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In the present paper a review of the genus Macrocheilus HOPE, 1838 (Coleoptera: Carabidae: Helluonini) of China is provided, with descriptions of seven new species, viz. M. parvimaculatus sp. nov., M. gigas sp. nov., M. fuscipennis sp. nov., M. solidipalpis sp. nov., M. cheni sp. nov., M. quadratus sp. nov., and M. sinuatilabris sp. nov.. A key to all species found in China is also given. In addition, M. asteriscus White is reported from Laos, Indonesia and India for the first time.
Two efficient morphogenetic pathways for micropropagation of Bletilla striata (Thunb.) Reichb. f. have been established through the callus-mediated and direct formation of protocorm-like bodies (PLBs) from protocorms and shoot tips. Green calli were induced from the basal surface of protocorms and the cut-end of shoot tips on Vacin and Went (VW) medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) or α-naphthalene acetic acid (NAA) after 3–5 weeks, with the highest frequency of explants forming callus (48.0 %) from protocorms at 1.0 mg l⁻¹ 2,4-D. The calli obtained from all plant growth regulator (PGR) treatments could proliferate and differentiate PLBs on the PGR-free medium. NAA and 2,4-D significantly enhanced the growth of callus. The fastest growth rate of callus was achieved at the combination of 1.0 mg l⁻¹ 2,4-D and 1.0 mg l⁻¹ TDZ with 46.2- fold within 3 months. The regeneration of PLBs from callus was significantly improved by 6-benzyladenine (BA), and a mean number of 48.4 PLBs was produced from 100 mg calli at 1.0 mg l⁻¹ BA within 3 months. BA and thidiazuron (TDZ) promoted the direct formation of PLBs from explants. The highest frequency of direct PLBs formation (76.0 %) and the highest mean number of PLBs per explant (30.2) were observed in protocorms cultured with 0.5 mg l⁻¹ BA. Assessment of clonal fidelity by intersimple sequence repeat (ISSR) markers revealed similarity ranges of 99.8–100.0 % between the regenerants and their mother plants and 99.5–100.0 % among the regenerants, which suggested the micropropagation protocols were genetically stable.
Ecological security is the comprehensive characterization of the noosystem’s overall collaborative capacity in relation to human welfare within a whole society. Recent years, however, have witnessed the excessive exploitation of natural resources via anthropogenic activities that have consistently triggered or accelerated ecological deterioration. In addition, an adequate ecological security assessment has yet to be conducted in a steppe ecoregion, especially when considering that the steppe is the major ecoregion category in China. In this study, we selected a typical steppe ecoregion in Inner Mongolia, northern China, as a representative region to conduct a spatiotemporal assessment of ecological security from both global and local perspectives. Along with an evaluation indicator system constituting 25 separate indicators covering three different systems (society, economy, and nature), we applied an improved grey target decision-making method in the initial indicator conversion process. As it pertains to weight determination, we employed a weight calculation method that weighed all indicators synthetically. Research findings indicated that a progressive deterioration of ecological security has been observed in the typical steppe ecoregion of China from 1990 to 2014, with a decline in the security situation and even more severe deterioration observed from a local perspective than a global perspective. Social and economic systems, specifically an excessive rural population and unreasonable development (mainly grazing and mining), were the major factors that promoted ecological security deterioration, while the natural system has contributed only slightly to this deterioration.
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