Author: Rathi C.R
Publisher: Amazon Publishers, USA
ISBN:
Category : Education
Languages : en
Pages :
Book Description
Mirabilis jalapa a perennial, herbaceous, bushy plant that reaches stature heights of mostly 1 meter, rarely up to 2 meters, in height. It may also be grown as an annual, especially in the temperate zone. The single-seeded fruits are spherical, wrinkled and black upon maturity, having started out greenish-yellow. The stems are thick, full, quadrangular with many ramifications and rooting at the nodes. The posture is often prostrate. A curious aspect of M. jalapa is that flowers with different colors grow simultaneously on the same plant. Additionally, an individual flower can be splashed with different colors. Flower patterns are referred to as sectors (whole sections of flower), flakes (stripes of varying length), and spots. A single flower can be plain yellow, red, magenta, pink, or white, or have a combination of sectors, flakes, and spots. Furthermore, different combinations of flowers and patterns can occur on. Artificial seeds are the living seed-like structure which are made experimentally by a technique where somatic embryoids derived from plant tissue culture are encapsulated by a hydrogel and such encapsulated embryoids behave like true seeds if grown in soil and can be used as a substitute of natural seeds. different flowers of the same plant. The viability of the artificial seeds depend on several factors related to conditions of storing the seeds and parts of the flower from which the explant is obtained. The protoplast is prepared from several parts like flower, leaf, stem, root, buds and meristem. These explants are grown in different concentrations of sucrose like 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%. The production of synthetic seeds are also studied in this experiment.
Evaluation of protoplast viability of Mirabilis jalapa and synthetic seed production
Author: Rathi C.R
Publisher: Amazon Publishers, USA
ISBN:
Category : Education
Languages : en
Pages :
Book Description
Mirabilis jalapa a perennial, herbaceous, bushy plant that reaches stature heights of mostly 1 meter, rarely up to 2 meters, in height. It may also be grown as an annual, especially in the temperate zone. The single-seeded fruits are spherical, wrinkled and black upon maturity, having started out greenish-yellow. The stems are thick, full, quadrangular with many ramifications and rooting at the nodes. The posture is often prostrate. A curious aspect of M. jalapa is that flowers with different colors grow simultaneously on the same plant. Additionally, an individual flower can be splashed with different colors. Flower patterns are referred to as sectors (whole sections of flower), flakes (stripes of varying length), and spots. A single flower can be plain yellow, red, magenta, pink, or white, or have a combination of sectors, flakes, and spots. Furthermore, different combinations of flowers and patterns can occur on. Artificial seeds are the living seed-like structure which are made experimentally by a technique where somatic embryoids derived from plant tissue culture are encapsulated by a hydrogel and such encapsulated embryoids behave like true seeds if grown in soil and can be used as a substitute of natural seeds. different flowers of the same plant. The viability of the artificial seeds depend on several factors related to conditions of storing the seeds and parts of the flower from which the explant is obtained. The protoplast is prepared from several parts like flower, leaf, stem, root, buds and meristem. These explants are grown in different concentrations of sucrose like 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%. The production of synthetic seeds are also studied in this experiment.
Publisher: Amazon Publishers, USA
ISBN:
Category : Education
Languages : en
Pages :
Book Description
Mirabilis jalapa a perennial, herbaceous, bushy plant that reaches stature heights of mostly 1 meter, rarely up to 2 meters, in height. It may also be grown as an annual, especially in the temperate zone. The single-seeded fruits are spherical, wrinkled and black upon maturity, having started out greenish-yellow. The stems are thick, full, quadrangular with many ramifications and rooting at the nodes. The posture is often prostrate. A curious aspect of M. jalapa is that flowers with different colors grow simultaneously on the same plant. Additionally, an individual flower can be splashed with different colors. Flower patterns are referred to as sectors (whole sections of flower), flakes (stripes of varying length), and spots. A single flower can be plain yellow, red, magenta, pink, or white, or have a combination of sectors, flakes, and spots. Furthermore, different combinations of flowers and patterns can occur on. Artificial seeds are the living seed-like structure which are made experimentally by a technique where somatic embryoids derived from plant tissue culture are encapsulated by a hydrogel and such encapsulated embryoids behave like true seeds if grown in soil and can be used as a substitute of natural seeds. different flowers of the same plant. The viability of the artificial seeds depend on several factors related to conditions of storing the seeds and parts of the flower from which the explant is obtained. The protoplast is prepared from several parts like flower, leaf, stem, root, buds and meristem. These explants are grown in different concentrations of sucrose like 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%. The production of synthetic seeds are also studied in this experiment.
Mirabilis jalapa as natural food dye and primary quality analysis
Author: Rathi C.R
Publisher: Amazon Publishers, USA
ISBN:
Category : Education
Languages : en
Pages :
Book Description
Synthetic food colors are widely used in different types of food stuffs in India as well as in the world. Changing lifestyles across the globe have transformed food habit patterns. The instant and processed foods (junk foods) are mainly used in a variety of attractive “Synthetic food colors” by its manufacturers. The natural food pigments were extracted from the Mirabilis jalapa flowers, and leaf of Nyctaginaceae family. The extracted natural food pigments were exposed to different pH, temperature and various quality analysis. The result showed that the different parameters express as Mirabilis jalapa pigment as high stability natural food colouring agent. In the present study also an attempt has been aimed to study the Extraction, Titrable acidity, Ascorbic acid content, Phytochemical analysis and adulteration by Chromatographic methods.
Publisher: Amazon Publishers, USA
ISBN:
Category : Education
Languages : en
Pages :
Book Description
Synthetic food colors are widely used in different types of food stuffs in India as well as in the world. Changing lifestyles across the globe have transformed food habit patterns. The instant and processed foods (junk foods) are mainly used in a variety of attractive “Synthetic food colors” by its manufacturers. The natural food pigments were extracted from the Mirabilis jalapa flowers, and leaf of Nyctaginaceae family. The extracted natural food pigments were exposed to different pH, temperature and various quality analysis. The result showed that the different parameters express as Mirabilis jalapa pigment as high stability natural food colouring agent. In the present study also an attempt has been aimed to study the Extraction, Titrable acidity, Ascorbic acid content, Phytochemical analysis and adulteration by Chromatographic methods.
Pollination Mechanisms, Reproduction and Plant Breeding
Author: R. Frankel
Publisher: Springer Science & Business Media
ISBN: 3642810594
Category : Science
Languages : en
Pages : 294
Book Description
view than its own proper males should fecundate each blossom." ANDREW KNIGHT Philosophical Transactions, 1799 Pollination mechanisms and reproduction have a decisive bearing upon rational procedures in plant breeding and crop production. This book intends to furnish' under one cover an integrated botanical, genetical and breeding-methodologi cal treatment of the reproductive biology of spermatophytes mainly angiosperms; it is based on an advanced topical course in plant breeding taught at the Hebrew University of Jerusa lem. We have tried to present a coverage which is concise, but as comprehensive as possible, of the pollination mechanism and modes of reproduction of higher plants, and to illustrate topics, whenever practicable, by examples from cultivated plants. Nevertheless, some relevant publications may have escaped our attention or may not be mentioned because of various limitations. The book is organized into three parts. The first part starts with an evaluation of the significance of the different pollination mechanisms for plant breeding and crop produc tion, describes modes of reproduction in higher plants and discusses ecology and dynamics of pollination. The second part is devoted to crops propagated by self pollination and describes specific breeding procedures for such crops. The third part details sexual reproduction in higher plants and handles three mechanisms involved in the prevention of self pollination and their utilization in plant breeding: sex expres sion, incompatibility, and male sterility.
Publisher: Springer Science & Business Media
ISBN: 3642810594
Category : Science
Languages : en
Pages : 294
Book Description
view than its own proper males should fecundate each blossom." ANDREW KNIGHT Philosophical Transactions, 1799 Pollination mechanisms and reproduction have a decisive bearing upon rational procedures in plant breeding and crop production. This book intends to furnish' under one cover an integrated botanical, genetical and breeding-methodologi cal treatment of the reproductive biology of spermatophytes mainly angiosperms; it is based on an advanced topical course in plant breeding taught at the Hebrew University of Jerusa lem. We have tried to present a coverage which is concise, but as comprehensive as possible, of the pollination mechanism and modes of reproduction of higher plants, and to illustrate topics, whenever practicable, by examples from cultivated plants. Nevertheless, some relevant publications may have escaped our attention or may not be mentioned because of various limitations. The book is organized into three parts. The first part starts with an evaluation of the significance of the different pollination mechanisms for plant breeding and crop produc tion, describes modes of reproduction in higher plants and discusses ecology and dynamics of pollination. The second part is devoted to crops propagated by self pollination and describes specific breeding procedures for such crops. The third part details sexual reproduction in higher plants and handles three mechanisms involved in the prevention of self pollination and their utilization in plant breeding: sex expres sion, incompatibility, and male sterility.
Cloud information accountability. An overview
Author: Prem Jose Vazhacharickal
Publisher: GRIN Verlag
ISBN: 3668456208
Category : Computers
Languages : en
Pages : 75
Book Description
Scientific Study from the year 2017 in the subject Computer Science - Applied, grade: 1,5, Mar Augusthinose College, language: English, abstract: Provable data possession (PDP) is a technique for ensuring the integrity of data in storage outsourcing. In this scheme, we address the construction of an efficient PDP scheme for distributed cloud storage to support the scalability of service and data migration, in which we consider the existence of multiple cloud service providers to cooperatively store and maintain the clients’ data. We present a cooperative PDP (CPDP) scheme based on homomorphic verifiable response and hash index hierarchy. We prove the security of our scheme based on multi-prover zero-knowledge proof system, which can satisfy completeness, knowledge soundness, and zero-knowledge properties. In addition, we articulate performance optimization mechanisms for our scheme, and in particular present an efficient method for selecting optimal parameter values to minimize the computation costs of clients and storage service providers. Our experiments show that our solution introduces lower computation and communication overheads in comparison with non-cooperative approaches. Using MR-PDP to store treplicas is computationally much more efficient than using a single-replica PDP scheme to store t separate, unrelated files (e.g., by encrypting each file separately prior to storing it). Another advantage of MR-PDP is that it can generate further replicas on demand, at little expense, when some of the existing replicas fail. The generation of replicas is on demand by the user’s request that is based on the security choice selected by the user at the time of file upload. The user can choose three options Low, Medium, High at the time of file upload. The uploaded file is divided in to N blocks of different sizes to achieve the efficiency in storage and is also used to improve security, here N represent the number of clouds we are using. Low means the file is divided into N blocks (here 3), and each block is stored in N different location of the single cloud. Medium means the file is divided into N blocks and each block is stored in N different clouds which improves the security of data but reduce the availability. High means the file is divided into N blocks and each N block is stored in N different clouds that are we are keeping the replicas of file in N different clouds. The system maintains a download count to dynamically create the replicas in accordance with the users demand.
Publisher: GRIN Verlag
ISBN: 3668456208
Category : Computers
Languages : en
Pages : 75
Book Description
Scientific Study from the year 2017 in the subject Computer Science - Applied, grade: 1,5, Mar Augusthinose College, language: English, abstract: Provable data possession (PDP) is a technique for ensuring the integrity of data in storage outsourcing. In this scheme, we address the construction of an efficient PDP scheme for distributed cloud storage to support the scalability of service and data migration, in which we consider the existence of multiple cloud service providers to cooperatively store and maintain the clients’ data. We present a cooperative PDP (CPDP) scheme based on homomorphic verifiable response and hash index hierarchy. We prove the security of our scheme based on multi-prover zero-knowledge proof system, which can satisfy completeness, knowledge soundness, and zero-knowledge properties. In addition, we articulate performance optimization mechanisms for our scheme, and in particular present an efficient method for selecting optimal parameter values to minimize the computation costs of clients and storage service providers. Our experiments show that our solution introduces lower computation and communication overheads in comparison with non-cooperative approaches. Using MR-PDP to store treplicas is computationally much more efficient than using a single-replica PDP scheme to store t separate, unrelated files (e.g., by encrypting each file separately prior to storing it). Another advantage of MR-PDP is that it can generate further replicas on demand, at little expense, when some of the existing replicas fail. The generation of replicas is on demand by the user’s request that is based on the security choice selected by the user at the time of file upload. The user can choose three options Low, Medium, High at the time of file upload. The uploaded file is divided in to N blocks of different sizes to achieve the efficiency in storage and is also used to improve security, here N represent the number of clouds we are using. Low means the file is divided into N blocks (here 3), and each block is stored in N different location of the single cloud. Medium means the file is divided into N blocks and each block is stored in N different clouds which improves the security of data but reduce the availability. High means the file is divided into N blocks and each N block is stored in N different clouds that are we are keeping the replicas of file in N different clouds. The system maintains a download count to dynamically create the replicas in accordance with the users demand.
Electrical Drives and Control for Automation
Author: P. Aruna Jeyanthy
Publisher: Independently Published
ISBN: 9781983059551
Category : Education
Languages : en
Pages : 142
Book Description
Electrical drives convert electrical energy into mechanical energy and act as a intermediary between electrical supply systems, various energy sources, driven machines and the energy consumer. Electrical drives are major component in industrial applications, driven technical developments and focus of various developments. The core component of every electrical drive is the motor. This book is divided into six modules. Module 1 deals with DC machines, principles of operation, emf equation and armature reaction. Module 2 contain principles of DC motors and their torque-speed characteristics. Module 3 mainly deals with transformers and their efficiency calculations. In module 4, various aspects of induction motors were covered. Module 5 and 6 mainly focusses on split phase and stepper motors. Today electrical drives and their automation has become an essential integral part of every system and process. This book will focus primarily on electrical drives and their control for automation, although some of the topics covered will remain applicable to process control.
Publisher: Independently Published
ISBN: 9781983059551
Category : Education
Languages : en
Pages : 142
Book Description
Electrical drives convert electrical energy into mechanical energy and act as a intermediary between electrical supply systems, various energy sources, driven machines and the energy consumer. Electrical drives are major component in industrial applications, driven technical developments and focus of various developments. The core component of every electrical drive is the motor. This book is divided into six modules. Module 1 deals with DC machines, principles of operation, emf equation and armature reaction. Module 2 contain principles of DC motors and their torque-speed characteristics. Module 3 mainly deals with transformers and their efficiency calculations. In module 4, various aspects of induction motors were covered. Module 5 and 6 mainly focusses on split phase and stepper motors. Today electrical drives and their automation has become an essential integral part of every system and process. This book will focus primarily on electrical drives and their control for automation, although some of the topics covered will remain applicable to process control.
In Vitro Embryogenesis in Plants
Author: Trevor A. Thorpe
Publisher: Springer Science & Business Media
ISBN: 9780792331490
Category : Science
Languages : en
Pages : 584
Book Description
In vitro Embryogenesis in Plants is the first book devoted exclusively to this topic. As the ultimate demonstration of totipotency in plants, somatic and haploid embryogenesis is of vital importance to all those working on or interested in basic and applied aspects of plantlet information and regeneration. The text includes comprehensive reviews written by experts, on all facts of in vitro and in vivo embryogenesis. Some chapters deal with the morphogenic, structural and developmental, physiological and biochemical, and molecular biological aspects of the subject. Chapters are also devoted to haploid embryogenesis, asexual embryogenesis in nature, zygotic embryogenesis, and zygotic embryo culture. Detailed tables summarizing successful somatic embryogenesis in all vascular plants are also included. This book, therefore, brings together previously scattered information to provide an indispensable reference book for both active researchers, graduate students and anyone interested in this aspect of tissue culture technology and plant development.
Publisher: Springer Science & Business Media
ISBN: 9780792331490
Category : Science
Languages : en
Pages : 584
Book Description
In vitro Embryogenesis in Plants is the first book devoted exclusively to this topic. As the ultimate demonstration of totipotency in plants, somatic and haploid embryogenesis is of vital importance to all those working on or interested in basic and applied aspects of plantlet information and regeneration. The text includes comprehensive reviews written by experts, on all facts of in vitro and in vivo embryogenesis. Some chapters deal with the morphogenic, structural and developmental, physiological and biochemical, and molecular biological aspects of the subject. Chapters are also devoted to haploid embryogenesis, asexual embryogenesis in nature, zygotic embryogenesis, and zygotic embryo culture. Detailed tables summarizing successful somatic embryogenesis in all vascular plants are also included. This book, therefore, brings together previously scattered information to provide an indispensable reference book for both active researchers, graduate students and anyone interested in this aspect of tissue culture technology and plant development.
Cooperatives in the Global Economy
Author: Tapas R. Dash
Publisher: Rowman & Littlefield
ISBN: 1498555233
Category : Business & Economics
Languages : en
Pages : 293
Book Description
Cooperatives in the Global Economy presents a unique collection of research-based chapters contributed by leading social and economic thinkers that provide critical insights into how the cooperative business model meets the challenges of the complex global problems in today’s competitive economy. Apart from theoretical arguments in favor of the value-based cooperative business model, this book presents the performance indicators of various forms of cooperatives, their potentialities, and challenges they face across borders. The contributors reexamine how cooperatives empower the marginalized population of the world by bringing them into the mainstream of socio-economic activities through creating employment opportunities, working towards alleviation of poverty, ensuring for more equitable distribution of scarce resources, and providing the basis for a sustainable economy and its meaningful growth. Today, in the global competitive economy, the challenges for cooperatives are enormous due to their particular value commitments, forms of incorporation, and organizational structures. In spite of the presence of several challenges, cooperatives promote economic growth and social justice. In this context, this book also presents the critical roles of cooperatives in balancing economic, social, and environmental concerns to build a better, equitable, and sustainable world.
Publisher: Rowman & Littlefield
ISBN: 1498555233
Category : Business & Economics
Languages : en
Pages : 293
Book Description
Cooperatives in the Global Economy presents a unique collection of research-based chapters contributed by leading social and economic thinkers that provide critical insights into how the cooperative business model meets the challenges of the complex global problems in today’s competitive economy. Apart from theoretical arguments in favor of the value-based cooperative business model, this book presents the performance indicators of various forms of cooperatives, their potentialities, and challenges they face across borders. The contributors reexamine how cooperatives empower the marginalized population of the world by bringing them into the mainstream of socio-economic activities through creating employment opportunities, working towards alleviation of poverty, ensuring for more equitable distribution of scarce resources, and providing the basis for a sustainable economy and its meaningful growth. Today, in the global competitive economy, the challenges for cooperatives are enormous due to their particular value commitments, forms of incorporation, and organizational structures. In spite of the presence of several challenges, cooperatives promote economic growth and social justice. In this context, this book also presents the critical roles of cooperatives in balancing economic, social, and environmental concerns to build a better, equitable, and sustainable world.
Molecular Biology and Biotechnology of Plant Organelles
Author: Henry Daniell, Ph.D.
Publisher: Springer Science & Business Media
ISBN: 1402031661
Category : Science
Languages : en
Pages : 671
Book Description
We have taught plant molecular biology and biotechnology at the undergraduate and graduate level for over 20 years. In the past few decades, the field of plant organelle molecular biology and biotechnology has made immense strides. From the green revolution to golden rice, plant organelles have revolutionized agriculture. Given the exponential growth in research, the problem of finding appropriate textbooks for courses in plant biotechnology and molecular biology has become a major challenge. After years of handing out photocopies of various journal articles and reviews scattered through out the print and electronic media, a serendipitous meeting occurred at the 2002 IATPC World Congress held in Orlando, Florida. After my talk and evaluating several posters presented by investigators from my laboratory, Dr. Jacco Flipsen, Publishing Manager of Kluwer Publishers asked me whether I would consider editing a book on Plant Organelles. I accepted this challenge, after months of deliberations, primarily because I was unsuccessful in finding a text book in this area for many years. I signed the contract with Kluwer in March 2003 with a promise to deliver a camera-ready textbook on July 1, 2004. Given the short deadline and the complexity of the task, I quickly realized this task would need a co-editor. Dr. Christine Chase was the first scientist who came to my mind because of her expertise in plant mitochondria, and she readily agreed to work with me on this book.
Publisher: Springer Science & Business Media
ISBN: 1402031661
Category : Science
Languages : en
Pages : 671
Book Description
We have taught plant molecular biology and biotechnology at the undergraduate and graduate level for over 20 years. In the past few decades, the field of plant organelle molecular biology and biotechnology has made immense strides. From the green revolution to golden rice, plant organelles have revolutionized agriculture. Given the exponential growth in research, the problem of finding appropriate textbooks for courses in plant biotechnology and molecular biology has become a major challenge. After years of handing out photocopies of various journal articles and reviews scattered through out the print and electronic media, a serendipitous meeting occurred at the 2002 IATPC World Congress held in Orlando, Florida. After my talk and evaluating several posters presented by investigators from my laboratory, Dr. Jacco Flipsen, Publishing Manager of Kluwer Publishers asked me whether I would consider editing a book on Plant Organelles. I accepted this challenge, after months of deliberations, primarily because I was unsuccessful in finding a text book in this area for many years. I signed the contract with Kluwer in March 2003 with a promise to deliver a camera-ready textbook on July 1, 2004. Given the short deadline and the complexity of the task, I quickly realized this task would need a co-editor. Dr. Christine Chase was the first scientist who came to my mind because of her expertise in plant mitochondria, and she readily agreed to work with me on this book.
Flower Seeds
Author: M. B. McDonald
Publisher: Cabi
ISBN: 9780851999067
Category : Gardening
Languages : en
Pages : 372
Book Description
The floral industry represents a significant proportion of agricultural income in several developed countries, particularly the USA, the Netherlands and Japan. Hitherto, the sheer diversity of flower seeds, in their form, function and biology, has hindered the production of a comprehensive treatment of the topic. This book provides a unique and much-needed resource of information on the biology and technology of flower seeds. It presents in-depth information on the history and evolution of the ornamental and wild flower seed industries followed by recommendations for successful breed and production programs. A comprehensive coverage of the biology of flower seeds is considered as well as appropriate technologies associated with germination, vigor and viability testing. In this volume, the first of its kind, international authorities from academia and industry have been brought together to provide a comprehensive reference resource for both practitioners and students of seed science and technology and of ornamental horticulture.
Publisher: Cabi
ISBN: 9780851999067
Category : Gardening
Languages : en
Pages : 372
Book Description
The floral industry represents a significant proportion of agricultural income in several developed countries, particularly the USA, the Netherlands and Japan. Hitherto, the sheer diversity of flower seeds, in their form, function and biology, has hindered the production of a comprehensive treatment of the topic. This book provides a unique and much-needed resource of information on the biology and technology of flower seeds. It presents in-depth information on the history and evolution of the ornamental and wild flower seed industries followed by recommendations for successful breed and production programs. A comprehensive coverage of the biology of flower seeds is considered as well as appropriate technologies associated with germination, vigor and viability testing. In this volume, the first of its kind, international authorities from academia and industry have been brought together to provide a comprehensive reference resource for both practitioners and students of seed science and technology and of ornamental horticulture.
Plant-microbe Interactions 2
Author: Gary Stacey
Publisher: Springer Science & Business Media
ISBN: 1461560535
Category : Science
Languages : en
Pages : 238
Book Description
Plant-Microbe Interactions, Volume 2 Volume 1 of this series has made its appearance and dealt forcefully with impor tant current topics in the field of plant-microbe interactions. We believe that the quality of those chapters was high and should serve as a focal point for the state of the art as well as an enduring reference. Volume 2 builds upon these accom plishments. Chapter 1 discusses the fascinating lipo-chitin signal molecules from Rhizo bium, aspects regarding their biosynthesis, and the basis for host specificity. These molecules are a cardinal example of how microorganisms influence plant development and stimulate speculation that they have identified a previously un known aspect of plant hormone activity. Chapter 2 continues the discussion of Rhizobium by considering the trafficking of carbon and nitrogen in nodules. Al though the ostensible advantage of nodules to plants is the fixation of atmos pheric nitrogen, the actual process involved in supplying reduced nitrogen to the plant host is complex.
Publisher: Springer Science & Business Media
ISBN: 1461560535
Category : Science
Languages : en
Pages : 238
Book Description
Plant-Microbe Interactions, Volume 2 Volume 1 of this series has made its appearance and dealt forcefully with impor tant current topics in the field of plant-microbe interactions. We believe that the quality of those chapters was high and should serve as a focal point for the state of the art as well as an enduring reference. Volume 2 builds upon these accom plishments. Chapter 1 discusses the fascinating lipo-chitin signal molecules from Rhizo bium, aspects regarding their biosynthesis, and the basis for host specificity. These molecules are a cardinal example of how microorganisms influence plant development and stimulate speculation that they have identified a previously un known aspect of plant hormone activity. Chapter 2 continues the discussion of Rhizobium by considering the trafficking of carbon and nitrogen in nodules. Al though the ostensible advantage of nodules to plants is the fixation of atmos pheric nitrogen, the actual process involved in supplying reduced nitrogen to the plant host is complex.