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1.
天然东北红豆杉种群生殖力与开花结实特性   总被引:3,自引:1,他引:2  
在黑龙江省穆棱东北红豆杉自然保护区,路线踏查到271株天然东北红豆杉,选择其中具有生殖活力(开花)的29雄株和30雌株作为样株,采用标准枝法对孢子叶球和结实状况及其与生态因子关系进行研究.结果表明:现实东北红豆杉天然种群中,♀♂性比为1:2;天然东北红豆杉有性生殖持续时间长,雄株胸径在1.5~92cm,雌株胸径在9.5~68.1 cm保持生殖状态,雄株较雌株早约20年进入花期;天然东北红豆杉小孢子叶球数量平均为大孢子叶球数量的3倍,大孢子叶球转化为果实的数量不足1/10,孢子叶球数量、结实数量与样株的胸径、冠幅、树高显著相关,与其他立地因子相关不显著;孢子叶球数量在冠层间的分布呈现由上至下的递减规律,而结实数量在冠层间沿中、上、下递减,结实率沿冠层自上而下递增;孢子叶球与结实数量在树冠不同朝向上也呈现出一定的特点,但总体上差异不显著.天然东北红豆杉的上述生殖特征的形成,既是物种本身与环境相适应的结果,也有动物和人类活动的影响.  相似文献   

2.
以东北红豆杉为研究对象,利用Li-6400便携式光合作用测定系统对其光合速率日变化、不同光照强度的光合生理响应及叶绿素荧光参数进行测定,结果表明:东北红豆杉雌株的光合速率日变化曲线呈单峰形,雄株呈双峰形,并具有明显的午休现象;东北红豆杉光饱和点为520μmol·m-2·s-1,光补偿点为13.769μmol·m-2·s-1,具有很强的耐阴性;雌株与雄株之间的叶绿素荧光参数最大的(潜在)光化学量子效率Fv/Fm基本相同,而激发能捕获效率Fv'/Fm'雌株较雄株略高。雌雄株之间的各参数Fv/Fm、Fv'/Fm'、qN、qP、φPsⅡ、ETR并无显著性差异,表明雌雄株光系统II(Ps II)的变化基本相同。  相似文献   

3.
曼地亚红豆杉(Taxus media)雌雄异株,树形美观,全株皆可提取紫杉醇,具有较高的药用和观赏价值。本文对四川洪雅地区曼地亚红豆杉2种雌株和1个无性系雄株的枝条和叶片形态特征进行了研究,结果表明:1枝条形态特征可作为雌雄性鉴定的标准之一:2个无性系雌株小枝近轮生,雌株1号节间长25 cm左右,每节分枝数为4个~5个;雌株2号较雌株1号的节间较短,仅为7 cm~8 cm,每节有7个~8个分枝;雄株1号侧枝排列在同一平面上,节间仅为3 cm~5 cm,每节有2个~3个分枝。2与2种曼地亚红豆杉雌株相比,雄株1号叶片更狭长,叶长、叶面积、叶形指数均大于2种雌株,而叶宽显著小于雌株。3雌株2号的单片叶鲜重量、干重量和比叶重量均低于雌株1号和雄株1号。综上所述,经过近20年的引种驯化,四川洪雅3种不同曼地亚红豆杉雌雄株的枝条和叶片形态特征存在显著差异,通过枝条和叶片形态特征对曼地亚红豆杉雌雄性进行鉴别,有利于生产栽植中的植株性别配置。  相似文献   

4.
知识博览     
印度天南星是属为数不多的变性植物之一,多年生草本植物,生长在温带与亚热带地区潮湿的林下或小溪旁。它有雄株、雌株和无性别的中性株3种类型。有趣的是,这些不同性别的植株可以互相转变,而动物中能变性1次。科学家长期研究和观察后发现,印度天南星的变性与植株体型大小密切相关,植株高度值以398毫米为界,超过这高度的植株,多数为雌株;小于这个高度的植株,多数为雄株。研究还发现,植株的高度在100~700毫米间,都可以发生变性,而380毫米却是雌株变为雄株的最佳高度。这是因为,植物在开花结实时,需要消耗大量营养物质,只有高…  相似文献   

5.
南方红豆杉人工授粉   总被引:1,自引:0,他引:1  
南方红豆杉是雌雄异株,异花授粉植物,在自然条件下雄株多,雌株少。在天然群落中雌雄比例约为1∶9,只有在雌雄株混生的地方才能采集到种子。大多数雌株每年都生产一些种子,但丰年的频率不多,一般6~7年才有一个丰年,这可能是由于物种间隔离(散生于林中)或花期不遇(雌雄异株、异花授粉),致使传粉受精受阻,种子产生数量较少。南方红豆杉雄、雌株开花时间与气候温度有关,景德镇地区、上饶地区、  相似文献   

6.
选择东北红豆杉为研究对象,根据野外74条样带的调查结果、14块野外植被样地调查结果和6株东北红豆杉解析木资料,系统研究黑龙江穆棱东北红豆杉自然保护区的天然东北红豆杉种群的资源特征、群落特征及生长规律。  相似文献   

7.
南方红豆杉的生理学特征与开发利用前景   总被引:1,自引:0,他引:1  
阐述了南方红豆杉生理学特征是雌雄异株、异花授粉植物,在自然条件下雄株多,雌株少,在天然群落中雌雄比例约为1:9左右,探讨了在雌雄株混生的地方采集种子以及种子繁育的关键技术.  相似文献   

8.
2005年4月对黑龙江省穆棱东北红豆杉(Taxus cuspidata Sieb.etZucc.)天然林分的组成结构、立地条件、及种群年龄结构。进行了调查研究。结果表明,该地区东北红豆杉种群生存的林分结构以天然针阔混交林为主,土壤含水量较高(40%-60%),pH值偏酸(4.7~5.5);野生东北红豆杉的种群结构不合理,属于衰退种群,这也是导致野生东北红豆杉种群下降的原因之一。虽然穆棱地区的立地条件适合东北红豆杉野生种群的生长,但目前成年东北红豆杉树干中空、腐烂,中等胸径的健壮成年树被盗伐,而且幼树经常被野生动物啃食,该地区东北红豆杉的种群仍然是下降趋势,处于濒危状态。  相似文献   

9.
刘彤  周志强 《林业研究》2006,17(2):132-134
在74条样带436.872hm2面积上进行野外调查,对黑龙江穆棱东北红豆杉自然保护区内天然东北红豆杉种群数量、种群分布与生态因子的相互关系进行了研究。结果表明:在保护区34544hm2范围内天然东北红豆杉种群数量庞大,而且天然东北红豆杉种群的分布对海拔、坡向、坡位和坡度等生态因子具有选择性。700m-800m是种群的最适海拔范围;分布在阴坡的天然种群数量明显高于阳坡;山地的中部和上部更适合东北红豆杉生长;东北红豆杉种群多数分布在坡度15度以下的山地,随着坡度的增加,天然种群的数量明显减少。图3表4参18。  相似文献   

10.
薛志勇 《云南林业》2002,23(2):17-17
银杏是异花授粉植物,雌雄不同株。雌雄株搭配不当会造成授粉不良,这是许多银杏园产量低的主要原因。银杏雌雄搭配的合理比例为20∶1或25∶1。但银杏在开花前很难区分性别。这对银杏的栽培十分不利。银杏性别早期鉴定有多种方法,现将2种农村较为适用的鉴别方法介绍如下,供栽培者选用。1形态鉴定法1.1看主干枝夹角雄株主干枝较挺直向上,分枝夹角为30°左右;雌株主干枝分枝下垂平展,夹角为50°左右。1.2看芽、叶分化时间雄株花芽分化早,落叶晚;雌株花芽分化迟,落叶早。1.3看叶形雌株叶缺刻浅且比雄株叶小些,雄株则正好相反。1.4看树…  相似文献   

11.
In many dioecious plants, gender affects economic value, breeding schemes and opportunities for commercial harvests. Hippophae rhamnoides L. is a dioecious plant species in which female genotypes are commercially preferred over male genotypes. Its berries have rich medicinal, nutritional and pharmaceutical properties because of their large amounts of vitamins, essential oils, proteins, fatty acids, free amino acids and flavanoids. Primary limitation for breeding H. rhamnoides L. is its dioecious nature, since gender cannot be identified by traditional methods. Therefore, some reliable and quick methods need to be developed. This communication deals with the development of isozyme and RAPD markers for early sex identification in this dioecious tree. The isozyme analysis was conducted with four enzyme systems, viz. peroxidase, esterase, malate dehydrogenase and catalase. The peroxidase enzyme system produced a female specific sex marker, which successfully differentiated between the staminate and pistillate genotypes of H. rhamnoides L. Thirty five random decamer primers were used in our study and one male sex linked marker was identified. OPD-20 (5′-ACTTCGCCAC-3′) displayed a band at 911 bp that expressed polymorphism between male and female genotypes. The staminate and pistillate genotypes could be distinguished using RAPD marker OPD-20911. These results revealed the immense potential of peroxidase isozyme patterns and RAPD as genetic markers for sex identification in H. rhamnoides L.  相似文献   

12.
一种有效的蚜虫基因组DNA提取方法   总被引:4,自引:1,他引:4       下载免费PDF全文
蚜虫属于同翅目(Homoptera)蚜总科(Aphidoidea)和球蚜总科(Adelgoidea),世界上已知种类为4 000多种[1],我国已报道的种类1 000余种[2]。蚜虫大多数是害虫,它们刺吸植物汁液,直接影响植物生长,同时间接传播病毒病害,造成农业上的损失,如棉蚜(Aphis gossypiiG lover)、麦长管蚜(Macrosiphum avenae(Fabricius))等;少数种类如五倍子蚜(Schlechtendalia chinensis(Bell))是重要的资源昆虫,具有较高的经济价值[3]。蚜虫身体微小,形态变异大,生活习性复杂,并具有多型多态现象,研究它较为困难,尤其是在分类和鉴定、近缘种的识别等方面,传统的研…  相似文献   

13.
Salix matsudana Koidz. cultivar 'Tortuosa' (corkscrew willow) is characterized by extensive stem bending and curling of leaves. To investigate the genetic basis of this trait, controlled crosses were made between a corkscrew female (S. matsudana 'Tortuosa') and a straight-stemmed, wild-type male (Salix alba L. Clone 99010). Seventy-seven seedlings from this family (ID 99270) were grown in the field for phenotypic observation. Among the progeny, 39 had straight stems and leaves and 38 had bent stems and curled leaves, suggesting that a dominant allele at a single locus controls this phenotype. As a first step in characterizing the locus, we searched for amplified fragment length polymorphism (AFLP) and randomly amplified polymorphic DNA (RAPD) markers linked to the tortuosa allele using bulked segregant analysis. Samples of DNA from 10 corkscrew individuals were combined to produce a corkscrew pool, and DNA from 10 straight progeny was combined to make a wild-type pool. Sixty-four AFLP primer combinations and 640 RAPD primers were screened to identify marker bands amplified from the corkscrew parent and progeny pool, but not from the wild-type parent or progeny pool. An AFLP marker and a RAPD marker linked to and flanking the tortuosa locus were placed on a preliminary linkage map constructed based on segregation among the 77 progeny. Sectioning and analysis of shoot tips revealed that the corkscrew phenotype is associated with vascular cell collapse, smaller cell size in regions near the cambium and less developed phloem fibers than in wild-type progeny. Identification of a gene associated with this trait could lead to greater understanding of the control of normal stem development in woody plants.  相似文献   

14.
以日本福岛县林业试验场日本柳杉种子园的 24个无性系为材料,利用 PCR—RAPD法和同功酶分析法对日本柳杉无性系的识别方法进行了比较研究。结果显示:同功酶法和由7个标记构成的RAPD分析法不能完全识别24个无性系,用17个和27个标记构成的RAPD分析法识别这24个无性系是可能的;同功酶标记是一种基因型标记,具有稳定性高的特点,适合于分析遗传构造的相似程度,特别适合于群体遗传分析,但是,由于能获得清晰话带的同功酶种类有限,在用于个体识别上比较困难;RAPD标记是一种显性标记,稳定性较差,但只要反应体系和条件稳定,利用RAPD标记正确进行无性系识别是完全可能的。  相似文献   

15.
The research in the genetics of sex determination and the differentiation of reproductive organs in flowering plants has long been a topic in recent years. Understanding the genetic and molecular mechanisms that control sex determination in flowering plants relies on detailed studies of the differentiation of sexual organs. Current theories about sex chromosomes have illuminated the mechanisms of plant sex determination. In addition, recent progress in cloning floral homeotic genes which regulate the identity of the floral organs has generated molecular markers to compare the developmental programs of male, female and hermaphrodite flowers in several species. In this review, the authors focus attention on these recent findings and provide a brief overview of the genetics of plant sex determination and the mechanism of sex determination gene expression and gene programs.  相似文献   

16.
Randomly Amplified Polymorphic DNA (RAPD) is easy to develop and simple molecular marker, but lack of reproducibility makes it less reliable for authentication of herbal drugs. Besides RAPD, other popular PCR and non-PCR based markers like AFLP, ISSR, SSR and RFLP are also used for authentication. However, these also have disadvantages like use of radioactive isotopes, high cost and absolute requirement of sequence information. Therefore, it is a better option to improve the reproducibility of RAPD by converting RAPD amplicons into Sequence Characterized Amplified Region (SCAR) markers. SCAR markers are easy, reliable and reproducible thus, have an advantage over RAPD markers for authentication of medicinal herbs used in the preparation of traditional medicines. These markers however, have been developed for only a few medicinal herbs. This review is an attempt to evaluate critically the role of SCAR markers in authentication of medicinal herbs used in traditional formulations.  相似文献   

17.
By using the methods of random amplified polymorphic DNA (RAPD) and bulked segregate analysis (BSA), we identified markers that are linked to the sex determination in the dioecious Populus tomentosa. Male and female bulks were created through rough mixing equal amounts of its five individual DNA. A total of 88 primers were screened. Twelve primers produced clear patterns with at least one band that appeared to be polymorphic between the two bulks. Subsequently, five male and female individuals were analyzed with those 12 primers, and only S60 (ACCCGGTCAC) could generate a common 1800 bp DNA fragment in all five male individuals and male pool but not in any female individuals. It can be concluded that the gender of P. tomentosa is most likely connected to the S60-1800 bp DNA fragment and RAPD markers. S60, therefore, can be used for selecting the gender of P. tomentosa. __________ Translated from Journal of Central South University of Forestry & Technology, 2008, 28(3): 80–83 [译自: 中南林业科技大学学报]  相似文献   

18.
以东北林业大学帽儿山实验林场天然白桦为研究群体,通过分析其中有代表性的100株个体的纤维长度与RAPD分子标记间相互关联性,筛选出一条与长纤维长度相关性系统为0.6144、显著性达1%水平的片段"BFLR-16",对此片段进行克隆、测序后,并将其转化成与长纤维性状相关的SCAR标记。此标记对长纤维白桦的鉴定效率高达92%,说明此SCAR标记对长纤维个体具有高度特异性,与控制纤维性状长度的基因高度连锁,它的存在与白桦纤维长度的增加有明显的相关性。图6参16。  相似文献   

19.
近年来,RAPD、AFLP和RFLP等分子标记技术的应用,加速了油橄榄种质资源和育种研究的步伐。本文简述了分子标记在油橄榄品种鉴定、分类、种质的遗传与变异、分子标记连锁遗传图谱及基因定位和标记等方面的应用和取得的进展。并探讨了分子标记技术在油橄榄研究上存在的问题和应用前景。  相似文献   

20.
Acorus calamus is a highly valued medicinal plant with global distribution used in several drugs of health care systems. We evaluated the genetic diversity and population structure of 50 populations of A. calamus from different geographical regions in India through RAPD and chloroplast microsatellite markers. From the total screened 82 RAPD primers and 18 cpSSR primers, 10 RAPD and nine cpSSRs were found polymorphic. The selected 10 RAPD primers produced a total of 96 reproducible bands, out of which 65 wer...  相似文献   

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