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Plant growth regulators are a class of physiologically active substances that could modify or regulate basic physiological processes in the plant and defense against abiotic and biotic stresses, including natural plant growth regulators and synthetic ones. Different from natural plant growth regulators with low content and high cost of extraction in plants, synthetic ones can be produced in large‐scale production and widely used in agriculture for increasing and securing yield and quality of the harvested produce. However, like pesticides, the abuse of plant growth regulators will have negative impacts on human beings. Therefore, it is important to monitor plant growth regulators residues. Due to the low concentration of plant growth regulators and complex matrices of food, it is necessary to isolate and extract plant growth regulators by appropriate adsorbents in sample preparation for obtaining satisfactory results. In the last decade, several advanced materials as adsorbents have shown superiority in sample preparation. This review briefly introduces the recent application and progress of advanced materials as adsorbents in sample preparation for extraction of plant growth regulators from the complex matrix. In the end, the challenge and outlook about the extraction of plant growth regulators of these advanced adsorbents in sample preparation are presented. [ABSTRACT FROM AUTHOR]

The effect of altitude on the composition and diversity of microbial communities have attracted highly attention recently but is still poorly understood. We used 16S rRNA gene clone library analyses to characterize the bacterial communities from the rhizosphere and roots of Stellera chamaejasme in the Tibetan Plateau. Our results revealed that Actinobacteria and Proteobacteria were dominant bacteria in this medicinal plant in the rhizosphere and root communities. The Shannon diversity index showed that the bacterial diversity of rhizosphere follows a small saddle pattern, while the roots possesses of a hump-backed trend. Significant differences in the composition of bacterial communities between rhizosphere and roots were detected based on multiple comparisons analysis. The community of Actinobacteria was found to be significantly negative correlated with soil available P (p < 0.01), while the phylum of Proteobacteria showed a positive relationship with available P (p < 0.05). Moreover, redundancy analysis indicated that soil phosphorus, pH, latitude, elevation and potassium positively correlated with bacterial communities associated with rhizosphere soils. Taken together, we provide evidence that bacterial communities associated with S. chamaejasme exhibited some certain elevational pattern, and bacterial communities of rhizosphere soil were regulated by environmental characteristics along elevational gradients in this alpine ecosystem. [ABSTRACT FROM AUTHOR]

A new cycloartane-type triterpenoid, 3β-acetoxy-9β,19-cyclolanost-24E-ene-1α,16β-diol-27-O-β-d-glucopyranoside (1), together with three known ones (2–4) were isolated from the aerial parts of Astragalus hoantchy. The structure of compound 1 was elucidated by detailed spectroscopic analyses including 1D and 2D NMR, HRESIMS, and IR experiments. All of the four compounds were isolated from A. hoantchy for the first time. The antifungal activities of compounds 1–4 against a phytopathogenic fungus (Alternaria solani) were evaluated with the result that compound 3 exhibited a moderate activity with an IC50 value of 284 μg/mL. [ABSTRACT FROM AUTHOR]

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