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Text clustering based on fusion of ant colony and genetic algorithms

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Frontiers of Electrical and Electronic Engineering in China 2009年第1期4卷 15-19页

作者： Yun ZHANG Boqin FENG Shouqiang MA lianmeng liu School of Electronics and Information Engineering Xi’an Jiaotong UniversityXi’an 710049China

Focusing on the problem that the ant colony algorithm gets into stagnation easily and cannot fully search in solution space,a text clustering approach based on the fusion of the ant colony and genetic algorithms is *** four parameters that influence the performance of the ant colony algorithm are encoded as chromosomes,thereby the fitness function,selection,crossover and mutation operator are designed to find the combination of optimal parameters through a number of iteration,and then it is applied to text *** simulation results show that compared with the classical k-means clustering and the basic ant colony clustering algorithm,the proposed algorithm has better performance and the value of F-Measure is enhanced by 5.69%,48.60%and 69.60%,respectively,in 3 test ***,it is more suitable for processing a larger dataset.

关键词： ant colony clustering genetic algorithm fusion text clustering

Infection and Colonization of Pathogenic Fungus Fusarium proliferatum in Rice Spikelet Rot Disease

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Rice science 2019年第1期26卷 60-68页

作者： SUN Lei WANG Ling liu lianmeng HOU Yuxuan XU Yihua LIANG Mengqi GAO Jian LI Qiqin HUANG Shiwen College of Agronomy Guangxi University State Key Laboratory of Rice Biology China National Rice Research Institute

Rice spikelet rot disease(RSRD), caused by Fusarium proliferatum, is an emerging disease. So far, the effects of diseased rice floral organs as well as the primary infection sites and stages of this pathogen are not determined. We investigated changes in the floral organs, along with the infection processes of the pathogen in plants inoculated with F. proliferatum and labelled with a green fluorescent protein during different growth stages of rice. The results showed that RSRD is not a systemic infectious disease, which has negative effects on the fertility of the infected rice. F. proliferatum caused brown colored anthers, crinkled pistils and ovaries, pollen grain deformities and anther indehiscence. The number of pollen grains on the stigmas decreased significantly in the infected spikelets, and the anther dehiscence and seed-setting rate successively declined by 69% and 73%, respectively, as a result of the infection. The initial infection stage occurred at the pollen cell maturity stage, and the primary invasion sites were determined to be the anthers of rice. It was noted that the pathogen mainly damaged the pollen cells, and with the exception of the filaments, proceeded to colonize the pistils and endosperm.

关键词： Fusarium proliferatum rice spikelet rot disease green fluorescent protein infection process infection stage invasion site

Identification and Evaluation of UV-Tolerant Streptomyces araujoniae Strain Isolated from Tibet Plateau Soil as Biocontrol Agent Against Rice Blast

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Rice science 2020年第5期27卷 359-362,I0013-I0017页

作者： liu lianmeng Zhao Yuan Lu Jiying Liang Mengqi Sun Lei Gao Jian Wang Ling Hou Yuxuan Huang Shiwen Cstate Key Laboratory of Rice Biology China National Rice Research InstituteHangzhou 310006China College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070China Agricultural College Guangxi UniversityNanning 530003China Plant Protection Station of Yulin Yulin 537000China Shaoxing Academy of Agricultural Sciences Shaoxing 312000China

Rice blast is the most important and destructive crop disease in rice paddies and poses a continued threat to the production of rice(Rossman et al,1990;Khush,2005;Wang et al,2018;Chen et al,2019).Biological control is given increasing attentions on the control of rice blast for its outstanding advantages,such as safety,low-cost,and sustainability and environmentally friendly *** Waksman&Henrici is an important actinomycete genus that is well known for its biological control *** is a relatively new species and known for its antagonistic effects against many phytopathogenic fungi(da Silva et al,2013).However,there is no report about the antagonistic efiect of *** on Magnaporthe oryzae,much less the disease control effects at the field experiment level.

关键词： Plateau continued control

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三唑类杀菌剂对水稻药害机理及解决方案

植物保护 2022年第4期48卷 107-113页

作者：黄世文刘连盟赵可菡章艺琳中国水稻研究所水稻生物学国家重点实验室杭州311401

三唑类杀菌剂(triazole fungicide,TFs)是一类广谱、高效、低残留、长效、内吸传导性好,同时具有保护和治疗作用的新型杀菌剂,对真菌性病害有较好的防控效果,在作物病害防治上被广泛应用。三唑类杀菌剂在防治水稻中、后期真菌性病害上... 详细信息

三唑类杀菌剂(triazole fungicide,TFs)是一类广谱、高效、低残留、长效、内吸传导性好,同时具有保护和治疗作用的新型杀菌剂,对真菌性病害有较好的防控效果,在作物病害防治上被广泛应用。三唑类杀菌剂在防治水稻中、后期真菌性病害上取得了极好的防效,是应用量较大的杀菌剂之一。但由于三唑类杀菌剂使用不当,在生产上造成了大量的药害实例,导致水稻减产或绝收,同时引起了一些社会问题,需要引起高度重视。本文在作者多年的调查和研究基础上结合相关文献资料,阐述了三唑类杀菌剂的分类、使用方法、作用机制,对水稻产生药害的原因、症状表现和机理,使用三唑类杀菌剂时避免发生药害的措施及药害发生后的补救方法。

关键词：三唑类杀菌剂水稻药害症状及机理解决方案

Screening for strains with high fumonisin production and strong pathogenicity of rice spikelet rot disease（RSRD）

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Screening for strains with high fumonisin production and str...

中国植物病理学会第十一届全国会员代表大会暨2018年学...

作者： Sun Lei Wang Lin liu lianmeng Li Qiqin Huang Shiwen College of Agronomy Guangxi University China National Rice Research Institute

The aim of this study is to establish a stable and efficient artificial inoculation technique to identify the pathogenicity of different strains for Rice Spikelet Rot Disease（RSRD）,and to test the ability of Fusarium proliferatum to synthesize fumonisin in two culture media by the detection method of *** on the methods,high fumonisin production and strong pathogenicity strains were *** and spraying inoculation methods were used to inoculate riceat booting and heading stages,and the pathogenicity and stability of different inoculation methods at different times were *** of pathogenicity and fumonisin production of different strains used the suitable inoculation methods and HPLC-MS/MS *** incidence of RSRD is high and stable by using injection inoculation during pollen mother cell meiosis to maturing stage,and the rice yield traits were significantly affected by inoculation during pollen mother cell formation to initial spike *** to this method,strong pathogenicity strains FP4,FP6,FP8,FP9 and FP10 were *** ability of fumonisin synthesiswas analyzed by using HPLC-MS/MS,the high fumonisin production and strong pathogenicitystrains FP4 and FP9 were selected *** culture medium was more suitable than corn culture medium for fumonisin synthesis of *** invasion time of RSRD was pollen mother cell formation to full heading stage,and the initial infection stage was pollen mother cell formation to meiosis stage,and the effect of RSRD on rice yield was closely related to infection *** results of this study provide a foundation for future disease prevention and pathogenic processes.

关键词： Rice spikelet rot disease Fusarium proliferatum Artificial inoculation Fumonisin Pathogenicity HPLC-MS/MS

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蚁群-遗传融合的文本聚类算法

西安交通大学学报 2007年第10期41卷 1146-1150页

作者：张云冯博琴麻首强刘连梦西安交通大学电子与信息工程学院西安710049

针对蚁群算法容易出现停滞现象而不能对解空间进行全面搜索的问题,提出了一种蚁群-遗传融合的文本聚类算法.该算法将影响蚁群算法性能的4个参数作为遗传算法中的染色体进行编码,基于此又设计出相应的适应度函数以及选择交叉变异算子,通... 详细信息

针对蚁群算法容易出现停滞现象而不能对解空间进行全面搜索的问题,提出了一种蚁群-遗传融合的文本聚类算法.该算法将影响蚁群算法性能的4个参数作为遗传算法中的染色体进行编码,基于此又设计出相应的适应度函数以及选择交叉变异算子,通过多次迭代找出最优的参数组合,并将其应用到文本聚类问题上.经与经典的k均值聚类算法、基本的蚁群聚类算法的仿真比较,结果表明所提出算法的聚类效果更好,在3个测试集上的F度量值要比k均值聚类算法分别提高5.69%、48.60%、69.60%,所以更适合于处理较大规模的数据集.

关键词：蚁群算法遗传算法融合文本聚类

SAPK10-mediated phosphorylation onWRKY72 releases its suppression on jasmonic acid biosynthesis and bacteria blight resistance in rice

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SAPK10-mediated phosphorylation onWRKY72 releases its suppre...

浙皖鄂地区水稻纹枯病菌5个种群的遗传结构分析

中国植物病理学会2019年学术年会

作者： Hou Yuxuan Wang Yifeng Tang Liqun Tong Xiaohong Wang Ling liu lianmeng Huang Shiwen Zhang Jian State Key Lab of Rice Biology China National Rice Research Institute

Bacterial blight caused by the infection of Xanthomonas oryzae ***（Xoo） is a devastating disease that severely challenges the yield of ***,we report the identification of a "SAPK10-WRKY72-AOS1" module,through which Xoo infection stimulates the suppression of JA biosynthesis to cause Xoo ***72 directly binds to the W-box in the promoter of JA biosynthesis gene AOS1,and represses its transcription via inducing DNA hypermethylation on the target site,which finally led to lower endogenous JA level and higher Xoo ***-inducible SnRK2 type kinase SAPK10 phosphorylates WRKY72 at Thr *** SAPK10-mediated phosphorylation impairs the DNA binding ability of WRKY72,and releases its suppression on AOS1 and JA *** work highlights a module of how pathogen stimuli lead to plant susceptibility,as well as a potential pathway for ABA-JA interplay with post-translational modification and epigenetic regulation mechanism involved.

关键词： Rice bacterial blight jasmonic acid SnRK2 WRKY

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生态学报 2010年第20期30卷 5439-5447页

作者：王玲黄雯雯黄世文刘连盟刘恩勇中国水稻研究所杭州310006 广西大学农学院南宁530003

水稻纹枯病是世界性的主要病害之一。目前对该病病原菌种群的遗传多样性研究不多,知之甚少,了解其种群的遗传结构可以增加对其进化历程的了解,以制定科学的防治策略。水稻纹枯病菌通常被认为是以无性克隆繁殖为主,但有研究报道它具有混... 详细信息

水稻纹枯病是世界性的主要病害之一。目前对该病病原菌种群的遗传多样性研究不多,知之甚少,了解其种群的遗传结构可以增加对其进化历程的了解,以制定科学的防治策略。水稻纹枯病菌通常被认为是以无性克隆繁殖为主,但有研究报道它具有混合繁殖方式。有关我国浙皖鄂地区水稻纹枯病菌种群的遗传多样性研究尚未见报道。为了解该地区水稻纹枯病菌种群的遗传变异、基因流、繁育方式及其遗传背景,采用ITS-5.8SrDNA测序技术,分析了分离自浙江富阳(FY)、安徽绩溪(JX)和巢湖(CH)以及湖北荆州(JZ)和孝感(XG)的5个水稻纹枯病菌种群75个菌株的遗传多样性。RhizoctoniasolaniAG-1IA是采集地区水稻纹枯病菌的优势类群。ITS-5.8SrDNA序列经测定共检测到78个多态位点,碱基A、T、C、G的平均含量分别为25.4%、33.6%、21.0%和20.0%。序列的平均转换与颠换比(Ti/Tv)为1.65,其中密码子第3位点的变异最高。根据序列的核苷酸变异共定义了29种单倍型,其中单倍型H5为5个种群的共享单倍型,占样本数的61.33%。5个种群的单倍型多样性和核苷酸多样性分别为0.627和0.482%,显示水稻纹枯病菌种群具有较高的遗传多样性。种群间固定化指数Fst为-0.0253-0.0170,基因流Nm为5.56-11.12,说明种群间基因交流频繁,基因流抑制了由遗传漂变引起的遗传分化,菌丝或菌核短距离扩散和带菌种子远距离传播增加了种群间的基因交流。AMOVA分析显示,种群间的遗传变异仅占总变异的19.03%,而80.97%的变异存在于种群内部,种群间的遗传分化很低。Mantel检验发现,遗传距离与地理距离无显著相关性(r=-0.241,P=0.499)。采用UPGMA法构建的单倍型间的系统发育树表明,不同地点的单倍型分支混合分布,这进一步验证了Mantel检验的结果。单倍型的网状分析显示,水稻纹枯病菌种群曾经发生过种群暴发而不断扩散,因还未能获得足够的时间建立更加复杂的结构故而呈非典型"星状"。采用中性检验分析了水稻纹枯病菌种群遗传结构,结果表明,种群间存在很强的自然选择作用,群体符合Hardy-Weinberg遗传平衡,说明水稻纹枯病菌群体是一个随机交配群体,具有以担孢子进行有性繁殖和以菌丝或菌核进行无性繁殖的混合繁殖方式。这种生物学特性可能是导致其在较小生态范围内较高的遗传多样性水平和较低的种群遗传分化的原因。另外,水稻纹枯病菌经有性繁殖产生新的基因型,并通过无性繁殖在群体内固定繁殖,这种遗传模式极有可能导致其进化潜能提高,极易对杀菌剂产生抗性。因此,对水稻纹枯病菌的防治,除了施用化学药剂和种植抗性品种外,还需要防治农田灌水引起的病原菌(菌丝和菌核)在地区间的流动传播,减少带菌种子迁移或农用机械的交叉污染,对水稻、大豆和玉米等寄主作物的种子进行播前处理等等,这些对于水稻纹枯病菌的防治也是极为重要的。

关键词：水稻纹枯病菌 ITS-5.8SrDNA序列单倍型种群遗传分化遗传多样性

SAPK10-mediated phosphorylation on WRKY72 releases its suppression on jasmonic acid biosynthesis and bacterial blight resistance in rice

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SAPK10-mediated phosphorylation on WRKY72 releases its suppr...