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Characterization of two chimeric sesterterpene synthases from a fungal symbiont isolated from a sesterterpenoid-producing Lamiaceae plant Leucosceptrum canum

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Chinese Chemical Letters 2023年第1期34卷 279-283页

作者： Desen Li Minjie Yang Rongfang Mu Shihong Luo yuegui chen Wenyuan Li An Wang Kai Guo Yan Liu Shenghong Li State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China State Key Laboratory of Southwestern Chinese Medicine Resources and Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengdu 611137China College of Bioscience and Biotechnology Shenyang Agricultural UniversityShenyang 110866China University of Chinese Academy of Sciences Beijing 100049China

Two chimeric sesterterpene synthases(Aa TPS1 and Aa TPS2)were functionally characterized from Alternaria alternata MB-30 isolated from the leaves of a sesterterpenoid-producing Lamiaceae plant Leucosceptrum *** TPS1 generated a 5/8/6/5 tetracyclic sesteraltererol(1)and its absolute stereochemistry was determined by X-ray crystallographic analysis of its derivative 10,11-epoxysesteraltererol(2),which enabled revision of the absolute configuration of C7 of sesterfisherol produced by Nf SS and PTTS014 characterized previously and its derivative 10,*** TPS2 produced a 5/15 bicyclic preterpestacin I(3).Site-directed mutagenesis suggested that F192 in Aa TPS1 was likely involved in controlling of the hydroxylation of C12,and eight amino acids were important for the enzyme activity of Aa TPS1 and Aa *** engineered Escherichia coli and Saccharomyces cerevisiae strains were constructed for the productions of compounds 1 and 3,and the highest titer of compound 1 reached 62.3 mg/L in shake-flask *** compounds 1 and 2 showed anti-adipogenic activity.

关键词： Sesterterpenoids Chimeric sesterterpene synthases Plant symbiotic fungi Alternaria alternata Leucosceptrum canum Anti-adipogenic activity

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Unraveling the serial glycosylation in the biosynthesis of steroidal saponins in the medicinal plant Paris polyphylla and their antifungal action

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Acta Pharmaceutica Sinica B 2023年第11期13卷 4638-4654页

作者： yuegui chen Qin Yan Yunheng Ji Xue Bai Desen Li Rongfang Mu Kai Guo Minjie Yang Yang Tao Jonathan Gershenzon Yan Liu Shenghong Li State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengdu 611137China Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Max Planck Institute for Chemical Ecology Jena D-07745Germany University of Chinese Academy of Sciences Beijing 100049China

Sugar-sugar glycosyltransferases play important roles in constructing complex and bioactive ***,we characterized a series of UDP-glycosyltransferases responsible for biosynthesizing the branched sugar chain of bioactive steroidal saponins from a widely known medicinal plant Paris polyphylla *** them,a 2'-O-rhamnosyltransferase and three 6'-O-glucosyltrasferases catalyzed a cascade of glycosylation to produce steroidal diglycosides and triglycosides,*** UDP-glycosyltransferases showed astonishing substrate promiscuity,resulting in the generation of a panel of 24 terpenoid glycosides including 15 previously undescribed compounds.A mutant library containing 44 variants was constructed based on the identification of critical residues by molecular docking simulations and protein model alignments,and a mutant UGT91AH1^(Y187A)with increased catalytic efficiency was *** steroidal saponins exhibited remarkable antifungal activity against four widespread strains of human pathogenic fungi attributed to ergosterol-dependent damage of fungal cell membranes,and 2'-O-rhamnosylation appeared to correlate with strong antifungal *** findings elucidated the biosynthetic machinery for their production of steroidal saponins and revealed their potential as new antifungal agents.

关键词： Paris polyphylla var.yunnanensis Steroidal saponins Glycosyltransferases Sugar chain elongation Antifungal activity

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Advances in Studies of Genetic Improvement of Sugarcane

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Asian Agricultural Research 2016年第11期8卷 66-70页

作者： Mingfu WEN Junxian YANG Fangyin PAN Wenlong WU yuegui chen Jinyan GUAN Guangzhou Sugarcane Industry Research Institute / Guangdong Key Lab of Sugarcane Improvement & Biorefinery

Sugarcane(Saccharum spp.) is a large perennial herbaceous plant that is cultivated in tropical and subtropical regions of the world,and it is also one of the most efficient crops in the world in converting energy from sunlight into chemical energy. As an essential sugar crop and energy crop,sugarcane is receiving an increasing concern for its variety improvement. Traditional breeding and cultivation techniques have contributed a lot to increasing sugarcane yield and sucrose content. In recent years,development and application of biotechnology provide much help for genetic improvement of sugarcane. For convenience of breeders fully knowing advances in studies of sugarcane genetic improvement,this paper elaborated conventional breeding,genomics,GM technology,and molecular marker assisted breeding.

关键词： Sugarcane Genetic improvement Genomics Transgene technology Molecular marker assisted breeding

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Effect of 30% Tiange Multifunctional Pesticide-Fertilizer on Sugarcane Pests and Yield

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Asian Agricultural Research 2017年第7期9卷 49-52页

作者： Jiangjiang XIE yuegui chen Dongyong PENG Chunqiang YANG Xuejun HUANG Guan WU Cong chen Junxian YANG Guangzhou Sugarcane Industry Research Institute/Guangdong Key Laboratory of Sugarcane Improvement and Biorefinery

In order to study the effect of 30% Tiange multifunctional pesticide-fertilizer on sugarcane pests and sugarcane yield,the field test was conducted with conventional compound fertilizer and 3% carbofuran fertilizer granules as control. The results showed that 30% Tiange multifunctional pesticide-fertilizer could effectively suppress some pests such as sugarcane borer,thrip,aphid and cockchafer. 90 d after pesticide-fertilizer application,the sugarcane withered heart rate was 1. 55% and 2. 55% in the two test points,respectively,significantly lower than the rate of 15. 40% and 19. 40% under control. Before harvest,the sugarcane borer damage rate in the two test points under pesticide-fertilizer treatment was 8. 70% and 9. 47%,respectively,significantly lower than the rate of 34. 50% and 33. 50% under control,and the sugarcane yield was 21. 16% and 22. 14% higher than under control,respectively. 30% Tiange multifunctional pesticide-fertilizer had nutritional and insecticidal effect,which could help to achieve sugarcane pesticide-fertilizer integration and save labor and costs.

关键词： 30% Tiange Pesticide-fertilizer integration Sugarcane pests Control effect Yield

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Application of AHP and DTOPSIS in Sugarcane Breeding

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Agricultural Biotechnology 2013年第5期2卷 9-12,16页

作者： Jiantao WU Junxian YANG Fuye LIU Qiwei LI Wenlong WU Fangyin PAN Jing XIE yuegui chen Guangzhou Sugarcane Industry Research Institute/Guangdong Key Lab of Sugarcane Improvement & Biorefinery

The weights of ten important traits of sugarcane, including the number of hair groups, plant height, defoliation capability, stalk diameter, ratooning property, stalk number of disease resistance, cane yield, sucrose content and sugar yield, were distributed with the Analytic Hierarchy Process （AHP） method. Ten Yuetang series of sugarcane lines were evaluated by Dynamic Technique for Order Preference by Similarity to Ideal Solution （DTOPSIS）. AHP results indicated that the weights of ten traits were 0. 013 4, 0.022 7, O. 030 2, 0.040 8, 0.065 3, 0.088 1, 0.116 2, 0. 160 6, 0.198 4 and 0.264 5, respectively, with random consistency ratio C.R. =0.098 1 〈0.1, suggesting that the distribution of the weights of evaluation indicators was reasonable. Comprehensive evaluation of 10 sugarcane lines by DTOPSLS method combining with the conclusion of AHP showed that the comprehensive performances of Yuetang 03-393 and Yuetang 03-373 were much better than other sugarcane lines, with relative approach degree Ci ranking the first and second, respectively, which was basically consistent with the practical survey, suggesting that Yuetang 03-393 and Yuetang 03-373 were suitable for large-scale popularization. The above results confirmed the feasibility of applying AHP and DTOPSIS in comprehensive evaluation of new crop varieties and provided reference for the breeding of new sugarcane lines.

关键词： AHP DTOPSIS Sugarcane Breeding Comprehensive evaluation

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指导学生进行有效的小学数学阅读

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基础教育研究 2020年第16期 54-55页

作者：陈月桂福鼎市实验小学福建福鼎355200

在数学教学中培养学生的阅读能力,可以保障学生把握数学知识的准确度,提高学生信息整合和信息分析的能力。文章从丰富阅读材料、把握阅读时机、指导阅读方法、培养阅读习惯四个方面,探讨如何在小学数学课堂教学中指导学生进行有效的数... 详细信息

在数学教学中培养学生的阅读能力,可以保障学生把握数学知识的准确度,提高学生信息整合和信息分析的能力。文章从丰富阅读材料、把握阅读时机、指导阅读方法、培养阅读习惯四个方面,探讨如何在小学数学课堂教学中指导学生进行有效的数学阅读。

关键词：课堂教学数学阅读有效策略

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基于均衡系数的甘肃省水资源空间均衡研究

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水利规划与设计 2024年第11期 53-58页

作者：陈粤桂齐广平甘肃农业大学水利水电工程学院甘肃兰州730070

为分析甘肃省水资源的空间分布情况及开发利用效果,采用空间均衡系数法、基尼系数法等方法计算甘肃省水资源空间均衡系数,研究发现,甘肃省水资源开发利用存在明显差距,整体开发程度高且潜力有限;水负载基尼系数持续上升,2020年达峰值0.... 详细信息

为分析甘肃省水资源的空间分布情况及开发利用效果,采用空间均衡系数法、基尼系数法等方法计算甘肃省水资源空间均衡系数,研究发现,甘肃省水资源开发利用存在明显差距,整体开发程度高且潜力有限;水负载基尼系数持续上升,2020年达峰值0.81,各市水资源利用情况差距悬殊。水土资源匹配度普遍较低,多年平均基尼系数为0.63,整体分布不均衡;多年平均水资源效益的基尼系数为0.37,各市的水资源效益较为均衡,且全省用水效益呈持续上升趋势。水资源空间均衡系数评价为中度失衡,主要受到水资源整体匮乏、地区间开发不均等因素影响。研究结果有助于为甘肃省未来的水资源规划与管理提供理论参考。

关键词：水资源负载系数水土资源匹配系数用水效益基尼系数空间均衡

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减氮配施秸秆生物炭对双季稻产量和硅、氮营养的影响

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应用生态学报 2023年第4期34卷 993-1001页

作者：宁川川陈悦桂柳瑞李彤欣陈海浪田纪辉蔡昆争华南农业大学资源环境学院广州510642 华南农业大学农业农村部华南热带农业环境重点实验室广州510642 华南农业大学广东省生态循环农业重点实验室广州510642

氮和硅都是水稻重要的营养元素,但实际生产中经常过量施加氮肥而忽视硅肥的补充。秸秆生物炭含有丰富的硅,可作为一种潜在的硅肥。本研究通过连续3年的田间定位试验,探究氮肥减量配施秸秆生物炭对水稻产量和硅、氮营养的影响。试验包括... 详细信息

氮和硅都是水稻重要的营养元素,但实际生产中经常过量施加氮肥而忽视硅肥的补充。秸秆生物炭含有丰富的硅,可作为一种潜在的硅肥。本研究通过连续3年的田间定位试验,探究氮肥减量配施秸秆生物炭对水稻产量和硅、氮营养的影响。试验包括5个处理:常规施氮(180 kg·hm^(-2),N_(100))、减氮20%(N_(80))、减氮20%配施15 t·hm^(-2)生物炭(N_(80)+BC)、减氮40%(N_(60))、减氮40%配施15 t·hm^(-2)生物炭(N_(60)+BC)。结果表明:与N_(100)相比,减氮20%对水稻的硅、氮累积没有影响;减氮40%导致水稻叶片氮吸收量下降,却显著增加其硅含量(增幅14.0%~18.8%);而减氮配施生物炭大幅增加了水稻叶片硅累积,硅含量增幅达38.0%~63.3%,硅吸收量增幅达32.3%~49.9%,但进一步减少了水稻叶片氮含量。Pearson相关分析表明,成熟期水稻叶片硅含量与氮含量呈显著负相关,而硅吸收量与氮吸收量之间无相关关系。与N_(100)相比,减氮或减氮配施生物炭对土壤铵态氮和硝态氮的影响不大,却在一定程度上提高了土壤pH,减氮配施生物炭显著增加了土壤有机质和有效硅含量,增幅分别达28.8%~41.9%和21.1%~26.9%,且两者呈极显著正相关。此外,与N_(100)相比,减氮40%会降低水稻产量和籽粒结实率,而减氮20%和减氮配施生物炭不会影响水稻产量及产量性状。综上,适量减氮并配施秸秆生物炭在减少氮肥投入的同时,可提升土壤肥力和硅素供应,在双季稻生产中有一定的应用前景。

关键词：氮肥减量秸秆生物炭水稻产量硅氮

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圆筒混料机的设计研究

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农机使用与维修 2016年第8期 1-3页

作者：陈月贵姜兴乾苏华礼安阳市翔升冶金机械有限公司河南安阳455000 三门峡市科学技术情报研究所河南三门峡472000 安阳工学院河南安阳455000

随着社会的进步和经济的发展,冶金工业也得到了蓬勃的发展,由于混料机在冶金工业中有着广泛的用途,进而社会对混料机的需求越来越大。通过对圆筒混料机的总体设计,解决了以往圆筒混料机容易撒料、设备寿命低、安装、调试不便等问题。该... 详细信息

随着社会的进步和经济的发展,冶金工业也得到了蓬勃的发展,由于混料机在冶金工业中有着广泛的用途,进而社会对混料机的需求越来越大。通过对圆筒混料机的总体设计,解决了以往圆筒混料机容易撒料、设备寿命低、安装、调试不便等问题。该圆筒混料机具有运转平稳、耐冲击、耐磨损、使用寿命长、安装维修调试方便,并且生产效率高、安全可靠等一系列优点。

关键词：圆筒混料机混料机混合设备安全生产

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千里香离体再生体系的建立

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广东农业科学 2022年第7期49卷 26-32页

作者：罗艺杨淦麟谭嘉娜陈月桂罗剑飘杨俊贤广东省科学院南繁种业研究所湛江研究中心广东湛江524300 崇左市江州区农业技术推广站广西崇左532200

【目的】千里香自然播种的繁殖方式无法满足大面积生产种植需求,通过建立高效的离体再生体系为千里香组培种苗工厂化繁育奠定基础。【方法】以千里香成熟种子为外植体材料,研究不同激素浓度与配比和不同有机物对千里香种子萌发、增殖培... 详细信息

【目的】千里香自然播种的繁殖方式无法满足大面积生产种植需求,通过建立高效的离体再生体系为千里香组培种苗工厂化繁育奠定基础。【方法】以千里香成熟种子为外植体材料,研究不同激素浓度与配比和不同有机物对千里香种子萌发、增殖培养、壮苗培养和生根培养阶段的影响,获得无菌组培苗,进行炼苗移栽。【结果】千里香种子经75%酒精与0.1%升汞预处理后,最适萌发培养基为MS+6-BA 0.5 mg/L,萌发率为62.5%;丛生芽继代增殖最适基本培养基为MS培养基;增殖培养最适培养基配方为MS+6-BA 0.50 mg/L+NAA 0.15 mg/L,增殖系数达2.37;壮苗培养适宜培养基配方为MS+马铃薯汁30 g/L,40 d株高增长2.0 cm;生根培养最适培养基配方为1/2MS+IBA 0.6 mg/L+马铃薯汁30 g/L+香蕉汁30 g/L+活性炭0.1 mg/L,生根率为55.6%。驯化后将生根苗移栽于泥炭土∶黄心土∶珍珠岩∶钙镁磷肥(3∶2∶1∶0.2)的混合基质中,成活率85%。【结论】不同激素及浓度对千里香种子萌发和丛芽增殖过程影响显著,添加马铃薯汁和香蕉汁利于壮苗和生根培养。

关键词：千里香种子增殖壮苗生根离体再生体系

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