944 resultados para Chamaecrista desvauxii var. latistipula


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Eutrophication is becoming a serious problem in coastal waters in many parts of the world. It induces the phytoplankton blooms including 'Red Tides', followed by heavy economic losses to extensive aquaculture area. Some cultivated seaweeds have very high productivity and could absorb large quantities of N, P, CO2, produce large amount of O-2 and have excellent effect on decreasing eutrophication. The author believes that seaweed cultivation in large scale should be a good solution to the eutrophication problem in coastal waters. To put this idea into practice, four conditions should be fulfilled: (a) Large-scale cultivation could be conducted within the region experiencing eutrophication. (b) Fundamental scientific and technological problems for cultivation should have been solved. (c) Cultivation should not impose any harmful ecological effects. (d) Cultivation must be economically feasible and profitable. In northern China, large-scale cultivation of Laminaria japonica Aresch. has been encouraged for years to balance the negative effects from scallop cultivation. Preliminary research in recent years has shown that Gracilaria lemaneiformis (Bory) Daws. and Porphyra haitanensis Chang et Zheng are the two best candidates for this purpose along the Chinese southeast to southern coast from Fujian to Guangdong, Guangxi and Hong Kong. Gracilaria tenuistipitata var. liui Chang et Xia is promising for use in pond culture condition with shrimps and fish.

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In the current abalone hatchery in China, insufficient diatoms on vertically placed corrugated pvc plates at later stage often could not support the growth of postlarvae up to the stage that they can feed on live macroalgae. As a result, stripping the spats (35 mm) off by anaesthetization and switching the diet from live diatoms to artificial powdered diet in combination has to be performed in most of the abalone farms. This manipulation normally leads to more than 50% mortality. Here we report the direct use of the unicellular green alga Platymonas helgolandica Kylin var. tsingtaoensis as a potential alga to be used to settle the veliger larvae of the Pacific abalone Haliotis discus hannai and to feed the postlarvae. Settlement rate of 2-day-old veliger larvae in mono culture of P helgolandica could be as high as 92% ( +/- 4.2%) on day 10 in small scale trials, higher than that in the selected benthic diatom strain (53.6% +/- 12.7%) when settled in the water in which bacteria propagation was controlled by treatment of 2 ppm of benzylpenicillinum calcium and streptomycin sulfate. Postlarvae fed solely on P. helgolandica or the selected benthic diatom Navicula-2005-A grew at rates of 40.1 ( +/- 1.9) and 45.8 (+/- 13.4) mu m day(-1), respectively, when raised at 22 degrees C until day 50 postfertilization. P. helgolandica was shown to have distinct diurnal settling rhythm characterized with a peak of settled cells in the middle of the night for cell division and a peak of free-swimming cells in the middle of the day. High density of attached P. helgolandica cells on the inner surface of the culture facility in the night fits the nocturnal feeding behavior of the abalone spats. Judged by the promising larvae settling rate, growth and survival rates of the postlarvae fed with this alga, the free-swimming micro-green alga P. helgolandica constitutes a potential species for settling the veliger larvae and for supporting the growth of postlarvae as well. (c) 2006 Published by Elsevier B.V.

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本文以含有不同浓度海水的50%Hoagland培养液进行叶用甜菜(Beta vulgaris var. cicla L.)的无土培养,并研究了海水培养条件下叶用甜菜多种形态和生理特性的变化情况。结果表明,在电导率相当于22%海水的培养液中生长时,叶用甜菜植株形态和显微结构均无明显变化。在电导率相当于41%海水的培养液中生长时,叶用甜菜仍能保持存活和生长,显微观察也未发现死亡细胞,但植株形态和生理特性发生某些变化:(1)植株形态变化:植株叶面积大大减少,叶片增厚,栅栏组织细胞膨大,根毛变短;(2)植株干重降低,细胞渗透压提高,含水量增加(3)游离脯氨酸的含量比对照增加137%;(4)可溶性糖的含量基本未发生变化;(5)细胞膜电解质渗漏率增大,细胞内离子含量增加;(6)多肽成分变化:24.4KD2和7.0KD多肽的量明显增加;29.1 KD和29.5 KD多肽的表达量则有所减少等。结果表明至少海水培养液电导率相当于22%海水时,叶用甜菜能够正常的生和长,当培养液中盐度过高时,叶用甜菜的形态和生理特性发生某些变经,但仍能生存和长生。同时这些变化也说明叶用甜菜的耐盐性涉及多种生理生化过程,是由体内多种结构和功能协同进行的。

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[目的]介绍刺辩绿绒蒿的一个新变型.[方法]在青海省花石峡采集绿缄蒿属藏药时发现了刺瓣绿绒蒿(Meconopsis horridula var.spinulifera.)的一个白花新变型,与原变种(总状绿绒蒿Meconopsis horridula var.racemosa)进行了比较.[结果]在青海省玉树州玛多县花石峡生境为海拔4 200m的小河岸边阳坡草地上发现了刺瓣绿绒蒿的白花新变型,与原变种的区别在于花冠白色;花瓣两面中下部疏生细刺;花柱具4棱,棱呈膜质翅状,宽约1.5 mm;花丝窄线形.[结论]发现的刺瓣绿绒蒿新变型与原变型的主要区别是植物花冠呈白色.

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根据标本研究、野外考察和实验观察,对国产赖草属Leymus两个类群进行了分类修订,将阿尔金山赖草Leymus arjinshanicus D.F.Cui和L.aerginshanicus D.F.Cui ssp.ruoqiangensis(S.L.Lu&Y.H.Wu)D.F.Cui处理为若羌赖草L.ruoqiangensis S.L.Lu&YH.Wu的新异名,将纤细赖草L.secalinus(Georgi)Tzvel.vartenuis L.B.Cai提升为一个独立的种L.tenuis(L.B.Cai)L.B.Cai.

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报道了新疆赖草属2个新变种,即北疆赖草(Leymus tianschanicus(Drob.)Tzvel.varborealus L.B.Cai)和短穗赖草(Leymus angustus(Trin.)Pilger vat.brevistachyus L.B.Cai)。

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在整理蓝雪科标本时,发现了补血草属的一个新变种:玛多补血草(Limonium aureum Hill.var.maduoensis),生境为海拔4000 m以上的滩地紫花针茅高寒草原和盐碱化土壤中.

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在标本室研究和野外考察的基础上,对中国细柄茅属Ptilagrostis Griseb.几个类群进行了分类修订.双叉细柄茅P. dichotoma Keng ex Tzvelev和窄穗细柄茅P. junatovii Grub.分别被归并到细柄茅P.mongholica (Turcz. ex Trin.)和太白细柄茅P. concinna (Hook. f.) Roshev.中作异名;小花细柄茅P. dichotoma Keng ex Tzvelev var.roshevitsiana Tzvelev则被提升为种P. roshevitsiana (Tzvelev) L. B. Cai.

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风毛菊属Saussurea DC.是菊科物种分化十分剧烈和分类处理十分困难的一个属。该属的单系起源性质、属下分类系统以及一些独特形态物种的系统位置尚不清楚,有待进一步验证。本文测定了代表该属5个亚属37种植物43个样品和川木香属Dolomiaea DC.的1种样品的叶绿体DNA trnL-F序列,并调取菜蓟族Cardueae Cass.与风毛菊属具有一定亲缘关系的13属的该序列,一起进行了分支分析,重点验证该属的属下形态分类系统以及形态特殊、青藏高原地区特有的雪兔子亚属subgen.Eriocoryne中假雪兔子组sect.Pseudoeriocoryne的单系性质。研究结果表明:(1)尽管风毛菊属5个亚属形态变异极大,但种间的trnL-F碱基变异却非常小;(2)根据形态学划分的5个亚属在分支图上没有得到分辨;(3)根据无明显茎、叶呈莲座状包被头状花序等特征建立的假雪兔子组是一多系群,与其他雪兔子亚属的种类也没有密切的亲缘关系,其共同拥有的形态学特征分别起源了4次;(4)雪莲亚属假雪莲组subgen.Amphi- laena sect.Pseudoamphilaena中的多鞘雪莲s.polycolea变种尖苞雪莲S.polycolea varacuisauama与风毛菊亚属subgen.Saussurea的长毛风毛菊S.hieraciodies、美丽风毛菊s.superba、打箭风毛菊s.tatsienensis和重齿风毛菊s.katochaete具有一段长18个碱基的插入,但多鞘雪莲原变种和重齿风毛菊另一居群无此插入;这一插入在整个菜蓟族和风毛菊属中都十分特殊,是一次进化事件的结果,这一复合体的形态分化应该是在这一进化事件发生之后进行的;而尖苞雪莲和重齿风毛菊拥有这一特殊序列可能是由于杂交而导致种内存在不同的单倍性。研究结果证实青藏高原极端环境下即使在较低的分类等级——属内、种问的形态特征也存在相同选择压力下的生态趋同进化。这一点在利用形态特征研究该地区物种的亲缘关系和命名自然分类等级时应予以特别重视。风毛菊属提供了研究极端环境下物种快速分化、网状进化和趋同进化的典型范例。

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Oxytropis xinglongshanica C. W. Chang var. obesusi-corollata Y. H. Wu, var. nov. A var. xinglongshanica recedit corollis obesis, vexillis c. 15 mm longis, c. 10 mm latis, limbis late ovatis, unguibus c. 6 mm longis; alis c. 14 mm longis, c. 4.5 mm latis, limbis anguste obovatis.

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高原314是中国科学院西北高原生物研究所农业中心通过有性杂交培育的春小麦新品种,2001年12月通过青海省农作物品种审定委员会审定,品种原代号为95-314,现定名为高原314,属小麦Var. graecum Korn的变种。品种组合为:高原602 * {[ST142 * [(82宁182 * 82原11) * 47-2]] * [(78-17-3 * 83-228-3) * (Chanal * 338)]}F_3。

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本文提出了龙胆属两个种的新名称 (GentianamembranuliferaT .N .Ho,G .nudicaulis Kurz var.as samensisT .N .Ho )和 5个变种的新组合 [(Gentianalateriflora Hemsl.var.uncifolia (H.J.Lam)T.N.Ho,G.sumatranaRidl.var.humifusa (S .Moore)T .N .Ho ,G .quadrifariaBl.var.wightii(Kusnez.)T .N .Ho,G .loerzingiiRidl.var.timida (Kerr)T .N .Ho ,G .membranuliferaT .N .Hovar.recurvata (Kusnez.)T .N .Ho) ]。

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报道了采自青海南部7 种翠雀属(Delphiniun L.) 植物的染色体数目和核型。大通翠雀花D.pylzowii 的核型公式为2n= 16 = 2m + 4sm + 10st; 毛翠雀花D.trichophorum的核型公式为2n= 16 = 2m + 4sm + 10st; 蓝白翠雀花D.albocoerelum 的核型公式为2n = 16 = 2m + 4sm(2SAT) + 10st; 囊谦翠雀花D.nangchienense的核型公式为2n = 16 = 2m + 6sm + 8st; 唐古拉翠雀花D.tangkulaense 的核型公式为2n=16=2m(2SAT)+6sm+8st;单花翠雀花D.candelabrum var.monanthum 的核型2n=16=2m+6sm+8st;展毛翠雀花D.kamaoense var.glabrescens的核型公式为2n=16=2m+6sm+8st;前5种植物的染色体数目和核型为首次报道。

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对青藏高原高山冰缘地区毛茛科3 种特有植物的核型进行了分析。它们的核型公式(K)、染色体相对长度组成(C. R. L. ) 和核型不对称系数(A s. K% ) 分别为: 青藏金莲花 T rollius pumilus var. tangu ticus: K (2n) = 6m + 8sm (2SA T ) + 2st, C. R. L. = 4L + 4M 2+ 4M 1+ 4S,A s. K% = 63. 57, 核型属2B型; 甘青乌头A conitum tanguticum 为K (2n) = 6m + 10sm ,C. R. L. = 4L + 8M 1+ 4S,A s. K% = 62. 54, 2B 型; 单花翠雀花Delphinium candelabrum var.monanthum 为K (2n) = 6m + 8sm + 2st, C. R. L. = 4L + 4M 2+ 4M 1+ 6S,A s. K% = 64. 34, 属3B 型。经同相关近缘种核型资料比较, 青藏金莲花核型不对称性和进化程度比金莲花T.ch inensis 低; 甘青乌头的核型不对称性和进化程度在其近缘类群(乌头组Sect. Aconitum ) 已报道的种之内最低; 单花翠雀花核型不对称性和进化水平比翠雀组(Sect. Delphinastrum ) 已报道的展毛翠雀花D. kamaoense var. glabrescens、多枝翠雀花D. maxim owiczii 和蓝翠雀花D. caeruleum 都低。这与该3 种植物在王文采先生(1979) 中国毛茛分类系统中的位置是一致的。

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禾本科赖草属二新种及一新变种,即芒颖赖草Leymus aristiglumus L . B .Cai ,伊吾赖草Leymus yiwuensis L. B. Cai ex N. R. Cui 和疏节赖草Leymus secalinus var. laxinodis L . B . Cai 。