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51.
52.
Sufang Zhang Sifan Shen Jiong Peng Xin Zhou Xiangbo Kong Pingping Ren Fu Liu Lingling Han Shuai Zhan Yongping Huang Aibing Zhang Zhen Zhang 《Molecular ecology resources》2020,20(4):1023-1037
Dendrolimus spp. are important destructive pests of conifer forests, and Dendrolimus punctatus Walker (Lepidoptera; Lasiocampidae) is the most widely distributed Dendrolimus species. During periodic outbreaks, this species is said to make “fire without smoke” because large areas of pine forest can be quickly and heavily damaged. Yet, little is known about the molecular mechanisms that underlie the unique ecological characteristics of this forest insect. Here, we combined Pacific Biosciences (PacBio) RSII single‐molecule long reads and high‐throughput chromosome conformation capture (Hi‐C) genomics‐linked reads to produce a high‐quality, chromosome‐level reference genome for D. punctatus. The final assembly was 614 Mb with contig and scaffold N50 values of 1.39 and 22.15 Mb, respectively, and 96.96% of the contigs anchored onto 30 chromosomes. Based on the prediction, this genome contained 17,593 protein‐coding genes and 56.16% repetitive sequences. Phylogenetic analyses indicated that D. punctatus diverged from the common ancestor of Hyphantria cunea, Spodoptera litura and Thaumetopoea pityocampa ~ 108.91 million years ago. Many gene families that were expanded in the D. punctatus genome were significantly enriched for the xenobiotic biodegradation system, especially the cytochrome P450 gene family. This high‐quality, chromosome‐level reference genome will be a valuable resource for understanding mechanisms of D. punctatus outbreak and host resistance adaption. Because this is the first Lasiocampidae insect genome to be sequenced, it also will serve as a reference for further comparative genomics. 相似文献
53.
Jing-Ming Yang Ya-Yue Liu Wen-Cong Yang Xiao-Xiang Ma Ying-Ying Nie Evgenia Glukhov 《Bioscience, biotechnology, and biochemistry》2020,84(8):1546-1553
ABSTRACT A new isoflavone derivative compound 1 (psoralenone) was isolated from soybean inoculated with a marine fungus Aspergillus terreus C23-3, together with seven known compounds including isoflavones 2–6, butyrolactone I (7) and blumenol A (8). Their structures were elucidated by MS, NMR, and ECD. Psoralenone displayed moderate in vitro anti-inflammatory activity in the LPS-induced RAW264.7 cell model. Compound 2 (genistein) showed moderate acetylcholinesterase (AChE) inhibitory activity whereas compounds 2, 5 (biochanin A), 6 (psoralenol), and 7 exhibited potent larvicidal activity against brine shrimp. Compounds 3 (daidzein), 4 (4?-hydroxy-6,7-dimethoxyisoflavone), and 5–7 showed broad-spectrum anti-microbial activity, and compound 7 also showed moderate 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity. 相似文献
54.
亚硝酸盐是氮循环过程的中间产物,其积累超过一定量则会抑制微生物的生长与代谢,也会给人与水生生物带来健康风险。而在高氮污水生物脱氮工艺中,持续维持亚硝酸盐的积累能实现短程硝化过程,降低生物脱氮的能耗进而降低运营成本。本文综述了在水环境中亚硝酸盐积累的生物过程与积累原因,并对影响亚硝酸盐积累的因素进行了总结,旨在为提高污水处理过程中氮的去除效率,降低运营成本,减少排放污水及自然水体中亚硝态氮含量提供参考。 相似文献
55.
植被综合生态质量时空变化动态监测评价模型 总被引:6,自引:3,他引:3
为了能掌握全国植被综合生态质量的高低及其时空变化,构建了既能反映植被生产力又能反映植被覆盖度的植被综合生态质量指数,建立了植被综合生态质量指数年际对比和多年变化趋势评价模型。利用构建的指数和评价模型,以2017年作为监测评价的当年,以2000—2017年作为评价的多年时段,对全国植被综合生态质量时空变化进行了监测评价。结果表明:(1)2017年全国大部地区植被综合生态质量指数高于2000—2016年多年平均值,生态质量偏好;2017年福建、广西、海南、广东、云南植被综合生态质量位居全国前五位,构建的植被综合生态质量指数及其年际对比模型可以定量反映全国植被综合生态质量的空间差异和年际差异。(2)全国有90.7%的区域2000—2017年植被综合生态质量指数呈提高趋势,东北地区西部、内蒙古东部、华北大部、西北地区东部、西南地区东部、华南西部等地生态质量指数提升明显,构建的植被综合生态质量指数多年变化趋势评价模型可以定量反映植被生态质量的多年变化趋势和幅度。(3)南方大部地区2000—2017年平均年植被综合生态质量指数在50.0以上,北方大部地区在50.0以下;我国中东部大部地区在20.0以上,西部大部地区在20.0以下,表明南方大部地区年植被生态质量好于北方、中东大部好于西部。可见,构建的植被综合生态质量指数及其年际对比和多年变化趋势评价模型,能够监测评价当年和多年全国植被综合生态质量的时空变化,可为掌握全国植被生态质量动态提供模型和方法。 相似文献
56.
Yuanming Xiao Lucun Yang Xiuqing Nie Changbin Li Feng Xiong Lingling Wang Guoying Zhou 《Ecology and evolution》2020,10(13):6723-6731
Periodic climatic oscillations and species dispersal during the postglacial period are two important causes of plant assemblage and distribution on the Qinghai‐Tibet Plateau (QTP). To improve our understanding of the bio‐geological histories of shrub communities on the QTP, we tested two hypotheses. First, the intensity of climatic oscillations played a filtering role during community structuring. Second, species dispersal during the postglacial period contributed to the recovery of species and phylogenetic diversity and the emergence of phylogenetic overdispersion. To test these hypotheses, we investigated and compared the shrub communities in the alpine and desert habitats of the northeastern QTP. Notably, we observed higher levels of species and phylogenetic diversity in the alpine habitat than in the desert habitat, leading to phylogenetic overdispersion in the alpine shrub communities versus phylogenetic clustering in the desert shrub communities. This phylogenetic overdispersion increased with greater climate anomalies. These results suggest that (a) although climate anomalies strongly affect shrub communities, these phenomena do not act as a filter for shrub community structuring, and (b) species dispersal increases phylogenetic diversity and overdispersion in a community. Moreover, our investigation of the phylogenetic community composition revealed a larger number of plant clades in the alpine shrub communities than in the desert shrub communities, which provided insights into plant clade‐level differences in the phylogenetic structures of alpine and desert shrub communities in the northeastern QTP. 相似文献
57.
Photosynthesis Research - Formation of photosynthetic complexes leads to a higher demand for Fe–S clusters. We hypothesized that in the facultative phototrophic alpha-proteobacterium... 相似文献
58.
Chen Minmin Nie Gongping Yang Liuyan Zhang Yongchun Cai Youming 《Plant Growth Regulation》2021,95(1):49-64
Plant Growth Regulation - As one of the most popular bulbous plant with high ornamental value, Lilium spp. has been used as cut flower or green plants in urban landscapes and home gardening. We... 相似文献
59.
Wang Fubiao Sun Huimin Rong Lingling Li Zhaowei An Ting Hu Wenhai Ye Zipiao 《Plant Growth Regulation》2021,95(1):121-136
Plant Growth Regulation - To clarify the genotypic-dependent alternation in D1 protein turnover and PSII repair cycle and its relation to light intensity in senescent leaves of rice, two rice... 相似文献