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Legume, with a strong resistance to the adverse environmental conditions, is one of pioneer plants in the desert region and plays an important role in the protection of the ecological environment. In this study, the symbiosis of rhizobia associating with shrubby and herbaceous legumes in Shenmu area, Shaanxi, China was characterized by the 16S rRNA PCR-RFLP and sequence analysis of involved genes. A total of 55 strains were isolated and purified, including 30 strains from the shrubby legume Amorpha fruticosa and Caragana microphylla, and 25 strains from herbaceous plants Astragalus adsurgens, Medicago sativa and Astragalus melilotoides. Results showed that there were 11 16S rRNA genotypes. The strains isolated from herbaceous legumes belonged to five genus including Mesorhizobium, Ensifer, Rhizobium, Phyllobacterium and Agrobacterium, which were very close related to M. huakuii, M. mediterraneum, M. robiniae, E. fredii, E. meliloti, R. indigoferae, R. radiobacter, P. ifriqiyense and Ag. tumefaciens through the phylogenetic analysis. The strains isolated from shrubby legumes belonged to Mesorhizobium, and they were very close related to M. huakuii and M. mediterraneum which were shared simultaneously by shrubby and herbaceous legumes. All of these indicated the choice of rhizobia by the two types of legumes in the arid area was different, and it might depend on the species of host plant and environmental factors. [ABSTRACT FROM AUTHOR]

Abstract: Four ergosterol derivatives (1–4) have been isolated for the first time from the fruiting bodies of a basidiomycete fungus, Lactarius hatsudake, through activity-guided fractionation. Their structures were determined, using spectroscopic analysis, as: (22E,24R)-ergosta-5,7,22-dien-3β-ol (ergosterol, 1); 5α,8α-epidioxy-(22E,24R)-ergosta-6,22-dien-3β-ol (ergosterol peroxide, 2); 5α,8α-epidioxy-(24S)-ergosta-6-en-3β-ol (3); and (22E,24R)-ergosta-7,22-dien-3β,5α,6β-triol (cerevisterol, 4). Compounds 2 and 3 showed selective inhibitory activity against Crotalus adamenteus venom phospholipase A2 (PLA2) enzyme, but not against Apis mellifcra bee venom PLA2. The antiphospholipase A2 activity of compounds 2 and 3 are reported here for the first time. [Copyright &y& Elsevier]

Background and aims: NaHS, a donor of hydrogen sulfide (H2S), which is emerging as a potential signaling molecule, may regulate various physiological processes in plants. However, how soybean (Glycine max L.) responds to NaHS and rhizobia (Sinorhizobium fredii) inoculation remains unclear. Methods: We explored the effects of NaHS and rhizobia on the growth rate, nodules, nitrogenase activities (NA), chlorophyll content, soluble protein content, photosynthesis (Pn), chlorophyll fluorescent parameters, endogenous H2S accumulation, l/d‐cysteine desulfhydrase (GmLCD and GmDCD) gene expression, nitrogen (N), phosphorus (P), potassium (K) contents, and nutrient resorption. Results: The results showed that rhizobia significantly increased the shoot, root, total dry weight, and growth rate, and NaHS promoted nodule numbers and NA in soybean. Moreover, chlorophyll content, soluble protein content, Pn, endogenous H2S accumulation, and GmLCD and GmDCD gene expression levels were promoted by NaHS and rhizobia. In addition, during all growth stages of soybean, the levels of N, P, and K and the N:P ratio in different tissues were affected by NaHS and rhizobia. Additionally, NaHS and rhizobia also significantly enhanced N resorption efficiency (NRE) and K resorption efficiency (KRE), but decreased P resorption efficiency (PRE). Conclusion: Therefore, NaHS and rhizobia regulated the growth rate, nutrient stoichiometry, and nutrient resorption efficiency of soybean. These findings provide information that will be useful for predicting how NaHS and rhizobia lead to variations in nutrient uptake and nutrient conservation strategies. [ABSTRACT FROM AUTHOR]

This study was conducted to explore the fertilization potential of the high-volume straw returning mode in cooperation with Bacillus and other functional flora on desertification soil and to analyze the changing characteristics of soil carbon, nitrogen, and phosphorus components and functional activities of flora, so as to provide a basis for efficiently improving desertification soil fertility. A randomized block experiment was conducted, setting straw not returning to field (CK) and high-volume straw returning of 6.00 kg·m -2 (ST1), 12.00 kg·m -2 (ST2), 24.00 kg·m -2 +(ST3), 6.00 kg·m -2 + Bacillus (SM1), 12.00 kg·m -2 + Bacillus (SM2), and 24.00 kg·m -2 + Bacillus (SM3). In this study, we conducted a randomized block experiment to investigate the effect of the treatment for soil microbial and nutrient contents using 16S rRNA high-throughput sequencing and soil biochemical properties analysis. Our results showed that:① the α diversity of the soil bacterial community was significantly reduced by the combination of high-volume straw returning and Bacillus application. ② The single mode of high-volume straw returning significantly enriched Proteobacteria and decreased the relative abundance of Actinobacteriota, and the effect of the combined application of Bacillus on the variability of bacterial community structure was more significant. At the genus level, the relative abundance of beneficial bacteria such as Pseudomonas, Rhodanobacter, and Bacillus increased significantly. ③ The functional prediction based on FAPROTAX found that the high-volume straw returning combined with Bacillus could significantly improve the decomposition potential of soil flora to organic substances and the transformation potential of nitrogen components. ④ Compared with that in the control, the application of Bacillus with high-volume straw returning significantly increased the contents of soil organic matter, total phosphorus, and available phosphorus by 31.20-32.75 g·kg -1 , 0.11-0.18 g·kg -1 , and 29.69-35.09 mg·kg -1 , respectively. In conclusion, the application of Bacillus in the sand-blown area with a high-volume straw returning can notably improve the contents of soil organic matter and phosphorus components, the functional activity of bacteria, and the abundance of beneficial bacteria, which is of great significance to the rapid improvement of soil fertility in the middle- and low-yield fields in arid areas.

Hydrogen sulfide (H 2 S) performs a crucial role in plant development and abiotic stress responses by interacting with other signalling molecules. However, the synergistic involvement of H 2 S and rhizobia in photosynthetic carbon (C) metabolism in soybean (Glycine max) under nitrogen (N) deficiency has been largely overlooked. Therefore, we scrutinised how H 2 S drives photosynthetic C fixation, utilisation, and accumulation in soybean-rhizobia symbiotic systems. When soybeans encountered N deficiency, organ growth, grain output, and nodule N-fixation performance were considerably improved owing to H 2 S and rhizobia. Furthermore, H 2 S collaborated with rhizobia to actively govern assimilation product generation and transport, modulating C allocation, utilisation, and accumulation. Additionally, H 2 S and rhizobia profoundly affected critical enzyme activities and coding gene expressions implicated in C fixation, transport, and metabolism. Furthermore, we observed substantial effects of H 2 S and rhizobia on primary metabolism and C-N coupled metabolic networks in essential organs via C metabolic regulation. Consequently, H 2 S synergy with rhizobia inspired complex primary metabolism and C-N coupled metabolic pathways by directing the expression of key enzymes and related coding genes involved in C metabolism, stimulating effective C fixation, transport, and distribution, and ultimately improving N fixation, growth, and grain yield in soybeans., (© 2023 John Wiley & Sons Ltd.)

Legume, with a strong resistance to the adverse environmental conditions, is one of pioneer plants in the desert region and plays an important role in the protection of the ecological environment. In this study, the symbiosis of rhizobia associating with shrubby and herbaceous legumes in Shenmu area, Shaanxi, China was characterized by the 16S rRNA PCR-RFLP and sequence analysis of involved genes. A total of 55 strains were isolated and purified, including 30 strains from the shrubby legume Amorpha fruticosa and Caragana microphylla, and 25 strains from herbaceous plants Astragalus adsurgens, Medicago sativa and Astragalus melilotoides. Results showed that there were 11 16S rRNA genotypes. The strains isolated from herbaceous legumes belonged to five genus including Mesorhizobium, Ensifer, Rhizobium, Phyllobacterium and Agrobacterium, which were very close related to M. huakuii, M. mediterraneum, M. robiniae, E. fredii, E. meliloti, R. indigoferae, R. radiobacter, P. ifriqiyense and Ag. tumefaciens through the phylogenetic analysis. The strains isolated from shrubby legumes belonged to Mesorhizobium, and they were very close related to M. huakuii and M. mediterraneum which were shared simultaneously by shrubby and herbaceous legumes. All of these indicated the choice of rhizobia by the two types of legumes in the arid area was different, and it might depend on the species of host plant and environmental factors.

In the title compound, C(12)H(15)ClO(3), the eth-oxy group is nearly coplanar with the benzene ring, making a dihedral angle of 9.03 (4)°, and is involved in an intra-molecular O-H⋯O hydrogen bond to the neighbouring hy-droxy group.

In the title compound, C(10)H(11)ClO(3), obtained by the reaction of 2,4-dihy-droxy-acetophenone, potassium carbonate and 1-bromo-2-chloro-ethane, an intra-molecular O-H⋯O hydrogen bond occurs.

The taxonomic position of an actinomycete isolated from a lead-polluted soil in Gansu province, north-west China, was determined by using a polyphasic approach. Chemical and morphological properties of the isolate, designated strain CCNWHX 13-160(T), were similar to those of streptomycetes. Analysis of the almost complete 16S rRNA gene sequence placed strain CCNWHX 13-160(T) in the genus Streptomyces where it formed a distinct phyletic line with recognized Streptomyces species. The strain was most similar to Streptomyces pseudovenezuelae NBRC 12904(T) (98.9 %) and Streptomyces resistomycificus NBRC 12814(T) (98.8 %). Furthermore, DNA-DNA hybridization studies between the novel isolate and these two strains showed relatedness values of 49.7+/-0.8 and 43.2+/-1.1 %, respectively. It is proposed that strain CCNWHX 13-160(T) (=ACCC 41207(T)=HAMBI 2991(T)) be classified as the type strain of a novel species in the genus Streptomyces, Streptomyces plumbiresistens sp. nov. The MIC of Pb(2+) for growth of strain CCNWHX 13-160(T) was 4.0 mM.