Associative effect of Rhizobium and phosphate-solubilizing bacteria on the yield and nutrient uptake of chickpea

Combined inoculation of Rhizobium and ‘Phosphate-solubilizing’Pseudomonas striata orBacillus polymyxa with and without added chemical fertilizer on chickpea yield and nutrient content was studied under greenhouse conditions. While the single inoculation of Rhizobium increased the nodulation and nitrogenase activity, the ‘phosphate-solubilizers’ increased the available phosphorus content of the soil. Combined inoculation of Rhizobium andP. striata orB. polymyxa increased the above parameters and also the dry matter content, the grain yield and nitrogen and phosphorus uptake significantly over the uninoculated control. The inoculation effects were more pronounced in the presence of added fertilizers. The possibilities of saving half the dose of N and replacing superphosphate with rockphosphate and inoculation with ‘phosphate-solubilizers’ are discussed.     

Nitrogen limitations to field bean productivity: A comparison of combined nitrogen applications with Rhizobium inoculation

Summary Nitrogen limitations to the yield of a field crop ofVicia faba have been examined. Application of nitrogen totalling 560 kg/ha increased dry matter yield at flowering by 674 kg/ha (32%) and grain yield at final harvest by 1.6 tonnes/ha (24%). Attempts to reduce nitrogen limitations by replacing the native rhizobia with strains ofRhizobium leguminosarum selected for high rates of nitrogen fixation were unsuccessful but the introduction of poor rhizobia reduced grain yield. The reasons for this and the implications of the results for crop improvement are discussed.     

Field experiments on nitrogen fixation by nodulated legumes

Summary Phosphate increased nitrogen uptake by lucerne appreciably on a saline soil. Nitrogenous fertiliser or inoculation with an effective strain ofRhizobium meliloti did not increase the yield significantly. In soils where indigenousRhizobium japonicum was absent inoculation increased soybean yields and the additional fixed nitrogen removed by soybeans amounted to 40 to 120 kg ha⁻¹. Gram and groundnut also responded to Rhizobium inoculation in field trials.     

Associative effect of cellulolytic fungi andAzospirillum lipoferum on yield and nitrogen uptake by wheat

The associative effect of cellulolytic fungi, such asAspergillus awamori andA. niger, with the nitrogen fixer,Azospirillum lipoferum was studied in a soil amended with rice straw. All the inoculants gave significantly higher grain and straw yield and nitrogen uptake by wheat crop than did the uninoculated treatment. The doubling of chemical nitrogen dose significantly increased the yield and nitrogen uptake. It was observed thatA awamori performed significantly better followed byA. niger andA. lipoferum. The maximum benefit was obtained with combined inoculation ofA. awamori andA. lipoferum. Another experiment was conducted in the subsequent year in soil amended with and without rice straw using cellulolytic culture eitherA. awamori orSclerotium rolfsii, andA. lipoferum. Application of straw in soil significantly reduced the yield and N-uptake by wheat crop as compared to the controls. All the inoculants exceptS. rolfsii gave significantly higher grain yield. However, N-uptake by grain was significantly increased only by combined inoculation ofA. lipoferum and either one of the cellulolytic fungi. Similar trends on yield and N-uptake of straw due to inoculants were observed. The maximum benefit was obtained with combined inoculation ofA. awamori andA. lipoferum followed byA. awamori alone on grain yield and only combined inoculants on N-uptake by the crop.     

Associative effect ofAzospirilium brasilense withRhizobium japonicum on nodulation and yield of soybean (Glycine max)

Summary Azospirillum was associated with nodules of soybean. In general, seed inoculation with a broth culture ofAzospirillum brasilense alone significantly increased nodulation and grain yield of soybean grown in pots in unsterilized soil with different levels of urea ranging from 0 to 80 kg N/ha. This trend was significantly reproducible in a second experiment when a carrier based inoculant of the bacterium was used for seed inoculation.Inoculation withRhizobium japonicum andA. brasilense in combination generally increased grain yield in both the experiments, although the data were not significant.     

Effect of salinity and inoculation on growth,nitrogen fixation and nutrient uptake ofVigna radiata (L.) Wilczek

This study reports the effect of salinity and inoculation on growth, ion uptake and nitrogen fixation byVigna radiata. A soil EC_e level of 7.5 dS m⁻¹ was quite detrimental causing about 60% decline in dry matter and grain yield of mungbean plants whereas a soil EC_e level of 10.0 dS m⁻¹ was almost toxic. In contrast most of the studied strains of Rhizobium were salt tolerant. Nevertheless, nodulation, nitrogen fixation and total nitrogen concentration in the plant was drastically affected at high salt concentration. A noticeable decline in acetylene reduction activity occurred when salinity level increased to 7.5 dS m⁻¹.     

Enhancement of nitrogen fixation in lentil,faba bean,and soybean by dual inoculation with Rhizobia and mycorrhizae

The combined effect of Vesicular Arbuscular Mycorrhizae (VAM) and Rhizobium on the cold season legumes, lentil and faba bean, as well as on summer legume, soybean, were studied in soils with low indeginous VA mycorrhizal spores. Inoculation of the plant with VA mycorrhizal fungi increased the level of mycorrhizal root infection of lentil, faba bean and soybean. The inoculation with Rhizobium had no significant effect on VA mycorrhizal infection percent, but VA mycorrhizal inoculation increased nodulation of the three legumes. The inoculation with Rhizobium alone significantly increased plant dry weight and N content of lentil and faba bean as well as seed yield of soybean. VA mycorrhizal inoculation also significantly increased plant dry weight and phosphorus content of the plants as did fertilization with superphosphate. Rock phosphate fertilization, however, had no significant effect on plant growth or phosphorus uptake. The addition of rock phosphate in combination with VA mycorrhizal inoculation significantly increased plant dry weight and P uptake of the plants. The dual inoculation with both rhizobia and mycorrhizae induced more significant increases in plant dry weight, N and P content of lentil and faba bean as well as seed yield of soybean than inoculation with either VA mycorrhizae or Rhizobium alone.     

Persistence and competitiveness of threeBradyrhizobium japonicum inoculant strains in clay loam Nile valley soil

The nitrogen contribution from the shoot and root system of symbiotically grown leucaena was evaluated in a field experiment on an Alfisol at IITA in Southern Nigeria. Maize in plots that received prunings from inoculated leucaena contained more N and grain yield was increased by 1.9 t.ha.^–1. Large quantities of nitrogen were harvested with leucaena prunings (300 kg N ha^–1 in six months) but the efficiency of utilization of this nitrogen by maize was low compared to inorganic N fertilizer (ammonium sulphate) at 80 kg N ha^–1. Maize yield data indicated that nitrogen in leucaena prunigs was 34 and 45% as efficient as 80 kg N ha^–1 of (NH₄)₂SO₄ for uninoculated and inoculated plants with Rhizobium IRc 1045, respectively. In plots where the prunings were removed, the leaf litter and decaying roots and nodules contributed N equivalent of 32 kg ha^–1. Twenty-five kg ha^–1 was the inorganic N equivalent from nitrogen fixed symbiotically by leucaena when inoculated with Rhizobium strain IRc 1045. Application of prunings from inoculated leucaena resulted in higher soil ogranic C, total N, pH and available NO₃.     

固氮菌接种对棉苗氮磷钾吸收、某些酶活性及产量的影响(英文)

Spermospheremodels和盆栽试验结果表明 ,海岛棉 (GossypiumbarbadenseL .)苗接种自生固氮菌(Azotobactersp .)、巴西固氮螺菌NO40 (AzospirillumbrasilenseNO40 )、多粘芽孢杆菌 (BacilluspolymyxaCF)和根瘤菌 (Rhizobium) ,和以自生固氮菌分别与其它 3种供试菌种两者的混合菌 ,能增强棉花根际固氮酶活性和棉苗对氮的吸收 ,提高功能叶中氮、磷和叶绿素含量 ,从而有利于提高生物学产量 ,尤以自生固氮菌的促进效应最为显著。另一方面 ,混合菌处理较单一菌株处理 ,可以显著提高棉苗对氮的吸收 ,增加干物质积累提高皮棉产量 ,其中尤以固氮菌分别与根瘤菌或巴西固氮螺菌NO40的协同效应最显著     

Substrate-dependent auxin production by Rhizobium phaseoli improves the growth and yield of Vigna radiata L. under salt stress conditions

Rhizobium phaseoli strains were isolated from the mung bean nodules, and, the most salt tolerant and high auxin producing rhizobial isolate N20 was evaluated in the presence and absence of L-tryptophan (L-TRP) for improving growth and yield of mung bean under saline conditions in a pot experiment. Mung bean seeds were inoculated with peat-based inoculum and NP fertilizers were applied at 30-60 kg ha-1, respectively. Results revealed that imposition of salinity reduced the growth and yield of mung bean. On the contrary, separate application of L-TRP and rhizobium appeared to mitigate the adverse effects of salt stress. However, their combined application produced more pronounced effects and increased the plant height (28.2%), number of nodules plant-1 (71.4%), plant biomass (61.2%), grain yield (65.3%) and grain nitrogen concentration (22.4%) compared with untreated control. The growth promotion effect might be due to higher auxin production in the rhizosphere and improved mineral uptake that reduced adverse effects of salinity. The results imply that supplementing rhizobium inoculation with L-TRP could be a useful approach for improving growth and yield of mung bean under salt stressed conditions.     

The response of field grownPhaseolus vulgaris to Rhizobium inoculation and the quantification of N2 fixation using15N

Summary A field experiment was performed to assess the effects of Rhizobium inoculation and nitrogen fertilizer (100 kg N ha^–1) on four cultivars of Phaseolus beans; Carioca, Negro Argel, Venezuela 350 and Rio Tibagi. In the inoculated treatment 2.5 kg N ha^–1 of¹⁵N labelled fertilizer was added in order to apply the isotope dilution technique to quantify the contribution of N₂ fixation to the nutrition of these cultivars.Nodulation of all cultivars in the uninoculated treatments was poor, but the cultivars Carioca and Negro Argel were well nodulated when inoculated. Even when inoculated, nodulation of the cultivars Venezuela 350 and Rio Tibagi was poor and these cultivars showed little response to inoculation in terms of nitrogen accumulation or grain yield. The estimates of the contribution of N₂ fixation estimated using the isotope dilution technique, for the Carioca and Negro Argel cultivars, amounted to 31.7 and 18.4 kg N ha^–1 respectively. These two cultivars produced 991 and 883 kg ha^–1 of grain, respectively, when inoculated and 663 and 620 kg ha^–1 with the addition of 100 kg N ha^–1 of N fertilizer. The response to nitrogen was particularly poor due to high leaching losses in the very sandy soil at the experimental site.The Venezuela 350 and Rio Tibagi cultivars only responded to N fertilizer and not to inoculation with Rhizobium which stresses the great importance of selecting plant cultivars for nitrogen fixation in the field.     

A greenhouse study on the effect of inoculation of N-fixing blue-green algae in an alluvial soil treated with P and Mo on the yield of rice and changes in the N-content of soil

Summary The efficiency of the inoculation of three cultures of N-fixing blue-green algaeviz. (i)Aulosira fertilissima (A₁), (ii)Nostoc muscorum (A₂) and (iii) their mixture (A₃) in increasing the grain and straw yield of rice, nitrogen uptake in grain and nitrogen content in soil was studied in a green house experiment with an alluvial soil in presence or absence of urea nitrogen application. Inoculation significantly increased the grain and straw yield of rice and nitrogen uptake in grain, but the efficiency of inoculation gradually decreased with the increase in the levels of urea nitrogen application, the extent of decrease varying with the algal cultures inoculated. The nitrogen content in the soils after the crop harvest recorded a significant increase due to inoculation but after air drying the soil a marker decrease of the same was observed, which indicated that most of the nitrogen added to the soil by blue-green algae through fixation did not persist after air drying the soil.     

Dual inoculation withRhizobium sp. andGlomus fasciculatum enhances nodulation,yield and nitrogen fixation in chickpea (Cicer arietinum Linn.)

Summary Seed inoculation with Rhizobium and soil inoculation withGlomus fasciculatum increased nodulation, nitrogen and phosphorus concentration in plants and yield of chickpea (Cicer arietinum) var. BG 212 in pots containing unsterilized soil especially with 50kgP₂O₅ ha⁻¹ in the form of superphosphate. Inoculation with Rhizobium orG. fasciculatum separately or in combination significantly increased the N₂ fixed in straw and grain than uninoculated controls as determined by¹⁵N atom percent excess of plants grown in soil amended with labelled ammonium sulphate (¹⁵NH₄)₂SO₄) at the rate of 20kg N ha⁻¹. These increases were most pronounced when P was applied at 50kgP₂O₅ ha⁻¹.     

Contributions and limitations to symbiotic nitrogen fixation in common bean (Phaseolus vulgaris L.) in Romania

Common beans usually achieve grain yields less than the genotypic potential of the cultivar under Romanian field conditions. To understand better the contribution of nitrogen fixation to the yield formation, I made a long-term evaluation (1977–1994) of inoculation effects of 19 Rhizobium leguminosarum bv. phaseoli strains on common bean cultivated in several locations. Grain yields were significantly influenced by all selected strains, years and locations in all experimental cycles, and only partially by the interactions between strains and years or strains and locations. The average yield increases induced by these strains during the four cycles ranged from 6 to 20%. Four bacterial strains proved to be more stable in their field performances, taking into account the yield increases greater than 10% over controls observed in all individual trials. Mean yields and variation limits recorded during the long-term evaluation of strain efficacy in locations with different soil pH values showed similar patterns of yield increases from soils with acidic to neutral pH values. Linear regression between mean grain yields and average temperatures demonstrated the limiting effect of temperature on yield. The interaction between bacterial strain and nitrogen fertiliser rate demonstrated the ability of dinitrogen fixation to satisfy the crop requirements for this element. An evaluation of the amounts of nitrogen fixed in three common bean cultivars inoculated with two bacterial strains showed different N2-fixing capacities among plant genotypes.     

Repeated beneficial effects of rice inoculation with a strain of Burkholderia vietnamiensison early and late yield components in low fertility sulphate acid soils of Vietnam

TVV75, a strain of Burkholderia vietnamiensis, was isolated from an acid sulphate soil of south Vietnam, and selected for its high in vitro nitrogen fixation potential. This plant growth-promoting rhizobacterium (PGPR) had been used in a previously reported pot experiment. It was used in two new pot experiments and four field experiments to inoculate lowland rice at sowing and at transplanting, in three different South Vietnam acid sulphate soils. We first studied the effect of inoculation during early plant growth in nurseries. Seedlings were then transplanted both to field and pots. Treatments included two levels of inoculation (inoculated vs uninoculated) and three levels of N fertilizer (0, recommended rate and half this rate), in a randomized block design with six replicates. In all four experiments nitrogen appeared to be the limiting factor for yield. Inoculation had already had a strong beneficial effect at the transplanting stage (day 24), as measured by shoot weight (+33%) root weight (+57%), and leaf surface (+30% at day 14). Final results indicated that inoculation of rice with B. vietnamiensis TVV75 significantly increased several yield components, resulting in a final 13 to 22% increase in grain yield. A late yield component, 1,000 grain weight, was significantly increased by inoculation, but not by nitrogen fertilizers, in all pot and field experiments, indicating a long-lasting effect of the inoculated bacteria. It was possible to evaluate the nitrogen fertilizer equivalent of inoculation (NFEI): at the medium rate of N fertilizer, inoculation ensured a yield equivalent to that obtained in the uninoculated control with 25 to 30 kg more nitrogen fertilizer. Comparison of the local cost of NFEI kg N-fertilizer and the cost of inoculation would help in making the decision to inoculate. This revised version was published online in August 2006 with corrections to the Cover Date.     

Effects of Rhodobacter capsulatus inoculation in combination with graded levels of nitrogen fertilizer on growth and yield of rice in pots and lysimeter experiments

A pot and a lysimeter experiment were carried out to study the effects of inoculation of the roots of rice seedlings with R. capsulatus in combination with graded levels of nitrogen (N) fertilizer on growth and yield of the rice variety Giza 176. Inoculation increased all the measured growth parameters and yield attributes, but the statistically significant differences at all N levels tested were only those for plant dry weight, number of productive tillers, grain and straw yields. The absolute increases in grain yield of the pot experiment due to inoculation were 0.63, 0.93 and 1.22 ton ha^–1 at 0, 47.6 and 95.2 kg N ha^–1, respectively. The results suggest that inoculation along with 47.6 kg N ha^–1 can save 50% of the nitrogen fertilizer needed for optimum G176 rice crop. However, inoculation along with 95.2 kg N ha^–1 can increase grain yield by about 1.2 ton ha^–1. This is probably the first reported evidence of a beneficial effect of phototrophic purple nonsulphur bacteria on rice growth and yield under flooded soil conditions.     

Inoculation of pea (Pisum sativum L.) by Rhizobium leguminosarum bv. viceae preincubated with naringenin and hesperetin or application of naringenin and hesperetin directly into soil increased pea nodulation under short season conditions

In short season areas, low soil temperature is the major limiting factor for symbiotic nitrogen fixation of legume. One greenhouse and four field experiments were conducted in 1999 to determine whether the pre-incubation of Rhizobium leguminosarum bv. viceae with hesperetin and naringenin or application of these compounds onto the seed surface or into the seed furrow at the time of planting can increase pea nodulation and final grain yield. The results from these experiments clearly indicated that application of naringenin and hesperetin by either pre-incubating R. leguminosarum bv. viceae prior to inoculation of plant or directly applying onto the seed surface or into seed furrow at the time of planting can increase pea nodulation, and plant pod numbers. Interactions existed between symbiotic signal compounds and pea cultivars or R. leguminosarum bv. viceae strains. However, there was no impact on the final grain yield by the treatments from the field experiments. The effects of these treatments on the final grain yield have to be farther tested.     

丛枝菌根真菌和根瘤菌互作对苜蓿根际土壤细菌群落结构的影响及PICRUSt功能预测分析

【背景】紫花苜蓿是优良的豆科牧草,可以与丛枝菌根(Arbuscular mycorrhizae,AM)真菌和根瘤菌形成共生关系,接种AM真菌和根瘤菌可以促进土壤氮、磷循环以及提高苜蓿产量。【目的】探究接种AM真菌和根瘤菌对苜蓿根际细菌群落结构和功能的影响。【方法】采集6个不同处理组苜蓿根际、非根际土壤样品,基于细菌16S rRNA基因V3?V4区进行高通量测序,分析比较不同处理组苜蓿根际、非根际土壤中细菌群落分布的规律,并采用PICRUSt软件对不同处理组间菌群功能进行预测。【结果】36个土壤样品中共检测到3 849个OTU,分属于50门59纲132目249科595属398种。其中主要的优势菌门为Proteobacteria (52.81%?81.46%)、Bacteroidetes (7.83%?19.68%)及Actinobacteria (2.21%?16.4%)。与不接种相比,接种根内球囊霉和摩西球囊霉分别提高了Gammaproteobacteria和Bacteroidia有益菌的丰度,接种根瘤菌提高了固氮菌(Alphaproteobacteria)的丰度。PICRUSt功能预测表明,细菌菌群共有35个子功能,菌群功能丰富,代谢为最主要的功能,并且接种根瘤菌可增加氨基酸代谢,从而有利于植株N素循环,而接种AM真菌可能对于N循环有一定的抑制作用,相比于单接种AM真菌,双接种AM真菌和根瘤菌处理组碳水化合物代谢更强,从而更有益于植株的氮、磷循环。【结论】接种AM真菌和根瘤菌可分别提高苜蓿根系与氮、磷循环有关的不同有益菌的丰度,从而更有益于植株的氮、磷循环,该结果为提高植株养分吸收、提高苜蓿产量以及菌肥开发利用提供了科学依据。     

Use ofAzospirillum brasilense as biofertilizer in intensive wheat cropping

Summary Three field experiments were conducted on ten cultivars of winterwheat and four cultivars of springwheat to estimate the growth promoting effect ofAzospirillum brasilense under varying nitrogen doses. Independent of cultivar selection or nitrogen dose a highly significant yield increase could be observed in winterwheat: strains S631 and SpBr14 increased the average grain yield with 9.14% and 14.82% respectively. When the yield components were studied a coinciding increase in ear density could be demonstrated of resp. 10.57% and 13.55%. Less significant results were obtained with springwheat although in one experiment strain SpBr14 significantly increased grain yield. As with winterwheat tillering of the plant was markedly affected by inoculation with both strains. In a companion greenhouse experiment it was found that inoculation with Azospirillum can cause a decrease in the root mass of wheatplants except when strain SpBr14 is used. Therefore it is suggested that the presence of a higher tillering together with an undisturbed nutrient uptake capacity can result in yield increases after inoculation withAzospirillum brasilense.     

Significance of<Emphasis Type="Italic">Herbaspirillum seropedicae</Emphasis> inoculation and/or straw amendment on growth and dinitrogen fixation of wheat using<Superscript>15</Superscript>N-dilution method

The effect of Herbaspirillum seropedicae inoculation and/or maize straw (0, 5 and 10 Mg/hm2) amendment on the growth and N2 fixation of wheat was determined in pot experiments using 15N-dilution method. Inoculation resulted in accumulation of fixed nitrogen, and % N from atmosphere being 24.6 and 26.5% in wheat shoot and grain, respectively. Straw amendment reduced % Natm to 16.1 and 20.2% at high straw level (10 Mg/hm2). Rational nitrogen fertilization (180 kg N/hm2) completely inhibited N2 fixation by H. seropedicae inoculation. Bacterial inoculation increased dry shoot and grain yield up to 23 and 31%, respectively. The highest levels of shoot and grain dry mass (46.5 and 42.4%) were obtained by N-fertilization in both inoculated and uninoculated plants. Total shoot and grain N-yield increased irrespective of organic matter amendment by inoculation up to 9 and 25%, respectively. N-fertilized plants recorded a maximum increase in N-yield (57 and 51%). H. seropedicae was reisolated from inoculated wheat histosphere after harvesting (90 d from sowing). Neither organic matter nor mineral nitrogen applications had any marked effect on bacterial total counts colonizing wheat histosphere. Moreover, no symptoms of mottled stripe disease were observed on leaves and stems of inoculated plants.