,physiological activities,and alkaloid production in C.roseus L.significantly.Of the various ISA concentrations,80 ppm proved to be the best one compared to other concentrations applied.

Promoter polymorphism of transforming growth factor-β1 gene and ulcerative colitis

AIM: To elucidate the possible difference in two promoter polymorphisms of the transforming growth factor-β1 (TGF-β1) gene (-800G > A, -509C > T) between ulcerative colitis (UC) patients and normal subjects.METHODS: A total of 155 patients with established ulcerative colitis and 139 normal subjects were selected as controls. Two single nucleotide polymorphisms within the promoter region of TGF-β1 gene (-509C > T and -800G > A) were genotyped using PCR-RFLP. RESULTS: There was a statistically significant difference in genotype and allele frequency distributions between UC patients and controls for the -800G > A polymorphism of the TGF-β1 gene (P < 0.05). The frequency of the TGF-β1 gene polymorphism at position -800 showed that the AA genotype and the allele A frequencies significantly differed between the patients and healthy controls (P < 0.05). At position -509, there was no statically significant difference in genotype and allele frequency between the patients and control subjects.CONCLUSION: The results of our study indicate that there is a significant difference in both allele and genotype frequency at position -800G > A of TGF-β1 gene promoter between Iranian patients with UC and normal subjects.

Analysis of SNPs in the Promoter Region of the Growth Hormone(GH) Gene in Mini-pigs

Single nucleotide polymorphisms(SNPs) of the growth hormone(GH) gene were investigated in six pig breeds,consisting of four mini-pig breeds(Wuzhishan,Bama,Xiang and Tibet pig),and two others(Dahlan and Landrace pig).Three pairs of primers for promoter regions of the GH gene were designed on the basis of the pig genomic sequence and SNPs were detected by the PCR-SSCP method.The results indicated three mutations in the 5’-flanking region.The analysis results showed that the frequencies of allele A and D in four mini-pig breeds were higher than that in other breeds at a locus within the 5’-flanking region(P【0.05).These results suggest that differences in body size may be associated with these SNPs of 5’-flanking region and amino acid mutation of the signal peptide of GH in these pig breeds.

<i>Tithonia diversifolia</i>Leaves and Stems Use as Substrate Amendment Promote the Growth of Plantain Vivoplants in the Nursery

Tithonia diversifolia is a year-round weed that decomposes rapidly after application as a soil amendment and it is more and more used in agriculture due to its numerous properties. The use of Tithonia diversifolia in the production of plantain vivoplants is a great opportunity for small holders’ farmers that cannot easily buy chemical inputs for yield improvement. All plant parts are used because of their richness in nutrients, mineral elements and phytochemicals without knowing which part is the most efficient. Tithonia diversifolia used as substrate amendment for plantain vivoplants production in nursery could promote their growth. This study aims to evaluate the effect of T. diversifolia leaves and stems as substrate amendment on plantain vivoplants growth promotion. The vivoplants were produced in substrates amended with T. diversifolia leaves, stems, combination of leaves and stems, and control without amendment. The vegetative growth parameters (number of shoots, height and diameter of shoots, area of shoots leaves) were assessed in sterilized substrate and unsterilized substrate conditions. T. diversifolia leaves and stems treatment increases the number of shoots, the height and the diameter of shoots as well as the area of shoots leaves compared to the control. T. diversifolia stems are the more efficient treatment, followed by the combination of T. diversifolia leaves and stems and finally the T. diversifolia leaves. They act as a biofertilizer promoting thus, the growth of plantain vivoplants in the nursery. All parts of Tithonia diversifolia can therefore be used by poor small holder farmers, as green manure for soil amendment in a green agriculture context.

Magnetic nanotechnology to study and promote axon growth

After injury of the central and peripheral nervous systems,functional recovery is impaired by axon regeneration failure.Various approaches for promoting axon growth have been attempted but their low efficacy has prevented them from being clinically applicable.

Biotransformation of Shrimp Wastes by Bacillus subtilis OKF04 and Evaluation of Growth Promoting Effect in Crop Planting

In this study,we proposed a reliable and sustainable technique for the clean utilization of shrimp wastes,which can yield a solid inoculant of Bacillus subtilis OKF04 containing micronutrients at low cost without the risk of contamination.Study of the culture conditions revealed that the head of shrimp Litopenaus vannamei and the wheat bran acted as suitable substrates for the growth of B.subtilis OKF04.With 60%initial moisture content,30℃culture temperature,and 5%inoculation amount,followed by 48 hours of fermentation and 0.5%soluble starch added during the drying process(50℃for 6h),a solid B.subtilis OKF04 inoculant with a spore amount of 2.4×10^(10)CFU g^(-1)and a high amino acid content was obtained.The solid B.subtilis OKF04 inoculant was applied to cultivate pakchoi under pot experiment.As the result,of adding to,the size of stems and leaves,nutritional composition,and physiological activity of pakchoi were significantly(P<0.05)enhanced by solid B.subtilis OKF04 inoculant.B.subtilis OKF04 also significantly(P<0.05)increased the soil’s nutrient content and improved its microbial composition.Furthermore,pakchoi cultivated with a low dose of solid B.subtilis OKF04 inoculant(0.05 g kg^(-1)soil)resulted in the best results.This study provides a new method for the preparation of microbial inoculants with solid waste shrimp heads.

垂穗披碱草根际促生菌的分离鉴定及促生作用研究

优良的根际生长促生菌(Plant growth-promoting rhizobacteria, PGPR)是生产优质微生物菌肥的重要物质基础。本研究以广布于青藏高原的垂穗披碱草(Campeiostachys nutans Griseb.)为材料,采用平板划线法分离其PGPR,探究菌株的促生特性,通过16S测序确定菌株的分类地位,并进行盆栽试验验证PGPR的促生效果。结果表明,从垂穗披碱草根际土筛选出14株促生特性优良的PGPR,其中,有11株兼具产IAA,ACC脱氨酶以及铁载体的能力。经16S rDNA鉴定,以假单胞菌属为优势菌属,6株属于假单胞菌属(Pseudomonas),2株属于芽孢杆菌属(Bacillus),2株属于葡萄球菌属(Staphylococcus),其他四株分别属于类节杆菌属(Paenarthrobacter)、微杆菌属(Microbacterium)、不动杆菌属(Acinetobacter)和考克氏菌属(Kocuria)。盆栽试验表明,接种14株菌株对多年生黑麦草具有良好的促生效果,并能够提高其光合效率。研究结果丰富了植物根际促生菌菌种资源库,为实现农业“绿色增产”提供优质菌肥种质资源。

地方保护政策对中国新能源汽车市场推广的影响分析

加快建设全国统一大市场对推动中国新能源汽车产业发展具有重要意义,而各地频发的地方保护现象却成为阻碍新能源汽车市场推广的主要因素。以2010—2021年中国28个省(市、区)新能源汽车推广数量的面板数据作为研究样本,分析了地方保护政策对新能源汽车市场规模和市场占比的影响,以及产品市场发育程度在其中的调节和门槛效应。研究结果表明,地方保护政策对新能源汽车市场规模扩大和市场占比提升均有显著的抑制作用,产品市场发育程度在该影响过程中具有调节性作用,地方保护政策对市场规模的作用受到产品市场发育程度单一门槛效应的影响,而对市场占比的作用则受双重门槛效应的影响,呈现出先促进后抑制的倒“U”型特征。进一步研究显示,地方保护政策通过加深能源市场分割阻碍了新能源汽车市场推广。区域异质性表明,东部地区的地方保护政策对新能源汽车市场推广有显著的抑制作用,而中西部地区的保护政策则有助于市场规模的扩大;在有新能源汽车上市企业母公司的地区,地方保护政策的抑制作用更为明显;而在没有此类企业的地区,其抑制作用相对较弱。研究结论为打破中国新能源汽车产业中的地方保护主义、推动产业可持续发展提供了决策参考。

PGPR调控植物响应逆境胁迫的作用机制

盐碱、干旱等非生物胁迫是限制植物生长和产量的重要环境因子。植物根际促生菌(PGPR)是一类定殖于植物根系的有益微生物,利用其生物学功能制成的生物菌剂具有低成本、高效和环保等优点,不仅可促进植物生长与作物产量,还能提高植物对非生物胁迫的耐受性。本研究对PGPR定义和种类、生物学功能及其在植物响应盐碱、干旱、高低温及重金属等非生物胁迫中的作用加以综述,并对其未来研究方向进行展望,以期为今后PGPR介导植物抗逆性的研究与生物菌剂的开发和应用提供理论支撑。

不同促生菌配合生长调节剂处理对滩涂稻田盐分变化、水稻产量及品质的影响

为了探明促生菌和生长调节剂对滩涂稻田盐分变化、水稻产量及稻米品质的影响,于2020年6—11月,在江苏南通沿海滩涂地区布置水稻种植试验,采用双因素裂区设计,主区为促生菌浸种处理,包括清水(CK)、如东促生菌(RD)和宁波促生菌(NB)浸种,副区为生长调节剂喷施处理,包括喷施清水(W)、碧护(0.136%赤·吲乙·芸苔)(T1)和复硝酚钠(T2)。结果表明,种稻过程中灌溉水盐度变化幅度为0.78~1.12 g·kg^(-1),CK、RD和NB处理水稻生长期间土壤盐分变化幅度为1.11~1.87 g·kg^(-1)。水稻产量在RD和NB下较CK分别增加了4.65%和1.83%;在T1和T2下较W分别增加了5.50%和1.05%;RD-T1下水稻产量较CK-W增加效果最好,达到11.66%(P<0.05),且每穗粒数和实粒数分别增加了13.45%和13.85%(P<0.05)。与CK相比,RD稻米糙米率、直链淀粉和蛋白质含量均显著降低,其他品质指标无显著差异。双因素分析结果表明,生长调节剂对穗长、每穗粒数、实粒数和产量均具有显著影响,促生菌对水稻千粒重具有显著影响,生长调节剂和促生菌仅对水稻千粒重具有显著互作效应。可见,促生菌结合生长调节剂处理对滩涂水稻增产具有明显效果,且生长调节剂主要提高了每穗粒数和实粒数,促生菌主要改善了滩涂水稻千粒重。本研究结果为探索适宜的农艺管理措施以达到滩涂水稻增产目的提供了技术参考。

一株旱稻联合固氮菌株的分离鉴定及促生作用

[目的]旱稻是一种重要的种质资源,对成熟期旱稻根系内生固氮菌进行筛选与鉴定,以获得对旱稻有较好促生作用的菌株。[方法]采用联合固氮固体培养基培养方法,从成熟期旱稻根系中分离出内生固氮菌,通过扩增固氮酶nifH基因和16S rRNA基因进行分子鉴定和系统进化分析生化指标测定和形态学鉴定;采用透明圈法进行溶磷、产铁载体能力验证;以褐球固氮菌为阳性对照,利用ELISA测定试剂盒测定菌株分泌固氮酶活性、1-氨基环丙烷-1-羧酸(ACC)脱氨酶,采用Salkowski比色法测定生长素(IAA)含量,并研究其生长特征。将分离的固氮菌株以1%浓度(约8×10~7CFU/mL)浸泡旱稻谷种进行催芽,研究其促生效果。[结果]分离的菌株URR45为固氮菌,属于嗜温型微生物,最适生长温度为32~50℃,最适pH为6.0~6.5,不耐盐。其分泌的固氮酶含量为220.15 U/L,ACC含量为898.69 ng/mL,生长素含量为14.91 mg/L,固氮酶含量和ACC含量显著高于对照组褐球固氮菌。该菌株能够利用葡萄糖、麦芽糖等碳源,属于发酵型细菌,具有水解明胶、溶磷和产铁载体特性。该菌株经16S rRNA基因测序后通过NCBI BLAST比对,鉴定为Herbaspirillum seropedicae,隶属于Pseudomonadota门、Betaproteobacteria纲、Burkholderiale目、Oxalobacteraceae科、Herbaspirillum属,革兰氏染色呈阴性。促生试验结果表明,在主根长度、侧根长度以及测根数方面均显著高于对照组。[结论]该菌株对旱稻幼苗具有一定的促生作用,在农业上产上可作为功能性内生固氮菌开发利用。

基于“去腐生肌”法探讨升白灵药纱条促进肛周脓肿术后创面愈合的动物实验研究

目的 观察升白灵药对肛周脓肿术后创面愈合的影响。方法 将40只SD大鼠分为空白组、模型组、雷夫诺尔组和升白灵药组,除空白组外其他三组用粪菌液造肛周脓肿模型,给药至大鼠创面完全愈合。观察大鼠创面愈合时间,第5天、10天、15天的闭合指数,创面第3天和第15天的白细胞水平,创面VEGF、b-FGF表达水平和炎症因子TNF-α、IL-6的表达水平。结果 升白灵药组和雷夫诺尔组大鼠创面完全愈合时间与模型组相比显著缩短(P<0.01),且升白灵组大鼠创面愈合时间短于雷夫诺尔组(P<0.01);升白灵药组和雷夫诺尔组大鼠创面第5天、10天、15天的闭合指数大于模型组(P<0.01),升白灵药组大鼠创面第5天、10天、15天的闭合指数均大于雷夫诺尔组(P<0.01);与空白组相比,3个造模组第3天白细胞计数均上升(P<0.01),与其余两组相比,升白灵药组白细胞上升更加显著(P<0.01);第15天雷夫诺尔组和升白灵药组大鼠白细胞计数低于模型组(P<0.01),与雷夫诺尔组相比,升白灵药组白细胞下降更加明显(P<0.01);升白灵药组大鼠背部创面组织VEGF的表达水平高于模型组和雷夫诺尔组(P<0.01);升白灵药组、雷夫诺尔组大鼠背部创面组织b-FGF的表达水平较模型组升高(P<0.01);升白灵药组b-FGF的表达水平较雷夫诺尔组升高(P<0.01);升白灵药组、雷夫诺尔组促炎因子IL-6、TNF-α的表达水平较模型组明显降低(P<0.01);升白灵药组大鼠背部创面组织促炎因子IL-6、TNF-α的表达水平较之雷夫诺尔组降低(P<0.01)。结论 以“去腐生肌”为遣方原则的升白灵药纱条能够通过调节炎症因子水平,上调VEGF、b-FGF表达促进肛周脓肿创面愈合。

饲料添加中药抗病促生长与替抗应用研究

重点回顾兽用中药抗病促生长的历史背景,对兽用中药饲料添加应用经验进行总结,提出兽用中药“替抗”应以饲料添加为主要应用方向。对农业农村部饲料药物添加剂品种、《饲料原料目录》、卫生部门发布的“食药物质”目录进行全面梳理,提出“药饲同源”品种名单,研究提出科学遴选和应用兽用中药“替抗”品种原则建议,在现有兽药国家标准和注册标准品种基础上,通过与“药饲同源”品种比对分析,筛选出21种“替抗”兽用中药制剂,为兽用抗菌药使用减量化提供参考。

基于主体性建构向度的扬长教育模式论析

人才培养是高等教育的核心使命,也是其存在的基础和目的。当下人才培养问题很大程度上源于学生主体性的缺失。高等教育改革应然要求复归人的主体性建构,考虑个体的多样性,最大限度地帮助其实现自由而全面发展的期许。扬长教育模式,本质上立足于学生个体差异,注重其自主探究、扬长发展。其主体性建构的价值功能可以从知识选择、伦理建构和目标惠及等多个维度进行审视,现实旨趣则体现在坚持以人为本、聚集因材施教和指向多样育才。实践进路的过程设计应立足于学校、教师、学生3个层面,着眼于人才培养、资源配置、质量评价等多个环节,指向于德育实施、教学改革、制度优化等多个方面。