The aims of the present work were to isolate and characterize fungal endophytic communities associated with healthy wheat (Triticum aestivum L.) plants, collected from the North China. Segregated endophytes were screened for their PGP traits, abiotic stresses (heavy metals, salinity, drought, and temperature), and antibiotic sensitivity. A total of 16 endophytic fungi were isolated using the culture-dependent approach from different tissue parts of wheat plants. Based upon their internal transcribed spacer (ITS) rDNA gene sequencing, 15 out of 16 isolates were selected for further analysis. In the contemporary investigation, a number of the tested endophytes exhibited fairly good 1-aminocyclopropane-1-carboxylic acid deaminase (ACCD) (0.03±0.011 to 1.43±0.01 µmol α-KB mg−1 protein hr−1), indole acetic acid (IAA) (1.125±0.04 to36.12±0.004µgml−1), and phosphate solubilizing index (PSI) (2.08±0.03to5.16±0.36) activities. More than 30% isolates gave positive result for siderophore and ammonia tests, whereas all exhibited catalase activity but only 2 (582PDA1 and 582PDA11) produced hydrogen cyanide. Trichoderma strains showed salt, heavy metals, and drought tolerance at high levels and also exhibited resistance to all the tested antibiotics. Strain 582PDA4 was found to be the most temperature (55°C) tolerant isolate. The findings of this study indicated that the microbial endophytes isolated from wheat plants possessing a crucial function to improve plant growth could be utilized as biofertilizers or bioagents to establish a sustainable crop production system.

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Two nifH gene-harbouring bacterial strains were isolated from rhizospheres of different vegetable plants grown in different regions of northern PR China. The two strains possessed almost identical 16S rRNA gene sequences. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between the two strains were 99.21 and 93.6% respectively, suggesting they belong to one species. Based on 16S rRNA gene phylogeny, the two strains were clustered together with Paenibacillus rhizophilus 7197T, Paenibacillus sabinae T27T and Paenibacillus forsythiae T98T, but on a separate branch. Novelty of the species was confirmed by ANI and dDDH comparisons between the type strain 7124T and its closest relatives, since the obtained values were considerably below the proposed thresholds for the species delineation. The genome size of strain 7124T was 5.40 Mb, comprising 5050 predicted genes with a DNA G+C content of 52.3 mol%. The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unidentified lipids. The major cellular fatty acids were anteiso-C15  :  0 (52.9%) and C16  :  0 (23.4 %). Menaquinone-7 was reported as the major respiratory quinone. The diamino acid in the cell-wall peptidoglycan was found to be meso-diaminopimelic acid. Based on phylogenetic, genomic, chemotaxonomic and phenotypic data, the two isolates are considered to represent a novel species of the genus Paenibacillus , for which the name Paenibacillus apii sp. nov. is proposed, with 7124T (=DSM 103172T=CGMCC 1.15689T) as type strain.

A novel Gram-stain-negative, aerobic, rod-shaped and indole acetic acid-producing strain, designated 7209-2T, was isolated from rhizosphere of rape (Brassica napus L.) grown in the Yakeshi City, Inner Mongolia, PR China. The 16S rRNA gene sequence analysis indicated that strain 7209-2T belongs to the genus Rhizobium and is closely related to Rhizobium rosettiformans W3T, Rhizobium ipomoeae shin9-1T and Rhizobium wuzhouense W44T with sequence similarities of 98.2, 98.1 and 97.9 %, respectively. Phylogenetic analysis based on concatenated housekeeping recA and atpD gene sequences showed that strain 7209-2T formed a group together with R. wuzhouense W44T and R. rosettiformans W3T, with sequences similarities of 92.6 and 91.1 %, respectively. The genome size of strain 7209-2T was 5.25 Mb, comprising 5027 predicted genes with a DNA G+C content of 61.2 mol%. The average nucleotide identity and digital DNA–DNA hybridization comparisons among 7209-2T and reference strains for the most closely related species showed values below the accepted threshold for species discrimination. The major fatty acids of strain 7209-2T were summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c) and summed feature 2 (C12 : 0 aldehyde and/or unknown 10.953) . The major polar lipids were found to consist of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and an unidentified aminophospholipid. The predominant ubiquinone was identified as quinone 10. Based on all the above results, strain 7209-2T represents a novel species of the genus Rhizobium , for which the name Rhizobium rhizophilum sp. nov. is proposed with 7209-2T (=CGMCC 1.15691T=DSM 103161T) as the type strain.

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