Interpreting Botanical Progress Azolla: A Review of Its Biology and Utilization Gregory M. Wagner..........................................1 Roles of Flavonoids in Symbiotic and Defense Functions in Legume Roots Helen A. Stafford.........................................27 River Dynamics as a Forest Process: Interaction between Fluvial Systems and Alluvial Forests in Large European River Plains Annik Schnitzler..........................................40 Sexual Specialization and Inbreeding Avoidance in the Evolution of Dioecy D. Carl Freeman, Jon Lovett Doust, Ali El-Keblawy, Kathleen J. Miglia, and E. Durant McArthur..............65 Instructions to Contributors.................................93 New Books Received...........................................96 Order Form Published Quarterly by The New York Botanical Garden Issued 31 March 1997
Azolla: A Review of Its Biology and Utilization GREGORY M. WAGNER Department of Zoology and Marine Biology University of Dar es Salaam P.O. Box 35064 Dar es Salaam Tanzania I. Abstract II. Introduction III. Taxonomy IV. Distribution V. Morphology VI. Physiology VII. Reproduction VIII. Environmental Factors Affecting Azolla Anabaena IX. The Utilization of Azolla Anabaena A. Azolla Anabaena as a Biofertilizer B. The Utilization of Azolla Anabaena on Rice C. The Application of Azolla Anabaena on Crops Other Than Rice D. Other Uses of Azolla Anabaena X. Concluding Remarks XI. Acknowledgment XII. Literature CitedI. Abstract The symbiosis Azolla Anabaena is outstanding due to its high productivity combined with its ability to fix nitrogen at high rates. Because of this, in recent decades, countless studies have been conducted on this association, but with insufficient synthesis and coordination. This paper, therefore, attempts to review and synthesize past and recent findings concerning the biology and utilization of Azolla in hopes that this will facilitate increased future collaborative research on this "green gold mine." It reviews the taxonomy, distribution, morphology, physiology, and reproduction of Azolla as well as new developments in its manifold uses.Because of the growing concern about conservation of the environment and the need for deploying renewable, sustainable resources; the application of Azolla as a biofertilizer on agricultural crops, in order to provide a natural source of the crucial nutrient nitrogen, can be very beneficial to the future of our planet. Besides the environmental appropriateness of the use of Azolla, for multitudes of farmers in many parts of the world who cannot afford chemical fertilizers, Azolla application can enhance their economic status, increasing yields while minimizing costs. Due to the fact that rice paddy fields form an ideal environment for Azolla, one of its most suitable applications is on rice. Besides its utilization as a biofertilizer on a variety of crops, Azolla can be used as an animal feed, a human food, a medicine, and a water purifier. It may also be used for the production of hydrogen fuel, the production of biogas, the control of weeds, the control of mosquitoes, and the reduction of ammonia volatilization which accompanies the application of chemical nitrogen fertilizer. Click Here to Go to Back to Top Roles of Flavonoids in Symbiotic and Defense Functions in Legume Roots HELEN A. STAFFORD Biology Department, Reed College Portland, Oregon 97202 I. Abstract II. Introduction III. Flavonoids in Nodules IV. Arbuscular Mycorrhizal Fungal Relationships V. Model Legume Genomes VII. Structural and Regulatory Genes of Root Symbioses VIII. Conclusions IX. Literature CitedI. Abstract The roles of flavonoids in roots of legumes in the symbiotic relationships with nitrogen-fixing bacteria and arbuscular mycorrhizal fungi are compared with defense functions, using examples from three legume genera, Lotus, Medicago and Glycine. Pathways leading to proanthocyanidins and isoflavonoids are emphasized. The localization of flavonoids in nodules involved in nitrogen-fixation and in the apoplastic compartment of mycorrhizal associations is briefly described, with emphasis on the need for more information concerning their precise localization. The limitation of our knowledge about the regulatory genes of the flavonoid pathway involved in both exogenous and endogenous regulation of these complex interrelationships is emphasized. Click Here to Go to Back to Top River Dynamics As a Forest Process Interaction between fluvial systems and alluvial forests in large European river plains. ANNIK SCHNITZLER Laboratoire de Phytoécologie Faculté des Sciences Ile du Saulcy, F-57045 Metz, France Tél. (33) 03 87 31 53 31 Fax: (33) 03 87 31 53 33 I. Abstract/Résumé II. Introduction III. The Geomorphic Pattern of Big River Plains IV. Particularities of the Nutrient Cycle V. Specific Particularities A. Species Abundance and Diversity B. Community Pattern and Forest Dynamics C. The Particular Case of Riverine Ecosystems of High Dynamics Rivers VI. Conclusion VII. Literature Cited
Sexual Specialization and Inbreeding Avoidance in the Evolution of Dioecy
D. Carl Freeman Jon Lovett Doust Department of Biological Sciences Department of Biological Sciences Wayne State University University of Windsor Detroit, MI 48202, U.S.A. Windsor, Ontario, Canada N9B 3P4 Ali El-Keblawy Kathleen J. Miglia Department of Biology Department of Biological Sciences University of Suez Canal Wayne State University El-Arish, Egypt Detroit, MI 48202, U.S.A. and E. Durant McArthur Shrub Sciences Laboratory U.S. Department of Agriculture Forest Service Provo, UT 84606, U.S.A. I.Abstract II. Introduction III. Animal-Pollinated Plants A. Hermaphroditism B. Potential for Inbreeding C. Avoidance of Inbreeding D. Sexual Specialization in Hermaphrodites E. Sexual Specialization and Sexual Dimorphism F. Sexual Specialization in Resource Allocation IV. Abiotic Pollination A. Potential for Inbreeding B. Potential for Compensation and Sexual Specialization V. Pathways for the Evolution of Dioecy A. Dioecy from Gynodioecy B. Summary of Gynodioecy Pathway and Predictions C. Dioecy from Monoecy VI. Spatial Niche Segregation of the Sexes VII. Sexual Lability VIII. Case Studies of Species Showing Labile Sex Expression and Intermediate Sex Forms IX. Analysis of Patterns, and Resolution of Competing Hypotheses for the Evolution of Dioecy A. Theoretical Considerations X. Conclusion XI. Acknowledgments XII. Literature Cited