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Alfalfa-Siberian wild rye intercropping is the predominant cropping system used to produce forage in China. In this study, the effects of intercropping and intercropping-rhizobial inoculation on soil enzyme activities, microbial biomass and bacterial community composition in the rhizosphere were examined. In both treatments, the yield of alfalfa, microbial biomass and activities of soil urease, invertase and alkaline phosphatase in the alfalfa rhizosphere were markedly increased, whereas there was a slight increase in the yield of Siberian wild rye, few impacts on soil microbial biomass, and decreased enzyme activities (except for urease) in the Siberian wild rye rhizosphere. Terminal restriction fragment length polymorphism (T-RFLP) of 16S rRNA genes indicated that Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Deltaproteobacteria, Firmicutes, Actinobacteria and Bacteroidetes were the major bacterial groups in the rhizosphere of both plants. However, intercropping and rhizobial inoculation induced some shifts in the relative abundance of them. Nitrosomonas and Nitrosospira groups were detected in all treatments by the T-RFLP patterns of ammonia monooxygenase subunit A (amoA) gene, but the relative abundance of Nitrosomonas increased and that of Nitrosospira decreased in the intercropping-rhizobial inoculation treatment. Both treatments tended to increase the diversity of amoA. Conclusively, the two treatments clearly affected soil microbial composition and soil enzyme activities, which might be reflected in changes in yield.

A yellow-coloured bacterium, T41 T , was isolated from a soil sample of a subtropical rainforest in Nepal. Cells were Gram-reaction-positive, aerobic, non-motile, short rods. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain formed a cluster with Terrimonas ferruginea, Terrimonas lutea, Niabella soli, Flavisolibacter ginsengiterrae, Flavisolibacter ginsengisoli, Niastella yeongjuensis and Niastella koreensis in the phylum Bacteroidetes. The strain showed the highest sequence similarity to the type strain of Terrimonas lutea (93.2 %). The major isoprenoid quinone was MK-7 and the predominant cellular fatty acids (.10 %) were iso-15 : 0 (33.8 %), iso-15 : 1 G (13.3 %) and iso-17 : 0 3-OH (12.9 %). The DNA G+C content was 48.1 mol%. On the basis of phenotypic and phylogenetic data and genomic distinctiveness, strain T41 T represents a novel species in a new genus in the phylum Bacteroidetes, for which the name Flavihumibacter petaseus gen. nov., sp. nov. is proposed. The type strain of Flavihumibacter petaseus is strain T41 T (5CGMCC 1.7723 T 5NBRC 106054 T ).During the course of a study on the culturable bacterial community in a subtropical rainforest soil sample from Nepal (27 u 349 N 84 u 319 E), a novel yellow-pigmented bacterium, designated strain T41 T , was isolated. On the basis of phylogenetic analysis, strain T41 T formed a distinct cluster closely related to members of the genera Terrimonas, Flavisolibacter, Niabella and Niastella of the phylum Bacteroidetes. The polyphasic phenotypic and genotypic characterization of strain T41 T is described in this report.The soil sample was serially diluted with 0.85 % NaCl (w/v) and the dilutions were plated onto modified R2A agar containing (l 21 ) 0.5 g glucose, 0.5 g casein hydrolysate, 0.5 g soluble starch, 0.5 g peptone, 0.5 g yeast extract, 0.3 g K 2 HPO 4 , 0.05 g MgSO 4 . 7H 2 O and 17 g agar (pH 7.2). The plates were incubated at 28 u C for 7 days. Single colonies were purified by transferring them onto new R2A plates and were incubated once again. Purified colonies were maintained as glycerol suspensions (20 %, w/v) at 270 u C.The Gram reaction was determined using the non-staining method, as described by Buck (1982). Cell morphology was observed under a light microscope (Nikon) at 61000, with cells grown for 3 days at 28 u C on R2A agar. Motility was examined using the hanging-drop technique with fresh cells in R2A broth. Catalase activity was determined by bubble production in 3 % (v/v) H 2 O 2 , and oxidase activity was determined by daubing cultures with 1 % (w/v) N,Ndimethyl p-phenylenediamine (Yoon & Im, 2007). Carbonsource utilization was assessed using a liquid medium containing (l 21 ) 1 g (NH 4 ) 2 HPO 4 , 0.3 g K 2 HPO 4 , 0.05 g MgSO 4 . 7H 2 O and 0.2 g yeast extract (pH 7.2). Carbon substrates were added at a concentration of 0.5 % (w/v). The culture was incubated under 28 u C and, after 3 days, the result was compared using a spectrophotometer. Acid production was investigated by adding bromothymol blue as an i...

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