Download or read book Haustorium Development in the Parasitic Plant Triphysaria Orobanchaceae written by Denneal Sarah Jamison-McClung and published by . This book was released on 2003 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Roles of Kin recognition Redox Signaling and Nitrogen Transport in Haustorium Development in Triphysaria Versicolor and Control of Root Parasitic Weeds written by Yaxin Wang and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Parasitic weeds are among the world's most economically damaging agricultural pests. Root parasitic weeds such as witchweeds (Striga) and broomrapes (Orobanche) attack a large number of crops, including corn, rice, sorghum, sunflower and tomato. While progress has been made in reducing Striga damage through cultural practices, no robust biocontrol method has yet been developed in host crops. Our lab uses the parasitic plant Triphysaria as a model system to study parasite-host interactions. Triphysaria is a non-weedy hemiparasite in the Orobanchaceae, the same family that includes Striga and Orobanche. Root parasitic plants develop novel root structures named haustoria that enable them to attach to and invade host plants for water and nutrients. Development of haustoria is initiated in response to haustorium inducing factors (HIFs) released by host plants. The development and successful invasion of host tissues by the haustorium are critical events in the parasitic lifestyle and provide potential targets for parasitic weed control strategies. The ultimate goal of my research is to understand the fundamental mechanisms of haustorium development and host-parasite interacts and develop biocontrol methods against parasitic weeds. I studied haustorium development in Triphysaria from three perspectives: HIF production, HIF perception and nutrient transport across the haustorium. In the first chapter I provide an overview of parasitic Orobanchaceae and the development of haustoria. In the second chapter, I describe results from my investigations into self and kin recognition in Triphysaria, the natural mechanisms by which Triphysaria avoids parasitizing itself or its kin species. The kin-recognition mechanism may potentially be engineered into crop species to make them invisible to parasitic weeds. In the third chapter, I looked into the importance of ROS signaling in HIF perception and haustorium development. Disruption of ROS signaling in parasitic plants provides another strategy to prevent haustorium development in parasitic weeds. In fourth chapter, amino acids transport from host to parasite was examined. The preferentially transported and accumulated amino acids in parasites provide targets to disrupt nutrient reliance of parasitic plants on the host plants. I will conclude with some thoughts on how my studies might eventually be translated into robust, genetic control of parasitic weeds.
Download or read book Parasitic Orobanchaceae written by Daniel M. Joel and published by Springer Science & Business Media. This book was released on 2013-07-01 with total page 519 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book was written in response to significant recent advances in understanding the mechanisms of parasitism in the Orobanchaceae, and breakthroughs in the control of the parasitic weeds Striga and Orobanche. It consists of 26 contributions by internationally recognized leading scientists. The main book chapters are grouped into two parts: · Part I – The Orobanchaceae and Their Parasitic Mechanisms · Part II – The Weedy Orobanchaceae and Their Control The first part provides cutting-edge information on all key aspects of plant parasitism, such as the structure, development and function of the haustorium; nutrient transfer and the physiology of the parasite-host association; host reaction to parasitic plants; seed production and germination; the strigolactones and host-parasite signaling mechanisms; the parasite genome, phylogenetics, evolution and epigenetics; and ecology. Topics of the second part include: the problem posed by the weedy parasites; population diversity and dynamics; molecular diagnosis of seed banks; and detailed discussion of the various management strategies, including agronomic, chemical and biotechnological approaches, as well as host breeding for resistance, allelopathy and biological control. This book is intended for plant scientists, university lecturers and students, agronomists and weed specialists, breeders and farmers, extension personnel and experts in tropical and subtropical agriculture.
Download or read book The Haustorium written by N. N. Bhandari and published by *Research Studies Press. This book was released on 1993-11-02 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents and collates information on all types of haustoria and is designed as a standard reference for work in this field. The ultrastructure and function of haustoria are discussed and the different morphological types of angiosperms, fungi and vesicular arbuscular mycorrhizae are examined.
Download or read book Parasitic flowering plants written by Henning Heide-Jørgensen and published by BRILL. This book was released on 2008-07-31 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: Parasitic flowering plants are strikingly impressive and beautiful and hold many surprises of both general and scientific interest. Parasites also have great influence on the quality of human life when attacking crop plants. Some parasites have since early times appealed to our imagination and have been part of religious or folkloristic events and used as gifts to royalties. This beautifully illustrated book covers all parasitic families and most of the genera. It also discusses the establishment of the parasite, the structure and function of the nutrient absorption organ (haustorium), and how the parasites are pollinated and dispersed as well as their ecology, hosts, and evolution. The book is written in a mostly non-technical language and is provided with a glossary and explanatory boxes. For additional information about this book, including some sample photographs, as well as a list of corrections that have been incorporated in the 2011 reprint, please visit the author's web site. Parasitic Flowering Plants was nominated by The Council on Botanical and Horticultural Libraries for the 2010 Annual Award for a Significant Work in Botanical or Horticular Literature, in the category ‘Technical Interest’. More information.
Download or read book The Biology of Parasitic Flowering Plants written by Job Kuijt and published by . This book was released on 1969 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evolution und Systematik.
Download or read book Comparative Genomics and RNAi Silencing to Control Parasitic Weeds and Dissect the Signaling of Haustorium Development written by Pradeepa Chandani Gunathilake Bandaranayake and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Parasitic plants directly invade other plants in order to rob them of water, nutrients and carbohydrates. The Orobanchaceae is a monophyletic family of root parasitic plants that includes some of the world's most destructive agricultural weeds, such as Striga, and Orobanche. Triphysaria is a non-weedy, facultative parasite in Orobanchaceae that infects a broad range of hosts and is used as a model parasite system. Host attachment, invasion and resource acquisition is mediated through a parasite-specific organ called the haustorium. Parasitic plants in the Orobanchaceae respond to chemical stimuli provided by contact with host roots or host root factors to develop haustoria that invade host roots and establish the physiological bridge through which resources are translocated. The goals of my thesis work was to (1) identify and characterize some of the genes encoding the haustorial signal transduction pathway in Triphysaria and (2) to develop a biological strategy to control parasitic weeds. RNA interference (RNAi) technology was used to reduce transcripts of candidate genes in Triphysaria roots that were then evaluated for their ability to form haustoria. To perform these experiments, I first modified a Gateway compatible RNAi transformation vector by adding yellow florescence protein (YFP) reporter gene under the control of mas-1 promoter. I also modified an Agrobacterium rhizogenes root transformation system for Triphysaria and increased the transformation frequency about 30 fold compared to the lab's previous protocol. In the first chapter, I describe my characterization of three candidate genes involved in the earliest stage in host factor recognition. My first set of experiments tested the hypothesis that quinolic-inducing factors activate haustorium development via a signal mechanism initiated by redox cycling between quinone and hydroquinone states. Previous members in the lab isolated two cDNAs, TvQR1 and TvQR2, from Triphysaria roots that encode distinct classes of quinone oxidoreductases. TvQR1 encodes a single-electron reducing NADPH quinone oxidoreductase similar to other zeta-crystallin quinone reductases. In contrast, the TvQR2 enzyme catalyzes two electron reductions typical of xenobiotic detoxification. When RNAi was used to reduce TvQR1 and TvQR2 transcripts, there was a significant decrease in haustorium development in roots silenced for TvQR1 but not in roots silenced for TvQR2. The small percentage of TvQR1 transgenic roots that did form haustoria had TvQR1 transcript levels similar to non silenced control roots. These results suggest that TvQR1 is the first gene on the haustorium signal transduction pathway. The next set of experiments tested the hypothesis that the transcription factor binding protein TvPIRIN has a role in haustorium formation. TvPIRIN is upregulated in Triphysaria roots early in response to host roots and chemical haustorium inducing factors (HIFs). I used a similar RNAi strategy as with TvQR1 and showed there was a significant decrease in haustorium development in roots silenced for TvPIRIN. I treated Triphysaria roots with the G-protein pathway stimulator mastoparan and showed it could partially supplement the requirement of HIF for haustorium formation in Triphysaria seedlings. I propose that TvPIRIN may act as a transcription factor that binds the G-protein alpha subunit activating a signaling chain leading to haustorium development. Flavonoids play a variety of roles in plants from flower color to signaling. My objectives of the experiments described in the third chapter were to investigate the role of flavonoids in haustorium development. Two genes in flavonoid biosynthetic pathway; phenylalanine ammonia-lyase (TvPAL) which catalyzes the first step in the phenylpropanoid pathway, and chalcone isomerase (TvCHI) which codes for the second enzyme in the flavonoid biosynthesis branch, were silenced using RNAi technology. While TvCHI silenced roots grew normally, a significant portion of TvPAL silenced roots showed abnormal phenotypes. I assayed the most normal transgenic roots for haustorium development and determined that there was a significant decrease in haustorium development in roots silenced for TvPAL but not in roots silenced for TvCHI. In the fourth chapter, I describe my analyses of gene expression patterns in transgenic roots silenced for TvQR1, TvQR2 or TvPIRIN to further our knowledge about genes involved in haustorium signaling. I analyzed the expression of six genes that are regulated by HIFs and one gene that is not using quantitative RT-PCR. My results showed that TvPIRIN regulates the expression of several other genes, furthering the suggestion that is functions as a transcription factor. The goal of the experiments describe in the fifth chapter was to develop a biological based strategy to control parasitic weeds. My hypothesis was that introducing RNAi constructs specifically targeting parasite genes essential for survival into host roots would stop the growth of parasite roots attached to the transgenic host root. Three candidate genes were selected based on their mutant phenotypes, if they are herbicide targets or both. Hairpin constructions were transformed into the selected host, Medicago truncatula: cytosolic acetyl-CoA carboxylase (TvACC1), alpha-subunit of chloroplast acetyl-CoA carboxylase (TvAlpha) and enolpyruvylshikimate 3-phosphate synthase (TvEPSP). TvACC1 transformed M. truncatula roots were severely stunted unless treated with malonate, the product of the ACC1 enzyme. When ACC1 silenced roots were infected with Triphysaria, the Triphysaria roots stopped growing and their tips died within a week of infection. While this appears to be an effective method to stop Triphysaria infections in vitro, it has yet to be tested under field conditions. These experiments provide insight into how free living plants acquire a parasitic lifestyle by responding to host released factors and suggest a novel control strategy.
Download or read book Integrating New Technologies for Striga Control written by Gebisa Ejeta and published by World Scientific. This book was released on 2007 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: Witchweeds (Striga species) decimate agriculture in much of Africa and parts of Asia, attacking the major cereal grains and legumes, and halving the already very low yields of subsistence farmers. Several years of research have provided promising technologies, based on the fundamental biology of the parasite?host associations, for dealing with this scourge. However, there is an apparent realization that these technologies will fail because highly successful weeds such as Striga evolve resistance to all types of controls unless proven methods are integrated with each other for a more sustainable solution.Integration is often an anathema to basic scientists who typically deal with single variables and solutions. However, key leaders in the development of the new knowledge-based control strategies, already in the field and under development, recently joined forces to develop strategies and projects in order to integrate the technologies in a symposium in Ethiopia in November 2006. The encouraging results are described in this peer-reviewed book, authored by leaders in the field who have been supplying the basic biology, genetics, biochemistry, and molecular information that have offered insights and generated technologies in how to deal with Striga.
Download or read book A Materia Medica for Chinese Medicine written by Carl-Hermann Hempen and published by Elsevier Health Sciences. This book was released on 2009-01-01 with total page 1019 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phytotherapy or herbal medicine is the most important therapy within Chinese medicine and is being used increasingly in the West. A Materia Medica for Chinese Medicine: plants, minerals and animal products describes 400 of the most important plants, minerals and animal substances used as treatments by Chinese medical practitioners. The items included have been selected according to their degree of clinical relevance. Each remedy is clearly described and illustrated on two facing pages, making this an easily accessible reference for both students and practitioners of Chinese herbal medicine. The clearly laid out text presents the following details for each herb or substance included: a detailed description of the characteristic features indictions for safe use medicinal and toxic effects possible combinations with other substances full-colour illustrations, generally two for each substance, showing the detailed characterisitcs of the item described A Materia Medica for Chinese Medicine has been written by two medically trained doctors who have worked as TCM therapists specializing in the use of Chinese herbs for more than 30 years. Based on their many years of teaching and practice, the book has been carefully compiled and designed to provide a concise and accurate practice-based reference for both students and practitioners.
Download or read book Seedling Ecology and Evolution written by Mary Allessio Leck and published by Cambridge University Press. This book was released on 2008-09-18 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seedlings are highly sensitive to their environment. After seeds, they typically suffer the highest mortality of any life history stage. This book provides a comprehensive exploration of the seedling stage of the plant life cycle. It considers the importance of seedlings in plant communities; environmental factors with special impact on seedlings; the morphological and physiological diversity of seedlings including mycorrhizae; the relationship of the seedling with other life stages; seedling evolution; and seedlings in human altered ecosystems, including deserts, tropical rainforests, and habitat restoration projects. The diversity of seedlings is portrayed by including specialised groups like orchids, bromeliads, and parasitic and carnivorous plants. Discussions of physiology, morphology, evolution and ecology are brought together to focus on how and why seedlings are successful. This important text sets the stage for future research and is valuable to graduate students and researchers in plant ecology, botany, agriculture and conservation.
Download or read book Common Grasses Legumes and Forbs of the Eastern United States written by A.Ozzie Abaye and published by Academic Press. This book was released on 2018-09-14 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: Common Grasses, Legumes and Forbs of the Eastern United States: Identification and Adaptation presents photographic identification of the most important grassland, turf, and noncrop plants, and their seeds to facilitate quick identification in the field. Unlike many publications that focus solely on floral identification, this book emphasizes vegetative identification as well to allow for accurate plant identification year-round. The book includes 23 forage legumes, 61 grasses, and more than 100 nonleguminous forbs found in pastures and grasslands of Eastern United States. In addition to identification of important species, the book describes other key characteristics such as adaptation, favorable and unfavorable soil types, seasonal growth patterns, and toxicity. For plants harvested for hay or silage or by grazing, the book also discusses cutting and grazing management, quality factors, and potential yields. Through its practical approach and comprehensive structure, Common Grasses, Legumes and Forbs of the Eastern United States is a valuable reference for farm advisors, teachers and students of agronomy, and for anyone interested in the dynamic relationship between plants and agriculture. - Features full-color illustrations of both seed and plant, allowing for rapid identification at multiple stages of development - Presents various identification methods and use cases for over 180 plants - Details seasonal growth patterns and toxicity, as well as favorable and unfavorable soil types - Discusses cutting and grazing management
Download or read book Weed Ecology written by Steven R. Radosevich and published by John Wiley & Sons. This book was released on 1997-02-05 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt: Weeds are successful plants, but on their own terms. Looking at weeds from an ecological viewpoint, emphasising the way in which one species interacts with others, the authors show that weeds are questionable mainly in that they are out-of-place.
Download or read book Hormone Metabolism and Signaling in Plants written by Jiayang Li and published by Academic Press. This book was released on 2017-04-19 with total page 618 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plant Hormones: Biosynthesis and Mechanisms of Action is based on research funded by the Chinese government's National Natural Science Foundation of China (NSFC). This book brings a fresh understanding of hormone biology, particularly molecular mechanisms driving plant hormone actions. With growing understanding of hormone biology comes new outlooks on how mankind values and utilizes the built-in potential of plants for improvement of crops in an environmentally friendly and sustainable manner. This book is a comprehensive description of all major plant hormones: how they are synthesized and catabolized; how they are perceived by plant cells; how they trigger signal transduction; how they regulate gene expression; how they regulate plant growth, development and defense responses; and how we measure plant hormones. This is an exciting time for researchers interested in plant hormones. Plants rely on a diverse set of small molecule hormones to regulate every aspect of their biological processes including development, growth, and adaptation. Since the discovery of the first plant hormone auxin, hormones have always been the frontiers of plant biology. Although the physiological functions of most plant hormones have been studied for decades, the last 15 to 20 years have seen a dramatic progress in our understanding of the molecular mechanisms of hormone actions. The publication of the whole genome sequences of the model systems of Arabidopsis and rice, together with the advent of multidisciplinary approaches has opened the door to successful experimentation on plant hormone actions. - Offers a comprehensive description of all major plant hormones including the recently discovered strigolactones and several peptide hormones - Contains a chapter describing how plant hormones regulate stem cells - Offers a fresh understanding of hormone biology, particularly molecular mechanisms driving plant hormone actions - Discusses the built-in potential of plants for improvement of crops in an environmentally friendly and sustainable manner
Download or read book Molecular Systematics of Plants II written by Pamela Soltis and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the five years since the publication of Molecular Systematics of Plants, the field of molecular systematics has advanced at an astonishing pace. This period has been marked by a volume of new empirical data and advances in theoretical and analytical issues related to DNA. Comparative DNA sequencing, facilitated by the amplification of DNA via the polymerase chain reaction (PCR), has become the tool of choice for molecular systematics. As a result, large portions of the Molecular Systematics of Plants have become outdated. Molecular Systematics of Plants II summarizes these recent achievements in plant molecular systematics. Like its predecessor, this completely revised work illustrates the potential of DNA markers for addressing a wide variety of phylogenetic and evolutionary questions. The volume provides guidance in choosing appropriate techniques, as well as appropriate genes for sequencing, for given levels of systematic inquiry. More than a review of techniques and previous work, Molecular Systematics of Plants II provides a stimulus for developing future research in this rapidly evolving field. Molecular Systematics of Plants II is not only written for systematists (faculty, graduate students, and researchers), but also for evolutionary biologists, botanists, and paleobotanists interested in reviewing current theory and practice in plant molecular systematics.
Download or read book Striga biology and Control written by Edward S. Ayensu and published by . This book was released on 1984 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Secretions and Exudates in Biological Systems written by Jorge M. Vivanco and published by Springer Science & Business Media. This book was released on 2012-01-21 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Secretions and emissions in biological systems play important signaling roles within the organism but also in its communications with the surrounding environment. This volume brings together state-of-the-art information on the role of secretions and emissions in different organs and organisms ranging from flowers and roots of plants to nematodes and human organs. The plant chapters relate information regarding the biochemistry of flower volatiles and root exudates, and their role in attracting pollinators and soil microbial communities respectively. Microbial chapters explain the biochemistry and ecology of quorum sensing and how microbial communities highly co-adapted to plants can aid in bio-energy applications by degrading ligno-cellulosic materials. Other chapters explain the biology of secretions by nematodes, algae and humans, among other organisms. This volume will be a welcome addition to the literature, as no other book covers aspects related to biological secretion in such a holistic and integrative manner.
Download or read book Weed Biology and Management written by Inderjit and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt: Weeds hold an enigmatic and sometimes-controversial place in agriculture, where they are generally reviled, grudgingly tolerated, and occasionally admired. In most cases, growers make considerable effort to reduce the negative economic impact of weeds because they compete with crops for resources and hinder field operations, thereby affecting crop productivity and quality, and ultimately the sustainability of agriculture. Weed control in production agriculture is commonly achieved through the integration of chemical, biological, and mechanical management methods. Chemicals (herbicides) usually inhibit the growth and establishment of weed plants by interfering with various physiological and biochemical pathways. Biological methods include crop competition, smother crops, rotation crops, and allelopathy, as well as specific insect predators and plant pathogens. Mechanical methods encompass an array of tools from short handled hoes to sophisticated video-guided robotic machines. Integrating these technologies, in order to relieve the negative impacts of weeds on crop production in a way that allows growers to optimize profits and preserve human health and the environment, is the science of weed management.
