腐植酸促进植物生长的机理研究进展

【目的】腐植酸在我国农业生产中发挥了重要作用,许多研究证实,腐植酸具有促进植物生长的功能,本文从腐植酸刺激植物根系生长、调控土壤与肥料养分转化及肥料利用率和影响土壤微生物和酶活性方面,系统总结了国内外施用腐植酸促进植物生长的途径,阐述了腐植酸对植物生长促进作用的机理,旨在梳理腐植酸促进植物生长机理的研究现状,为腐植酸的进一步研究和应用提供参考依据。[主要进展]1）腐植酸能够对植物产生类似生物刺激素的效应。它能够提高植物根系H+-ATP酶等的活性、刺激植物根伸长和侧根生长点的增加,从而增加根系活力及植物根系与土壤养分的接触面积,增加植物对养分的吸收;2）逆境胁迫下,腐植酸能够通过调节植物体内的新陈代谢并改善植物生长环境,缓解甚至消除逆境胁迫对植物的伤害,从而促进植物生长;3）腐植酸能够通过与氮素、磷素和钾素发生结合效应,与磷酸盐产生竞争效应和对钾离子的吸附作用固持与活化土壤与肥料中的养分,提高土壤肥料有效性和缓释性能,提高肥料利用率,从而促进植物生长;4）腐植酸还能够影响土壤中与养分转化相关的酶活性和微生物群落结构及数量,在活化养分的同时,保蓄养分,降低养分的损失,为植物生长保障持久的养分供应;5）腐植酸对植物生长的促进效应受腐植酸结构特征、添加量和供试植物种类等因素的影响。[建议与展望]由于技术手段的限制和研究技术的差异,人们对腐植酸促进植物生长机理的认识还不够系统和深入,因此,腐植酸的基本特征、影响腐植酸作用的主控因子、土壤-植物系统中腐植酸促进植物生长的主要途径和腐植酸对土壤功能性微生物等的影响都将成为未来研究的重要方向。     

复合微生物制剂对重茬草莓生长及产量品质的影响研究

试验研究了复合微生物制剂对重茬草莓植株生长及产量品质的影响。结果表明,复合微生物制剂对重茬未消毒土壤的草莓黄萎病防效达76.9%~84.6%。无论土壤是否消毒,复合微生物制剂均可提高草莓叶片的光合速率和叶绿素含量,促进草莓植株的生长,使物候期提前;显著提高草莓果实维生素C和可溶性糖的含量,改善果实品质和风味;草莓增产14.21%~16.20%。同时复合微生物制剂还可以改善土壤的理化性状,提高土壤肥力。     

微生物源的植物生长促进剂研究的新进展

本文综述了近几年国内外应用于生态农业的微生物源的植物生长促进剂的研究进展。涉及微生物制剂的种类、作用机理、剂型及其展望和发展趋势，为正确使用和进一步开发这类微生物制剂提供一定的理论依据。     

PG微生物制剂对棉花的增产效果

ＰＧ制剂作为一种新型微生物制剂－土壤磷活化剂，经田间小区试验证明，ＰＧ微生物制剂拌种用量４５０￣１５００ｍｌ／ｈｍ＾２对棉花都有增产作用，以１５００ｍｌ／ｈｍ＾２用量效果最佳，达极显著水平。     

微生物源的植物生长促进剂研究的新进展

本文综述了近几年国内外应用于生态农业的微生物源的植物生长促进剂的研究进展。涉及微生物制剂的种类、作用机理、剂型及其展望和发展趋势,为正确使用和进一步开发这类微生物制剂提供一定的理论依据。     

植物钙素营养机理研究进展

本文综述了近三十年来植物钙素营养机理的研究进展，内容包括细胞中钙的定位及其与超微结构的关系；细胞水平上钙的吸收与运输机制；钙对酶活性的调控机制，钙与植物激素的作用机理，植物个体水平上钙的吸收运输和分配，钙与其它营养元素的相互作用，植物钙营养遗传特性等，文中评述了当前有关钙营养的机理或假说，并提出了今后加强研究的问题。     

土壤微生物在促进植物生长方面的作用

土壤微生物与植物的根系形成一个稳定的动态系统,在这个系统中它们之间相互作用,相互影响。植物的根系为土壤微生物提供养分,土壤微生物反过来也促进了植物根系的发育,从而促进了植物的生长,从而促进了植物的生长。本文就土壤微生物生长特性,从7个方面阐述了土壤微生物对植物的促进作用。     

微生物制剂“绿源生”对黄瓜产量的影响

用“绿源生”微生物制剂叶面3次喷洒,比较大棚种植的3个品种黄瓜的增产效果。结果表明,“绿源生”能明显降低黄瓜的发病率,提高优质瓜率,增产率达20．0％-25．2％,经济效益显著。“绿源生”和NEB对黄瓜的增产效果差异不显著。     

植物微生态学与植物微生态制剂的应用

论述了微生态学引起微生物学的观念革命及生态制剂的崛起,植物微生态学概念及形成过程,以益微为例阐述了植物微生态制剂的概念与筛选、作用机理及性能特点、微生态学与持续农业（生态农业）的关系等。     

近期激光对植物生长调节效应的研究进展

分析了激光对植物生长调节效应的研究进展,发现研究明显具有以下特点:早期研究主要集中在激光预处理种子对种子萌发、幼苗生长发育、生理生化效应的影响以及激光处理机制的初步讨论;近年来的研究集中于激光处理对环境胁迫下植物生理生化效应影响,环境胁迫因子涉及增强UV-B辐射、干旱与冷冻,其中多数研究集中于激光对增强UV-B辐射下植物生理生化效应的影响,发现激光能增强植物抗UV-B辐射损伤,提高植物抗干旱逆境及抗冷冻能力,并对其作用机理及机制进行了探讨。今后可围绕全球生态环境变化背景下,激光处理对植物生理生化效应的影响进行研究,并深入研究激光影响的分子生物学机制机理。     

水稻中生长素作用的分子机理研究进展

水稻的生长与发育是受多个植物激素协同调控的,其中认识最早和研究最深的是生长素。随着分子技术的进步,研究生长素的作用机制已经深入到细胞和基因水平,包括生长素的代谢、运输、信号感知和传导,并且生长素的信号传导在水稻生长发育过程中与其他激素相互交叉、协调作用。研究生长素的作用机制对植物生长发育具有重要意义。     

PLANT GROWTH PROMOTING RHIZOBACTERIA INCREASE GROWTH,YIELD AND NITROGEN FIXATION IN PHASEOLUS VULGARIS

Nitrogen (N) fixation by legume-Rhizobium symbiosis is important to agricultural productivity and is therefore of great economic interest. Growing evidence indicates that soil beneficial bacteria can positively affect symbiotic performance of rhizobia. The effect of co-inoculation with plant growth-promoting rhizobacteria (PGPR) and Rhizobium, on nodulation, nitrogen fixation, and yield of common bean (Phaseolus vulgaris L.) cultivars was investigated in two consecutive years under field conditions. The PGPR strains Pseudomonas fluorescens P-93 and Azospirillum lipoferum S-21 as well as two highly effective Rhizobium strains were used in this study. Common bean seeds of three cultivars were inoculated with Rhizobium singly or in a combination with PGPR to evaluate their effect on nodulation and nitrogen fixation. A significant variation of plant growth in response to inoculation with Rhizobium strains was observed. Treatment with PGPR significantly increased nodule number and dry weight, shoot dry weight, amount of nitrogen fixed as well as seed yield and protein content. Co-inoculation with Rhizobium and PGPR demonstrated a significant increase in the proportion of nitrogen derived from atmosphere. These results indicate that PGPR strains have potential to enhance the symbiotic potential of rhizobia.     

RESPONSE OF MAIZE GROWN IN AN ALFISOL OF SRI LANKA TO INOCULANTS OF PLANT GROWTH PROMOTING RHIZOBACTERIA

Field experiments were conducted to assess the ability of rhizobacterial inoculants to enhance growth and yield of maize. Performances of two phosphorus (P)-solubilizing bacteria in combination with a fertilizer mixture containing rock phosphate and triple super phosphate (PFM), and five diazotrophs combining either with 150 kg or 100 kg nitrogen (N) ha^?1 supplied as urea were compared with non-inoculated-fertilized controls. Shoot P and N and soil available P and N contents were assessed and shoot biomass and ear weights were recorded at harvest. Pseudomonas cepacia resulted in significantly higher available P (51 mg P kg^?1 soil), P accumulation (3.6 g kg^?1 dry matter) and 13% increase in shoot biomass over control. Azospirillum sp. and dual inoculant comprising Enterobacter agglomerans + Agrobacterium radiobacter led to significantly higher available N (74–94 mg kg^?1 soil) and 19 to 26% increase in shoot biomass over the control. However, inoculants did not increase the yield significantly.     

植物生长调节剂在植物体细胞胚发生中的应用

合理应用植物生长调节剂是成功诱导体细胞胚的决定因素,也是影响体细胞胚高频率发生的主要因素。本文从生长素类、细胞分裂素类、赤霉素、脱落酸以及各类植物生长调节剂间组合使用等几个方面综述了外源植物生长调节剂在体细胞胚发生中的应用进展,为植物体细胞胚的诱导提供了一定的参考价值。     

EFFECTS OF PLANT GROWTH PROMOTING BACTERIA ON YIELD,GROWTH, LEAF WATER CONTENT,MEMBRANE PERMEABILITY,AND IONIC COMPOSITION OF STRAWBERRY UNDER SALINE CONDITIONS

Plant growth promoting effects of Bacillus subtilis EY2, Bacillus atrophaeus EY6, Bacillus spharicus GC subgroup B EY30, Staphylococcus kloosii EY37 and Kocuria erythromyxa EY43 were tested on strawberry cv. ‘Fern’ in terms of fruit yield, growth, chlorophyll reading value, leaf relative water content (LRWC), membrane permeability and ionic composition of leaves and roots under saline conditions. Compared with 0 mM sodium chloride (NaCl) treatment, the average decrease of yield and LRWC were 51.6% and 21.0%, respectively, when 35 mM NaCl was applied. However, EY30, EY37, and EY43 treatments under saline condition (35 mM NaCl) significantly increased fruit yield (54.4%, 51.7% and 94.9%) compared with 35 mM NaCl treatment without plant growth promoting bacteria (PGPB). The LRWC increased from 72.0% in 35 mM NaCl treatment to 88.4%, 86.6%, 84.2%, 83.5%, and 86.2% by EY2, EY6, EY30, EY37, and EY43 applications, respectively. The lowest membrane permeability among the bacterial strains was obtained from EY37 treatment (37) while it was 33 and 58 in 0 mM NaCl and 35 mM NaCl treatments, respectively. The concentration of all plant tissue nutrients investigated [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] with the exception of root phosphorus (P) and Mg concentration significantly decreased with 35 mM salt treatment. Nitrogen content of leaves varied between 3.04 and 3.14% in bacterial treatments under saline conditions while it was 2.71% in 35 mM NaCl treatment. In contrast sodium (Na) and chloride (Cl) of leaves and Cl content of roots were significantly decreased by root inoculation with all bacterial treatments in comparison to 35 mM NaCl treatment with no inoculation. Treatment with Bacillus EY30, Staphylococcus EY37 and Kocuria EY43 to strawberry plants can ameliorative the deleterious effect of salt stress on fruit yield, growth and nutrition. These results demonstrate that PGPB treatment could be offer an economic and simple means to increased plant resistance for salinity stress.     

航天诱变对须苞石竹种子和SP1代植株生长的影响

利用我国第21颗返回式卫星搭载须苞石竹种子,返回地面后进行种植,并观测种子活力、出苗率,植株生长特性、叶绿素含量等。结果表明：航天搭载造成须苞石竹种子活力和出苗率显著下降;株高显著变矮,花茎长度显著变短,小花花径花茎显著变大;叶宽、叶绿素a含量和叶绿素a/b有减小的趋势,冠幅和小花数有增大趋势。     

海涂海水灌溉对鲁梅克斯植物生长的影响

为高效持续利用海水与滨海盐土资源,缓解海水养殖废水直接排放对海洋的污染,课题组从1995年开始,收集、引进和筛选了一些具有经济开发前景的耐盐植物,对其生物学、生态学特性进行了研究[1],并在我国海南乐东、江苏大丰、山东莱州三个典型气候带海涂进行海水灌溉试验,探索海水灌溉对耐盐植物生长发育、滨海盐土演变的影响及其对海水养殖废水的净化能力.本文仅就山东莱州田间小区海水灌溉鲁梅克斯(Rumex patientiax R. Tianschanicus, cv. Rumex K-1)的试验结果进行讨论.     

无机磷对植物叶片光合作用的影响及其机理的研究进展

本文综述了无机磷（Pi）在叶片细胞中的分布、Pi对光合作用的影响及其机理的研究概况。缺磷植株叶片光合速率的下降，主要是阻碍了1，5-二磷酸核酮糖（RuBP）的再生。在源库反馈调节中，Pi起重要作用。     

非豆科植物固氮菌-Frankia的基因组研究进展

弗兰克氏菌(Frankia)能够与大约25个属的非豆科植物共生进行结瘤固氮,在生态系统中具有重要意义。本文对Frankia的基因组学研究进展进行了综述,包括Frankia基因组的结构、功能及其表达特点,同时比较了来源于不同菌株的固氮基因的差异,并提出今后的发展趋势。