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1.
克拉玛依种子植物科属的区系地理成分分析 总被引：3，自引：2，他引：1
克拉玛依有种子植物44个科198属369种,通过对该地区种子植物科属的区系地理成分分析,表明该地区的种子植物单种科,单种属多,区系优势现象明显:本地区中的7种优势科,虽只占克拉玛依植物区系总科数的15.91%,但所含种数占总种数的67.75%。特有种比例低,珍稀濒危保护植物种类较少,且植物区系主要以温带为主:温带分布科占总科数的57.80%,植被分布符合该地区地带性特点。 相似文献
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通过对定西地区战国秦长城沿线种子植物调查,共统计到种子植物58科242属444种,其中裸子植物2科3属3种;被子植物56科239属441种。单种属的科共15个,超过10属的科5个,其总属数占调查总属数的45.5%,种数占调查总种数的52.4%,以菊科最多,共38属82种。科的区系分布类型共4个正型和4个变型。属的区系分布类型共13个正型和11个变型,中国特有属2个,分布在菊科（Compositae）和伞形科（Umbelliferae）。调查区域的植物种类相对丰富;地理成分比较复杂,以温带成分占优势,以北温带分布型和旧世界温带分布型为主;发现珍稀濒危植物2种。这为保护长城选择适宜的植物类群和代表性物种提供了理论依据。 相似文献
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大青山种子植物共有88科,391属,874种,其中裸子植物3科7属12种,被子植物85科,384属,862种。植物生活型多样,多年生草本占优势(65.22%),一二年生草本也占有一定比例(18.19%)。中生植物为主,占72.09%,旱生植物其次,占23.00%,由于生境的多样化,也有一些湿生和水生植物分布。地理成分复杂,东亚成分优势明显,蒙古成分也较多,反映出与周边地区的联系,温带亚洲、北温带、旧大陆温带成分均占有较高的比例,表现出明显的温带性质。 相似文献
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新疆鄯善种子植物物种多样性及区系分析 总被引：2，自引：2，他引：0
文中在形态分类学研究的基础上,对鄯善野生种子植物物种多样性与区系地理进行了分析。鄯善共有种子植物48科177属,296种2亚种1变种。科的组成中,就属水平而言,寡属科与多属科构成科结构的主体,所含属数占74.01%,而就种水平而言,则大科和寡种科为主体,所含种数占81.94%;属的组成中,单种属和寡种属构成属结构的主体,所含种数占88.63%。该区新疆特有种与中国新疆仅分布种占26.09%,比例较高。生活型以地面芽植物与一、二年生植物为主;生态型以旱生植物与中生植物占较大优势,占种数的77.92%,与其区系的温带干旱性质相吻合。属的分布区类型表明,该区系地理成分多样,有11个分布类型和10个变型,温带性质明显,约占72.3%,以北温带为主。 相似文献
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现场调查及统计结果表明:(1)鄱阳湖沙地种子植物共计115种,隶属于50科,92属,占江西省种子植物总科数的16.50%、总属数的7.47%、总种数的2.79%,双子叶植物占主导地位,多样性不丰富,在属、种层次上尤其突出;(2)科属组成都是以单种型占优势,科具有一定的优势现象,主要为禾本科、菊科、大戟科和蝶形花科植物,属优势现象不明显,分化程度低,植被组成简单,系统脆弱性强,易受自然和人为因素的影响,加剧土地的风沙化现象;(3)研究区沙地植物属的地理成分比科要丰富,但总体上,表现出很大的一致性,都具有明显的热带属性,无特有现象,这与其所在区域的热带性气候相符,此外,与其所在的庐山、赣西北区系相比较,具有明显的自身特点:热带性成分突出,温带性成分占从属地位,世界分布型属的比重相对较大。 相似文献
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阴山北麓是典型的草原向荒漠的过渡区,由于其物种组成、植物群落结构以及生态功能上的特殊性,具有较为丰富的物种组成和复杂的植物区系。采用植物区系地理学的理论与方法,以实地调查为主,通过查阅相关文献,对阴山北麓木本植物区系组成、地理成分进行分析。研究表明:阴山北麓木本植物区系由16科38属68种植物组成。该区系木本植物≥10种的优势科有3科,含2种的属和含1种的属物种较为丰富多达31属,占区系植物总属数的81.58%。植物科分布包含5个分布型和1个分布变型,以世界分布型占优势。植物区系地理成分分布有11个分布型和4个分布变型,以温带分布型占主导地位。 相似文献
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经初步查明,新疆乌恰县康苏肖尔布拉克自然保护区计种子植物65科282属635种(含亚种、变种),裸子植物3科3属12种,被子植物62科279属623种。对282属635种种子植物的地理成分分析表明,该地区植物分布区类型有12个型14个变型。其中,北温带分布有95属259种,占该地区植物总属、种数的40.25%和53.40%,表明温带属性是该地区植物区系的基本特点。同时,该地区植物区系与地中海―西亚―中亚及旧世界温带交流最多,其次与热带有一定的交流,而与温带亚洲和东亚交流很少。 相似文献
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内蒙古阿鲁科尔沁自然保护区有种子植物63科、215属、358种(含种下等级)。其中裸子植物1科1属1种,被子植物62科214属357种。植物生活型多样,多年生草本占优势(56.70%),一、二年生草本也占一定比例(27.93%),其余为木本植物。水分生态型以中生植物为主,占56.71%,旱生植物其次,占31.28%,由于生境的多样化,也有一些湿生和水生植物分布。地理成分比较复杂,东亚成分优势明显,蒙古成分也较多,反映出与周边地区的联系,温带亚洲、北温带、旧大陆温带成分均占有较高的比例,表现温带性质。 相似文献
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中国-巴基斯坦喀喇昆仑公路沿线植物区系 总被引：3，自引：0，他引：3
2009年9月对中巴喀喇昆仑公路沿线分布的植物和植被进行了考察,经初步整理和统计,该地区共有野生维管束植物52科223属489种。其中,蕨类植物1科1属1种,裸子植物2科2属5种,被子植物49科220属483种。对222属488种种子植物的地理成分分析表明,该地区植物分布区类型有10个正型13个变型。其中,北温带分布有86属227种,占该地区植物总属、种数的45.75%和61.36%,表明温带属性是该地区植物区系的基本特点。同时,该地区植物区系与地中海-西亚-中亚及旧世界温带交流最多,其次与热带有一定的交流,而与温带亚洲和东亚交流很少。 相似文献
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为了解准噶尔盆地南部农区野生饲用植物资源,调查研究了该区域野生饲用植物的科属组成及其生活型和生态型特点,并对其适口性和营养价值进行了分析。结果表明：该区共有野生饲用植物34科145属214种,优势科有禾本科(38属71种)、藜科(18属22种)、菊科(15属21种)、豆科(14属19种)、苋科(8属11种)、十字花科(8属10种);生活型植物以草本植物(1～2年生124种,多年生62种)为主,占86.92%,木本植物有28种,占13.08%;生态型植物以中生为主(183种)。依据适口性可将该区野生饲用植物划分为优、良、中、低4个等级,其中优等95种、良等77种、中等36种、低等6种。营养成分丰富且适口性较好的饲用植物主要集中在禾本科(21种)、豆科(17种)和藜科(13种)。 相似文献
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James F White Kathryn L Kingsley Qiuwei Zhang Rajan Verma Nkolika Obi Sofia Dvinskikh Matthew T Elmore Satish K Verma Surendra K Gond Kurt P Kowalski 《Pest management science》2019,75(10):2558-2565
Endophytes are microbes (mostly bacteria and fungi) present asymptomatically in plants. Endophytic microbes are often functional in that they may carry nutrients from the soil into plants, modulate plant development, increase stress tolerance of plants, suppress virulence in pathogens, increase disease resistance in plants, and suppress development of competitor plant species. Endophytic microbes have been shown to: (i) obtain nutrients in soils and transfer nutrients to plants in the rhizophagy cycle and other nutrient‐transfer symbioses; (ii) increase plant growth and development; (iii) reduce oxidative stress of hosts; (iv) protect plants from disease; (v) deter feeding by herbivores; and (vi) suppress growth of competitor plant species. Because of the effective functions of endophytic microbes, we suggest that endophytic microbes may significantly reduce use of agrochemicals (fertilizers, fungicides, insecticides, and herbicides) in the cultivation of crop plants. The loss of endophytic microbes from crop plants during domestication and long‐term cultivation could be remedied by transfer of endophytes from wild relatives of crops to crop species. Increasing atmospheric carbon dioxide levels could reduce the efficiency of the rhizophagy cycle due to repression of reactive oxygen used to extract nutrients from microbes in roots. © 2019 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
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Roger A. C. Jones 《Plant pathology》2022,71(6):1255-1281
What occurs when virus infection is spreading within a mixed plant species population? This question is important not only for economically significant, mixed species managed systems but also for environmentally significant mixed wild species populations. It received attention in recently published ecological studies on wild plant species, but these, and recent general pasture research publications, rarely mention earlier virus studies involving mixed species managed pasture. This review seeks to rectify that situation. It describes 10 diverse examples of past research on mixed species managed pasture done over two decades on three continents that demonstrated plant species balance changes arising from virus infection. These examples showed that plants belonging to susceptible pasture cultivars sensitive to systemic virus infection are sufficiently weakened that their ability to withstand competition from nonhost plants of other pasture species, or weed species, was diminished sufficiently to alter the plant species balance. Also, a similar alteration occurred when they were competing with virus-resistant or virus-tolerant host plants of the same or other pasture species, or a virus-resistant weed species. Such competition also diminished seed production, which decreased their ability to regenerate. Notably, as reported subsequently with wild plant species populations, when two different pasture species infected by the same virus compete with each other, growth of the more sensitive species is suppressed. Because managed mixed species pastures constitute an important component of regenerative agriculture, retaining an optimal balance of pasture species and delaying pasture decline from weed invasion both require effective management of virus diseases. 相似文献
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苜蓿盲蝽在豫东棉区的寄主选择及其转移规律 总被引：1，自引：0，他引：1
采用扫网、目测、盘拍和室内饲养方法,调查研究了河南东部棉区苜蓿盲蝽的野生寄主和栽培寄主植物种类,已发现161种,其中野生寄主植物137种,分属32个科,栽培寄主20种。研究了苜蓿盲蝽在这些寄主植物间的转移规律,表明该棉区以田菁、草木樨、野苜蓿为主的豆科植物及小白酒草为主的菊科等植物和小麦、棉花一起,构成了有利于苜蓿盲蝽发生的生态环境。抽穗期的小麦为越冬代成虫向棉田过渡的主要桥梁寄主,棉花仅仅是第1至第3代苜蓿盲蝽的侨居寄主,田菁、草木樨、小白酒草等豆科和菊科杂草丛生的地方是其第4代、第5代生存和越冬的主要场所。 相似文献
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伊犁野果林植物多样性及其保护 总被引：7，自引：3，他引：4
在中国仅分布于新疆伊犁，塔城等地的天山野果林是苹果，核桃，杏，李等多种果树的起源地之一，新疆野苹果，野核桃，野巴旦均已被列为中国濒危二级保护植物。根据多年的调查和采集，初步统计分布在伊犁野果林中仅种子植物就有４３０余种，其中野生果树植物有７科１７属４８种，此外还分布有许多苔藓类，地衣类以及大型真菌等丰富的微生物资源，野果林又是多种鸟类和动物活动，繁衍的优良栖息地。 相似文献
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棉铃虫寄主植物种类及其适合性程度 总被引：22，自引：1，他引：22
通过江苏淮南、淮北棉区棉铃虫寄主植物种类凋查,已查明60种栽培植物、34种野生植物为棉铃虫寄主,它们分属24个科,其中以禾本科、豆科、菊科、葫芦科、十字花科、锦葵科、百合科、旋花科、藜科种类居多。运用选择系数法和适合性指数法定量测定了30种常见寄主植物对棉铃虫的适合性程度,建立了选择强度与适合性程度估测模型,据此将棉铃虫众多寄主划分为适宜寄主、较适宜寄主与次要寄主三大类。并在上述工作基础上,结合寄主植物种植面积情况,明确了各代次棉铃虫主要栽培寄主种类,以优化棉铃虫测报与防治技术。 相似文献
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新疆霍城县大、小西沟野果林种子植物组成及资源 总被引：6，自引：2，他引：6
新疆伊犁霍城大、小西沟野果林是以野樱桃李群落为主的野果林,共有种子植物60科233属500余种.林区野生植物资源丰富,统计表明:有野生果树38种、食用植物30种、饲用植物60种、蜜源植物111种、观赏植物128种、香料植物50种、药用植物113种.其中包括国家重点保护植物9种;新疆维吾尔自治区重点保护植物9种;中国珍稀濒危保护植物3种.通过多次实地调查分析,阐明了霍城野果林野生果树的分布、繁衍规律和植被、生境状况;综述了植物资源类型和用途及野生樱桃李群系生存的濒危程度.并提出在霍城大、小西沟野樱桃李集中分布区建立自然保护区的建议. 相似文献
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内蒙古荒漠地区丛枝菌根植物的初步研究 总被引：5，自引：0，他引：5
本文对内蒙古荒漠建群及优势植物的丛枝菌根共生状况进行了调查。在观察的16科76种植物中,被丛枝菌根真菌侵染的植物有61(占79. 8% )种;其中多年生草本植物被丛枝菌根真菌侵染的比例较高,占94. 46%;而一年生和二年生的草本植物的比例仅65%。须根系植物中菌根植物约占91. 3%,高于直根系(75. 5% )。古地中海孑遗种四合木(Tetraenamongolica)、棉刺(Potaniniamongolica)、沙冬青(Ammopiptanthusmongolicus)和强旱生植物半日花(Helianthemumsoongoricum)有一定的菌根侵染。本地区野生植物的丛枝菌根形态结构类型多数为Arum类型,占83. 6%;而Paris类型少,只占3. 3%。丛枝菌根结构类型与植物的生活型、根系类型和侵染率无关。 相似文献
19.
China has made efforts to protect wild yak (Bos mutus) species and prevent the hybrids between wild yak and domestic yak (Bos grunniens) species.At present,wild yak population of a reasonable estimate would be over 70,000.Due to conservation efforts in environmental protection and ecological construction such as the Wildlife Protection and Nature Reserve Construction Project,the "Grain-for-Green" Project and the Natural Forest Resources Protection Project,the number of wild yaks is increasing.In general,Tibetan Plateau's ecosystem is getting better and its environmental quality shows a gradual improving trend.Tibetan Plateau is one of the world's cleanest regions called as the "Third Pole".In order to preserve the genetic pool of wild yaks,local pastoralists and polices drive off the wild male yaks from the domestic yak herds by making noise (banging washbasins,pots,etc.) or driving cars.Local government also incentivizes the culling of domestic yaks found in wild herds.For the sake of the biological and genetic features of this wild species,and the pastoralist way of life,wild yaks should continuously be protected to keep their genetic integrity.We appeal plans to investigate the gene pollution of wild yaks in some important distribution regions of this species.In the face of hybridizing with domestic yaks,proper guidance is urgently needed to address genetic pollution and protect the genetic integrity of wild yaks. 相似文献
20.
H. J. Moolman J. Van den Berg D. Conlong D. Cugala S. J. Siebert B. P. Le Ru 《Phytoparasitica》2013,41(1):89-104
The diversity of lepidopterous stem borers, their parasitoids and their associated wild host plants was studied in South Africa between 2006 and 2009 and in Mozambique between 2005 and 2010. In South Africa, 20 species of parasitoids were recovered from 17 stem borer species collected on 16 wild host plant species. From Mozambique, 14 parasitoid species were recorded from 16 stem borer species collected on 14 wild host plant species. The highest diversity of parasitoids was recorded on stem borers that attacked the host plants Phragmites australis (7 spp.) and Panicum maximum (6 spp.), in South Africa and Mozambique, respectively. Bracon sp. (Hymenoptera: Braconidae) and Procerochasmias nigromaculatus (Hymenoptera: Ichneumonidae) were the most recorded parasitoid species in South Africa while Cotesia sesamiae (Hymenoptera: Braconidae) parasitized most stem borer species in Mozambique. The most common tachinid parasitoid recorded in this study was Sturmiopsis parasitica (Diptera: Tachinidae). Parasitism of stem borers during the off season was previously thought to occur mainly in natural habitats but this study shows that although natural habitats provided refuges for some parasitoid species, stem borer parasitism was generally low in wild host plants, irrespective of whether collections were done during the cropping or off-season. Parasitoid beta diversity did not depend on habitat or host plant species, but was determined by stem borer diversity. 相似文献