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Summer Warming Limited Bud Output Drives a Decline in Daughter Shoot Biomass through Reduced Photosynthetis of Parent Shoots in Leymus chinensis Seedlings
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作者 Song Gao Ruocheng Xu +4 位作者 Lin Li Jiao Wang Nian Liu Johannes M.H.Knops Junfeng Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1667-1675,共9页
Understanding how summer warming influences the parent and daughter shoot production in a perennial clonal grass is vital for comprehending the response of grassland productivity to global warming.Here,we conducted a s... Understanding how summer warming influences the parent and daughter shoot production in a perennial clonal grass is vital for comprehending the response of grassland productivity to global warming.Here,we conducted a simulated experiment using potted Leymus chinensis,to study the relationship between the photosynthetic activ-ity of parent shoots and the production of daughter shoots under a whole(90 days)summer warming scenario(+3°C).The results showed that the biomass of parents and buds decreased by 25.52%and 33.45%,respectively,under warming conditions.The reduction in parent shoot biomass due to warming directly resulted from decreased leaf area(18.03%),chlorophyll a(18.27%),chlorophyll b(29.21%)content,as well as a reduction in net photosynthetic rate(7.32%)and the maximum quantum efficiency of photosystem II(PSII)photochemistry(4.29%).The decline in daughter shoot biomass was linked to a decrease in daughter shoot number(33.33%)by warming.However,the number of belowground buds increased by 46.43%.The results indicated that long-term summer warming reduces biomass accumulation in parent shoot by increasing both limitation of stoma and non-stoma.Consequently,the parent shoot allocates relatively more biomass to the belowground organs to maintain the survival and growth of buds.Overall,buds,as a potential aboveground population,could remedy for the cur-rent loss of parent shoot density by increasing the number of future daughter shoots if summer warming subsides. 展开更多
关键词 Warming parent shoot bud bank photosynthesis chlorophyllfluorescence leymus chinensis
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基于Adh基因家族序列的牡丹组(Sect.MoutanDC.)种间关系 被引量:38
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作者 林启冰 周志钦 +2 位作者 赵宣 潘开玉 洪德元 《园艺学报》 CAS CSCD 北大核心 2004年第5期627-632,共6页
测定了牡丹组 7个种 10个野生居群共 10份样品的全部Adh1A、Adh1B和Adh2基因序列。结合前人已报道的牡丹野生种的Adh基因序列 ,以芍药组 (Sect .Paeonia)和北美芍药组 (Sect.Oneapia)的种作外类群 ,用PAUP (4 0b 4a)计算机程序构建了... 测定了牡丹组 7个种 10个野生居群共 10份样品的全部Adh1A、Adh1B和Adh2基因序列。结合前人已报道的牡丹野生种的Adh基因序列 ,以芍药组 (Sect .Paeonia)和北美芍药组 (Sect.Oneapia)的种作外类群 ,用PAUP (4 0b 4a)计算机程序构建了牡丹组全部 8个种的Adh1A、Adh1B和Adh2基因树 (最大简约树和邻接树 ) ,同时进行了Adh1A、Adh1B和Adh2基因序列的合并分析。结果表明 ,牡丹组的 8个种分为两个具有 90 %以上自展值支持的单系分支 ,分别对应Stern (194 6 )根据形态划分的革质花盘亚组 (Subsect .Vaginatae)和肉质花盘亚组 (Subsect.Delavayanae)。在革质花盘亚组内 ,本研究结果支持银屏牡丹 (Paeoniasuffruticosassp .yinpingmudan)和凤丹 (P .ostii)、紫斑牡丹 (P .rockii)和四川牡丹 (P .decomposita)以及矮牡丹 (P .jishanensis)和卵叶牡丹 (P .qiui)各种之间有更近的亲缘关系 ,但有关牡丹复合体 (P .suffruticosacomplex)内各种间更进一步的关系还有待进一步研究。根据Adh基因树并结合前人的结果对牡丹组的种间关系进行了详细的讨论。 展开更多
关键词 Adh基因家族 基因序列 牡丹组 sect.MoutanDC. 种间关系
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AFLP Variation Analysis on the Germplasm Resources of Leymus chinensis 被引量:10
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作者 刘杰 朱至清 +2 位作者 刘公社 齐冬梅 李芳芳 《Acta Botanica Sinica》 CSCD 2002年第7期845-851,共7页
The fingerprints of 27 Leymus chinensis (Trin.) Tzvel accessions from different regions in China were generated and their genomic DNA variations were assayed via amplified fragment length polymorphism (AFLP). A to... The fingerprints of 27 Leymus chinensis (Trin.) Tzvel accessions from different regions in China were generated and their genomic DNA variations were assayed via amplified fragment length polymorphism (AFLP). A total of 537 DNA fragments were amplified ranging from 75-530 bp using 8 AFLP primer combinations, among which 89 (16.6%) were monomorphic and 329 (61.3%) were polymorphic. The average number of DNA band produced by each primer combination was 66.13 and the total polymorphic rate was 78.84%. PICs (polymorphic information contents) scores for AFLP ranged from 0.0-0.5 and the mean PIC was 0.216. PIC scores were maximum (0.5) for 8.5% of the AFLP markers. All the results revealed that there was rich polymorphism in genomic DNA of L. chinensis . A DNA molecular dendrogram was established for 27 L. chinensis genotypes based on genetic variation and UPGMA cluster analysis of 537 AFLP markers amplified by 8 primer combination, suggesting that the genetic variation with high frequency showed close correlation with their ecotopes and geographical distributions. Twenty_seven L. chinensis genotypes could be divided into four groups. Among them the lower genetic relationship was shown. The reason of high genetic variation frequency in L. chinensis species and formation of varieties was discussed. 展开更多
关键词 leymus chinensis AFLP genetic relationship
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Circumscriptions and Phylogenetic Relationships of Primula Sects. Auganthus and Ranunculoides: Evidence from nrDNA ITS Sequences 被引量:3
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作者 郝刚 胡启明 李南淑 《Acta Botanica Sinica》 CSCD 2002年第1期72-75,共4页
The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. W... The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. We conducted a phylogenetic analysis using sequences from the ITS region of nuclear ribosomal DNA. All five species of these two sections and some representatives of other related sections were sampled. The ITS trees show that P. filchnerae could be convincingly placed in sect. Auganthus , together with P. sinensis Sabine ex Lindl. and P. rupestris Balf. f. et Farrer, whereas sect. Ranunculoides contains two species: P. cicutariifolia Pax and P. merrilliana Schltr. These two sections are distantly related and their association with other sections needs further studies. This study also demonstrated that ITS sequences would be a suitable marker for the reconstruction of Primula phylogeny. 展开更多
关键词 PRIMULA sect. Auganthus sect. Ranunculoides PHYLOGENY ITS PRIMULACEAE
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芍药属牡丹组(Paeonia sect.Moutan)种间关系的分子证据:GPAT基因的PCR-RFLP和序列分析 被引量:34
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作者 赵宣 周志钦 +2 位作者 林启冰 潘开玉 洪德元 《植物分类学报》 CSCD 北大核心 2004年第3期236-244,共9页
为了探讨芍药属牡丹组Paeoniasect.Moutan的种间关系 ,对采自 1 5个野生居群 ,代表牡丹组全部 8个野生种的 1 5份材料的GPAT基因片段 (外显子 5和 6之间 2kb的内含子 )进行了PCR_RFLP分析 ,并对代表牡丹组全部 8个野生种的 9份材料进行... 为了探讨芍药属牡丹组Paeoniasect.Moutan的种间关系 ,对采自 1 5个野生居群 ,代表牡丹组全部 8个野生种的 1 5份材料的GPAT基因片段 (外显子 5和 6之间 2kb的内含子 )进行了PCR_RFLP分析 ,并对代表牡丹组全部 8个野生种的 9份材料进行了测序。根据 1 2个限制性内切酶的PCR_RFLP数据 ,使用Network 3 .0计算机程序的RM (reduced_median)法建立了牡丹组种间亲缘关系网络树。同时根据 8个种 9份材料的GPAT基因片段序列 ,利用PAUP 4.0计算机程序建立了牡丹组GPAT基因的最大简约(MP)树和邻接 (NJ)树。结果获得了具有很高自展值支持、分辨良好的牡丹组种间关系 (GPAT基因 )树。最重要的是 ,该基因树所显示的牡丹组种间关系与根据形态学证据提出的牡丹组的种间关系基本吻合 ,并得到其他研究证据的支持。根据这一结果 ,对牡丹组的种间关系进行了详细的讨论。 展开更多
关键词 芍药属 牡丹组 野生居群 种间关系 GPAT基因 PCR-RFLP 序列分析
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羊草(Leymus chinensis)与灰色赖草(Leymus cinereus)及其杂交种(F_1)的抗旱生理特性比较 被引量:10
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作者 侯建华 云锦凤 张东晖 《干旱地区农业研究》 CSCD 北大核心 2004年第4期131-134,共4页
用不同浓度的聚乙二醇(PEG6000)进行根际水分胁迫处理,研究羊草(Leymuschinensis)、灰色赖草(Leymuscinereus)及其杂交种的抗旱生理特性。结果表明,在15%PEG、25%PEG、35%PEG不同处理下,两亲本及其杂交种叶片相对含水量(RWC)逐渐降低;... 用不同浓度的聚乙二醇(PEG6000)进行根际水分胁迫处理,研究羊草(Leymuschinensis)、灰色赖草(Leymuscinereus)及其杂交种的抗旱生理特性。结果表明,在15%PEG、25%PEG、35%PEG不同处理下,两亲本及其杂交种叶片相对含水量(RWC)逐渐降低;相对电导率、丙二醛含量(MDA)逐渐增加;超氧化物歧化酶活性(SOD)在15%PEG、25%PEG处理下,活性逐渐增加,在35%PEG处理下,活性开始下降。而且在15%PEG、25%PEG处理下,杂交种的抗旱(耐旱)性与亲本羊草相近,明显大于另一亲本灰色赖草。 展开更多
关键词 杂交种 羊草 抗旱生理 PEG处理 亲本 赖草 耐旱 水分胁迫 SOD 叶片
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Molecular Cloning and Sequence Analysis of Class Ⅱ Chitinase Gene in Leymus chinensis 被引量:5
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作者 金华 安晓雯 姜国斌 《Agricultural Science & Technology》 CAS 2009年第4期96-100,共5页
[ Objective] The aim of this study was to clone Class Ⅱ chitinase gene in Leymus chinensis grown in saline land in Heilongjiang Province and analyze its sequence, which provided a foundation for further study on the ... [ Objective] The aim of this study was to clone Class Ⅱ chitinase gene in Leymus chinensis grown in saline land in Heilongjiang Province and analyze its sequence, which provided a foundation for further study on the biological function and application of chitinasa gene. [ Method] cDNA library of Leymus chinensis leaves were constructed, and its DNA sequence was determined or analyzed, while the homology of chitinasa gene and amino acid sequence was compared with that in GenBank. [ Result] One full length cDNA fragment with length of 996 bp was cloned from cDNA library of Leymus chinensis leaves. The length of ORF was 768 bp encoding 225 amino acids (GenBank accession number: EU344908). The encoding products lacked CBD and C-terminal extension region from the view of structure, but had structural characters of Class Ⅱ chitinase gene, which indicated that amino acid sequence had high homology compared with Class Ⅱ chitinase gene of rye and wheat. The constructed recombinant vector pQE-LcChi2 could express a protein of 27 kD through induction, which was consistent with the deduced encoding product of pQE-LcChi2 gene. [ Conclusion] LcChl2 gene is an expression gene, which can express in E. coll. 展开更多
关键词 leymus chinensis Chitinase gene CLONING Sequence analysis
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知识联盟中的知识创新过程研究——对SECT模型的再认识 被引量:4
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作者 胡延平 刘晓敏 《经济与管理》 2008年第7期31-34,共4页
SECT模型只是对知识创新过程中的知识客体演变运动的轨迹进行刻画,而没有深入分析完成从知识转移到知识创新这一过程的主体——组织和个人进行知识创新的实际过程,同时,"场"理论中过于强调隐性只是与显性知识的区别,而没有看... SECT模型只是对知识创新过程中的知识客体演变运动的轨迹进行刻画,而没有深入分析完成从知识转移到知识创新这一过程的主体——组织和个人进行知识创新的实际过程,同时,"场"理论中过于强调隐性只是与显性知识的区别,而没有看到两者之间的联系,将知识创新过程分割地对应于不同阶段。基于不同等级和等级对知识划分,结合单环学习、双环学习与再学习的知识创新的一般过程,对SECT模型和"场"理论进行了修正,说明知识创新需经历SECT模型的不同阶段和相应"场"情景支持,但每阶段都会产生隐性知识和显性知识。 展开更多
关键词 知识创新 sect模型 “场”理论
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Research on Phenotypic Diversity of Different Populations of Leymus Chinensis in Zhalong Wetlands 被引量:2
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作者 杨晓杰 佟守正 李学花 《Agricultural Science & Technology》 CAS 2011年第9期1372-1375,共4页
[Objective] This paper aimed at revealing the rules of phenotypic variation of Leymus chinensis in Zhalong wetlands and providing the scientific and theoretical bases for devising protection strategies of Leymus chine... [Objective] This paper aimed at revealing the rules of phenotypic variation of Leymus chinensis in Zhalong wetlands and providing the scientific and theoretical bases for devising protection strategies of Leymus chinensis populations in Zhalong National Nature Reserve.[Method] Four phenotypic traits of five Leymus chinensis populations in Zhalong Wetlands were comparison and analysis using principal component analysis method and UPGMA cluster analysis method.[Result] There were significant differences among the four phenotypic traits of five populations,the order of coefficients of variation were node number〉plant height〉leaf width〉leaf length;the order of variation degrees of the populations from large to small was KQH,MD,JZ,ZK,TTG population.Results of principal component analysis suggested that the four traits were all factors led to the phenotypic differences among the populations of Leymus chinensis.Leymus chinensis of five populations were divided into three groups by cluster analysis,MD,JZ and TTG were classified as one group,KQH and ZK population were individually classified as one group.[Conclusion] Leymus chinensis had large-scale phenotypic variations and showed strong adaptability to different habitats,which was very important for selection,breeding of fine varieties and germplasm conservation. 展开更多
关键词 Zhalong leymus chinensis VARIATION Phenotypic diversity
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Variation of Water-Use Efficiency of Leymus chinensis and Cleistogenes squarrosa in Different Plant Communities in Xilin River Basin, Nei Mongol 被引量:6
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作者 陈世苹 白永飞 韩兴国 《Acta Botanica Sinica》 CSCD 2002年第12期1484-1490,共7页
Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar delta C-13 values, an indicator of long-term intercellular carbon d... Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar delta C-13 values, an indicator of long-term intercellular carbon dioxide concentration and thus of water-use efficiency (WUE) in plants, were measured on Leymus chinensis (Trin.) Tzvel. and Cleistogenes squarrosa (Trin.) Keng. in six communities of different habitats in die Xilin River Basin. The foliar delta C-13 values of both species tended to increase with decreasing soil water content (SWC) and a significant negative correlation was found between foliar delta C-13 Values and SWC in different soil layers, indicating that the two species could change WUE according to water availability. We also found relatively constant leaf water contents (LWC) of the two species in different habitats. Our results implied that the two steppe species might have adapted to different soil water regimes either through adjusting stomatal conductance to get a proper WUE, or through enhancing the osmosis-regulating ability to keep a relatively stable LWC. Our findings could partially explain why the two plant species have a wide distribution range and become dominant in the Xilin River Basin. 展开更多
关键词 Xilin River Basin leymus chinensis Cleistogenes squarrosa water-use efficiency delta C-13 value
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刈割对典型草原地带羊草(Leymus chinensis)的影响 被引量:21
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作者 仲延凯 孙维 包青海 《内蒙古大学学报(自然科学版)》 CAS CSCD 1998年第2期202-213,共12页
经过11年不同时期刈割和不同轮割研究结果表明:在羊草的抽穗期(6月23日)、开花期(7月8日)、结实期(8月2日)、结实后期(8月16日)和果后营养期(9月12日)刈割,对羊草在群落地上生物量中所占的比例、羊草生物量... 经过11年不同时期刈割和不同轮割研究结果表明:在羊草的抽穗期(6月23日)、开花期(7月8日)、结实期(8月2日)、结实后期(8月16日)和果后营养期(9月12日)刈割,对羊草在群落地上生物量中所占的比例、羊草生物量、密度、高度均产生不同程度的影响,总的趋势是波动式地下降.随着刈割时间的后移,羊草生物量的分层结构呈现叶量上移,而茎量下移,对割草有利;它的N、P含量逐渐下降,在生长旺盛期K的含量增加,至后期下降.一年割两次(6月23日和9月12日)、一年割一次、割二年休一年、割一年休一年和对照(均为8月16日)5个处理,羊草在群落生物量中所占的比例、羊草生物量、密度、高度均随刈割次数的增多而有不同程度下降,并有一定的相关关系.羊草生物量的分层结构,随刈割次数的增多而层次减少.羊草N、P的含量有随刈割次数增多而增加的趋势,K的含量有一定的波动. 展开更多
关键词 草原 羊草 刈割 轮割 生物量
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Water Use of Leymus chinensis Community 被引量:6
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作者 宋炳煜 杨劼 +1 位作者 旭日 乌江雨 《Acta Botanica Sinica》 CSCD 2003年第10期1245-1250,共6页
Soil moisture of Leymus chinensis (Trin.) Tzvel. community has obviously stratified phenomena: the layer (0-40 cm) in which roots are concentrically distributed is directly influenced by precipitation and evapotranspi... Soil moisture of Leymus chinensis (Trin.) Tzvel. community has obviously stratified phenomena: the layer (0-40 cm) in which roots are concentrically distributed is directly influenced by precipitation and evapotranspiration. It can be called interaction layer of precipitation and evapotranspiration. The layer (40-120 cm), where water-storage capacity exchange lagged exchange of the root-layer water-storage capacity and the community evapotranspiration, can be called major water-storage layer. The layer (under 120 cm) can be called water relatively stable/balanced layer. The year 1996 was a normal flow year, and soil water had a surplus of 18 mm at the end of the growing season. The year 1998 was a high flow year, because leakage took place under continuous heavy rainfall, soil water had a deficit of 15 mm at the end of the growing season. Transpiration to evapotranspiration ( T/ET) value reflected not only the luxuriance degree of the community, but also the water use regime of the environmental resources. T/ET value was low (0.5) in May 1998, reaching 0.7 in June, then decreasing to 0.6 in July, due to the impact of rainfall inclining, while August reached the maximum (0.9), and September decreased to 0.6. Water use efficiency (WUE) was mainly restricted by the growing rate of plants under sufficient water condition (1998). Its seasonal changes were coincident with the grand period of growth of the plants. When both meanings of WUE and T/ET were analyzed profoundly, the concept of evapotranspiration efficiency (ETE) which can all-side reflect utilization regime of the environmental water resources was advanced. 展开更多
关键词 leymus chinensis community water use efficiency (WUE) transpiration to evapotranspiration (T/ET) evapotranspiration efficiency (ETE)
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Fruit Anatomy of sect. Paracamellia with Reference to Their Significance of Germplasm Resources Exploitation 被引量:1
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作者 洪思思 张斯敏 +3 位作者 楼嘉 张薇 吕洪飞 廖芳蕾 《Agricultural Science & Technology》 CAS 2011年第5期643-646,共4页
[Objective] To utilize the germplasm resources,new systematic evidence for the classification of sect.Paracamellia,genus Camellia is found in this article.[Method] Fruit anatomy of 10 species representing sect.Paracam... [Objective] To utilize the germplasm resources,new systematic evidence for the classification of sect.Paracamellia,genus Camellia is found in this article.[Method] Fruit anatomy of 10 species representing sect.Paracamellia was investigated.And the main component of sect.Paracamellia in the genus Camellia was studied by MVSP software.[Result] The exocarp was thin;mesocarp was broad,having a large number of stone cells;endocarp was lignified,and separated easily from seed.The principle components analysis suggested that the distance between species was far,showing far relation;the current study did not support the formation of Camellia grijsii(C.grijsii)and Camellia yuhsienensis(C.yuhsienensis),Camellia shensiensis(C.shensiensis)should not be recognized as a variety of C.yuhsienensis.In addition,it also proved Ming's combining of Camellia confusa(C.confusa)and Camellia kissi(C.kissi)was unnatural.[Conclusion] The study provided theoretical basis for the development and application of sect.Paracamellia in the genus Camellia. 展开更多
关键词 Genus Camellia sect.Paracamellia Fruit anatomy Classification Germplasm resources
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羊草(Leymus chinensis)草地雨天放牧与非雨天放牧的绵羊采食特征 被引量:5
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作者 滕星 王德利 张宝田 《生态学报》 CAS CSCD 北大核心 2006年第3期762-767,共6页
通过受控实验,比较了雨天和非雨天放牧在采食方式、采食损失量、践踏折损率以及土壤含水量和容重的差异。得出雨天放牧条件下,羊草各种采食方式的比例降低,去顶量依旧随放牧压升高而增加,但与非雨天放牧不同的是不再占主要比例。羊草采... 通过受控实验,比较了雨天和非雨天放牧在采食方式、采食损失量、践踏折损率以及土壤含水量和容重的差异。得出雨天放牧条件下,羊草各种采食方式的比例降低,去顶量依旧随放牧压升高而增加,但与非雨天放牧不同的是不再占主要比例。羊草采食损失量与非雨天差异不大,对于适口性更高的植物,如芦苇和全叶马兰,雨天放牧时损失更高。绵羊在冷湿环境中活动明显减少,羊草的践踏折损率各放牧压下差异不大,但芦苇的折损率依旧表现为随放牧压增强而增加。放牧后土壤15cm的含水量都低于对照小区,表明绵羊践踏加速了土壤水分的蒸发。放牧后土壤容重与放牧前和非牧区差异显著,并且容重随放牧压增强而增加。 展开更多
关键词 绵羊 采食方式 践踏 羊草草地
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呼伦贝尔草原羊草(Leymus chinensis)光合速率的季节变化--以鄂温克旗牧业气象试验站为例 被引量:15
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作者 陈效逑 周萌 +1 位作者 郑婷 张荣菊 《生态学报》 CAS CSCD 北大核心 2008年第5期2003-2012,共10页
利用2005年和2006年5~9月对内蒙古呼伦贝尔草原鄂温克旗牧业气象试验站所在地羊草光合速率的系统观测数据,分析了羊草光合速率的季节变化和年际差异,及其与气象因子和土壤水分状况的关系。结果表明:(1)在整个生长季节内,羊草光合速率... 利用2005年和2006年5~9月对内蒙古呼伦贝尔草原鄂温克旗牧业气象试验站所在地羊草光合速率的系统观测数据,分析了羊草光合速率的季节变化和年际差异,及其与气象因子和土壤水分状况的关系。结果表明:(1)在整个生长季节内,羊草光合速率的变化大致呈三峰二谷的形式,峰值分别出现在返青期之后、夏季降水高峰期和秋季降水回升期。2005年光合速率的峰值明显大于2006年,前者夏季峰值的持续时间也明显长于后者,这与该年降水量较多、相对湿度和土壤含水率较高有关。(2)羊草的光合速率与测量当日前3~8d的累计降水量均呈显著正相关关系,2005年与测量当日前6d累计降水量的相关最显著,2006年与测量当日前3d累计降水量的相关最显著。与此相似,羊草光合速率与各层土壤含水率亦呈正相关关系,且2005年的相关程度一般明显优于2006年,其中,与0~20cm土壤含水率的相关系数最大,表明羊草光合速率主要受到20cm以上土壤水分的影响。(3)在水分条件较好、气温偏低的2005年,羊草光合速率与日平均气温之间呈微弱负相关关系,与相对湿度之间呈显著正相关关系,表明在水热组合满足羊草生长需要的情况下,相对湿度通过增加或降低气孔导度对光合速率产生显著的影响,而气温对光合速率的影响不大。在水分条件较差、气温偏高的2006年,羊草光合速率与日平均气温之间呈显著负相关关系,与相对湿度之间呈不显著正相关关系,这与水热组合失衡情况下气温升高加剧蒸发,使土壤水分亏缺有关。由此可见,土壤水分状况可能是羊草光合速率决定性的影响因素,而气温和相对湿度则是次生的影响因素。 展开更多
关键词 羊草 光合速率 季节变化 水热因子 呼伦贝尔草原
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温度对羊草(Leymuschinensis)生长及无性系分化的影响 被引量:8
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作者 杨理 杨持 《内蒙古大学学报(自然科学版)》 CAS CSCD 1996年第6期830-834,共5页
根据温室内的人为控制温度试验,观测温度对羊草(Leymuschinensis)无性系分化和生长的影响,得出如下结论;温度是影响羊草株高的最主要生态因子,适宜的高温显著促进单草的伸展;温度也是促进单草分蘖的主要因子之一... 根据温室内的人为控制温度试验,观测温度对羊草(Leymuschinensis)无性系分化和生长的影响,得出如下结论;温度是影响羊草株高的最主要生态因子,适宜的高温显著促进单草的伸展;温度也是促进单草分蘖的主要因子之一,羊草的生物量积累受到温度变化极值的限制,适宜的温度范围显著促进生物量积累.羊草无性系的分化和高温的天数明显正相关,无性系对高温有较强的生态适应性,甚至在高温已经抑制羊草生物量的积累的情况下,仍然对无性系的生长和分化有一定的促进作用,这充分表明了羊草无性系对温度有较强生态适应的特点. 展开更多
关键词 羊草 温度 无性系 生长 分化 禾本科
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普通小麦(Triticum aestivum)和毛穗赖草(Leymus paboanus)的杂交,杂种细胞无性系的建立及植株再生 被引量:4
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作者 张学勇 董玉琛 +1 位作者 杨欣明 李翠钗 《作物学报》 CAS CSCD 北大核心 1992年第4期258-265,T002,共9页
以3个普通小麦品种富可(Fuhuko)、中国春(Chinese Spring)及小偃759和毛穗赖草杂交,发现三个品种都可与毛穗赖草杂交,其中Fuhuko×L.paboanus平均结实率高达17.6%,杂种只有发育不全的幼胚而无胚乳。对杂种幼胚在N_6+1—2mg/11BA+0.... 以3个普通小麦品种富可(Fuhuko)、中国春(Chinese Spring)及小偃759和毛穗赖草杂交,发现三个品种都可与毛穗赖草杂交,其中Fuhuko×L.paboanus平均结实率高达17.6%,杂种只有发育不全的幼胚而无胚乳。对杂种幼胚在N_6+1—2mg/11BA+0.5mgGA_3或MS(其中NH_4NO_3含量降低一半)附加1mg/1IBA的培养基上进行保姆培养,部分幼胚发育成完整的小植株,大部分幼胚死亡,并且在MS(1/2NH_4NO_3)培养基上,两个胚(Fuhuko×L.psboanus)形成质量很差的小愈伤组织,对其进行改良培养,建立了两个杂种胚性无性细胞系(一个生长很快,另一个相对较慢)。杂种愈伤组织在附加1mg/1IBA的MS或N_6培养基以及附加(0.5mg NAA+0.5mgKT)/1的MS(1/2NH_4NO_3)分化培养基上均可高频率产生再生植株。同时发现:1.将MS培养基中硝酸铵的含量降低一半,可显著提高植株再生频率;2.降低分化培养基中生长素(如IBA,NAA)的含量,加入少量的细胞激动素(如0.5 mg/1KT)可促使大量胚状体萌发,产生正常植株,使绿苗中90.0%以上的植株来自胚状体发生途径。细胞学观察表明:幼胚直接成苗的杂种植株体细胞染色体数很稳定,2n=63+1B,和预期结果相符;而杂种愈伤组组再生植株染色体数极不稳定,不同株间染色体数不同,即使同一根尖中不同的细胞染色体数也有很大差异。 展开更多
关键词 小麦 毛穗赖草 杂种 植株再生
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赖草属(Leymus Hochst.)3种牧草营养器官耐旱结构的研究 被引量:7
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作者 王六英 赵金花 《干旱区资源与环境》 CSSCI CSCD 2001年第S1期-,共5页
本文对赖草属 3种牧草进行了营养器官抗旱结构的研究 ,发现了许多耐旱特性 :如营养器官维管束数目增多、后生导管的直径增粗 ;根、根茎的皮层薄壁组织环加宽 ;根茎、茎的薄壁贮藏组织面积增大 ;叶表皮泡状细胞列数增多、叶肉细胞呈短柱... 本文对赖草属 3种牧草进行了营养器官抗旱结构的研究 ,发现了许多耐旱特性 :如营养器官维管束数目增多、后生导管的直径增粗 ;根、根茎的皮层薄壁组织环加宽 ;根茎、茎的薄壁贮藏组织面积增大 ;叶表皮泡状细胞列数增多、叶肉细胞呈短柱状 ,大、中型维管束两端形成较宽的维管束鞘延伸区 ,维管束为由两层维管束鞘围成 ,为 C3 植物 ,与外表皮之间形成较宽的维管束鞘延伸区 ,内表皮下为较宽的薄壁细胞层 ,。 3种牧草中 ,大赖草的抗旱特性强于其它两种明显。 展开更多
关键词 赖草属 牧草 营养器官 耐旱结构
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Genetic Relationships Among Soluble Carbohydrates, Anthocyanins and Growth Characteristics in Leymus (Gramineae) Detected with Molecular Markers 被引量:3
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作者 胡赞民 Steven R. LARSON +1 位作者 Thomas A. JONES Richard R-C. WANG 《Acta Botanica Sinica》 CSCD 2002年第10期1173-1181,共9页
Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth and cold adaptation of cool-season grasses. The vrn-1 gene has potent effects on vernalization ... Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth and cold adaptation of cool-season grasses. The vrn-1 gene has potent effects on vernalization requirement, growth, and soluble carbohydrate accumulations of the winter-annual Triticeae species. Two hundred and four unmapped AFLP markers and genome-specific DNA markers genetically linked to the vrn-1 gene were used to detect QTL controlling soluble carbohydrate accumulations, anthocyanin coloration and growth characteristics in a segregating population derived from open pollinated Leymus cinereus x L. triticoides hybrids. These perennial Triticeae grasses are distinguished by adaptation and growth habit. As expected, positive trait correlations and pleiotropic gene effects were detected for soluble carbohydrate accumulations and anthocyanin coloration. Likewise, positive trait correlations and pleiotropic gene effects were detected for tillering, leaf development, leaf growth, regrowth and rhizome spread. However, soluble carbohydrate accumulations were not associated with attenuated growth. In fact, several DNA marker alleles, including one near vrn-Ns1, had positive effects on soluble leaf carbohydrate concentrations and low temperature growth. The corresponding DNA marker near vrn-Ns1 had more specific effects on tillering. We speculate that vrn-1 exerts quantitative effects on low-temperature soluble leaf carbohydrate accumulations and growth habit of the perennial Leymus. However, a number of other DNA markers displayed highly significant effects on soluble carbohydrate accumulations and various growth characteristics. Findings indicate that anthocyanin coloration may be a useful phenotypic marker for soluble carbohydrate accumulation. Although variation for soluble carbohydrates was not associated with attenuated growth in this population, this trait was under genetic control. 展开更多
关键词 leymus molecular markers genetic relationship
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不同改良措施对退化羊草(Leymus chinensis)草原的影响 被引量:13
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作者 杨丽娜 宝音陶格涛 《中国沙漠》 CSCD 北大核心 2008年第2期312-317,共6页
对1983年通过不同改良措施(播种羊草、耙地、围栏封育)处理过的退化羊草草原群落特征进行比较研究,结果表明:虽然经过23 a的恢复,土壤条件仍有差别,经过耙地处理土壤容重最小,含水量最高;三种改良措施的增产效果都很明显,播种羊草、耙... 对1983年通过不同改良措施(播种羊草、耙地、围栏封育)处理过的退化羊草草原群落特征进行比较研究,结果表明:虽然经过23 a的恢复,土壤条件仍有差别,经过耙地处理土壤容重最小,含水量最高;三种改良措施的增产效果都很明显,播种羊草、耙地、围栏封育的群落地上生物量比围栏外分别提高了127.30%、146.64%、138.04%;播种羊草和耙地处理的根茎禾草所占比例较高,而围栏外和围栏封育处理的丛生禾草所占的比例较高;三种改良措施中,旱生植物的绝对生物量都低于围栏外;耙地处理后群落多样性最高,而围栏外均匀性指数最高。综上所述:经过耙地改良所产生的效果维持时间最长,而播种羊草和围栏封育改良的后效依然存在。 展开更多
关键词 退化羊草草原 改良措施 功能群组成 多样性指数
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