[Effects of three Bacillus strains on growth promoting and rhizosphere soil microflora of tomato.].

The effects of Bacillus Bs10, Ba12 and Bl10 on tomato growth and soil rhizosphere microorganisms were determined by Petri dish germination test and pot experiments. The results showed that Bs10, Ba12 and Bl10 exhibited remarkable promoting effect on the length of hypocotyl and radical, as well as the growth of plants. The length, surface area and volume of tomato roots increased significantly after treatment with Bacillus stains, the numbers and proportions of soil bacteria also increased markedly, while those of soil fungi decreased.

[Effects and mechanism of two Streptomyces strains on promoting plant growth and increasing grain yield of maize].

This paper was mainly to explore the effects of two Streptomyces strains (S. roche D74 and S. pactum Act12) and their mixed actinomycetes agent on maize growth.

α-Glucosidase inhibitors and phytotoxins from Streptomyces xanthophaeus.

Twenty-four metabolites 1-24 were isolated from the fermentation broth of Streptomyces xanthophaeus. Their structures were elucidated on the basis of spectroscopic analysis and by comparison of their NMR data with literature data reported. Daidzein (1), genistein (2) and gliricidin (3) inhibited α-glucosidase in vitro with IC values of 174.

Gabosines P and Q, new carbasugars from Streptomyces sp. and their α-glucosidase inhibitory activity.

Two new polyoxygenated cyclohexenone 'ketocarbasugars', named gabosines P and Q (1 and 2), were isolated from the culture of the actinomycete Streptomycetes strain no. 8, along with two known cyclic dipeptides. The structures and absolute configurations of the new metabolites were determined by spectroscopic data (1D- and 2D-NMR, HR-ESI-MS, and IR), chemical transformation, and electronic circular dichroism (ECD).

Oligotrophy is Helpful for the Isolation of Bioactive Actinomycetes.

It is necessary to develop new methods for the isolation of unknown actinomycetes from soils. To evaluate the effects of oligotrophic medium on the isolation of soil actinomycetes and develop a new isolation method, the Gause's synthetic medium was diluted to one tenth the recommended concentration in the present study. Soil dilution plate technique was used to isolate actinomycetes from the soil samples.

Paenibacillus quercus sp. nov., isolated from rhizosphere of Quercus aliena var. acuteserrata.

A Gram-positive, spore-forming, rod-shaped and motile bacterium, designated strain 1-25(T), was isolated from the rhizosphere of Quercus aliena var. acuteserrata in Taibai Mountain, Shaanxi Province, China. 16S rRNA gene sequence analysis showed that strain 1-25(T) belongs to the genus Paenibacillus.

[Effects of actinomycetes agent on ginseng growth and rhizosphere soil microflora].

Taking the ginseng in Xiao Xing' an Mountains of Northeast China as test object, this paper studied the effects of applying Streptomyces pactum (Act12) on ginseng growth and on the soil microflora in root zone and root surface. After treated with Act12, the yield and quality of ginseng' s medicinal part improved, the induced enzyme activities in leaves and the root activity increased, and the numbers and proportions of soil bacteria and actinomycetes increased significantly while those of soil fungi decreased. Compared with the control, the soil microflora in treatment Act12 changed.

[Microecological mechanisms of red-leaf disease occurrence in Salvia miltiorrhiza Bge].

A comparative study was made on the nutrient content in rhizosphere soil and the microflora in rhizosphere soil and on rhizoplane of healthy and red-leaf diseased Salvia miltiorrhiza plants, aimed to approach the microecological mechanisms of red-leaf disease occurrence in S. miltiorrhiza. The N, P, K, and Mn contents in the diseased plant leaves were significantly lower than those in the healthy plant leaves (P < 0.

[Identification of two Fusarium isolates and their crude toxin allelopathic effect on Cucumis melo seedlings].

Eight fungi isolates were obtained from Fusarium-infected Cucumis melo (melon) plants and their rhizosphere soils. Taking melon cultivar 'Xitian 1' as test material, the re-inoculation and seed germination experiments were conducted to investigate the pathogenicity and growth inhibition effect of these fungi isolates on melon. Through the determination of the induced enzyme activities, resistant substance contents, and cell membrane permeability of potted melon roots, the allelopathic effect of the crude toxins of two harmful fungi was studied, and according to the morphological characteristics and Internal Transcribed Spacer (ITS) sequencing, the two harmful fungi were identified.

Bioactive alkaloids produced by Pseudomonas brassicacearum subsp. Neoaurantiaca, an endophytic bacterium from Salvia miltiorrhiza.

Eleven compounds were isolated from the culture of an endophytic bacterium Pseudomonas brassicacearum subsp. Neoaurantiaca in Salvia miltiorrhiza Bunge. Their structures were elucidated by spectroscopic methods as cyclo-(Gly-L-Ala) (1), cyclo-(L-Ala-L-Ala) (2), cyclo-(L-Pro-Gly) (3), cyclo-(L-Pro-L-Ser) (4), cyclo-(L-Ala-trans-4-hydroxy-L-Pro) (5), cyclo-(L-Val-L-Pro) (6), cyclo-(Gly-L-Tyr) (7), cyclo-(L-Ala-L-Tyr) (8), cyclo-(L-Tyr-trans-4-hydroxy-L-Pro) (9), 3-methylhydantoin (10) and 2-piperidinone (11).

[Distribution and characteristics of soil antagonistic actinomycetes on northern slope of Taibai Mountain, Qinling].

Twelve representative soil samples were collected from different altitudes on the northern slope of Taibai Mountain to study the distribution and characteristics of soil antagonistic actinomyces by using agar block method. There existed a great deal of soil antagonistic actinomyces in the study area. Among the 141 actinomycete strains isolated, 116 strains (82.

Enteractinococcus coprophilus gen. nov., sp. nov., of the family Micrococcaceae, isolated from Panthera tigris amoyensis faeces, and transfer of Yaniella fodinae Dhanjal et al. 2011 to the genus Enteractinococcus as Enteractinococcus fodinae comb. nov.

A novel actinobacterium, designated strain YIM 100590(T), was isolated from Panthera tigris amoyensis faeces collected from Yunnan Wild Animal Park in Yunnan province, south-west China. Phylogenetic analysis based on 16S rRNA gene sequence data showed that strain YIM 100590(T) is a member of the family Micrococcaceae. Cells were coccoid to oval (0.

Rubellimicrobium roseum sp. nov., a Gram-negative bacterium isolated from the forest soil sample.

A novel pink-coloured, non-spore-forming, non-motile, Gram-negative bacterium, designated YIM 48858(T), is described by using a polyphasic approach. The strain can grow at pH 6.5-9 (optimum at pH 7) and 25-30 degrees C (optimum at 28 degrees C).

[Ecological distribution and antimicrobial effects of soil actinomycetes in artificial vegetation systems in Shazhuyu of Qinghai, China].

In order to probe into the effects of artificial vegetation rehabilitation on soil actinomycetes, dilution plate and agar block methods were used to investigate the ecological distribution and antimicrobial effects of actinomycetes in sandy soil in Shazhuyu area of Qinghai after artificial vegetation restoration. The results showed that with the vegetation rehabilitation and the improvement of vegetation coverage on alpine sandy dry land, the quantity of soil actinomycetes increased significantly, being 145.4% higher in the grassland transferred from farmland than in sandy land.

[Effects of microwave irradiation on isolation of soil actinomycetes].

Dilution plate- and agar block methods were employed to study the effects of microwave irradiation on the isolation of soil actinomycetes. The results showed that: 1) Microwave irradiation could significantly increase the total quantity of isolated actinomycetes. With the increasing duration of microwave irradiation, the total quantity of actinomycetes in soils with high organic matter content tended to increase first and decrease then.

[Nutrient contents and microbial populations of aeolian sandy soil in Sanjiangyuan region of Qinghai Province].

Sanjiangyuan region (the headstream of three rivers) in Qinghai Province of China is the highest and largest inland alpine wetland in the world. The study on the nutrient contents and microbial populations of aeolian sandy soils in this region showed that soil organic matter content increased with the evolution of aeolian sand dunes from un-stabilized to stabilized state, being 5.9 and 3.