Associative and Endophytic Nitrogen-fixing Bacteria and Cyanobacterial Associations This book is part of the seven-volume series that was launched a few years ago with the ambitious objectives of reviewing the field of nitrogen fixation from its earliest beginnings through the millennium change and of consolidating the relevant information - from fundamental to agricultural and environmental aspects – all in one place. Volume 5 covers the biology of bacteria that associate with n- leguminous plants. The subject matter includes a wide range of associations; it covers the bacterial species that associate either with the surface or within the tissues of grasses (often referred as plant growth-promoting rhizobacteria) and also the symbiotic associations that cyanobacteria form with fungi, algae, and both lower and higher plants. This volume does not deal with the Frankia-actinorhizal plant associations, which is the topic of Volume 6. The book is divided in 13 chapters, each of which is the work of well-known scientists in the field. Just like in the other volumes of this series, the first chapter is th an historical perspective. It describes how, as early as the end of the 19 century, it was shown that plant exudation favoured the proliferation of soil bacteria in the rhizosphere, and how the first nitrogen-fixing bacteria, including cyanobacteria were isolated. The chapter covers the landmarks and scientific concepts that arose from more than one century of research in this area.
This book is the self-contained fifth volume of a comprehensive seven-volume series covering both fundamental and applied aspects of nitrogen-fixation research since the 19th century. It addresses the issues arising from bacterial colonization of either the plant-root surface or other tissues as well as their modes of doing so. These associations are less formalized than the rhizobia-legume symbiosis but, as more and more of them are discovered, their myriad of effects on their plant hosts is becoming understood. Among the effects, in addition to often providing fixed nitrogen, plant growth can be promoted and plant diseases controlled. An understanding at the molecular level of the mechanisms by which these bacteria benefit crop productivity is an important issue in agriculture.This book describes the milestones in the discovery of the associative and endophytic nitrogen-fixing bacteria (Azoarcus, Azospirillum, Gluconacetobacter, Herbaspirillum, and others) found intimately involved with cereal crops, forage grasses, and sugar cane.
It provides a comprehensive overview of their phylogeny, physiology, and genetics as well as of the biology of their association with their host plants, including tools for in situ localization and population-dynamics analysis. There are also chapters describing the bacterial functions required for a bacterium to be competent and competitive in the rhizosphere; these include chemotactic response, adhesion and motility, enzymes and secondary-metabolite production, and synthesis of phytohormones, which play an important role in the association with the host plants. In addition, the plant's response to inoculation is reviewed.The book also provides an up-to-date analysis of the different associations of cyanobacteria with fungi, diatoms, bryophytes, cycads, Azolla, and Gunnera, including the complex regulatory network that controls the differentiation of vegetative cells into nitrogen fixing heterocysts.
No other available work provides the up-to-date and in-depth coverage of this volume, which is intended to serve as an indispensable reference work for academic, government, and industrial scientists working in the areas of plant microbiology, ecology, and genetics, including those studying plant growth and biocontrol; to assist students to enter this challenging area of research; and to provide science administrators with ready access to vital relevant information.