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131.
132.
133.
Julia F. Morton 《Economic botany》1991,45(3):318-333
The horseradish tree (Moringa pterygosperma,) is being introduced into drought-ridden lands to augment the local food and
fodder supply. The tree grows up to 5 m per year. The foliage is high in calcium and has half the oxalates of amaranth. Seeds
yield edible oil and the seed meal is used as fertilizer and as a coagulant to clarify turbid water. The philanthropic center,
ECHO (Educational Concerns for Hunger Organization), North Fort Myers, Florida, receives many requests for seeds. A missionary
in Mali wrote: “The seeds you sent arrived during the worst year of 14 years of dry weather. Only the moringa survived, and
they have flourished. ”Another seed shipment resulted, after harvesting a crop, in 25 000 trees being planted by university
students and faculty, around laborers’ houses in Maranhao, Brazil. The tree is not limited to tropical lowlands, but thrives
at elevations of 800-1200 m in protected mountain areas of southern Mexico. The long-range effects of ingesting various parts
of the tree as food or folkmedicine need study. Attention should be given to horticultural improvement, perhaps through hybridization
with one or more related species now being compared with M. pterygosperma in India and Africa.
ХРеНовое дерево, Moringa pterygosperma F. Gaertn. (Moringaceae), Дар сыхим землям. Хреновое дерево, Moringa pterygosperma,
вводится в бездождивые землии чтоб умножить местное снабжение пищи и корма. Дерево растет до 5 метров в год. Листья содержат
много кальцию и половину щавелев по сравнени#x044E; с амарантом. Семя дают съедобное масло и семеная мука употребляется как
одобрение и как коагулант для очищение мутной воды. Филантропический цэнтэр ECHO (Educational Concern for Hunger Organization,
North Fort Myers, Florida) полужает мното просьб чтоб получить семя. Один миссионер из Мали писал “Семя которые вы послали,
прибыли в самый сухой год за 14 лет сухой погоды. Только моринга пережила и цвела. Другая отправка семен была совершена после
получения урожая и 25000 деревьев были посажены студентами и учителями около домов рабочих в Маранхау, Брразилия.
Это дерево не ограаничевается тропическим климатом и преуспевает на уровне 800 до 1200 метров в защищенных горных местах южной
Мексики. 相似文献
134.
Reconstruction and analysis of human alu genes 总被引:39,自引:0,他引:39
135.
Thidiazuron stimulates shoot organogenesis and somatic embryogenesis in white ash (Fraxinus americana L.) 总被引:3,自引:0,他引:3
Sharon Bates John E. Preece Nadia E. Navarrete J. W. Van Sambeek Gerald R. Gaffney 《Plant Cell, Tissue and Organ Culture》1992,31(1):21-29
Immature and mature nonstratified seeds of white ash (Fraxinus americana L.) were dissected transversely and 2/3 of each seed was placed onto agar-solidified Murashige and Skoog medium. Adventitious buds, shoots, and somatic embryos formed on callus, cotyledons, and hypocotyls of the resulting seedlings. Shoot organogenesis was induced on explants cultured on medium with 10 M thidiazuron but not on explants on media with benzyladenine (BA) or isopentenyladenine. Not all seed sources were equally capable of shoot organogenesis and embryogenesis. Atypical of adventitious regeneration of other woody plants, mature seed explants of white ash were more organogenic with shoots that elongated better than explants from immature seeds. Somatic embryogenesis was observed in cultures where mature seeds were first cultured for 4 weeks on a medium containing 10 M adenine 2,4-dichlorophenoxyacetic acid in combination with 0.1 and 1.0 M thidiazuron, followed by transfer to a medium containing 0.05 M 6-benzyladenine and 0.5 M naphthaleneacetic acid. Adventitious shoots and epicotyls from both seedlings and germinated somatic embryos were rooted under intermittent mist and acclimatized to the greenhouse.Abbreviations BA
6-benzyladenine
- 2,4-d
2,4-dichlorophenoxyacetic acid
- IBA
indolebutyric acid
- 2iP
isopentenyladenine
- NAA
naphthaleneacetic acid
- TDZ
thidiazuron-N-phenyl-N-1,2,3-thiadiazol-5-ylurea
- WPM
woody plant medium 相似文献
136.
A Perspective on Protistan Nomenclature 总被引:1,自引:0,他引:1
ABSTRACT. The nomenclature of protists is more complicated than that of plants or animals because more than one code of nomenclature applies (i.e. the taxa may be ambiregnal), because of the frequent absence of type material, and because of changing perspectives of the phylogenetic relationships of various groups of protists. These factors often lead to uncertainty over the meaning of names of taxa. If nomenclatural instability is to be avoided, some changes in current practices are required. The nature of the problems and some possible changes are discussed. 相似文献
137.
Abstract. Woody vegetation was studied in 44 sites in Senegal. Species composition and density were analysed with TWINSPAN and Canonical Correspondence Analysis; 16 vegetation types were defined. A supervised, multispectral and multitemporal classification of day and night, dry season NOAA-AVHRR imagery was used to identify their distribution with a classification accuracy ranging from 60–100%. 相似文献
138.
本文综述了外生菌根的形态学和解剖学特征,评价了这些特征用于外生菌根分类的价值,同时指出各种类型的形态学特征和解剖学特征与其营养吸收的关系。这些特征包括了菌根的颜色类型及变化、形状及分枝方式、外伸菌丝的多少及特征、根状菌索有无及分化、菌核有无及特征、菌套内外表面的菌丝排列及分化,菌套的切面特征,丹宁层厚度及分化、哈氏网的菌丝排列及厚度等。较详细阐述了100多年来,人们为外生菌根分类所作出的种种努力,并对各种分类方式作了简单的评价。 相似文献
139.
系统树是描述物种、人种甚至基因间亲缘关系和演化的重要工具,必须以进化距离或(相对)替代率作为重要的参数。但以哪一个参数构建的树更能反映真实的系统树呢?事实上迄今并无人对此作过认真的研究。本文以模拟数据并用方差分析法检验两个参数的异同并讨论其包含的生物学意义。研究结果表明,当氨基酸的替代率和核苷酸的替代率分别为0.18和0.13时,它们的进化距离分别为0.199和0.143。经方差分析证实,若检验的氨基酸和核苷酸最大数目均为75只时,不论以替代率或进化距离中那一个作为构树参数,拓扑树事实上几乎只有一个。这就是说,该时拓扑树可靠性很大,而且随着它们替代率的减少,则检验的氨基酸和核苷酸的数目会随之增加。但是一旦氨基酸的替代率和核苷酸的替代率超过上述数字,则两个参数构建的树在拓扑长度上是不等价的。经分析,若进化距离大致上与进化时间成线性关系的话,则应选用进化距离。用进化距离重建的系统树事实上支持中性学说;若进化距离与进化时间显著地不存在线性关系的话,则可选用替代率,该情况表明中性学说不适用,似更倾向于新达尔文主义。 相似文献
140.