The Tree That Changed the World in One Century

Total Page:16

File Type:pdf, Size:1020Kb

The Tree That Changed the World in One Century The Tree that Changed Richard Evans Schultes the World in One Century I can assure you that on that 14th of June ( 1875)( use of their product had been made any- when Mr. Wickham arrived at Kew m a hansom where in the Eastern Hemisphere. When cab with his precious bags of seeds, not even the Columbus arrived in the West Indies, he wildest could have its imagmation contemplated noted that the natives were a result.... playing game in which rubber balls were employed, but - Sir W. T. Thiselton-Dyer the rubber for these balls came not from Kew Bulletm (1912/, p. 65 Hevea but from Castilla elastica, of the fig History is usually written in the context of family. or Yet it political, social, religious changes. As early as 1755, King John of Portugal well be written from the of view might point tried to foster a rubber industry in Belem do of the effects that plants have had on the de- Para at the mouth of the Amazon River: of mankind and civilization. velopment rubber shoes were manufactured for export It is safe to that no of say smgle species to Portugal, but the quality was so poor that in the short of 100 so plant has, space years, the industry did not prosper. The process of utterly altered lifestyles around the globe as vulcanization, which has made rubber the Hevea a member of the brasihensis, spurge useful product that it is now, had not yet family, which today is the source of 98 per- been discovered. cent of the world’s natural rubber. Stop for a After Goodyear discovered vulcanization and to life without moment try imagine in the 1830s, rubber became a product with rubber! ever-increasing uses in the industrializing The introduction of this Amazonian tree nations, and demand for it increased at a ver- from the wild and its domestication in the tiginous rate. The only source was the wild 19th century was the work of the British bo- stands of Hevea - especially H. brasiliensis the Botanic - tamcal gardens, especially Royal hidden away in the dark corners of the Gardens at Kew, and is unquestionably the vast Amazon forests. The demand for rubber most outstanding example of the value of in Europe and the United States rapidly be- such institutions in life on earth. bettering came so great that production from forest in Rubber-yielding trees and vines grew trees rose from 31 tons in 1827 to 2607 tons no the Old World, yet, curiously, significant in 1856. This dramatic increase was accom- plished by the virtual enslavement of whole tribes of Indians. Tapping the trees in the A group of rubber tappers bringing m therr daily jungles for four or five months a year, away harvest of latex from forest trees m the Amazo- from their agricultural lands and sources of man region of Colombia. R. E. Schultes photo. 4 Natural distribution of Hevea andH. brasihensis. Hevea became known to the scientific community when in 1775 the French nourishment, falling prey to tropical dis- botanist J. B. C. F. Aublet described the eases and malnutrition, and often suffering genus from material collected in French from exposure, mistreatment, torture, or Guiana. He not only described the genus and even assassination if they did not bring in its first species, H. guianensis, but detailed enough rubber, they were being extermi- the native method of exploiting it for rubber nated by this forest industry, directed and appended numerous ethnobotanical data primarily by unscrupulous "rubber-barons" on the use of the seeds by the natives as food. who resided in the cities of Manaos and Twenty-six years later, K. L. Willdenow, a Iquitos, usually in sumptuous luxury. German botanist, described a second The modern age of rubber had its begin- species, H. brasiliensis, from material col- nings in 1876, a "rubber revolution" that lected at the mouth of the Amazon River. was the consequence of an incredible series Subsequent botanical exploration of the of sometimes fortuitous events. Amazon Valley - notably that carried out 5 by the British botanist Richard Spruce - forest circuit, then return to his shack and continued to add new species to the genus, begin the long process of coagulating the which now comprises 10 species and three latex. Large balls of rubber were formed by varieties. pouring the latex little by little over a pole that was rotated in smoke from an in- Not all of the species yield a latex capable rising of producing rubber: only H. guianensis, verted funnel. H. benthamiana, andH. brasihensis have The death knell for this primitive industry sufficient caoutchouc to give a usable rub- was sounded when the era of scientifically ber ; and of these, H. brasiliensis supplies the managed plantation practices began in 1876, best product. the year that rubber seeds were first germi- nated successfully in the Royal Botanic Gar- When m 1823 a Scot, Charles Macintosh, dens at Kew. The domestication of the rub- discovered that rubber would dissolve in ber tree served civilization in two ways. naphtha, it acquired many new uses, leading First, it provided an abundance of high to the establishment of factories in England, qual- rubber at low without which France, and the United States. These fac- ity cost, many of our advances in tories failed, however, because the product great industry, medicine, domestic and still became sticky in the heat and brittle in appliances, transportation the cold. would have been impossible. Second, when plantations finally came into full production This was overcome in 1839 when problem in the second decade of the 1900s, the forest a Bostonian, Charles Goodyear, discovered industry was all but obliterated, with the re- vulcanization, a process that greatly altered sult that thousands of native tappers were the of rubber and physical properties liberated from the intolerable and inhuman changed the history of the significance of exploitation to which they had been sub- this vegetal product and its effect on human jected for nearly 100 years. And, undoubt- life. It led to new and hitherto immediately - edly, whole tribes e.g., the Witotos of the unexpected applications and a host of new northwestern Amazon, a truly noble race of industries. It also the "rubber sparked Indians - were saved from virtual extinc- boom" of the then the source Amazon, only tion. of natural rubber: from the South production Domestication of the rubber tree occurred American forests rapidly increased. at the time the British were seeking new of wild rubber is a difficult Exploitation crops for their tropical colonies. The intro- and The frustratmg operation. natives, living duction of the quinine-bark tree into India the season under such abom- during tapping from the Andes had just been highly success- inable conditions, produced a poor-quality ful. Sir Clements Markham, who had di- The latex was laden product. frequently rected the introduction of that tree, was with bark, dirt, and stones and adulterated convinced that the rubber tree could be de- with other since often the rubbers, tappers veloped as a plantation crop that would be a were if did not punished they procure stipu- good substitute for the coffee crop, which a lated quotas. Furthermore, each individual fungal disease had almost exterminated in had to labor from dawn or until predawn Asia. He had Mr. James Collins prepare a noon to 100 or fewer trees in his nearly tap summary of what was then known about 6 Parts of Hevea brasiliensis, the rubber tree. the Amazon, and he fully supported Mark- ham’s view concerning the future of Hevea rubber. Collins wrote: "In 1870, I came to cultivation. the conclusion that it was necessary to do Several earlier attempts had been made to for the caoutchouc-producing tree what had introduce Hevea seed from Brazil, in 1873 already been done with such happy results and 1875. None were successful. Hevea for the cinchona (quinine) tree." Sir Joseph seed, its latex rich in sugars, quickly fer- Hooker, director of Kew Gardens, knew of ments in the heat of the tropics, and the em- Spruce’s discoveries and studies of Hevea in bryo is killed. But success eventually came. 7 Seeds ofHevea brasiliensis. R. E. Schultes photo. transport, Wickham resolved somehow to surmount this difficulty. Then a fortuitous An Englishman, Henry Wickham, who event happened! In 1876 a steamboat from had spent many years living near the Ama- England had sailed up the Amazon laden zon and Orinoco and who in 18 72 had pub- with cargo; it found no return load. "I de- lished a book on his travels in tropical South termined," Wickham wrote, "to plunge for America, had previously sent seeds of Hevea it. I had no cash on hand. The seed was even to Kew with no success. Fully realizing that then beginning to ripen. I knew that Capt. earlier shipments had failed because of slow Murry must be in a fix, so I wrote chartering 8 9 the ship." Wickham sent out his Indians to collect the seed and pack it properly m wicker baskets. The ship raced downstream from Santarem, 400 miles up the Amazon, and called in at customs in Belem at the river’s mouth. Customs officials, told of the delicacy of the plants "for delivery to Her Britannic Majesty’s own Royal Botanic Gar- dens of Kew," immediately, and with intel- ligence unusual among bureaucratic officials, dispatched the ship, which steamed off to England. All of the earlier shipments had been sent on sailing vessels. The few days saved by using a steamboat ensured successful ger- mination in Kew’s hothouses.
Recommended publications
  • Well-Known Plants in Each Angiosperm Order
    Well-known plants in each angiosperm order This list is generally from least evolved (most ancient) to most evolved (most modern). (I’m not sure if this applies for Eudicots; I’m listing them in the same order as APG II.) The first few plants are mostly primitive pond and aquarium plants. Next is Illicium (anise tree) from Austrobaileyales, then the magnoliids (Canellales thru Piperales), then monocots (Acorales through Zingiberales), and finally eudicots (Buxales through Dipsacales). The plants before the eudicots in this list are considered basal angiosperms. This list focuses only on angiosperms and does not look at earlier plants such as mosses, ferns, and conifers. Basal angiosperms – mostly aquatic plants Unplaced in order, placed in Amborellaceae family • Amborella trichopoda – one of the most ancient flowering plants Unplaced in order, placed in Nymphaeaceae family • Water lily • Cabomba (fanwort) • Brasenia (watershield) Ceratophyllales • Hornwort Austrobaileyales • Illicium (anise tree, star anise) Basal angiosperms - magnoliids Canellales • Drimys (winter's bark) • Tasmanian pepper Laurales • Bay laurel • Cinnamon • Avocado • Sassafras • Camphor tree • Calycanthus (sweetshrub, spicebush) • Lindera (spicebush, Benjamin bush) Magnoliales • Custard-apple • Pawpaw • guanábana (soursop) • Sugar-apple or sweetsop • Cherimoya • Magnolia • Tuliptree • Michelia • Nutmeg • Clove Piperales • Black pepper • Kava • Lizard’s tail • Aristolochia (birthwort, pipevine, Dutchman's pipe) • Asarum (wild ginger) Basal angiosperms - monocots Acorales
    [Show full text]
  • DECOMPOSITION of the RUBBER TREE Hevea Brasiliensis LITTER at TWO DEPTHS
    RESEARCH DECOMPOSITION OF THE RUBBER TREE Hevea brasiliensis LITTER AT TWO DEPTHS Thiago Claudino Gréggio1 , Luiz Carlos Assis1, and Ely Nahas1* A B S T R A C T INTRODUCTION The decomposition of soil litter contributes to Maintenance of a forest ecosystem depends on the soil maintaining agricultural sustainability, since the physical-chemical properties and its interaction with nutrients released by microbial activity are the biotic communities that act, on different temporal determinants of the net productivity of the and spatial scales, in cycling of organic material (OM), agroecosystem. The decomposition of rubber tree consequently providing the nutrients necessary for this (Hevea brasiliensis [Willd. ex A. Juss.] Müll. Arg.) system (Beare et al., 1995). The greater source of leaves located on the surface and buried in at 10 cm residues comes from the OM decomposition of leaf depth in Forest and Savannah (Cerradão) soils litter that is accumulated on the surface of the soil, (Oxisols) was studied, with emphasis on the and the dead roots of the plants (Chadwick et al., 1998; production of CO2 and the monthly variation of the Fioretto et al., 2001; Santa Regina and Tarazona, remaining amounts of litter mass, soluble substances, 2001). cellulose and lignin. To evaluate CO2 production, H. brasiliensis leaves were incubated for 30 days in soils Among the decomposing agents, bacteria and fungus from the 0-2 cm and 10-12 cm layers. CO2 production have a preponderant role due to their greater biomass increased in the 0-2 cm layer in comparison to the 10- and respiratory metabolism (Torres et al., 2005).
    [Show full text]
  • In Search of the Amazon: Brazil, the United States, and the Nature of A
    IN SEARCH OF THE AMAZON AMERICAN ENCOUNTERS/GLOBAL INTERACTIONS A series edited by Gilbert M. Joseph and Emily S. Rosenberg This series aims to stimulate critical perspectives and fresh interpretive frameworks for scholarship on the history of the imposing global pres- ence of the United States. Its primary concerns include the deployment and contestation of power, the construction and deconstruction of cul- tural and political borders, the fluid meanings of intercultural encoun- ters, and the complex interplay between the global and the local. American Encounters seeks to strengthen dialogue and collaboration between histo- rians of U.S. international relations and area studies specialists. The series encourages scholarship based on multiarchival historical research. At the same time, it supports a recognition of the represen- tational character of all stories about the past and promotes critical in- quiry into issues of subjectivity and narrative. In the process, American Encounters strives to understand the context in which meanings related to nations, cultures, and political economy are continually produced, chal- lenged, and reshaped. IN SEARCH OF THE AMAzon BRAZIL, THE UNITED STATES, AND THE NATURE OF A REGION SETH GARFIELD Duke University Press Durham and London 2013 © 2013 Duke University Press All rights reserved Printed in the United States of America on acid- free paper ♾ Designed by Heather Hensley Typeset in Scala by Tseng Information Systems, Inc. Library of Congress Cataloging-in - Publication Data Garfield, Seth. In search of the Amazon : Brazil, the United States, and the nature of a region / Seth Garfield. pages cm—(American encounters/global interactions) Includes bibliographical references and index.
    [Show full text]
  • Fecal Metagenomics for the Simultaneous Assessment of Diet
    Srivathsan et al. Frontiers in Zoology (2016) 13:17 DOI 10.1186/s12983-016-0150-4 RESEARCH Open Access Fecal metagenomics for the simultaneous assessment of diet, parasites, and population genetics of an understudied primate Amrita Srivathsan1,2,3*, Andie Ang4, Alfried P. Vogler2,3 and Rudolf Meier1,5 Abstract Background: Rapid habitat loss and degradation are responsible for population decline in a growing number of species. Understanding the natural history of these species is important for designing conservation strategies, such as habitat enhancements or ex-situ conservation. The acquisition of observational data may be difficult for rare and declining species, but metagenomics and metabarcoding can provide novel kinds of information. Here we use these methods for analysing fecal samples from an endangered population of a colobine primate, the banded leaf monkey (Presbytis femoralis). Results: We conducted metagenomics via shotgun sequencing on six fecal samples obtained from a remnant population of P. femoralis in a species-rich rainforest patch in Singapore. Shotgun sequencing and identification against a plant barcode reference database reveals a broad dietary profile consisting of at least 53 plant species from 33 families. The diet includes exotic plant species and is broadly consistent with > 2 years of observational data. Metagenomics identified 15 of the 24 plant genera for which there is observational data, but also revealed at least 36 additional species. DNA traces for the diet species were recovered and identifiable in the feces despite long digestion times and a large number of potential food plants within the rainforest habitat (>700 species). We also demonstrate that metagenomics provides greater taxonomic resolution of food plant species by utilizing multiple genetic markers as compared to single-marker metabarcoding.
    [Show full text]
  • Henry Wickham
    SIR HENRY ALEXANDER WICKHAM 1846-1928 Ref. 24 Sir Henry was an explorer and adventurer Born into a middle class family, Henry was who travelled to Nicaragua, Latin America and the eldest son of a solicitor, also Henry, who many another wild lands. He was born on died four years after his birth in the London Friday 29 May 1846 at Haverstock Hill, Cholera epidemic of 1850, leaving Henry and Hampstead, North London, and is buried in his siblings to be raised by his mother, Harriet, Wickham, having held a life-long conviction who followed the millinery trade to support the that his family were the direct descendents of family. William of Wykeham. Henry was born into the age of the adventurer explorer, who considered himself “the instrument of his Maker”, and an atmosphere in which the goals of the British Empire were to civilise the World through the spread of Christianity and free trade. It was also the high point of the Industrial Revolution, where industry flourished by virtue of three basic commodities – steel to make machines, coal to raise the steam to power them, and rubber to provide seals and gaskets, hoses and belts and, in the fullness of time, tyres for the emerging motor car industry. continued ... 1 Henry was an outdoor, roaming sort of lad but no great scholar, so the life of an adventurer suited his temperament admirably. Inspired by contemporary accounts from adventurers and explorers, and in the hope of regaining some fortune for his family, in 1866, aged 20, he travelled to Nicaragua, arriving on 22nd October in the schooner “ Jonathan ”.
    [Show full text]
  • How the Olmec Used Bitumen in Ancient Mesoamerica
    Journal of Anthropological Archaeology 27 (2008) 175–191 Contents lists available at ScienceDirect Journal of Anthropological Archaeology journal homepage: www.elsevier.com/locate/jaa How the Olmec used bitumen in ancient Mesoamerica Carl J. Wendt a,*, Ann Cyphers b a Department of Anthropology, California State University, 800 N State College Boulevard, Fullerton, P.O. Box 6846, Fullerton, CA 92834-6846, USA b Instituto de Investigaciones Antropológicas, Universidad Nacional Autónoma de México, Circuito Exterior C.U., Delegación Coyoacan, México D.F. 04510, Mexico article info abstract Article history: Bitumen, found in abundance in Mesoamerica’s southern Gulf Coast region in natural seeps and in many Received 11 May 2007 archeological contexts, is an important economic resource and exchange item that has received little con- Revision received 18 February 2008 sideration in Mesoamerica. Analyses of archeological, ethnoarcheological, and experimental data provide Available online 9 May 2008 insights on the organization of bitumen processing activities, and the end product (archeological bitu- men), which the Olmec (1200–400 BC) used in the production of many items. Archeological data are Keywords: derived from investigations at El Remolino and Paso los Ortices— two Early Formative period levee sites Olmec in the San Lorenzo Olmec region. Our findings suggest that among the Olmec, bitumen processing was Bitumen organized as a specialized activity, involving multiple production stages, but not necessarily elite involve- Chapopote Asphaltum
    [Show full text]
  • Biogeochemical Relationships of a Subtropical Dry Forest on Karst
    2017 CARIBBEANCaribbean Naturalist NATURALIST No. 41:1–24No. 41 E. Medina, E. Cuevas, H. Marcano-Vega, E. Meléndez-Ackerman, and E.H. Helmer Biogeochemical Relationships of a Subtropical Dry Forest on Karst Ernesto Medina1,2,*, Elvira Cuevas3, Humfredo Marcano-Vega4, Elvia Meléndez-Ackerman3, and Eileen H. Helmer1 Abstract - Tropical dry forests on calcareous substrate constitute the main vegetation cover in many islands of the Caribbean. Dry climate and nutrient scarcity in those environments are ideal to investigate the potential role of high levels of soil calcium (Ca) in regulating plant selection and productivity. We analyzed the elemental composition of soil, loose lit- ter, and leaf samples of the woody vegetation on the plateau of Mona Island, an emergent block of carbonate rock in the Caribbean located between Puerto Rico and the Dominican Republic, to explore the nutrient relationships of plants growing on calcareous substrates. The mineral soil has an elemental composition characterized by high levels of aluminum (Al) and iron (Fe) in agreement with the hypothesis that it derives in part from sediments transported by rivers eroding plutonic rocks, and deposited before the massive lifting of biological limestone. Calcium concentration varied within sites, and Ca–Al and Ca–Fe cor- relations were negative in soils and positive in plant material, implying that element uptake from these soils depends on acidification of the rhizosphere. This acidification should be high enough to extract carbonate-bound elements and solubilize Al, Fe, and probably phos- phate (P) compounds. The most abundant cation in leaves was Ca, followed by potassium (K) and magnesium (Mg); Ca/K and Ca/Mg molar ratios averaged 2 and 3, respectively, in- dicating that most species maintain K and Mg uptake in the presence of high Ca levels.
    [Show full text]
  • Natural Rubber Systems and Climate Change Proceedings and Extended Abstracts from the Online Workshop, 23–25 June 2020
    May 2021 FTA WORKING PAPER • 9 Natural rubber systems and climate change Proceedings and extended abstracts from the online workshop, 23–25 June 2020 Salvatore Pinizzotto, Datuk Dr Abdul Aziz b S A Kadir, Vincent Gitz, Jérôme Sainte-Beuve, Lekshmi Nair, Eric Gohet, Eric Penot, Alexandre Meybeck Natural rubber systems and climate change Proceedings and extended abstracts from the online workshop, 23–25 June 2020 The CGIAR Research Program on Forests, Trees and Agroforestry (FTA) Working Paper 9 © 2021 The CGIAR Research Program on Forests, Trees and Agroforestry (FTA) Content in this publication is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0), http://creativecommons.org/licenses/by/4.0/ DOI: 10.17528/cifor/008029 Pinizzotto S, Aziz A, Gitz V, Sainte-Beuve J, Nair L, Gohet E, Penot E and Meybeck A. 2021. Natural rubber systems and climate change: Proceedings and extended abstracts from the online workshop, 23–25 June 2020. Working Paper 9. Bogor, Indonesia: The CGIAR Research Program on Forests, Trees and Agroforestry (FTA). CGIAR Research Program on Forests, Trees and Agroforestry CIFOR Headquarters Jalan CIFOR Situ Gede, Sindang Barang Bogor Barat 16115 Indonesia T +62-251-8622-622 E [email protected] foreststreesagroforestry.org We would like to thank all funding partners who supported this research through their contributions to the CGIAR Fund. For a full list of the ‘CGIAR Fund’ funding partners please see: http://www.cgiar.org/our-funders/ Any views expressed in this publication are those of the authors. They do not necessarily represent the views of The CGIAR Research Program on Forests, Trees and Agroforestry (FTA), the editors, the authors’ institutions, the financial sponsors or the reviewers.
    [Show full text]
  • Species Composition, Diversity and Structure of Novel Forests of Castilla Elastica in Puerto Rico
    Tropical Ecology 55(2): 231-244, 2014 ISSN 0564-3295 © International Society for Tropical Ecology www.tropecol.com Species composition, diversity and structure of novel forests of Castilla elastica in Puerto Rico JÉSSICA FONSECA DA SILVA1,2 1International Institute of Tropical Forestry, USDA Forest Service, 1201 Calle Ceiba, Jardín Botánico Sur, Río Piedras, Puerto Rico, 00926-1119 2Crest-Center for Applied Tropical Ecology, University of Puerto Rico, Facundo Bueso Building, Office 301 - A, San Juan, Puerto Rico, 00931 Abstract: Attributes of novel forests (secondary forests containing introduced species) were compared with those of native secondary forests of similar age. The study area was the biological reserve called El Tallonal, in Puerto Rico. Species composition, tree density, basal area and soil bulk density were characterized; Importance value index (IVI), Shannon’s diversity index (H’) and total aboveground biomass (TAGB) were calculated for stands of novel forests for Castilla elastica, an introduced naturalized tree. The IVI of C. elastica was 37 percent; that for Guarea guidonia, a native species, was 14 percent. Compared to native secondary forests, C. elastica forests had similar species richness (27 species in an area of 0.3 ha), low diversity (H’ = 0.63) and tree density (1039 trees ha-1), moderate basal area (42 m2 ha-1) and TAGB (216 Mg ha-1), and low soil bulk density (0.5 to 0.7 g cm-3). The structural features of novel forests of C. elastica are in the normal range of variation for those of native secondary forests in the tropics. Resumen: Los atributos de bosques novedosos (bosques secundarios que contienen especies introducidas) fueron comparados con los de bosques secundarios de edad similar.
    [Show full text]
  • Evaluating the Development and Potential Ecological Impact of Genetically Engineered Taraxacum Kok-Saghyz
    Evaluating the Development and Potential Ecological Impact of Genetically Engineered Taraxacum kok-saghyz DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Brian J. Iaffaldano Graduate Program in Horticulture and Crop Science The Ohio State University 2016 Dissertation Committee: Professor Katrina Cornish, Advisor Professor John Cardina Professor David Francis Professor Allison Snow Copyrighted by Brian J. Iaffaldano 2016 Abstract Natural rubber is a biopolymer with irreplaceable properties, necessary in tires, medical devices and many other applications. Nearly all natural rubber production is dependent on a single species, Hevea brasiliensis. Hevea has several disadvantages, including a long life cycle, epidemic diseases, and rising production costs which have led to interest in developing new sources of rubber with similar quality to Hevea. One species that meets this criterion is Taraxacum kok-saghyz (TK), a widely adapted species of dandelion that can produce substantial amounts of rubber in its roots in an annual growing period. Shortcomings of TK include an inability to compete with many weeds, resulting in poor establishment and yields. In addition, there is variability in the amount of rubber produced, plant vigor, and seed establishment. In order to address these shortcomings, genetic engineering or breeding may be used to introduce herbicide resistance and allocate more resources to rubber production. We have demonstrated stable transformation in Taraxacum species using Agrobacterium rhizogenes to introduce genes of interest as well has hairy root phenotypes. Inoculated roots were subjected to selection by kanamycin and glufosinate and allowed to regenerate into plantlets without any hormonal treatments or additional manipulations.
    [Show full text]
  • El Cultivo Del Hule En México
    Libros Técnicos: Serie Forestal Programa Forestal Colegio de Postgraduados EL CULTIVO DEL HULE EN MÉXICO Gustavo E. Rojo Martínez Rosa Martínez Ruiz Jesús Jasso Mata M. en C. José Concepción Castro Robles Rector Lic. Ismael Gámez Robles Secretario General Lic. Marco Antonio Flores Flores Coordinador General Educativo Lic. Carlos Ernesto Villa Panquián Coordinador General Administrativo Dr. Ernesto Guerra García Coordinador de Investigación Lic. Juan Antonio Delgado Morales Coordinador Unidad Mochicahui Lic. Rosario Rochín Napus Coordinador Unidad Los Mochis Lic. María de Lourdes Osuna Moreno Abogada General Ma. Lourdes Burgos Zazueta Vinculación y Extensión Universitaria Libros Técnicos: Serie Forestal El cultivo del Hule en México 1ª edición, México, 2011. D.R. © Gustavo E. Rojo Martínez Rosa Martínez Ruiz Jesús Jasso Mata Diseño de portada: Gustavo E. Rojo Martínez. Apoyo: Elvia N. Rodríguez Sauceda. ISBN: 968-899-345-1 Impreso y hecho en México Printed and made in Mexico Publicado por: Universidad Autónoma Indígena de México Benito Juárez # 39, C. P. 81890 Tels. (698) 89 2 00 42 Ext. 120. Mochicahui, El Fuerte, Sinaloa. www.uaim.edu.mx Colegio de Postgraduados. Campus Montecillo Programa de Forestal Km. 36.5 Carr. Fed. México-Texcoco, Montecillo, Edo. de México Tel.: 01 595 95 2 02 00 Ext. 1887. Tel. Directo 58 04 59 88 Ext. 1887 Fax.: 58 04 59 88 Ext. 1850. Este libro no puede ser fotocopiado ni reproducido total o parcialmente por ningún otro medio o método sin la autorización por escrito de los editores. Libros Técnicos: Serie Forestal
    [Show full text]
  • X-Ray Diffraction Patterns of Hevea, Manihot, and Other Rubbers
    U. S. DEPARTMENT OF COMMERCE NATIONAL B UREAU OF STANDARDS RESEARCH PAPER RP1218 Part of Journal of Research of the National Bureau of Standards, Volume 23, July 1939 X.RAY DIFFRACTION PATTERNS OF HEVEA, MANIHOT, AND OTHER RUBBERS By George L. Clark. 1 Siegfried T. Gross.2 and W. Harold Smith ABSTRACT When rubber from Hevea brasiliensis is stretched quickly and exposed to a beam of X-rays, a crystal fiber diffraction pattern is obtained. During previous work, done jointly by the National Bureau of Standards and the University of Illinois on sol and gel fractions of this rubber, no pattern was produced by the stretched sol fraction. With the stretched gel fraction, however, the pattern was sharp and intense. Rubber from Manihot glaziovii also may be separated into sol and gel fractions, and in recent work they, too, have been stretched and examined by X-rays. With the stretched Manihot sol, a few interferences were obtained, but many more resulted with the stretched gel. When crystallized by "freezing" at low t empera­ tures for 24 hours, the interferences from the gel again outnumbered those from the sol. The X-ray measurements of Manihot rubber agree with those of Hevea rubber and indicate that the same structure exists in each. Rubbers obtained from latices of Funtumia elastica, Cryptostegia grandijiora, and Castilla elastica were also examined. Their structures, too, were like that of Hevea rubber, and the similarity confirms earlier observations made when X-ray technique was less highly developed. In crystallized specimens, the crystals melted within the range of temperatures previously observed with Hevea rubber.
    [Show full text]