Background Ferula sinkiangensis is an increasingly endangered medicinal plant. Arbuscular mycorrhiza fungi (AMF) are symbiotic microorganisms that live in the soil wherein they enhance nutrient uptake, stress resistance, and pathogen defense in host plants. While such AMF have the potential to contribute to the cultivation of Ferula sinkiangensis, the composition of AMF communities associated with Ferula sinkiangensis and the relationship between these fungi and other pertinent abiotic factors still remains to be clarified. Results Herein, we collected rhizosphere and surrounding soil samples at a range of depths (0–20, 20–40, and 40–60 cm) and a range of slope positions (bottom, middle, top). These samples were then subjected to analyses of soil physicochemical properties and high-throughput sequencing (Illumina MiSeq). We determined that Glomus and Diversispora species were highly enriched in all samples. We further found that AMF diversity and richness varied significantly as a function of slope position, with this variation primarily being tied to differences in relative Glomus and Diversispora abundance. In contrast, no significant relationship was observed between soil depth and overall AMF composition, although some AMF species were found to be sensitive to soil depth. Many factors significantly affected AMF community composition, including organic matter content, total nitrogen, total potassium, ammonium nitrogen, nitrate nitrogen, available potassium, total dissolvable salt levels, pH, soil water content, and slope position. We further determined that Shannon diversity index values in these communities were positively correlated with total phosphorus, nitrate-nitrogen levels, and pH values (P < 0.05), whereas total phosphorus, total dissolvable salt levels, and pH were positively correlated with Chao1 values (P < 0.05). Conclusion In summary, our data revealed that Glomus and Diversispora are key AMF genera found within Ferula sinkiangensis rhizosphere soil. These fungi are closely associated with specific environmental and soil physicochemical properties, and these soil sample properties also differed significantly as a function of slope position (P < 0.05). Together, our results provide new insights regarding the relationship between AMF species and Ferula sinkiangensis, offering a theoretical basis for further studies of their development.

Snow lotus (Saussurea involucrata (Kar. & Kir.) Sch. Bip.) is an economically important medicinal herb increasingly grown in China in recent years. During the summer and autumn of 2005, 2006, and 2007, a necrosis of unknown etiology was observed on leaves in commercial production areas in Xinjiang Province of China. Disease incidence was approximately 40 to 50% of the plants during the 2005 and 2007 growing seasons. Initial symptoms consisted of pronounced water-soaked, dark brown-to-black spots that were 1 to 2 mm in diameter on young, expanding leaves. Later, some leaf spots on older leaves enlarged and coalesced, causing leaf desiccation. Leaf samples were collected in 2005, 2006, and 2007 from the affected hosts. Bacterial streaming was evident from these samples, and 28 strains were isolated on nutrient agar or King's medium B (KMB). All strains were gram negative and fluoresced bluegreen under UV light after 48 h of growth at 28°C on KMB. On the basis of LOPAT tests, the strains were identified as Pseudomonas syringae (1). The identity of two strains was confirmed by sequencing the 16S rDNA gene, which revealed 98% similarity to P. syringae strains in NCBI (Accession Nos. FJ001817 and FJ001818 for XJSNL 111 and 107, respectively). Infiltration of tobacco leaves with bacterial suspensions resulted in typical hypersensitivity reactions within 24 h. Pathogenicity of the strains was confirmed by spray inoculating five snow lotus leaves of a six-leaf stage plant with 108 CFU ml–1 bacterial suspensions in sterile water and five plants sprayed with sterile distilled water served as controls. Inoculated and sterile water-sprayed controls were maintained in the growth chamber with 90% relative humidity for 15 days at 15 ± 2°C. Symptoms similar to the original symptoms were observed on inoculated plants after 2 weeks. No symptoms developed on controls. Bacteria reisolated from inoculated plants were identified as strains of P. syringae. Isolates were deposited at the Key Laboratory for Oasis Crop Disease Prevention and Cure, Shihezi University. Rust caused by Puccinia carthami and leaf spot disease caused by Alternaria carthami of snow lotus have been reported (2,3). To our knowledge, this is the first report of P. syringae as the cause of bacterial leaf spot on snow lotus in China. References: (1) A. Braun-Kiewnick and D. C. Sands. Pseudomonas. Page 84 in: Laboratory Guide for the Identification of Plant Pathogenic Bacteria. 3rd ed. N. W. Schaad et al., eds. The American Phytopathological Society, St. Paul, MN, 2001. (2) S. Zhao et al. Plant Dis. 91:772, 2007. (3) S. Zhao et al. Plant Dis. 92:318, 2008.

Background: Ferula sinkiangensis is an increasingly endangered medicinal plant. Arbuscular mycorrhiza fungi (AMF) are symbiotic microorganisms that live in the soil wherein they enhance nutrient uptake, stress resistance, and pathogen defense in host plants. While such AMF have the potential to aid in Ferula sinkiangensis cultivation, the composition of AMF communities associated with Ferula sinkiangensis and the relationship between these fungi and other pertinent abiotic factors remain to be clarified.Results: Herein, we collected samples of rhizosphere and surrounding soil at a range of depths (0-20, 20-40, and 40-60 cm) and a range of slope positions (bottom, middle, top). These samples were then subjected to analyses of soil physicochemical properties and high-throughput sequencing (Illumina MiSeq). We determined that Glomus and Diversispora species were highly enriched in all samples. We further found that AMF diversity and richness varied significantly as a function of slope position, with this variation primarily being tied to differences in relative Glomus and Diversispora abundance. In contrast, no significant relationship was observed between soil depth and overall AMF composition, although some AMF species were found to be sensitive to soil depth. Many factors were found to significantly affect AMF community composition, including organic matter content, total nitrogen, total potassium, ammonium nitrogen, nitrate nitrogen, available potassium, total dissolvable salt levels, pH, soil water content, and slope position. We further found that Shannon diversity index values in these communities were positively correlated with total phosphorus, nitrate-nitrogen levels, and pH values (P<0.05), whereas total phosphorus, total dissolvable salt levels, and pH were positively correlated with Chao1 values (P<0.05).Conclusion: In summary, these findings reveal that Glomus and Diversispora are key AMF genera found within the rhizosphere soil of Ferula sinkiangensis. These fungi are closely associated with specific environmental and soil physicochemical properties. The physical and chemical properties of these soil samples also differed significantly as a function of slope position (P<0.05). Together, our results provide new insights regarding the relationship between AMF species and Ferula sinkiangensis, providing a theoretical basis for further studies of their development.

Background: Ferula sinkiangensis is an increasingly endangered medicinal plant. Arbuscular mycorrhiza fungi (AMF) are symbiotic microorganisms that live in the soil wherein they enhance nutrient uptake, stress resistance, and pathogen defense in host plants. While such AMF have the potential to contribute to the cultivation of Ferula sinkiangensis, the composition of AMF communities associated with Ferula sinkiangensis and the relationship between these fungi and other pertinent abiotic factors still remains to be clarified.Results: Herein, we collected rhizosphere and surrounding soil samples at a range of depths (0-20, 20-40, and 40-60 cm) and a range of slope positions (bottom, middle, top). These samples were then subjected to analyses of soil physicochemical properties and high-throughput sequencing (Illumina MiSeq). We determined that Glomus and Diversispora species were highly enriched in all samples. We further found that AMF diversity and richness varied significantly as a function of slope position, with this variation primarily being tied to differences in relative Glomus and Diversispora abundance. In contrast, no significant relationship was observed between soil depth and overall AMF composition, although some AMF species were found to be sensitive to soil depth. Many factors significantly affected AMF community composition, including organic matter content, total nitrogen, total potassium, ammonium nitrogen, nitrate nitrogen, available potassium, total dissolvable salt levels, pH, soil water content, and slope position. We further determined that Shannon diversity index values in these communities were positively correlated with total phosphorus, nitrate-nitrogen levels, and pH values (P<0.05), whereas total phosphorus, total dissolvable salt levels, and pH were positively correlated with Chao1 values (P<0.05). Conclusion: In summary, our data revealed that Glomus and Diversispora are key AMF genera found within Ferula sinkiangensis rhizosphere soil. These fungi are closely associated with specific environmental and soil physicochemical properties, and these soil sample properties also differed significantly as a function of slope position (P<0.05). Together, our results provide new insights regarding the relationship between AMF species and Ferula sinkiangensis, offering a theoretical basis for further studies of their development.

Background: Ferula sinkiangensis is an important and increasingly endangered medicinal plant. Arbuscular mycorrhiza fungi (AMF) are microbes that live in the soil and can enhance nutrient uptake, stress resistance, and pathogen defens in host plants. The composition of AMF communities associated with Ferula sinkiangensis and the relationship between these fungi and other pertinent abiotic factors, however, remains uncertain. Herein, we collected samples of rhizosphere and surrounding soil at a range of depths (0-20, 20-40, and 40-60 cm) and a range of slop positions (bottom, middle, top). These samples were then subjected to analyses of soil physicochemical properties and high-throughput sequencing (Illumina MiSeq), enabling us to examine AMF community composition and diversity, as well as the relationship between these parameters and other abiotic factors. Results: Through this analysis, we determined that Glomus and Diversispora were enriched in all samples. AMF diversity and richness varied significantly as a function of slope position, with this variation primarily being tied to differences in Glomus and Diversispora abundance. In contrast, no significant relationship between soil depth and overall AMF composition was noted, although some AMF were found to be sensitive to depth. Many factors were found to significantly affect AMF community composition, including organic matter (OM), TN (total nitrogen), TK (total potassium), AN (ammonium nitrogen), NN (nitrate nitrogen), AK (available potassium), TDS (total soluble salt), pH, SM (soil water content), and AE (slope position). We further found that Shannon diversity index values in these communities were positively correlated with TP (total phosphorus), NN, and pH values (p<0.05), while TP, TDS, and pH were positively correlated with Chao1 values (p<0.05). Conclusion: In summary, these findings reveal that Glomus and Diversispora are key AMF genera found within the rhizosphere soil of Ferula sinkiangensis. These fungi are closely associated with specific environmental and soil physicochemical properties. And The physical and chemical properties of soil were significantly different (p<0.05) because of slope position. Together, our results provide a novel understanding of the relationship between AMF species and Ferula sinkiangensis, providing a theoretical basis for further studies of their development.