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1.
植物次生物质在植物防御中的作用   总被引:2,自引:0,他引:2  
植物次生物质是植物对环境的一种适应,是在长期进化过程中植物与生物和非生物因素相互作用的结果。章阐述了植物次生物质在对环境胁迫的适应、植物与植物之间的相互竞争和协同进化、植物对昆虫的危害、草食性动物的采食及病原微生物的侵袭等过程的防御作用及其机制。  相似文献   

2.
清季中国近代海军之基在于福州船政,福州船政的兴衰系决于清廷发展海军的方针的演变,福州船政的兴衰和国防战略的演变则影响、决定着中国近代海军的兴衰。  相似文献   

3.
Studies were conducted under pot conditions to determine the comparative efficacy of carbofuran at 1 mg a.i./kg soil, bavistin at 1 mg a.i./kg soil, neem (Azadirachta indica) seed powder at 50 mg/kg soil, green mould (Trichoderma harzianum) at 50.0 ml/kg soil, rhizobacteria (Pseudomonas fluorescens) at 50.0 ml/kg soil against root-knot nematode,Meloidogyne incognita-wilt fungus,Fusarium oxysporum disease complex on green gram,Vigna radiata cv ML-1108. All the treatments significantly improved the growth of the plants as compared to untreated inoculated plants. Analysis of data showed that carbofuran andA. indica seed powder increased plant growth and yield significantly more in comparison to bavistin andP. fluorescens. Carbofuran was highly effective against nematode, bavistin against fungus,A. indica seed powder against both the pathogens and both the bioagents were moderately effective against both the pathogens.  相似文献   

4.
Shades of different light intensities (29%, 43%, 54%, 60% or 68%) along with control (no shade) were studied to observe their effects on the flowering time and plant quality. A hyperbolic relationship was observed between different light intensities under shade, and time to flowering. The total number of flower buds showed a curvilinear relationship with light intensities. Growth parameters related to the plant characteristics such as plant height, leaf area and plant fresh weight were improved under shading treatments at the expense of flowering time and number of flower buds. However, both linear and polynomial models applied assumed that cultivar Chimes White was equally sensitive to light intensity throughout development.  相似文献   

5.
The endangered medicinal herb,Changium smyrnioides can only be found in deciduous forest gaps within the middle to northern subtropical broad-leaved evergreen forest zone of China. The considerable plasticity of its shoot and root structure helps it to capture light more effectively in winter and early spring, and to adapt to the soil moisture conditions in its narrow habitat. Another medicinal plant,Anthriscus sylvestris, is of similar economic importance but commonly distributed widely. In contrast toC. smyrnioides, it has low structural plasticity. It is also specialized to adapt to the moist and sunny environment, where habitat, such as the banks of creeks and rivers, is abundant. Project supported by the National Basic Research Program (973) of China (No. G2000046805) and the National Natural Science Foundation of China (No. 39970058)  相似文献   

6.
Aquilaria agallocha can produce fragrant agarwood used for incense, traditional medicine and other products. An efficient plant regeneration system was established via organogenesis from shoots developed from seedlings ofAquilaria agallocha. Shoots generated many buds on MS medium supplemented with 1.3 μmol/L BA (6-benzylaminopurine) in the first 7 weeks, and the buds elongated on MS medium with 1.3 μmol/L BA+0.5 μmol/L NAA (naphthaleneacetic acid) in another 7 weeks, 2.3 shoots 2 cm in length per explant were obtained within 14 weeks. Plantlets were rooted on 1/2 MS medium after being immersed in 5 μmol/L NAA for 48 h, 96.7% of the roots grew up two weeks later. All plantlets that survived acclimatization grew well in the pots. Project supported by the National Natural Science Foundation of China (No. 30070066) and the Science and Technology Project of Guangzhou City (No. 2003J1-C0241), China  相似文献   

7.
Water hyacinth (Eichhornia crassipes (Mart.) Solms) is a prolific free floating aquatic macrohpyte found in tropical and subtropical parts of the earth. The effects of pollutants from textile wastewater on the anatomy of the plant were studied. Water hyacinth exhibits hydrophytic adaptations which include reduced epidermis cells lacking cuticle in most cases, presence of large air spaces (7∼50 μm), reduced vascular tissue and absorbing structures. Textile waste significantly affected the size of root cells. The presence of raphide crystals was noted in parenchyma cells of various organs in treated plants. Project (No. 30070017) supported by the National Natural Science Foundation of China  相似文献   

8.
In this paper,the existence,uniqueness,and asymptotic behavior of the solution of the density evolution equation for M/M/∞ model was studied by the semigroup theory of linear operators.  相似文献   

9.
The morphology and ultrastructure of Bullacta exarata spermatozoa observed by light and transmission electron microscopy are presented in this paper. The spermatozoon is composed of head with a simple acrosomal complex and an elongated nucleus, and tail with a midpiece, principal piece and an end piece. The midpiece consists of a mitochondrial ring, and the principal piece is composed of axoneme and lateral fin. The structure of B. exarata spermatozoa differs significantly from that of other gastropods, especially in the lateral fin and the principal piece, which was described scarcely before. A comparison is made between B. exarata and other gastropods, and its significance on reproductive evolution and physio-ecological adaptation is preliminarily discussed. Project supported by the Committee of Natural Science of Zhejiang Province (No. 398081) and Wenzhou Normal College (No. 2001Y15), China  相似文献   

10.
Embryogenic calli were induced from the seeds of creeping bentgrass (Agrostis palustris Huds.) cv. Regent and colonial bentgrass (Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4–7 days and then co-cultivated withAgrobacterium tumefaciens, LBA4404. which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR). After 3 days of co-cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4-D, 12–15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2–3 months of selection, the actively growing calli of ‘Regent’ and ‘Tiger’ were transferred to MS medium with 12–15 mg/L PPT and 250 mg/L cefotazime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.  相似文献   

11.
淮河源国家森林公园植物资源研究   总被引:2,自引:0,他引:2  
淮河源国家森林公园位于河南省西南部、桐柏山腹地,共有维管植物181科,785属,1886种及变种,具有丰富的中草药植物资源、观赏植物资源和许多珍稀濒危植物。森林植被垂直分布差异明显,植物种类多方交汇,南北兼容,有许多原始或古老的科属,是一个温带性质的植物区系,而且温带成分和亚热带到暖温带过渡类型突出,其植物的进化类型、生活型具有丰富的多样性。  相似文献   

12.
为了探索柑橘属植物叶脉序的特征在植物分类和生物进化上的意义,用脉络法对4种柑橘属植物叶脉序标本进行了比较研究.结果表明:柑橘属4种植物叶片脉序均为环结曲行羽状脉;一级脉直向行走或微弯曲行走,相对粗细一般为中等;叶脉分支一般为五级;盲脉无或1~2次分支;叶缘具三级脉环.4种植物叶片的脉序特征基本相似,在二级脉的数目和角度上略有变异,其二级间脉及三级脉类型、网眼的发育方式、尤其是盲脉的分支特点表现出高度的稳定性;而同种植物不同部位的叶,则完全一致.柑橘属中红橘、柚子、柠檬、血橙进化地位相似,脉序特征支持4种植物为同属植物.柑橘属植物叶片脉序特点是一个较为保守的特征,可以作为植物分类的依据.  相似文献   

13.
调查了福建省南靖乐土南亚热带雨林及周边药用蕨类植物有22科34属38种.其中桫椤为国家一级保护植物,风尾蕨科、乌毛蕨科、鳞毛蕨科为该区系的重点科,区系成分具古老性,保留有许多较原始的科,在系统发育上具有比较好的条件,在其进化上有连贯性.本区系有明显的热带性,同时具有强烈的热带南亚热带过渡性.分析了其植物区系组成和区系地理成分组成特点,对其利用价值进行了阐述,为进一步开发利用资源提出了建议.  相似文献   

14.
G蛋白在物种进化过程中具有高度保守性,不同的G蛋白有不同的基因编码.检测植物G蛋白多采用生化检测法和分子生物学检测法.植物G蛋白在光信号转导、激素信号转导和病原信号转导等方面有重要调控作用.  相似文献   

15.
16.
沈国明 《台州学院学报》2006,28(3):58-59,63
就光合作用色素-蛋白质复合体是否可以作为系统演化的证据谈了作者的看法。在低等植物类群藻类中,光合作用色素-蛋白质复合体特别是捕光色素-蛋白质复合体Ⅱ可以作为推测其彼此间亲缘关系的旁证;在高等植物中,其捕光色素-蛋白质复合体Ⅱ组成成分相同,说明它们在演化中的渊源性,从而为高等植物起源于同一生物类群提供旁证。  相似文献   

17.
Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial cultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.   相似文献   

18.
不同类群植物营养苗端的结构存在一定的差异.对维管植物营养苗端的结理论进行了综述;并探讨了苗端结构的演化与系统演化的关系.其趋势随着植物类群的演化等级表现为由简单到复杂,又由复杂到简化的螺旋式上升进化路线.  相似文献   

19.
Phytoremediation is emerging as a potential cost-effective solution for remediation of contaminated soils, and bioavailability of metal in the soil for plant uptake is an important factor for successful phytoremediation. This study aimed at investigating the ability of EDTA and citric acid for enhancing soil bioavailability of Cu and phytoremediation by Elsholtzia splendens in two types of soils contaminated with heavy metals [i.e. mined soil from copper mining area (MS), and paddy soil (PS) polluted by copper refining]. The results showed that addition of 2.5 mmol/kg EDTA significantly increased the H2O extractable Cu concentration from 1.20 to 15.78 mg/kg in MS and from 0.26 to 15.72 mg/kg in PS, and that shoot Cu concentration increased 4-fold and 8-fold as compared to the control. There was no significant difference between the treatment with 5.0 mmol/kg EDTA and that with 2.5 mmol/kg EDTA, probably because that 2.5 mmol/kg EDTA was enough for elevating Cu bioavailability to the maximum level. As compared with the control, citric acid had no marked effect on both soil extractable Cu and shoot Cu concentration or accumulation. The results indicated that EDTA addition can increase the potential and efficiency of Cu phytoextraction byE. splendens in polluted soils. Project supported by the National Natural Science Foundation of China (No. 29977017) and the Science and Technology Ministry of China (No. 2002CB410804)  相似文献   

20.
种子传播是指种子以某种方式离开母株到达适宜生境萌发成苗实现定居的过程.种子传播方式有主动传播、被动传播,后者有风力传播、水力传播、动物传播、人类活动传播.植物种子的传播方式在很大程度上是与其生活环境相适应的,不同的生境有与此相适应的种子传播方式,种子的形态结构特点常与其传播方式相适应.在长期的协同进化中,传播种子的动物与植物之间形成了互惠共生关系,这对维持群落结构及其稳定性具有重要的意义.  相似文献   

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