• Agave Adaptation to Aridity

      Burgess, Tony L.; Herbarium, University of Arizona (University of Arizona (Tucson, AZ), 1985)
      To show features of Agave taxa adapting to arid habitats, comparative studies at three taxonomic levels in the genus are presented. There is a brief review of Agave physiology and some aspects of recent evolution are discussed. Comparisons among species groups within the genus show several traits differentiating desert species from related taxa. Related taxa in the Deserticolae group are examined over a transect in Baja California, revealing patterns linking leaf shape to climate. In a comparison of leaves of A. desert] Engelm. along an elevational gradient, high intrapopulation variation obscures differences between the sites. Results are summarized as hypotheses to be tested.
    • Agave and the Pre-Cortés Religion of the Mexican Altiplano Centrál

      Crosswhite, F. S. (University of Arizona (Tucson, AZ), 1985)
    • Agave Research Progress in Yucatan

      Cruz-Ramos, Carlos A.; Orellana, Roger; Robert, Manuel L.; Centro de Investigacion Cientifica de Yucatán (University of Arizona (Tucson, AZ), 1985)
      The Center for Scientific Research of Yucatan carries out research aimed at solving some of the problems posed by the henequen industry in northern Yucatan. This paper briefly describes CICY's main research lines related to the hard fiber-producing agaves: a) taxonomic studies are being pursued to obtain a better understanding of the flora of the region; b) tissue culture techniques are used for the genetic improvement of agaves, and c) studies of composite materials and chemical substances derived from Henequen wastes are being carried out as possible alternatives to cordage production.
    • Aspects of the Reproductive Biology of Agave lechuguilla Torr.

      Freeman, C. Edward; Reid, William H.; Department of Biological Sciences, University of Texas at El Paso (University of Arizona (Tucson, AZ), 1985)
      Agave lechuguilla Torr. is a small, widespread century plant characteristic of the Chihuahuan Desert growing from central Mexico to southern New Mexico. Most reproduction is vegetative. Flowering occurs primarily in May and June. The inflorescence shaft grows as rapidly as 2 dm/day, and reaches full height (about 2.6 m) in three to four weeks. Energy for flowering is stored almost entirely in the leaves. Flowers open in late afternoon, and last for approximately 96 hours. Anthers dehisce 24 hours after a flower opens and the stigma becomes receptive at approximately 66 hours. Nectar is produced during the second and third nights. The anatomy of the flower is of interest in that the pollen tubes do not penetrate tissue but have an unobstructed path to the ovules. The species is capable of self-pollination, but not apomixis.
    • The Bat, the Blossom and the Biologist

      Howell, Donna J.; Far Flung Adventures (University of Arizona (Tucson, AZ), 1985)
    • Chromosome and Hybridization Studies of Agave

      Pinkava, Donald J.; Baker, Mark A.; Department of Botany and Microbiology, Arizona State University (University of Arizona (Tucson, AZ), 1985)
      Interspecific hybridization, paleopolyploidy, secondary polyploidy, and vegetative reproduction appear to play significant roles in the evolution of Agave and certain related genera. First chromosome counts are reported for Hesperaloe funifera and 10 taxa of Agave including two triploid and one diploid putative hybrids. All of our counts for Yucca, Hesperaloe, and Agave are in agreement with the base number, x = 30, which comprises a complement of five very large chromosomes and 25 medium to small chromosomes. All published chromosome counts of Agave have been tabulated and the roles of hybridization and polyploidy are assessed. Secondary polyploidy occurs in 26 of 48 (54.2 %) reported taxa of Agave; as yet only one-fourth of the total taxa are chromosomally known.
    • Conservation of Southwestern Agaves

      Reichenbacher, Frank W.; F. W. Reichenbacher & Associates (University of Arizona (Tucson, AZ), 1985)
      The status of Southwestern agaves being considered for listing under the 1973 Endangered Species Act are summarized. Numerous Mexican agaves appear to merit consideration for listing as threatened or endangered species. An outline of action to accomplish this and achieve some much-needed communication between the United States and Mexico is presented. The agaves are clearly of Mexican origin. Species abundance contour maps are used to locate areas and species of special significance in the study of the evolution of the genus and to map out a conservation plan for the genus.
    • A Demographic Study of Maguey Verde (Agave salmiana ssp. Crassispina) Under Conditions of Intense Utilization

      Martinez-Morales, Rafael; Meyer, Susan E.; Centro Regional para Estudios de Zonas Acidas y Semiaridas del Colegio de Postgraduasos Salinas de Hidalgo, San Luis Potosí, México (University of Arizona (Tucson, AZ), 1985)
      In western San Luis Potosi, Mexico, wild populations of Maguey Verde (Agave Salmiana Otto ex Salm-Dyck ssp. crassispina (Trel.) Gentry) are intensively utilized, especially as raw material for production of the distilled liquor mezcal. A demographic approach was used to investigate possible explanations for recent population decline. The effect of overgrazing on the survival of young plants (offsets) was found to be a major problem. Harvest of sexually mature plants for mezcal aggravates the problem by leaving both soil and offsets exposed. But, in itself, this harvest seems to constitute a reasonable long-term use for wild populations, even though seed production is halted.
    • Desert Plants, Volume 7, Number 2 (1985)

      Unknown author (University of Arizona (Tucson, AZ), 1985)
    • Field Evaluations of Agave in Arizona

      McDaniel, Robert G.; Department of Plant Sciences, University of Arizona (University of Arizona (Tucson, AZ), 1985)
      Four agave species (Agave americana L., A. murpheyi E Gibson, A. palmeri Engelm., and A. parryi Engelm.) have been evaluated in a four-year study conducted at four Arizona field locations. Survival data, growth rates, approximate water requirements, and insect predation have been analyzed under Arizona field conditions. All species showed good survival at the Marana location, with Agave americana exhibiting the most rapid growth increment, averaging fresh weight gains of 70 to 110 kg per plant in the four-year period, with minimal supplemental irrigation. Analysis of carbohydrates in these plants showed an average 50% sugars on a dry weight basis. Projected growth parameters and biomass accumulation data are presented.
    • Introduction to the Symposium

      Gentry, Howard Scott; Desert Botanical Garden (University of Arizona (Tucson, AZ), 1985)
    • The Mezcal Industry in the Altiplano Potosino-Zacatecano of North-Central Mexico

      Tello-Balderas, J. Jesús; Garcia-Moya, Edmundo; Centro Regional para Estudios de Zonas Acidas y Semiaridas del Colegio de Postgraduasos Salinas de Hidalgo, San Luis Potosí, México (University of Arizona (Tucson, AZ), 1985)
      Agaves play an important role both ecologically and economically in the San Luis Potosi-Zacatecas region. This study describes the principal use of one of the wild species, the manufacture of the distilled liquor mezcal. The resource is currently overexploited, resulting in dwindling supplies of raw material. This is in turn sub-utilized, since harvest practices are not carried out in an organized manner and the technology used in mezcal manufacture is antiquated and inefficient.
    • Prehistoric Cultivation in Southern Arizona

      Fish, Suzanne K.; Fish, Paul R.; Miksicek, Charles; Madsen, John; Arizona State Museum; Office of Arid Lands Studies, University of Arizona (University of Arizona (Tucson, AZ), 1985)
      Gathering of wild agave for food and fiber is widely recognized in ethnographic accounts of Southwestern Indians. Historically documented cultivation is limited to small-scale plantings and has not established agave as a significant aboriginal cultigen. The apparent absence of agave as a cultivated staple among peoples of the Sonoran Desert contrasts with pre-Columbian and historic ubiquity of this crop further south. It is a major cultigen throughout the rest of highland Mexico, including areas in Durango and Zacatecas, often considered within the greater Southwestern cultural sphere. Current archaeological evidence suggests that agave figured more prominently in prehistoric Southwestern agriculture than in that of subsequent groups.
    • The Tequila Industry in Jalisco, Mexico

      Valenzuela-Zapata, Ana Guadalupe; Facultad de Agricultura, Universidad de Guadalajara (University of Arizona (Tucson, AZ), 1985)
      In Jalisco, several liquors are extracted from plants of the genus Agave L. Tequila is the most important of these, because of its large national and international market. It is a major Mexican export product. In order to produce the various tequilas, the juices of Agave tequilana Weber are fermented, distilled, and prepared in various forms. The principal plantations are located between 20°30' and 21° north latitude and 102°30' and 104° west longitude and cover 16,000 hectares of dry-farmed lands with a warm temperate, semi-arid climatic regime. Over 50% of the factories are located in the Tequila region of Jalisco; these account for 80% of the world production.
    • Water Relations and Carbon Dioxide Uptake of Agave deserti - Special Adaptations to Desert Climates

      Nobel, Park S.; Department of Biology, University of California at Los Angeles; Laboratory of Biomedical and Environmental Sciences, University of California at Los Angeles (University of Arizona (Tucson, AZ), 1985)
      Agave deserti Engelm., a common agave of the Sonoran Desert, possesses Crassulacean acid metabolism. Thus, the main period for stomatal opening and net CO, uptake is at night, which leads to a high water -use efficiency. Seedling establishment occurs only when enough water -storage capacity can be generated following germination so that the young seedling can withstand the first drought. Agave deserti is only moderately tolerant of low tissue temperatures but extremely tolerant of high tissue temperatures, an important desert adaptation. Its rosette growth habit leads to a relatively uniform distribution of photosynthetically active radiation over the leaves, which contributes to its high productivity for a desert plant.