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1.
Diversity of rhizobia nodulating Lotus corniculatus grown in geographical regions with different rainfall regimes in northern and southern Uruguay, was estimated using 168 root nodule isolates. ERIC-PCR analysis revealed no correlation between observed fingerprints and the geographical origin of isolates. Despite the commercial strain U510 has been used for decades to inoculate L. corniculatus, none of the isolates corresponded to this strain. Phylogenetic analyses using 16S rRNA and atpD genes, and ITS sequences clustered all the isolates within genus Mesorhizobium. A great majority of the isolates likely belong to the species M. huakuii, as does the commercial strain U510. The remaining isolates were closely related to either M. septentrionale or M. caraganae. Although no M. loti-like bacteria were identified, all isolates carried symbiotic genes closely related to M. loti and other narrow host range Lotus rhizobia. A significant portion of the Uruguayan isolates were as efficient as the reference strain U510 in symbiosis with L. corniculatus. A few of the isolates were also capable of nitrogen fixation in symbiosis with L. uliginosus, albeit with lower efficiency than reference strains. Our results indicate that rhizobia nodulating L. corniculatus in Uruguay are genetically and phenotypically diverse, and that the commercial strain U510 is probably not adapted to survive the Uruguayan edaphoclimatic conditions.  相似文献   

2.
《Soil biology & biochemistry》2012,44(12):2384-2396
We investigated the diversity of rhizobia isolated from different indigenous legumes in Flanders (Belgium). A total of 3810 bacterial strains were analysed originating from 43 plant species. Based on rep-PCR clustering, 16S rRNA gene and recA gene sequence analysis, these isolates belonged to Bradyrhizobium, Ensifer (Sinorhizobium), Mesorhizobium and Rhizobium. Of the genera encountered, Rhizobium was the most abundant (62%) and especially the species Rhizobium leguminosarum, followed by Ensifer (19%), Bradyrhizobium (14%) and finally Mesorhizobium (5%). For two rep-clusters only low similarity values with other genera were found for both the 16S rRNA and recA genes, suggesting that these may represent a new genus with close relationship to Rhodopseudomonas and Bradyrhizobium. Primers for the symbiotic genes nodC and nifH were optimized and a phylogenetic sequence analysis revealed the presence of different symbiovars including genistearum, glycinearum, loti, meliloti, officinalis, trifolii and viciae. Moreover, three new nodC types were assigned to strains originating from Ononis, Robinia and Wisteria, respectively. Discriminant and MANOVA analysis confirmed the correlation of symbiosis genes with certain bacterial genera and less with the host plant. Multiple symbiovars can be present within the same host plant, suggesting the promiscuity of these plants. Moreover, the ecoregion did not contribute to the separation of the bacterial endosymbionts. Our results reveal a large diversity of rhizobia associated with indigenous legumes in Flanders. Most of the legumes harboured more than one rhizobial endosymbiont in their root nodules indicating the importance of including sufficient isolates per plant in diversity studies.  相似文献   

3.
《Applied soil ecology》2007,35(1):57-67
Soils of many potential soybean fields in Africa are characterized by low levels of biological nitrogen fixation (BNF) activities and often cannot support high soybean yields without addition of inorganic N fertilizers or external application of soybean rhizobia. The most probable number (MPN) technique was used to determine the bradyrhizobial populations that nodulate TGx soybean genotypes (a cross between nonpromiscuous North American soybean genotypes and promiscuous Asian soybean genotypes), cowpea or North American soybean cv. Clark IV, in soils from 65 sites in 9 African countries. The symbiotic effectiveness of isolates from these soils was compared to that of Bradyrhizobium japonicum strain USDA110. The bradyrhizobial population sizes ranged from 0 to 104 cells g−1 soil. Bradyrhizobium sp. (TGx) populations were detected in 72% and B. japonicum (Clark) in 37% of the soil samples. Bradyrhizobium sp. (TGx) populations were generally low, and significantly less than that of the cowpea bradyrhizobial populations in 57% of the samples. Population sizes of less than 10 cells g−1 soil were common as these were detected in at least 43% of the soil samples. B. japonicum (Clark) occurred in higher population densities in research sites compared to farmers’ fields. Bradyrhizobium sp. (TGx) populations were highly correlated with biotic but not abiotic factors. The frequent incidence of low Bradyrhizobium sp. (TGx) populations is unlikely to support optimum BNF enough for high soybean yields while the presence of B. japonicum (Clark) in research fields has the potential to compromise the selection pressure anticipated from the indigenous Bradyrhizobium spp. (Vigna) populations. Bradyrhizobium isolates could be placed in four symbiotic phenotype groups based on their effectiveness on a TGx soybean genotype and the North American cultivar Clark IV. Symbiotic phenotype group II isolates were as effective as B. japonicum strain USDA110 on both soybean genotypes while isolates of group IV were effective on the TGx soybean genotype but not on the Clark IV. The group IV isolates represent a unique subgroup of indigenous bradyrhizobia that can sustain high soybean yields when available in sufficient population densities.  相似文献   

4.
The aim of this work was to investigate the genetic diversity, symbiotic effectiveness, drought tolerance, and indole acetic acid production of indigenous rhizobial populations in the Parque Chaqueño of Argentina able to nodulate Prosopis alba, the dominant forest tree of this region. The populations were sampled at five locations from the Arid, Semi-arid, and Humid Chaco in the Parque Chaqueño region. A set of rhizobial strains able to nodulate P. alba was obtained and selected based on their molecular diversity. Data obtained by BOX-PCR indicated that the highest molecular variability was observed in rhizobial isolates from Semi-arid Chaco. High level of indolic compound production and tolerance to osmotic treatment were significantly (p?≤?0.05) correlated with water restrictions of the environments where the strains belonged. A small set of rhizobial strains that stimulate P. alba growth was selected from a large group of strains. The strains were identified by 16S rDNA sequencing as belonging to the genera Mesorhizobium, Bradyrhizobium, and Ensifer. To our knowledge, this is the first report of P. alba nodulation by strains other than Mesorhizobium chacoense, which was already described for the Parque Chaqueño.  相似文献   

5.
Polyphasic characterization of 54 indigenous mung bean (Vigna radiata L.) rhizobia from different geographic regions of China was determined by analyzing the variability of 16S rRNA gene RFLP, 16S–23S rRNA gene Intergenetic Spacer (IGS) RFLP, G-C rich RAPD and phenotype assays. Based on these characteristics, mung bean rhizobia were clustered into four groups. Group I comprised 16 slow-growing isolates from a variety of geographic regions. This group was genetically distinct from Bradyrhizobium japonicum and Bradyrhizobium liaoningense, and may represent a new species. Group II was composed of 18 isolates, which could be sub-divided into two sub-groups that were respectively related to B. japonicum and B. liaoningense. Group III comprised 12 isolates from South China and clustered together with Bradyrhizobium elkanii. Group IV formed a miscellany of 8 fast-growing isolates variously related to the genera Sinorhizobium, Rhizobium and Mesorhizobium.  相似文献   

6.
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7.
Abstract

Caldwell and Vest (1968) planted soybeans (Glycine max L. Merr.) with various genotypes at Beltsville, USA, without inoculating them with Bradyrhizobium japonicum, and showed that soybeans preferred certain serotypes of rhizobial strains for nodulation. Recently, the authors have reported that soybeans carrying nodulation-conditioning genes preferred appropriate strains showing specific behavior for nodulation (Ishizuka et al. 1991). For instance, nodulation of soybean cv. Hardee which carries the nodulation-conditioning genes, Rj 2 and Rj 3, does not occur with B. japonicum USDA122, USDA33, Is-1, etc. Nodulation of cv. Hill which carries the Rj 4 gene, does not occur with B. japonicum USDA61, Is-21, etc. while A62-2 which carries a recessive gene rj 1, does not nodulate with almost any of the strains of B. japonicum. Therefore, the B. japonicum strains can be classified into three nodulation types based on the compatibility with these Rj-cultivars, that is, type A strains which effectively nodulated both Rj 2 Rj 3-cultivars and Rj 4-ones, type B strains which did not nodulate the Rj 2 Rj 3-cultivars and type C strains which did not nodulate the Rj 4-cultivars. When the nodulation types of the isolates from nodules of field-grown soybeans were examined, it was suggested that the Rj 2 Rj 3-cultivars and Rj 4-cultivars preferred the type C and type B strains, respectively (Ishizuka et al. 1991).  相似文献   

8.
Cowpea (Vigna unguiculata (L.) Walp.) is one of the most important crops in the north and northeast regions of Brazil, where it is grown under the subsistence regime, mainly because of its adaptation to the local edaphoclimatic conditions. This species is an important legume in Brazil because of its significant nutritional value in the diet of low-income populations. Moreover, it is able to benefit from the process of biological nitrogen fixation, which leads to a significant reduction in production costs. The objective of this research was to evaluate the agronomic efficiency of bacterial strains approved by the Ministry of Agriculture, Livestock and Supply for commercial inoculant production when in symbiosis with cowpea in a Rhodic Eutrudox in Lavras, MG, as well as to identify and verify the efficiency of the native populations that nodulate cowpea. Agronomic efficiency of nitrogen-fixing nodulating bacterial strains (UFLA 03-84, INPA 03-11B, and BR 3267) in symbiosis with cowpea was evaluated in the field. Subsequently, the efficiency and diversity of isolates from the nodules obtained in the field were evaluated under greenhouse conditions. The genetic diversity of the efficient isolates was determined by partial sequencing of the 16S rRNA gene. Grain yields obtained by the inoculation of seeds in the field with the strains were similar to those of the controls without inoculation with and without mineral N addition indicating the existence of efficient native populations. In the native community, we identified isolates with similar or higher efficiency than the strains approved for cowpea inoculation and the control that received mineral N. The isolates subjected to partial sequencing of the 16S rRNA gene were phylogenetically related to the Bradyrhizobium genus.  相似文献   

9.
We investigated the diversity of rhizobia isolated from different indigenous legumes in Flanders (Belgium). A total of 3810 bacterial strains were analysed originating from 43 plant species. Based on rep-PCR clustering, 16S rRNA gene and recA gene sequence analysis, these isolates belonged to Bradyrhizobium, Ensifer (Sinorhizobium), Mesorhizobium and Rhizobium. Of the genera encountered, Rhizobium was the most abundant (62%) and especially the species Rhizobiumleguminosarum, followed by Ensifer (19%), Bradyrhizobium (14%) and finally Mesorhizobium (5%). For two rep-clusters only low similarity values with other genera were found for both the 16S rRNA and recA genes, suggesting that these may represent a new genus with close relationship to Rhodopseudomonas and Bradyrhizobium. Primers for the symbiotic genes nodC and nifH were optimized and a phylogenetic sequence analysis revealed the presence of different symbiovars including genistearum, glycinearum, loti, meliloti, officinalis, trifolii and viciae. Moreover, three new nodC types were assigned to strains originating from Ononis, Robinia and Wisteria, respectively. Discriminant and MANOVA analysis confirmed the correlation of symbiosis genes with certain bacterial genera and less with the host plant. Multiple symbiovars can be present within the same host plant, suggesting the promiscuity of these plants. Moreover, the ecoregion did not contribute to the separation of the bacterial endosymbionts. Our results reveal a large diversity of rhizobia associated with indigenous legumes in Flanders. Most of the legumes harboured more than one rhizobial endosymbiont in their root nodules indicating the importance of including sufficient isolates per plant in diversity studies.  相似文献   

10.
In 1993 and 1994, 12 bacterial isolates were isolated from root nodules of cicer milkvetch (Astragalus cicer). In the tests for nodulation of A. cicer by these bacterial isolates, five were found to form hypertrophic structures, while only two formed true nodules. These true nodules were formed in a sterilized soil system. This system might be able to act as a DNA donor to provide residual DNA to other microbes in the soil. The rhizobial isolates were thought to have lost genetic material crucial to nodulation during the isolation process. This hypothesis was supported by an experiment in which isolate B2 was able to nodulate A. cicer in vermiculite culture after being mixed with heat-killed rhizobia, Rhizobium leguminosarum bv. trifolii and R. loti. The nodulation would not occur in vermiculite culture system without the heat-killed rhizobia. Based on the biochemical data, the B2 and 9462L, which formed true nodules with A. cicer, were closely related. The rhizobia type cultures that nodulate A. cicer include Bradyrhizobium japonicum, Rhizobium leguminosarum bv. trifolii, R. leguminosarum bv. viceae, and R. loti. All of these rhizobia were from different cross-inoculation groups. The B2 and 9462L isolates could only nodulate Medicago sativa, Phaseolus vulgaris, and Melilotus officinalis, but not these species within the genus from which they were isolated: Astragalus. The traditional cross-inoculation group concept obviously does not fit well in the classification of rhizobia associated with Astragalus. The rhizobia isolated from A. cicer can be quite different, and the rhizobia able to renodulate A. cicer also quite diverse. Received: 27 June 1996  相似文献   

11.
Biserrula pelecinus is a pasture legume species new to Australian agriculture. The potential N benefit from B. pelecinus pastures in agricultural systems may not be realised if its symbiotic interactions with Mesorhizobium spp. are not well understood. This study evaluated the symbiotic interactions of four strains of Biserrula root-nodule bacteria (WSM1271, WSM1283, WSM1284, WSM1497) with four genotypes of B. pelecinus (cv. Casbah, 93GRC4, 93ITA33, IFBI1) and with a range of related legumes, including species known to be nodulated by strains of Mesorhizobium loti and other Mesorhizobium spp. Structures of root nodules were studied using light and electron microscopy enabling the ultrastructure of effective and ineffective nodules to be compared. B. pelecinus always formed typical indeterminate, finger-like nodules. The number of bacteroids inside symbiosomes varied between host×strain combinations, however, nodules formed by ineffective associations had well developed peribacteroid membranes and abundant bacteroids. Considerable variation was found in N2-fixing effectiveness of strains isolated from B. pelecinus on the four B. pelecinus genotypes. Strains WSM1271, WSM1284 and WSM1497 nodulated Astragalus membranaceus, only strains WSM1284 and WSM1497 nodulated Astragalus adsurgens. Strain WSM1284 also nodulated Dorycnium rectum, Dorycnium hirsutum, Glycyrrhiza uralensis, Leucaena leucocephala, Lotus edulis, Lotus glaber, Lotus maroccanus, Lotus ornithopodioides, Lotus pedunculatus, Lotus peregrinus, Lotus subbiflorus and Ornithopus sativus. The four strains from B. pelecinus did not nodulate Amorpha fruticosa, Astragalus sinicus, Cicer arietinum, Hedysarum spinosissimum, Lotus parviflorus, Macroptilium atropurpureum or Trifolium lupinaster. M. loti strain SU343 nodulated all four genotypes of B. pelecinus. However, M. loti strain CC829 only nodulated B. pelecinus genotypes 93ITA33 and IFBI1 and the nodules were ineffective. The root nodule isolates from H. spinosissimum (E13 and H4) nodulated B. pelecinus cv. Casbah whereas the commercial inoculant strain for Cicer (CC1192) could not nodulate any genotype of B. pelecinus. These results indicate that strains WSM1271, WSM1283 and WSM1497 isolated originally from B. pelecinus have a specific host range while strain WSM1284 is promiscuous in its capacity to nodulate with a broad range of related species. As B. pelecinus can be nodulated by Mesorhizobium spp. from other agricultural legumes, particularly Lotus, there is an opportunity to utilise this trait in cultivar development.  相似文献   

12.
Several strains of Bradyrhizobium, Mesorhizobium and Sinorhizobium strains were tested for their compatibility with an Australian acacia: Acacia holosericea. All bacterial strains induced some nodule formation on roots. However, the rhizobia which greatly increased the development of seedlings belonged to the Bradyrhizobium genus. The root-knot nematode Meloidogyne javanica, strongly inhibited the symbiosis with most of the rhizobial strains. The rhizobia had no effect on nematode multiplication except for bacterial strain ORS 1020 where the final nematode population was higher than in the control treatment. The hypothesis concerning the interactions between nematodes and the nitrogen fixative process are discussed. Moreover, this investigation underlines the decreasing effect of nematodes on the potential benefits that may result from growing A. holosericea inoculated with selected rhizobial strains.  相似文献   

13.
Bacteria capable of utilising oxamyl as the sole carbon source were isolated from seven different agricultural soils that had previously demonstrated enhanced oxamyl degradation in a soil incubation study. Partial sequencing and alignment of the 16S rRNA gene showed little diversity amongst isolates, with 26 of the 27 isolates demonstrating similarity to the genus Aminobacter. The most common species isolated was Aminobacter aminovorans, while a number of the isolates demonstrated an equal degree of similarity to the species Aminobacter niigataensis and Chelatobacter heintzii. One isolate was identified as Mesorhizobium sp. This is the first time that organisms involved in the degradation of oxamyl have been isolated and identified.  相似文献   

14.
TWenty-six isolates were obtained from nodules of various legume plants (Glycine max, Vigna sinensis, Arachis hypogaea, Desmanthus virgatus, Acacia mangium, Centrosema pascuorum, Pterocarpus indicus, Xylia xylocarpa, and Sesbania rostrata) in Thailand. After confirming their nodulation and nitrogen-fixing abilities, they were identified by 16S rRNA gene analysis as Bradyrhizobium japonicum, Bradyrhizobium elkanii, Rhizobium leguminosarum, Rhizobium gallicum, and Rhizobium galegae. Using these local isolates, the distribution of the activities of both NAD+-dependent (DME: EC 1.1.1.39) and NADP+-dependent (TME: EC 1.1.1.40) malic enzymes was surveyed. The malic enzyme activities were present in all the isolated rhizobia and in other 17 local Bradyrhizobium strains in Thailand. In almost all the rhizobia, the DME activity predominated whereas the TME activity predominated only in the Rhizobium gallicum strains that were major symbionts of Sesbania rostrata. Southern hybridization analysis was performed to survey the distribution of the malic enzyme genes among the local rhizobia, which are similar to those of B. japonicum. DNA probes (ME1 for DME and ME2 for TME) were prepared by polymerase chain reaction (PCR) using degenerated primers from conserved regions of the protein sequences of bacterial malic enzymes. Southern blot analysis with ME1 as a probe showed a single band in about half of the isolates, especially in B. japonicum and R. leguminosarum strains, suggesting the wide distribution of such DME genes among local rhizobia. In contrast, Southern blot analysis with ME2 as a probe detected a single band only in five B. japonicum strains, suggesting that the TME genes, which are similar to those of B. japonicum, would be unique in a group of B. japonicum.  相似文献   

15.
Using a local Algerian cultivar of chickpea, from 9 sites in Eastern Algeria, along a sub-humid to arid gradient, we isolated 60 nodulating isolates, among which 19 were assigned to Mesorhizobium species and 41 to Ensifer meliloti. Trapping revealed great differences among sites for their ability to induce nodules on plant, but no correlation with chemical and physical characterizations of soil samples could be found. Based on 16S rRNA gene sequences, 16S-23S IGS, recA, nodC and nifH sequences, Mesorhizobium isolates were assigned to at least 5 different species, among which one had never been described as nodulating chickpea before. The symbiotic diversity is conversely low, and shared by several species, reflecting horizontal gene transfer. The ability of Mesorhizobium genus to recombine and exchange symbiotic clusters among different species must play a great role in this ability to be associated with chickpea. The question to what extent the symbiotic species would end in this genus is discussed.  相似文献   

16.
The present study was conducted to isolate and characterize rhizobial strains from root nodules of cultivated legumes, i.e. chickpea, mungbean, pea and siratro. Preliminary characterization of these isolates was done on the basis of plant infectivity test, acetylene reduction assay, C-source utilization, phosphate solubilization, phytohormones and polysaccharide production. The plant infectivity test and acetylene reduction assay showed effective root nodule formation by all the isolates on their respective hosts, except for chickpea isolate Ca-18 that failed to infect its original host. All strains showed homology to a typical Rhizobium strain on the basis of growth pattern, C-source utilization and polysaccharide production. The strain Ca-18 was characterized by its phosphate solubilization and indole acetic acid (IAA) production. The genetic relationship of the six rhizobial strains was carried out by random amplified polymorphic DNA (RAPD) including a reference strain of Bradyrhizobium japonicum TAL-102. Analysis conducted with 60 primers discriminated between the strains of Rhizobium and Bradyrhizobium in two different clusters. One of the primers, OPB-5, yielded a unique RAPD pattern for the six strains and well discriminated the non-nodulating chickpea isolate Ca-18 from all the other nodulating rhizobial strains. Isolate Ca-18 showed the least homology of 15% and 18% with Rhizobium and Bradyrhizobium, respectively, and was probably not a (Brady)rhizobium strain. Partial 16S rRNA gene sequence analysis for MN-S, TAL-102 and Ca-18 strains showed 97% homology between MN-S and TAL-102 strains, supporting the view that they were strains of B. japonicum species. The non-infective isolate Ca-18 was 67% different from the other two strains and probably was an Agrobacterium strain.  相似文献   

17.
Rooibos (Aspalathus linearis) has been reported to be nodulated by rhizobia belonging to members of the genus Bradyrhizobium but based solely on slow growth rate on growth media in vitro. Because there is very little information about the rhizobia that nodulate and fix nitrogen in rooibos, the characterization of rhizobial strains and their ability to nodulate A. linearis was investigated in this study. Soils intially collected from the rhizosphere of different Aspalathus populations were used in a baiting experiment to trap rhizobia by rooibos roots. The rhizobia trapped in the nodules were re-isolated and used in Koch’s postulate experiment using the Leonard jar assembly in the glasshouse. The strains that formed on the average between five and 12 indeterminate pink nodules per plant resulted in statistically significant (P = 0.05) increase in shoot and root dry weights. Phylogenetic analysis of the 16S ribosomal RNA sequence of the isolates from the root nodules revealed for the first time that A. linearis is nodulated by different groups of rhizobia belonging to members of both the α-Proteobacteria and the β-Proteobacteria. It was also found that only 2% of the total rhizobia isolated from the root nodules of rooibos were represented by the genus Bradyrhizobium. The finding that rooibos is nodulated by different groups of α-rhizobia and β-rhizobia provides valuable information both in the study of the microbial ecology of rooibos and in the selection of highly efficient nitrogen fixing strains for the commercial cultivation of this indigenous legume.  相似文献   

18.
The genome of Bradyrhizobium japonicum and B. elkanii contains multiple copies of the repeated DNA sequence RSα. A collection of 18 B. japonicum, 4 B. elkanii and 72 other bacterial strains was screened by polymerase chain reaction (PCR) using a pair of primers specific for RSα. Only strains of B. japonicum and B. elkanii gave the predicted amplification product. Restriction analysis of PCR products obtained from different strains of B. japonicum showed that the RSα sequence was generally conserved. The usefulness of RSα as a specific probe for Bradyrhizobium strains capable of nodulating soybean was also demonstrated. Received: 11 May 1995  相似文献   

19.
We have evaluated the genetic diversity and phylogeny of alfalfa rhizobia, originating from different types of soils in Serbia and their ability to establish an effective symbiosis with alfalfa (Medicago sativa L.). A collection of 65 strains isolated from root nodules of alfalfa were characterized by rep-PCR analysis, partial and complete 16S rDNA gene and recA gene sequencing, as well as atpD gene sequencing and DNA–DNA hybridizations. The results of the sequence analyses revealed that Sinorhizobium meliloti is the dominant species in alfalfa nodules. Only one strain was identified as Sinorhizobium medicae, two strains as Rhizobium tibeticum and one strain as Rhizobium sp. Despite the fact that the majority of strains were identified as S. meliloti, a high genetic diversity at strain level was detected. Almost all isolates shared the ability to nodulate and fix nitrogen with M. sativa, except 11 of them, which were incapable of fixing nitrogen with this species. About 50% of the isolates showed values of symbiotic effectiveness (SE) above 50%, while 10% of the strains were highly effective with SE values above 70%. Some of the strains which were highly effective in nitrogen fixation at the same time could intensively solubilize phosphates, offering a possibility for multipurpose inoculum development. This was the first genetic study of rhizobia isolated from this region and also the first report of natural presence of R. tibeticum in root nodules of M. sativa.  相似文献   

20.
Thirty-nine endophytic bacterial strains were isolated from the nodule of Lespedeza sp. grown in two different locations of South Korea. All strains were checked for their plant growth promoting (PGP) abilities under in vitro conditions. Most of the isolates showed multiple PGP activity, i.e., indole acetic acid production, ACC deaminase activity, siderophore production, and phosphate solubilization. The strains were identified by using 16S rRNA gene sequence analysis as belonging to Alphaproteobacteria, Betaproteobacteria, Actinobacteria, and Firmicutes phylum with nine different genera Arthrobacter, Bacillus, Bradyrhizobium, Burkholderia, Dyella, Methylobacterium, Microbacterium, Rhizobium, and Staphylococcus. Gene nodA amplification showed positive results only for strains from Bradyrhizobium and Rhizobium genera. The strains from Bradyrhizobium and Rhizobium genera enhanced plant growth, nodulation, and acetylene reduction activity when inoculated on Vigna unguiculata L. (cowpea), whereas other strains did not induce nodule formation but enhanced plant growth. Herbaceous legume Lespedeza sp. formed root nodules with diverse bacterial group, and probably, these bacteria can be used for stimulating plant growth.  相似文献   

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