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秋水仙碱诱导栝楼四倍体 被引量:9
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作者 吴玉香 杨福红 +2 位作者 赵晓明 何永波 李鹏飞 《核农学报》 CAS CSCD 北大核心 2009年第3期418-422,共5页
采用改良L.D.Cua法诱导短把栝楼获得四倍体,研究了0.2%浓度的秋水仙碱诱导短把栝楼染色体倍性变异的最佳处理时间、四倍体栝楼与原栝楼的形态特征及其四倍体与二倍体的细胞学鉴定。结果表明:0.2%秋水仙素的最佳处理时间为72 h,诱变率达8... 采用改良L.D.Cua法诱导短把栝楼获得四倍体,研究了0.2%浓度的秋水仙碱诱导短把栝楼染色体倍性变异的最佳处理时间、四倍体栝楼与原栝楼的形态特征及其四倍体与二倍体的细胞学鉴定。结果表明:0.2%秋水仙素的最佳处理时间为72 h,诱变率达82.1%。与二倍体相比,四倍体表现为:生长变缓;叶片增大、皱缩和变厚、叶形指数减小;叶片保卫细胞增大,气孔密度降低,叶绿体数目增加,叶色加深。根尖压片表明:二倍体的染色体数目为2n=66,大部分四倍体植株的染色体数目为2n=132,M2代部分四倍体植株也存在嵌合现象。 展开更多
关键词 栝楼 四倍体 改良l.d.cua
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秋水仙素处理对连翘生长的影响 被引量:3
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作者 王艳英 邓传远 +1 位作者 赵晓明 李海平 《蚌埠学院学报》 2014年第1期20-23,共4页
以二倍体连翘(Forsythia suspense(Thund.)Vahl)为材料,采用改良L.D.Cua法在0.2%秋水仙素浓度下对连翘幼苗顶芽进行不同时间的处理,观察处理组与对照组在形态学上的差异,探索秋水仙素诱导连翘的最佳处理时间。结果表明:连翘经秋水仙素... 以二倍体连翘(Forsythia suspense(Thund.)Vahl)为材料,采用改良L.D.Cua法在0.2%秋水仙素浓度下对连翘幼苗顶芽进行不同时间的处理,观察处理组与对照组在形态学上的差异,探索秋水仙素诱导连翘的最佳处理时间。结果表明:连翘经秋水仙素处理后,形态上与对照组存在显著差异,表现为植株变矮、叶片变厚、叶型指数变小,其中48 h差异最显著。并且得到了四倍体的连翘,其表现为叶下表皮气孔器变大、气孔密度下降、保卫细胞内叶绿体的含量增加。 展开更多
关键词 连翘 改良l d cua 秋水仙素
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牛膝多倍体的诱变及鉴定 被引量:1
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作者 李鹏飞 赵晓明 《山西农业大学学报(自然科学版)》 CAS 2009年第2期115-118,共4页
通过诱变牛膝多倍体,增加新的药用种质资源,为培育牛膝新品系奠定基础。以牛膝(Achyranthes bidentata Blume)为实验材料,研究了秋水仙素的诱变牛膝染色体倍性变异的最佳处理时间,多倍体的特征及其多倍体的细胞学鉴定。结果表明,当秋水... 通过诱变牛膝多倍体,增加新的药用种质资源,为培育牛膝新品系奠定基础。以牛膝(Achyranthes bidentata Blume)为实验材料,研究了秋水仙素的诱变牛膝染色体倍性变异的最佳处理时间,多倍体的特征及其多倍体的细胞学鉴定。结果表明,当秋水仙碱浓度为0.2%时处理最佳处理时间为24 h,诱变率达51.7%。变异株与对照株相比,变异株的生长变缓,叶片增宽变厚,叶色浓绿,叶片皱缩。根尖压片表明,对照株的染色体数为:2n =2x=42,变异株为2n=4x=84。 展开更多
关键词 牛膝 多倍体诱变 改良l.d.cua
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Appraisal of the Production-Oriented Approach: An Introduction 被引量:4
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作者 濮实 《Chinese Journal of Applied Linguistics》 SCIE 2017年第4期452-453,共2页
The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen, 2016). It is also motivated by the ... The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen, 2016). It is also motivated by the aspiration to enhance the quality of foreign language education in other similar pedagogical contexts outside China. A volume of research has been done by Wen Qiufang and her research team, to formulate the theory of POA and to test its effectiveness in classroom pedagogy (e.g. Wen, 2016, 2015; Yang, 2015; Zhang, 2015). At the moment, the POA is still at an early stage of theory building and almost all empirical research is done in the Chinese context. In order to improve the quality of this theory and to make it intelligible to the international academic community, a one-day symposium was held in Beijing Foreign Studies University on May 15, 2017. The symposium was entitled 'The first international forum on innovative foreign language education in China: Appraisal of the POA'. In the forum, leading experts in applied linguistics were invited to discuss the strengths and weaknesses of the POA and the directions for its future development. The symposium was the first attempt for the POA research team to discuss its latest work with international scholars. This Viewpoint section collects the responses of four experts who participated in the symposium, listed in alphabetical order. The collection of articles covers three topics related to the POA: its pedagogical application, its use for teacher training, and its research. Alister Cumming is Professor Emeritus and the former Head of the Centre for Educational Research on Languages and Literacies, University of Toronto, Canada. His article focuses primarily on POA research as an exemplary case of design-based research. Rod Ellis is Research Professor in the School of Education at Curtin University, Australia. He discusses POA in terms of pedagogy, teacher training and research, with both critiques and constructive suggestions. Paul Kei Matsuda is Professor of English and Director of Second Language Writing at Arizona State University, the writed states. He responds to POA from the perspective of an expert researcher and teacher of L2 writing. Charlene Polio is Professor and Associate Chair in the Department of Linguistics & Germanic, Slavic, Asian & African Languages atMichigan State University, the writed states. She conceptualises POA as a useful method to address some issues in pre-service teacher development. Overall, the articles in this section are insightful and reader-friendly. They are not only useful for the development of POA in particular, but may also be valuable to a broad range of researchers as they touch upon pertaining issues, as well as emerging topics, in the field of applied linguistics. We therefore find it necessary to make them accessible to a wide readership. 展开更多
关键词 The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen 2016). It is also motivated by the aspiration to enhance the quality of foreign language education in other similar pedagogical contexts outside China. A volume of research has been done by Wen Qiufang and her research team to formulate the theory of POA and to test its effectiveness in classroom pedagogy (e.g. Wen 2016 2015 Yang 2015 Zhang 2015). At the moment the POA is still at an early stage of theory building and almost all empirical research is done in the Chinese context. In order to improve the quality of this theory and to make it intelligible to the international academic community a one-day symposium was held in Beijing Foreign Studies University on May 15 2017. The symposium was entitled 'The first international forum on innovative foreign language education in China: Appraisal of the POA'. In the forum leading experts in applied linguistics were invited to discuss the strengths and weaknesses of the POA and the directions for its future development. The symposium was the first attempt for the POA research team to discuss its latest work with international scholars. This Viewpoint section collects the responses of four experts who participated in the symposium listed in alphabetical order. The collection of articles covers three topics related to the POA: its pedagogical application its use for teacher training and its research. Alister Cumming is Professor Emeritus and the former Head of the Centre for Educational Research on languages and literacies University of Toronto Canada. His article focuses primarily on POA research as an exemplary case of design-based research. Rod Ellis is Research Professor in the School of Education at Curtin University Australia. He discusses POA in terms of pedagogy teacher training and research with both critiques and constructive suggestions. Paul Kei Matsuda is Professor of English and director of Second language Writing at Arizona State University the writed states. He responds to POA from the perspective of an expert researcher and teacher of l2 writing. Charlene Polio is Professor and Associate Chair in the department of linguistics Germanic Slavic Asian African languages atMichigan State University the writed states. She conceptualises POA as a useful method to address some issues in pre-service teacher development. Overall the articles in this section are insightful and reader-friendly. They are not only useful for the development of POA in particular but may also be valuable to a broad range of researchers as they touch upon pertaining issues as well as emerging topics in the field of applied linguistics. We therefore find it necessary to make them accessible to a wide readership.
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