植物根际促生菌促生机理研究

化肥与农药的使用虽能促进植物的生长发育,但剂量过大会造成成本上升、土壤质量下降、环境恶化等不良反应.近年来研究发现存在一类自生型细菌称为植物根际促生菌(Plant growth-promoting rhizobacteria,PGPR),能忍受或抵抗植物所遭受的不利环境,进而促进种子萌发和促进植物生长.文章从PGPR的促进植物吸收营养功能、植物生长调节功能、生物防治性能和环境修复功能4个方面阐述,旨在了解PGPR促进植物生长的原理,找出能改善植株抗逆性,缩短生长周期,促进植株更好更快繁殖的方法.     

植物他感作用在林业生产中的应用

不同植物或相同植物在生长过程中除为争夺阳光、空气、水分等而发生斗争外，还会发生植物之间的化学战，这就是植物的他感作用，即各类植物之间（包括微生物之间的生化作用），一种植物将其次生代谢物质释放到环境中，这些化学物质能抑制或促进其他植物生长或发芽的现象。植物他感作用可广泛应用于营林树种选择、林木病虫害防治及林业生产中，在提高林业效益，促进林业发展中起着重要的意义。     

腐植酸的作用机制及其在林业上的应用

腐殖酸是由动植物遗骸经过微生物分解转化以及地球化学过程衍变积累起来的一类成分复杂的天然有机物质,其在改良土壤理化性质、促进植物生长、增加农林产量等方面发挥着重要作用。文中综述了腐植酸的特性,根据现有的研究结果探讨腐植酸对土壤、植物的作用机制,解析腐植酸的功能。在此基础上,从促进树木生长、提高树木抗逆性、改良树木生长环境等几方面介绍腐植酸在林业上的应用价值和现状,并对腐植酸在林业上开发应用研究方向进行展望。     

树木菌根的应用

真菌有破坏的作用。但是有些真菌—菌根菌能够帮助高等植物生长,特别是对于贫瘠土壤上树木的生长,作用更为明显。林业工作者的任务之一是取得这种有益的真菌,在林业上充分应用,使它发挥应有的作用。高等植物的根部,除了与根瘤细菌共生以外,还可以与土壤中的真菌共生。许多真菌发育在高等值物(如树木)的根部表面,或伸入根的组织内部,与高等植物发生共生     

森林立地分类在林业调查设计中的应用

影响森林植物生长的主要因素是气候、水分、地质、阳光等,森林立地则是对森林林地的自然环境因素影响的作用力。随着我们林业的不断发展,森林立地分类工作在林业调查设计中起到了重大的作用。本文对森林立地分类工作进行详细的分析研究,主要包括分类的原则性、方法、系统分析、评价等。森林立地分类在林业调查设计中的应用,为林业发展起到了显著作用,充分利用林地有力的自然因素,为林地植物生长提供完善的自然环境,根据研究结果提出了笔者的一些意见和建议。     

PGPR菌剂及可溶性腐殖酸对经济果林生长的影响

PGPR接种剂和腐殖酸型肥料对于黄土高原的造林成活率和经济林木的产量都有一定的提高作用。它具有防病、促进生长、增产、改良土壤等多种作用，植物表面吸收后，根际分泌物对土壤微生物有很大的影响。对提高植物体内过氧化酶活性，增强植物体自我营养调节与生殖关系平衡具有明显效力，从而提高植物的抗逆性。     

PGPR接种对海榄雌幼苗抗寒性的影响

为研究PGPR接种对海榄雌幼苗抗寒性的影响,2015年11月1日—2016年3月2日(其中平均气温10℃的时间持续30 d),在广州对海榄雌幼苗进行了室外盆栽接种PGPR试验。试验结果表明,与未接菌对照组相比,低温胁迫下各PGPR处理组的苗高、地径、叶干重、茎干重、根干重和总干重均显著提高;接菌后,海榄雌幼苗的抗寒性在不同程度上有所增强,与对照组60%的死亡率相比,各处理组接菌苗的死亡率为10%～50%;且PGPR的混合接种比单一接种具有更好的促进植物生长和增强抗寒能力。     

植物促生根圈细菌诱导植物系统抗性的研究进展

该文简要回顾了植物根圈促生细菌(PGPR)能够诱导植物系统抗病性(ISR)这一领域的研究历史,对ISR作用机理、研究法则、研究内容及其它相关问题进行了总结探讨,并展望其未来的研究方向。     

红树林PGPR微胶囊菌剂的制备与应用

采用锐孔-凝固浴法,对红树林PGPR微胶囊菌剂的研制进行了探讨。加工制造出PGPR微胶囊菌剂的专用生产设备,并形成较完整的PGPR微胶囊菌剂生产工艺流程。红树林PGPR微胶囊菌剂兼具缓释长效和生物降解特性,应用前景较好。     

菌根真菌在林业研究中的应用

菌根是土壤真菌与植物根系形成的一种共生体，是森林生态系统中的重要组成部分，由于其特殊的结构和与林木共生的生态关系，在林业中被广泛研究与应用。该文分别从提高育种率、促进林木生长、增强林木抗逆性和生态环境修复4个方面总结了菌根真菌在林业中的作用及研究进展，旨在为菌根技术在林业中的应用提供理论支持。     

Water stress responses of two Mediterranean tree species influenced by native soil microorganisms and inoculation with a plant growth promoting rhizobacterium

Soil microorganisms, such as plant growth-promoting rhizobacteria (PGPR), play crucial roles in plant growth, but their influence on plant water relations remains poorly explored. We studied the effects of native soil microorganisms and inoculation with the PGPR strain Aur6 of Pseudomonas fluorescens on water stress responses of seedlings of the drought-avoiding Pinus halepensis Mill. and the drought-tolerant Quercus coccifera L. Plant growth, nutrient concentrations and physiology (maximum photochemical efficiency of photosystem II (PSII; F(v)/F(m)), electron transport rate (ETR), stomatal conductance (g(s)) and predawn shoot water potential (Psi(PD))) were measured in well-watered plants, and in plants under moderate or severe water stress. Inoculation with PGPR and native soil microorganisms improved tree growth, and their interactions had either additive or synergistic effects. Both F(v)/F(m) and ETR were significantly affected by PGPR and native soil microorganisms. Marked differences in g(s) and Psi(PD) were found between species, confirming that they differ in mechanisms of response to water stress. A complex tree species x treatment interactive response to drought was observed. In P. halepensis, F(v)/F(m) and ETR were enhanced by PGPR and native soil microorganisms under well-watered conditions, but the effects of PGPR on Psi(PD) and g(s) were negative during a period of water stress. In Q. coccifera, F(v)/F(m) and ETR were unaffected or even reduced by inoculation under well-watered conditions, whereas Psi(PD) and g(s) were increased by PGPR during a period of water stress. Our results indicate that microbial associates of roots can significantly influence the response of tree seedlings to drought, but the magnitude and sign of this effect seems to depend on the water-use strategy of the species.     

Pseudomonasaeruginosa strain PS1 enhances growth parameters of greengram [Vignaradiata (L.) Wilczek] in insecticide-stressed soils

Plant growth promoting rhizobacteria (PGPR) are known to increase growth and vigor of legumes in conventional cropping systems. Considering this as a basis, this study was aimed at identifying phosphate-solubilizing (PS) rhizobacterial strains expressing higher tolerance to insecticides, fipronil and pyriproxyfen, and synthesizing plant growth regulators even amid insecticide stress. The impact of selected rhizobacteria endowed with multitude of activities was investigated on greengram, grown in soils treated with different concentrations of insecticides. The fipronil and pyriproxyfen tolerant Pseudomonas aeruginosa strain PS1 produced plant growth promoting substances, both in the presence and absence of the insecticides. Both insecticides at recommended and higher rates, in general, had phytotoxic effects and decreased phytomass, symbiotic properties, nutrients uptake, and seed yield of greengram plants. Interestingly, P. aeruginosa PS1 even when used with all concentrations of the two insecticides significantly increased the measured parameters at 50 and 80 days after sowing, compared to the plants grown in soils treated with the same concentration of each insecticide but without inoculants. P. aeruginosa PS1 can be used as biofertilizer to augment the growth of greengram exposed to insecticide-stressed soils.     

金钱树的室内装饰和园林景观应用

金钱树（Zamioculcas zamiifolia）是原产非洲的常绿草本植物,具羽状复叶和地下块状茎,可在低光照下生长和耐干旱,有独特的观赏价值。它是优良的室内观叶植物,也可用于园林配景,配以不同盆器后可产生不同的观赏效果。大小不同的植株均可利用进行观赏美化。通过组合盆栽和水养盆栽可提高观赏性和应用范围。最后还介绍了金钱树室内管理要点。     

Variations in leaf functional traits among plant species grouped by growth and leaf types in Zhenjiang,China

Leaf functional traits are adaptations that enable plants to live under various environmental conditions. This study aims to determine the differences in leaf functional traits among plants grouped by growth habit, leaf life span, leaf lifestyle, leaf form, and origin. Specific leaf area (SLA) of perennial or evergreen species was lower than that of annual or deciduous species because longer-lived leaves of perennial or evergreen species require more investment in structural integrity and/or defense against disturbances, especially with any resource constraint. SLA of large individuals was lower than that of small individuals. The low SLA in large individuals can improve their response to changing light and water conditions because increasing plant height is advantageous for light competition, but it can also impose a cost in terms of structural support and water transport. Petioles of plants with compound leaves were significantly longer than those of simple leaves because branching is expensive in terms of gaining height. SLA of plants increased with increasing invasiveness accordingly, and SLA of invasive plants was higher than that of their native congeners because invasive plants should invest more biomass on leaf growth rather than leaf structures per unit area to achieve a higher growth rate. Overall, variation in leaf functional traits among different groups may play an adaptive role in the successful survival of plants under diverse environments because leaf functional traits can lead to pronounced effects on leaf function, especially the acquisition and use of light. Plant species with different growth and leaf traits balance resource acquisition and leaf construction to minimize trade-offs and achieve fitness advantages in their natural habitat.     

Progress in Research of Bacteria Fertilizer Strengthening Resistance of Plants

Bacteria fertilizer is used most widely among all kinds of microbial fertilizers. We summarize the research headway of bacteria fertilizer. It mainly focuses on bacteria fertilizer improving the stress resistance of plant. Then we can offer basis to research and exploit bacteria fertilizer. These bacteria include azotobacter, photosynthetic bacteria, Bacillus mucilaginosus siliceous, phosphorus bacteria, plant growth-promoting rhizobacteria(PGPR), effective microorganism(EM).     

Soil acidity, and the growth, biomass partitioning and leaf mineral composition of honeylocust (Gleditsia triacanthos L.) seedlings

Honeylocust seedlings (Gleditsia triacanthos L.) were grown in cylinders containing soil adjusted to pH 4, 5 or 6, and harvested every 10 days for 40 days for dry weight and leaf mineral analysis. Total weight of plants grown at pH 4 was less than that of plants grown at pH 5 or 6. Root weight accounted for a greater proportion of total weight in plants grown at pH 4 than in plants grown at pH 5 or 6. Root growth as a function of total plant growth was higher in plants grown at pH 4 than in plants grown at pH 5 or 6, whereas leaf growth as a function of total plant growth was less in plants grown at pH 4 than in plants grown at pH 5 or 6. However, the relationships between root biomass and root length and between leaf biomass and leaf area were the same in all treatments. An analysis of total leaf concentrations of Ca, P, K, Mg, Mn and Al indicated that Al accumulation in leaves was significantly related to a decrease in plant growth at pH 5. A leaf tissue aluminum concentration of 35 microg g(-1) was associated with toxicity symptoms and a 25% reduction in total plant weight.     

Influence of an indigenous European alder (Alnus glutinosa (L.) Gaertn) rhizobacterium (Bacillus pumilus) on the growth of alder and its rhizosphere microbial community structure in two soils

Europeanalder seedlings were inoculated with a suspension of the putative plant growthpromoting rhizobacterium (PGPR) Bacillus pumilus (CECT5105), or left non-inoculated (controls) in two different soils, and grownundercontrolled conditions. Soil A showed a thick texture, slightly acidic with ahigh mineral nitrogen content, while soil B showed a thin texture, basic andwith a lower nitrogen content. At each sampling time, over an 8-week period,shoot and root systems of the plants were measured, nodules counted, and shootand root length and surface were determined. In addition, changes in themicrobial rhizosphere structure were evaluated by the phospholipid fatty acid(PLFA) profile extracted directly from the rhizosphere soil. The increasesdetected in shoot surface were significant only in soil A, while the rootsystemwas affected in both soils. In soil A, inoculation with B.pumilus caused a perturbation that subsequently disappeared, whilethe rhizosphere community structure was seriously altered in soil B. Allbiometric parameters were enhanced to a greater extent in soil A, in which theinoculum did not alter the existing rhizosphere communities and nutrientavailability was better.