胶质芽孢杆菌与苜蓿根瘤菌双接种对排土场紫花苜蓿生长和土壤性质的影响

为了明确胶质芽孢杆菌和苜蓿根瘤菌在矿区排土场复垦中的协同作用,以矿区排土场土壤作为基质进行盆栽试验,设置两菌单接种处理、双接种处理及对照,其中胶质芽孢杆菌和苜蓿根瘤菌用量分别为1.50%和0.25%,测定紫花苜蓿产量指标、叶片生理指标、土壤速效养分含量和土壤微生物指标。结果表明,接种胶质芽孢杆菌和苜蓿根瘤菌的各处理均能显著提高紫花苜蓿的产量指标,其中以双接种处理效果最优,将生物量和结瘤量分别比对照显著提高110.27%和124.32%;在生理指标方面,双接种处理效果低于单接种处理,未表现出协同作用;在土壤养分和微生物性质方面,单接种胶质芽孢杆菌仅显著提高土壤速效钾含量,单接种苜蓿根瘤菌对大部分指标均有显著效果,而双接种处理效果最佳,土壤碱解氮、速效钾含量比对照分别显著提高94.14%和84.55%,土壤微生物指标MBC含量、呼吸强度、蔗糖酶、脲酶、磷酸酶、过氧化氢酶活性比对照分别显著提高204.02%,65.86%,212.32%,91.87%,30.57%,51.87%。双接种处理对紫花苜蓿产量指标、养分和微生物指标表现出显著的协同作用。因此,1.50%用量胶质芽孢杆菌和0.25%用量苜蓿根瘤菌双接种能够有效提高排土场土壤的复垦效果,具有协同作用,可以作为矿区排土场复垦的高效方法。     

固氮球形芽孢杆菌与巨大芽孢杆菌的混合增效作用

球形芽孢杆菌Bs7与巨大芽孢杆菌Bm1 0 1混合培养时具有固氮增效作用。稀释 40 0倍的巨大芽孢杆菌的无菌上清液与球形芽孢杆菌共培养 ,同样能增强后者的固氮活性。Bs7(pAB5 76 )在纯培养时的nifA表达活性为 6 849 5Miller单位 ,与巨大芽孢杆菌上清培养液进行混合培养时的表达活性为 75 0 0 4Miller单位。上述结果表明 :某些微量非碳源的活性分泌物和某些固氮调节基因可能在固氮增效作用中起重要作用。在与水稻联合培养条件下 ,混合接种球形芽孢杆菌与巨大芽孢杆菌可以提高固氮菌在水稻根表的定殖能力     

接种根瘤菌对鸡骨草幼苗生长、结瘤和固氮能力的影响

用来自不同产地的鸡骨草根瘤菌接种盆栽幼苗,室内培养70 d后,测定植株生长和结瘤情况及植株含氮量。结果表明,接种根瘤菌对鸡骨草的株高、植株生物量、氮素相对积累量和固氮效率有明显的促进作用;不同来源的根瘤菌对鸡骨草生长和固氮的影响不同,来自玉林的根瘤菌菌株有较高的固氮效率。接种根瘤菌能促进鸡骨草生长,增加氮素累积,从而可以减少氮肥的使用,有利于充分发挥生物固氮的作用来提高原料药材的质量。     

土壤中大豆根瘤菌之间竞争结瘤的研究——Ⅲ.接种菌量对大豆生长的影响

本文研究了大豆根瘸菌PRC005的接菌量对大豆生长的影响.田间试验结果表明:接菌量在播种后40天和60天没有显著增加根瘤数、根瘤干重、地上部植株干重和植株含氮量.施氮肥处理和较高接菌量处理之间的大豆种子产量差异不显著,与不接菌对照处理相比,施氮肥和较高接菌量两个处理的种子产量显著增加.施氮肥处理没有使植株含氮量增加,并且还妨碍了大豆的结瘸作用.室内盆栽试验结果表明:只有当接菌量高于土著菌数1200倍时,才能显著地提高大豆的结瘤数和植株干重.     

钒对大豆结瘤和固氮的影响

通过土培试验研究了钒对春大豆、秋大豆结瘤和固氮的影响，试验结构表明：钒处理影响大豆结瘤，使大豆植株单株瘤数、单株重减少。但钒可促进根瘤个体发育使根瘤个体重量增加，钒处理还增加大豆根瘤因氮酶活性，但不能增加大豆－－根瘤共生固氮体系的固氮效率。     

两株芽孢杆菌对茶用菊红心菊生长和品质的影响

为探讨从不同品种菊花根际土壤中分离的两株芽孢杆菌对茶用菊生长和品质的影响,以茶用菊红心菊为试验材料,研究对照(CK)、接种解淀粉芽孢杆菌处理(Ba)、接种枯草芽孢杆菌处理(Bs)、接种解淀粉芽孢杆菌和枯草芽孢杆菌混合处理(Ba+Bs)对茶用菊红心菊各生育期生理指标的影响。结果表明,苗期菌剂对各生理指标的促生效果显著高于生长期和花期;花期时,菌剂接种处理均不同程度地促进了茶用菊红心菊收获时品质和产量的提高,其中绿原酸、木犀草苷、3,5-二咖啡酰基奎宁酸含量与CK相比平均提高20%左右,且三组接种菌剂处理之间无显著差异,而Ba+Bs处理后红心菊的黄酮含量最高,比CK提高15.64%,同时该处理红心菊的估产量也最高,比CK、Ba和Bs分别提高了152.00%、64.12%和33.61%。综上所述,在茶用菊苗期栽培土壤中混合接种解淀粉芽孢杆菌和枯草芽孢杆菌(Ba+Bs)可以显著提高红心菊外观品质、花期产量以及茶用品质。本研究结果为今后茶用菊功能微生物有机肥研发奠定了良好的基础。     

马占相思根瘤菌结瘤固氮特性的分析

相思属（Acacia）树种是速生的热带、亚热带豆科植物。对现在大面积种植的相思树品种——马占相思的根瘤菌进行分离和筛选，获得菌株若干株，对它们的结瘤固氮特性和对马占相思、大叶相思及厚荚相思生长的影响等进行了初步研究。结果表明。无氮条件下接种马占相思根瘤菌，能显著促进这3个树种的株重、株高和生物量的增长；苗圃接种马占相思根瘤菌。马占相思苗高增加27．6％，地径增加14．8％，植株鲜重增加32．6％，结瘤数增加83．8％。     

根瘤菌与促生菌双接种对大豆生长和土壤酶活的影响

【目的】慢生大豆根瘤菌和胶质类芽孢杆菌单一菌株固氮或促生效果及机理已有较多研究,但两者双接种对作物的作用和增产机理尚未有所报道。本研究以慢生大豆根瘤菌5136与胶质类芽孢杆菌3016为研究对象,通过田间小区试验研究根瘤菌与促生菌不同施用模式对大豆生长和土壤酶活的影响,以期为开发新型高效复合菌剂提供理论依据。【方法】试验设对照(T1)、接种胶质类芽孢杆菌3016菌剂(T2)、接种慢生大豆根瘤菌5136菌剂(T3),胶质类芽孢杆菌3016和慢生大豆根瘤菌5136双接种(T4)和常规施肥(T5)5个处理,分别于大豆不同生育期调查大豆的农艺性状和结瘤状况,测定土壤酶活性,用BOX-PCR技术监测慢生大豆根瘤菌5136的占瘤率。【结果】1)在大豆成熟期,双接种(T4)处理的大豆单株分枝数、单株粒数、收获指数和产量均为最高,分别比T1高11.3%、9.7%、41.0%和9.3%,且单株空荚数最低,比T1降低了44.0%。2)在花荚期,双接种(T4)处理的占瘤率为25.4%,比T3处理高8.0%,且单株根瘤数和单株根瘤干重均为最高,分别比T1高41.6%和47.1%;说明双接种处理下,胶质类芽孢杆菌3016能够促进慢生大豆根瘤菌5136结瘤固氮。3)接种微生物菌剂均可不同程度地提高土壤酶活性,以双接种(T4)处理的效果最为显著,在大豆成熟期,土壤过氧化氢酶、脲酶和蔗糖酶活性均为最高,分别比对照高12.9%、8.9%和9.4%。4)相关性分析表明,土壤酶活性与大豆收获指数显著正相关或极显著正相关(P0.01或P0.05),其中过氧化氢酶与产量显著正相关;单株根瘤数和单株根瘤干重均与收获指数和蔗糖酶活性呈极显著正相关,与产量呈显著正相关。【结论】慢生大豆根瘤菌和胶质类芽孢杆菌双接种可以促进大豆生长,显著增加大豆的单株分枝数、单株粒数、收获指数和占瘤率,降低单株空荚数,增加大豆产量,同时可显著提高相关土壤酶活性,是一种节本增效的农艺措施。     

安徽省北部大豆根瘤菌的分离,血清学分析及田间自然结瘤调查

对安徽省北部分离的２７株快生大豆根瘤菌和３８株慢生大豆根瘤菌的血清学分析及田间自然结瘤的血清学调查表明：００５血清型系安徽北部夏大豆产区占据优势的血清型，１８组样品和再现频率为１００％；３６株分离物中２６株属００５血清型，占总分离物的７２．５％。２０４８血清型出现频率为８３．３％；在３组样品中占瘤率达４１－５１。６％。２１７血清型占瘤率普遍低于１６％。讨论了自然结瘤调查中采样地点，大豆品种和土壤类     

含枯草芽孢杆菌肥料对大豆叶片光合作用及土壤酶活性的影响

为了减少大豆生产过程中化肥的施用量及对黑土地的保护,开展大豆田间试验,分别施用大豆专用复合肥(CK)、枯草芽孢杆菌+氨基酸型有机肥(T1)、枯草芽孢杆菌+黄腐酸钾肥(T2)、枯草芽孢杆菌+海藻精粉颗粒肥(T3)、枯草芽孢杆菌秸秆腐熟有机肥(T4)、枯草芽孢杆菌鸡粪腐熟有机肥(T5),综合评价各种肥料对大豆光合作用和土壤...     

Enhanced soybean (Glycine max L.) plant growth and nodulation by Bradyrhizobium japonicum-SB1 in presence of Bacillus thuringiensis-KR1

Abstract

Nodulation and subsequent nitrogen fixation are important factors that determine the productivity of soybean (Glycine max L.). The beneficial effects of nodulation can be enhanced when rhizobial inoculation is combined with plant-growth-promoting bacteria (PGPB). The PGPB strain Bacillus thuringiensis-KR1, originally isolated from the nodules of Kudzu vine (Pueraria thunbergiana), was found to promote growth of soybean plants (variety VL Soya 2) under Jensen's tube and growth pouch conditions, when co-inoculated with Bradyrhizobium japonicum-SB1. Co-inoculation with Bacillus thuringiensis-KR1 (at a cell density of 10 cfu) provided the highest and most consistent increase in nodule number, shoot weight, root weight, root volume, and total biomass, over rhizobial inoculation and control, under both conditions. The results demonstrate the potential benefits of using nonrhizobial nodule occupants of wild legumes for the co-inoculation of soybean, with Bradyrhizobium japonicum-SB1, in order to achieve plant-growth promotion and increased nodulation.     

Potential for enhancement of root growth and nodulation of soybean co-inoculated with Azospirillum and Bradyrhizobium in laboratory systems

The potential enhancement of root growth and nodulation in vegetable soybean (AGS190) was studied with application of Azospirillum brasilense (Sp7) and A. lipoferum (CCM3863) co-inoculated with two Bradyrhizobium japonicum strains (TAL102 and UPMR48). Significant root growth stimulation and nodulation were observed in Azospirillum as well as during its co-inoculation with Bradyrhizobium. Nodule formation is linked with the initiation of new roots; nodules were almost absent even in Bradyrhizobium inoculated plant due to the absence of new roots development in clipped rooted seedlings. Total root length, root number, specific root length, root dry matter, root hair development and shoot dry matter were significantly increased by Azospirillum alone and its co-inoculum. Co-inoculated plants significantly influenced the number of nodules and its fresh weight. A. brasilense seemed to perform better in root growth and nodule development compared to A. lipoferum.     

Effect of some fungicide seed treatments on the survival of Bradyrhizobium japonicum and on the nodulation and yield of soybean [Glycine max. (L) Merr.]

Several commercial fungicide seed treatments were evaluated for their possible effect on the survival of Bradyrhizobium japonicum on seeds and on the nodulation and yield of soybeans in a greenhouse and a field experiment. quinolate Pro (carbendazim and oxine copper), Vitavax 200FF (carboxin and thiram), and Monceren (pencycuron) had a small effect or no effect on the survival of B. japonicum and on the nodulation and yield of soybeans. They can thus be considered compatible with soybean seed inoculation. Germipro UFB (carbendazim and iprodione), Apron 35J (metalaxyl), and Tachigaren (hymexazol) decreased B. japonicum survival and the nodulation and yield of soybeans and thus cannot be considered compatible with soybean seed inoculation.     

Effect of organic matter on the growth,nodulation, and nitrogen fixation of soybean grown under acid and saline conditions

Abstract

A field experiment was conducted to examine the effects of two organic materials (Bark and Tenporon composts) on the growth, nodulation and nitrogen fixation (measured as acetylene-reducing activity) of soybean plants (Glycine max L.) under acid and saline conditions. These organic materials were incorporated into acid and saline (induced by irrigating the soil with a NaCl solution) soils at 4% rate of application.

These composts tended to improve nodule formation in soybean under acid and saline conditions, especially in the plants treated with Bark compost. Acetylene-reducing activity was significantly (P<0.05) increased by these composts under acid condition.

These composts also tended to improve shoot growth under acid and saline conditions, presumably due to the improvement of the soil moisture status of the soils and nutrient uptake. These results suggest that the growth of soybean could be improved by the application of organic matter under acid and saline conditions.     

Effect of placement of coated urea fertilizer on root growth and rubidium uptake activity in soybean plant

Abstract

We reported in the previous paper (Takahashi et al. 1991) that the deep placement of slow release N fertilizer (coated urea) contributed to a stable increase of soybean (Glycine max L. Merr.) yield. In the previous study we observed that the deep placement of coated urea did not depress appreciably the nitrogen fixation by root nodules although fertilizer N was efficiently utilized. We assumed that the N absorbed from the roots in the deep layers did not cause nodule senescence, contributed to the maintenance of the leaf activity during the maturation stage, and that the increase in the availability of carbohydrate and N improved seed production. In the current report the effects of placement of coated urea fertilizer on the root growth and activity were studied by measuring the root dry weight and Rb absorption activity.     

Effect of soil pH on plant growth and nodulation of cowpea

Abstract

A study was conducted to evaluate the effect of soil pH on rhizobium inoculation, plant growth and nodulation of cowpea (Vigna unguiculata). Both inoculated and non‐inoculated seeds of the cultivar ‘California Blackeye No. 5’ were grown in the greenhouse in plastic pots with growth medium being a Norfolk sandy loam (Fine, loamy siliceous, thermic, Typic Palendult) soil under different pH levels. Both soil pH and rhizobium inoculation significantly affected root length, plant height, nodule and pod number per plant. Within the pH range of 6.6 to 7.6, these growth parameters generally were at their maximum, decreasing above or below this pH range. Non‐inoculated plants produced some nodules, indicating failure of the methyl bromide to totally destroy all residual soil rhizobta before inoculation treatment.

The inoculated plants produced more seeds and the increased number of nodules of treated plants was directly related to increased seed weight. Since nodule number was highest at the approximate pH range of 6.6 to 7.6, this range was considered optimum for nodulation of cowpea by this strain of rhizobium under greenhouse conditions. At pH 7.5 and above, roots tended to be more fibrous and nodules were generally smaller in size.     

Effect of nodulation with Bradyrhizobium japonicum and Shinorhizobium fredii on xylem sap composition of Peking (Glycine max L. Merr )

Five barley cultivars were grown together in complete, low-P·low-pH and high-Al medium containing only NO₃, only NH₄ or both NO₃ and NH₄ as N sources, respectively using an automatic control system of pH for water culture, and the relationship between the differential Al tolerance and the plant-induced pH change of medium among the barley cultivars was investigated.

The pH of the medium containing only NO₃ as N source tended to increase, whereas the pH of the other media containing only NH₄ or both NO₃ and NH₄ as N sources tended to decrease, but the fluctuations of the medium pH could be maintained within the value of 0.2 pH in the complete medium and within the value of 0.1 pH in the high-Al medium.

Barley cultivars still differed in their Al tolerance in the medium which was continuously stirred and circulated at a constant pH. The pattern of Al tolerance was not affected by the N sources in the medium. The plant-induced pH change of medium for each cultivar was influenced by the N sources in the medium, and was not correlated positively with Al tolerance. The contents of Al and Ca or other nutrient cations in roots were positively correlated with Al tolerance and positive correlations were recognized also between the contents of Al and Ca or some other nutrient cations in the roots.

In conclusion, the following mechanisms are proposed. Al tolerant barley cultivars exclude Al actively outside the plasmalemma of the root cells, and the excluded Al may polymerize and or react with P to form Al precipitates. Consequently, in the Al tolerant barley cultivars the Al content may be low in the root protoplasts, high in the whole root tissues and the contents of Ca or other nutrients may be high in the roots. The plant-induced pH change of medium is not considered to be the cause of the differential Al tolerance among barley cultivars.     

Effect of soybean inoculation with Bradyrhizobium and wheat inoculation with Azotobacter on their productivity and N turnover in a Vertisol

A long-term field experiment was conducted for 8 years on a Vertisol in central India to assess quantitatively the direct and residual N effects of soybean inoculation with Bradyrhizobium and wheat inoculation with Azotobacter in a soybean–wheat rotation. After cultivation of soybean each year, its aerial residues were removed before growing wheat in the same plots using four N levels (120, 90, 60 and 30 kg ha^?1) and Azotobacter inoculation. Inoculation of soybean increased grain yield by 10.1% (180 kg ha^?1), but the increase in wheat yields with inoculation was only marginal (5.6%; 278 kg ha^?1). There was always a positive balance of soil N after soybean harvest; an average of +28 kg N ha^?1 yr^?1 in control (nodulated by native rhizobia) plots compared with +41 kg N ha^?1 yr^?1 in Rhizobium-inoculated plots. Residual and direct effects of Rhizobium and Azotobacter inoculants caused a fertilizer N credit of 30 kg ha^?1 in wheat. Application of fertilizers or microbial inoculation favoured the proliferation of rhizobia in crop rhizosphere due to better plant growth. Additional N uptake by inoculation was 14.9 kg N ha^?1 by soybean and 20.9 kg N ha^?1 by wheat crop, and a gain of +38.0 kg N ha^?1 yr^?1 to the 0–15 cm soil layer was measured after harvest of wheat. So, total N contribution to crops and soil due to the inoculants was 73.8 kg N ha^?1 yr^?1 after one soybean–wheat rotation. There was a total N benefit of 13.8 kg N ha^?1 yr^?1 to the soil due to regular long-term use of microbial inoculants in soybean–wheat rotation.     

Effects of Rhizobium inoculation and magnesium application on growth and nodulation of soybean (Glycine max L.)

Abstract

Magnesium (Mg) deficiency is one of the major nutritional problems in tropic and subtropic areas, where the most soils are acidic. In this study, the effects of Mg application and Bradyrhizobium inoculation on growth, nodulation, symbiotic nitrogen (N) fixation as well as N nutrition status in soybean (Glycine max L.) were investigated in hydroponics under greenhouse conditions. With the increase of Mg up to 0.75?mM at low N and up to 0.5?mM at high N solutions, the dry weights of shoots, roots, and pod grain yield in soybean were increased, while further increase in Mg supply inhibited soybean growth. The availability of Mg was found to entail an improved uptake of N by plants and nodulation process in the root by Bradyrhizobium. Inoculation with rhizobial inoculants not only formed many nodules, but also increased soybean shoot, root biomass and yield, as well as plant N nutrient status.