Inoculation with Phosphate Solubilizing Mesorhizobium Strains Improves the Performance of Chickpea (Cicer aritenium L.) Under Phosphorus Deficiency

The use of phosphate-solubilising bacteria as inoculants increases plant phosphorus (P) uptake and thus crop yield. Strains from the genus Mesorhizobium are among the most powerful phosphate solubilizing microorganisms. In order to study efficiency in P uptake and N₂ fixation in chickpea (Cicer aritenium), forty-two rhizobia strains natively from Tunisian soils were studied in symbiosis with the chickpea variety “Béja1” which is frequently cultivated in Tunisia. Plants were inoculated separately with these strains under controlled conditions in perlite under two sources of P i.e. soluble (KH₂PO₄) and insoluble P (Ca₂HPO₄). At flowering stage, growth, nodulation, P uptake and N₂ fixation were assessed in all symbiotic combinations. The results showed that the S27 strain efficiently mobilized P into plants, observed as a significant increase of plant P content when insoluble P (Ca₂HPO₄) was supplied to the soil. This was associated with a significant increase in plant biomass, nodule number and N content under insoluble P conditions. Additionally, inoculation with the Mesorhizobium strain S27 significantly increased the root acid phosphatase activity under insoluble P. This study also shows significant correlations found between plant P content and acid phosphatase activity under low P conditions which may highlight the contribution of acid phosphatases in increasing P use efficiency. A field experiment also showed that most of the chickpea analyzed parameters were improved when plants inoculated with two selected rhizobia strains (S26 and S27) and supplied with P2O5. Overall, these findings postulate that rhizobial inoculation should not only be based on the effectiveness of strains regarding N fixation, but also to other traits such as P solubilisation potential.     

Study on the Effects of Organic and Inorganic Nitrogen Fertilizer on Yield,Yield Components,and Nodulation State of Chickpea (Cicer arietinum L.)

To study the effects of organic and inorganic nitrogen (N) on yield and nodulation of chickpea (Cicer arietinum L.) cv. ILC 482, a spilt-plot experiment based on randomized complete block design with four replications was conducted in 2008 at the experimental farm of the Agriculture Faculty, University of Mohaghegh, Ardabili. Experimental factors were inorganic N fertilizer at four levels (0, 50, 75, and 100 kg ha^?1) in the main plots that applied in the urea form, and two levels of inoculation with Rhizobium bacteria (with and without inoculation) as subplots. Nitrogen application and Rh. inoculation continued to have positive effects on yield and its attributes. The greatest plant height, number of primary and secondary branches, number of pods per plant, number of filled and unfilled pods per plant, number of grains per plant, grain yield, and biological yield were obtained from the greatest level of N fertilizer (100 kg urea ha^?1) and Rh. inoculation. Application of 75 and 100 kg ha^?1 urea showed no significant difference in these traits. Furthermore, the greatest rate of N usage (100 kg urea ha^?1) adversely inhibited nodulation of chickpea. Number and dry weight of nodules per plant decreased significantly with increasing N application rate. The lowest values of these traits recorded in application of 100 kg ha^?1 urea. Results indicated that application of suitable amounts of N fertilizer (i.e., between 50 and 75 kg urea ha^?1) as starter can be beneficial to improve nodulation, growth, and final yield of inoculated chickpea plants.     

Compatibility of Mesorhizobium sp. Cicer with seed treatment of fungicide and insecticide in chickpea

This investigation was undertaken to study the compatibility of Mesorhizobium sp. Cicer with captan (fungicide) and chlorpyrifos (insecticide) for growth, symbiotic parameters and yield in chickpea. In an in vitro experiment, a significant reduction in the number of viable mesorhizobia was observed in Mesorhizobium sp. Cicer treated chickpea seeds at the recommended doses of captan (3 g kg^?1 seed) and chlorpyrifos (10 ml kg^?1 seed) after 4 h storage at 4°C, and further reduction was seen after 8–16 h contact with Mesorhizobium. The results showed that captan was more toxic than chlorpyrifos. In field experiments, improved growth and symbiotic parameters (plant height, dry weight of shoot, nodulation, leghaemoglobin content, chlorophyll content and nitrogen content) and a reduction in per cent damaged by termites and diseases were observed in the Mesorhizobium alone treatment compared with the uninoculated control. Grain yield was increased significantly in treatments with Mesorhizobium alone or in a mixture with fungicide and insecticide (captan and chlorpyrifos) compared with the control treatment. It is evident that chemically treated seeds should always be sown as soon as possible after inoculation. Recommended rates of captan and chlorpyrifos application with Mesorhizobium inoculant as a seed treatment was innocuous to chickpea–Mesorhizobium symbiosis.     

Evaluation of plant growth promoting activities of microbial strains and their effect on growth and yield of chickpea (Cicer arietinum L.) in India

The aims of our study were to enhance growth, yield and disease control of chickpea by various combinations of microbial strains (Mesorhizobium, Azotobacter chroococcum, Pseudomonas aeruginosa and Trichoderma harzianum). Pseudomonas and Trichoderma showed positive IAA (indole-3-acetic acid) production, phosphate solubilisation and antagonistic activities against Fusarium oxysporum and Rhizoctonia solani as compared to other strains. In two year investigations, tetra-inoculants have shown significant growth attributes, yield and phytopathogen growth inhibition followed by tri-inoculants than control. Therefore, tetra-inoculants (Mesorhizobium-Azotobacter-Pseudomonas-Trichoderma) may be used as efficient biofertilizer and bio-control agent for chickpea production (Cicer arietinum L.) in eastern Uttar Pradesh.     

The Symbiotic Performance and Plant Nutrient Uptake of Certain Nationally Registered Chickpea (Cicer Arietinum L.) Cultivars of Turkey

An experiment was conducted under greenhouse conditions to test the symbiotic performance and plant nutrient uptake of the twelve nationally registered chickpea cultivars (‘Çak?r’, ‘I??k-05’, ‘Can?tez-87’, ‘Hisar’, ‘Ya?a-05’, ‘Azkan’, ‘Küsmen-99’, ‘Gökçe’, ‘Damla-89’, ‘Diyar-95’, ‘Aziziye-94’, and ‘?zmir-92’) in Turkey. Inoculation with Mesorhizobium ciceri increased the average nodule number by 687%, nodule weight by 257%, plant height by 6%, shoot dry weight by 12%, root dry weight by 21%, chlorophyll content by 4.2%, nitogen (N)% by 7.9%, and total N by 22.7%. Averaged across chickpea cultivars, inoculation also significantly increased sulfur (S) by 14.4%, phosphorus (P) by 1.9%, magnesium (Mg) by 13.8%, potassium (K) by 6.2%, calcium (Ca) by 17.4%, copper (Cu) by 4.5%, iron (Fe) by 16.5%, manganese (Mn) by 10.9% and zinc (Zn) uptake by 9.4%. The macro- and micronutrient uptake of cultivars significantly correlated with their nitrogen content and the magnitude of response to inoculation in relation to nodulation, plant growth, nitrogen fixation, and nutrient uptake significantly varied among cultivars. Based on the amount of fixed N and plant nutrient uptake, ‘Azkan’, ‘Aziziye-94’, ‘Küsmen-99’, ‘Diyar-95’, and ‘Hisar’ were the genotypes with the most positive response to inoculation. Our data showed that nodulation, nitrogen fixation, plant dry matter production, and macro- and micronutrient uptake of the inoculated chickpea can be improved by selecting the best compatible cultivar.     

Symbiotic effectiveness of streptomycin-resistant Rhizobium spp. mutants of chickpea (Cicer arietinum L.)

Summary Antibiotic-resistant Rhizobium spp. strains have been used in ecological studies of legumerhizobia symbiosis. It has been suggested that in the course of acquiring resistance against high doses of antibiotics, rhizobia might lose their symbiotic effectiveness. Evidence both for and against this argument has been presented (Kremer and Peterson 1982; Materon and Hagedron 1983). This communication reports our experience with streptomycin-resistant (Str⁺) mutants of chickpea Rhizobium spp. strains. Parent strains were used as controls.Research paper No. 5233 from the Experiment Station, G.B.P.U.A.&T. Pantnagar, Nainital     

The extent of embryo and endosperm growth following interspecific hybridization between Cicer arietinum L. and related annual wild species

In vivo interspecific pollinations were performed and immature seed development investigated by histological methods in order to study crossability barrier(s) in Cicer L. species wide hybridization. Seven of the eight wild annual Cicer species, belonging to the secondary and tertiary gene pools, were used in reciprocal crosses with the cultivated chickpea. It was confirmed that the zygote was formed in all interspecific crosses. The embryos showed continued and retarded growth at different rate in various crosses, but eventually aborted at an early pro-embryo stage in all crosses except C. arietinum L. ×C. echinospermum Dav. Reciprocal cross differences were observed in early embryo growth rate and could have implications in obtaining hybrids. This study further emphasizes the necessity for developing appropriate and efficient in vitro procedures for rescuing immature globular hybrid pro-embryos, which will make the wild Cicer gene resources amenable to chickpea improvement.     

Displacement of native rhizobia nodulating chickpea (Cicer arietinum L.) by an inoculant strain through soil solarization

Summary Soil solarization greatly reduced the native chickpea Rhizobium population. With inoculation, it was possible to increase the population of the Rhizobium in solarized plots. In the 1st year, 47% nodulation was obtained with chickpea inoculant strain IC 59 when introduced with a cereal crop 2 weeks after the soil solarization and having a native Rhizobium count of <10 g^-1 soil, and only 13% when introduced 16 weeks after solarization at the time the chickpeas were sown, with 2.0×10² native rhizobia g^-1 soil. In the non-solarized plots inoculated with 5.6×10³ native rhizobia g^-1 soil, only 6% nodulation was obtained with the inoculant. In the succeeding year, non-inoculated chickpea was grown on the same plots without any solarization or Rhizobium inoculation. The treatment that showed good establishment of the inoculant strain in year 1 formed 68% inoculant nodules. Other treatments indicated a further reduction in inoculant success, from 1%–13% to 1%–9%. Soil solarization thus allowed an inoculant strain to successfully displace the high native population in the field and can serve as a research tool to compare strains in the field, irrespective of competitive ability. In year 1, Rhizobium inoculation of chickpea gave increased nodulation and increased plant growth 20 and 51 days after sowing, and increased dry matter, grain yield, and grain protein yield at maturity. These beneficial effects of inoculation on plant growth and yield were not measured in the 2nd year.Submitted as Journal Article No. JA 945 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Andhra Pradesh 502 324, India     

Influence of Vermicompost Fertilizer and Water Deficit Stress on Morpho-Physiological Features of Chickpea (Cicer arietinum L. cv. karaj)

One goal in the face of deficit water conditions is to increase growth and yield. Agro-industrial production frequently causes environmental pollution by using chemical fertilizers. In recent decades, bio-fertilizers such as vermicompost have been used as a safe alternative to chemical fertilizer. The present study considered the response of the chickpea to different combinations of vermicompost and water deficit stress in a greenhouse environment. Plant response was determined by measuring a range of morpho-physiologic parameters. The treatments were addition of 0%, 10%, 20%, and 30% of vermicompost to soil, and water deficit stress at the following levels: non-stress (100% of field capacity), moderate water stress (75% of field capacity), and severe water stress (25% of field capacity). The results showed that vermicompost had a significant effect on all traits under stress and non-stress conditions. The vermicompost treatments under non-stress conditions significantly increased plant height, number of pods, leaf area, stem and leaf dry weight, pod dry weight, chlorophyll a, carotenoid, total chlorophyll content, CO₂ assimilation rate, internal CO₂ concentration, and water-use efficiency over that of the control condition. The addition of 30% vermicompost under moderate and severe water stress conditions significantly increased plant height, number of pods, leaf area, leaf dry weight, carotenoids, and water-use efficiency over that of the control level. This study confirmed that vermicompost improved the morphological features, soil biological activity, and quality of the chickpea, but did not positively influence the physiological features under moderate and severe water deficit stress.     

Genetic relationships among perennial and annual Cicer species growing in Turkey as revealed by allozymes

Allozyme polymorphisms were used to assess genetic variation and relationships among ten Cicer species (annuals and perennials) growing in Turkey. Using seven enzyme systems, 12 putative scorable loci were detected and surveyed for polymorphism in an accession collection including wild and cultivated forms. Variation was generally low within accessions and species, but common between species. Cluster analysis based on the pairwise genetic distance coefficients among accessions and species using UPGMA revealed two species clusters; one includes three perennials (C. montbretii, C. isauricum and C. anatolicum) and the other contains six annuals (C. pinnatifidum, C. bijugum, C. judaicum, C. echinospermum, C. reticulatum and C. arietinum) and one perennial species (C.incisum). Grouping obtained in allozyme analysis appears to be consistent with the classification these species into three sections. However, contrary to relationships obtained in previous studies, three perennial species from section Polycicer were relatively distant to the group containing annuals. One perennial species, C. incisum from section Chamaecicer, clustered with annuals showing a close similarity. The grouping of six annual species was consistent with the previous reports of relationships. The relationships deduced between perennials and annuals appear to shed light on the evolution of annual habit from perennial habit.     

Topography of the Cotyledon Surfaces and Adjoining Seed Coat of Chickpea (Cicer arietinum L.) Genotypes Differing in Milling Performance

Milling of pulse seeds generally refers to dehulling (decortication or seed coat removal) and splitting (division of the two cotyledons) to produce split seeds, known as dhal. Reduction of whole seeds or dhal to flour, in comparison, is generally termed “grinding” for pulses. Many pulses are consumed as dhal, including desi chickpea (Cicer arietinum L.), faba bean (Vicia faba L.), lentil (Lens culinaris L.), field pea (Pisum sativum L.), pigeon pea (Cajanus cajan L.), mungbean (Vigna radiata L.), black gram (Vigna mungo L.), and hyacinth bean (Lablab purpureus L.). Hence, ease‐of‐milling is an important quality attribute of pulse species that are commonly dehulled or split prior to consumption. Seed structure and the surface topography at the junctions between seed coat and cotyledons have the potential to influence the varietal differences observed in the ease of milling. The epicuticular wax surfaces of six genotypes of chickpea differing in ease of milling were examined by scanning electron microscopy to evaluate whether the physical attributes of seed coat and cotyledon surfaces could be involved in adhesion. Differing epicuticular wax patterns were observed for each of the six genotypes. The possible roles these patterns play in genotypic differences in ease of milling are discussed.     

Effect of inoculum rate on the performance of chickpea (Cicer arietinum L.) Rhizobium strains in the field

Summary The influence of three inoculum rates on the performance of three chickpea (Cicer arietinum L.) Rhizobium strains was examined in the field on a Mollisol soil. Increasing amounts of inoculum improved the performance of the strains. A normal dose (10⁴ cells per seed) applied at different intervals gave non-significant increases in nodulation, nitrogenase activity (acetylene reduction assay), nitrogen uptake and grain yield. A ten-fold increase in inoculum increased nodule number, shoot dry weight, nitrogenase activity (ARA) and grain yield, but increases over the control were significant only for nodule dry weight and nitrogen uptake by shoot and grain. The highest level of inoculum (100 × normal) significantly increased nodule dry weight, grain yield, total nitrogenase activity (ARA) and nitrogen uptake by shoot and grain. Strain TAL 620 was more effective than the other two. Combined nitrogen (60 kg N ha^–1) suppressed nodulation and nitrogenase activity (ARA).Research paper No. 4345 from the Experiment Station, G. B. P. U. A. & T., Pantnagar, Nainital, U. P.     

Differential responses of chickpea (Cicer arietinum L.) — Rhizobium combinations to saline soil conditions

Summary Chickpea cultivars (Cicer arietinum L.) and their symbiosis with specific strains of Rhizobium spp. were examined under salt stress. The growth of rhizobia declined with NaCl concentrations increasing from 0.01 to 2% (w : v). Two Rhizobium spp. strains (F-75 and KG 31) tolerated 1.5% NaCl. Of the 10 chickpea cultivars examined, only three (Pusa 312, Pusa 212, and Pusa 240) germinated at 1.5% NaCl. The chickpea — Rhizobium spp. symbiosis was examined in the field, with soil varying in salinity from electrical conductivity (EC) 4.5 to EC 5.2 dSm^-1, to identify combinations giving satisfactory yields. Significant interactions between strains and cultivars caused differential yields of nodules, dry matter, and grain. Four chickpea — Rhizobium spp. combinations, Pusa 240 and F-75 (660 kg ha^-1), Pusa 240 and IC 76 (440 kg ha^-1), Pusa 240 and KG 31 (390 kg ha^-1), and Pusa 312 and KG 31 (380 kg ha^-1), produced significantly higher grain yields in saline soil.     

Synergistic effect of bio-inoculants on yield,nodulation and nutrient uptake of chickpea (Cicer arietinum L) under rainfed conditions

The use of efficient bio-inoculants in chickpea is the best way to increase crop productivity under rainfed conditions. To assess the combined effect of bio-inoculants on crop yield, field experiments were conducted during Rabi seasons at Research Station, Punjab Agricultural University, Ballowal Saunkhri, Punjab, India. The application of different bio-inoculants significantly improved number of pods, grain and straw yield of chickpea over the un-inoculated treatment. The combined application of Rhizobium + PSB?+?AM fungi?+?azotobactor inoculums as seed treatment with 75% of recommended phosphorus produced highest grain yield. The nodule count, nodule weight, per cent root colonization of AM fungi and different enzymes activities in soil were also highest in combined bio-inoculants treatment. The present study concluded that combined application of bio-inoculants (Rhizobium, PSB, AM fungi and azotobactor) can save 25% of recommended phosphorus by sustaining the crop yield and improving the soil health.     

Target region amplification polymorphism (TRAP) for assessing genetic diversity and marker-trait associations in chickpea (Cicer arietinum L.) germplasm

The effective utilization of crop diversity held in genebanks depends on our knowledge of useful traits and available markers associated with the target traits. Target region amplification polymorphism (TRAP) was used to evaluate the genetic diversity and underlying relationships among 263 accessions of chickpea landraces maintained by the USDA-ARS Western Regional Plant Introduction Station in Pullman, WA, USA. Two-hundred sixty-two TRAP markers were amplified by eight primer combinations. Altogether, 110 (42 %) markers were polymorphic, the other 152 (58 %) displayed no variation. These polymorphic markers revealed important differences among the accessions, with an estimated, mean pair-wise genetic distance of 25.82 %, ranging from 2.8 to 50.0 %. Genetic distance analysis divided the accessions into two major groups, with 113 and 150 accessions each, and substantial association between molecular diversity and geographic origin was evident. Bayesian analysis of population structure revealed two groups (K = 2) with evidence for six sub-groups. Additionally, the population structure of a subset of 110 lines was determined (K = 3) for testing marker-trait associations (MTAs). Phenotypic traits included the concentrations of protein and nine mineral elements in the seeds. Two MTAs were significant (p < 0.01) for concentrations of Ca and K, and three MTAs were significant for Cu and Ni concentrations. The results indicate that this population is useful for genome-wide association studies on other economic traits given the level of genetic diversity uncovered and the marker-trait associations in seed minerals discovered.     

Assessment of genetic diversity, and phylogenetic relationships based on ribosomal DNA repeat unit length variation and Internal Transcribed Spacer (ITS) sequences in chickpea (Cicer arietinum) cultivars and its wild species

Repeat unit length variation and internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA were used to assess genetic diversity, and phylogenetic relationships in chickpea (C. arietinum) cultivars, and its related wild species. Total genomic DNAs of 76 accessions of 10 Cicer species, belonging to three sections of the genus, were restricted with seven enzymes and the restriction fragments were hybridized to heterologous ribosomal clones of wheat pTa71 and Vicia faba probes Ver 6-5 and Ver18-6. A single repeat unit length class of 11.4 kb or 10.5 kb was recognized across Cicer accessions with pTa71. The intraspecific variation was negligible in those species where more than one accession was studied, except the four C. judaicum accessions, which were different from the rest. EcoRI and DraI digests gave two and one-two fragments, respectively. All the accessions produced three and three-five bands with BamHI and SacI, respectively. Both the accessions of C. yamashitae differed in their rDNA repeat unit length as well as restriction site variation. Maximum likelihood tree with rDNA RFLP recognized five clades which were more or less congruent with the previous data. Length of ITS-1 region was more variable (235–239 bp) than the ITS-2 region (212–213 bp). Cladistic analysis of ITS data revealed two major clades, clade I consisting of C. arietinum, C. reticulatum and C. echinospermum, and clade II comprised of C. judaicum, C. chorassanicum, C. bijugum and C. cuneatum. C. microphyllum grouped with the above four species. C. pinnatifidum was present as a separate branch. C. yamashitae emerged as the most distinct species.     

Effect of irrigation and biofertilizer on water use,nodulation, growth and yield of chickpea (Cicer arietinum L.)

The field experiment studied the effect of irrigation [irrigation 15 days before sowing (DBS), irrigation 15 DBS + rice straw mulch, irrigation 7 DBS and irrigation 7 DBS + one irrigation at flower initiation] and biofertilizers [no biofertilizer (control), Rhizobium inoculation and Rhizobium inoculation + phosphate-solubilizing bacteria (PSB)] on chickpea growth. In mulch treatment, paddy straw mulch was applied at 4 t ha^?1 one day after pre-sowing irrigation and was retained until sowing. Pre-sowing irrigation at 15 DBS showed 28.7 and 30.0% less plant stand than irrigation applied 15 DBS + straw mulch and irrigation applied 7 DBS, respectively. Nodulation was significantly higher with irrigation 15 DBS + mulch and irrigation 7 DBS than with irrigation applied 15 DBS. The grain yield was 16.6, 20.3 and 44.0% higher in irrigation 15 DBS + mulch, irrigation 7 DBS and irrigation 7 DBS + irrigation at flowering treatments, respectively, over irrigation at 15 DBS. Rhizobium inoculation significantly improved the number of nodules and nodule dry weight compared with no treatment. Grain yield was significantly higher with Rhizobium than in untreated plots. Water use efficiency was highest when irrigation was applied 7 DBS.     

The diversity of rhizobia nodulating chickpea (Cicer arietinum) under water deficiency as a source of more efficient inoculants

Chickpea is an important pulse crop grown mainly in the arid and semi-arid regions. The effect of water deficiency on nodulation, biomass production, and competition for nodule occupancy was evaluated in three different soils with two chickpea cultivars, Amdoun I and Chetoui. Two watering regimes were considered; a control that was irrigated three times per week and a water-deficient treatment that was irrigated only one time a week. Results showed that water deficiency significantly decreased the nodule number and the shoot dry weight for both cultivars. Root-nodule bacteria were isolated and characterized by PCR-RFLP of 16S rDNA and nifD-K intergenic spacer. The results show that water deficiency affects the diversity of nodulating rhizobia. The nodulation by Mesorhizobium mediterraneum was reduced while inefficient nodulation by Ensifer meliloti was favoured. In both treatments, chickpea was preferentially nodulated by nifD-K type N6. Analysis for NaCl tolerance showed that most of rhizobia nodulating chickpea under water deficiency are NaCl tolerant. Inoculation with the selected salt-tolerant strain of M. mediterraneum LILM10 increased significantly nodule number and grain yield in the field.     

Tolerance of chickpea (Cicer arietinum L.) lines to root-knot nematode, Meloidogyne javanica (Treub) Chitwood

The root-knot nematode, Meloidogyne javanica (Treub) Chitwood is an important parasite of chickpea (Cicer arietinum L.). Four chickpea genotypes were evaluated for tolerance to M. javanica in naturally infested fields at three locations. Each genotype was evaluated for number of galls, gall size, root area covered with galls and number of egg masses produced. All the cultivars were susceptible or highly susceptible. Seed yield, weight of 100 undamaged seeds, total dry matter and plant height were compared with checks. Chickpea cultivar Annigeri and a local check were used as nematode susceptible checks in all locations. The four promising nematode tolerant genotypes produced significantly greater yield and total dry matter than the checks in fields naturally infested with M. javanica at three locations. These M. javanica tolerant lines represent new germplasm and they are available in the chickpea genebank at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) bearing the identification numbers ICC 8932, ICC 11152, ICCV 90043 and ICCC 42.     

Impact of single and co-inoculations with Rhizobial and PGPR isolates on chickpea (Cicer arietinum) in cereal-growing zone soil

Strains isolated from chickpea (Cicer arietinum L.) rhizospheric soil from selected sites in Algeria were screened for their plant-growth-promoting potential, for indole acetic acid production and P solubilization ability. Then, we selected native rhizobial strains with high nitrogen-fixing potential. On the basis of their efficiency under controlled conditions, two plant-growth-promoting rhizobacteria (PGPR) isolates and three nodulating bacteria were selected. Then, the effect of single PGPR isolates inoculation was compared to their combination with rhizobial inoculants on plant growth, on native cereal-growing soils under greenhouse conditions. No effects were observed on chickpea yield by using rhizobial inoculation alone, nor by PGPR-rhizobial co-inoculation on two soils presenting weak and no nodulation pattern in natural conditions. Only PGPR inoculation improved growth of plants on soil with no nodulation pattern. These findings emphasized inoculation on native soils at a little scale before large assays on field because no one could predict inocula behavior with native soil microflora.