Download or read book Towards Identifying the Physiological and Molecular Basis of Drought Tolerance in Cassava Manihot esculenta Crantz written by Rosemary Wanja Mutegi-Murori and published by Cuvillier Verlag. This book was released on 2010-02-10 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drought is one of the most important factors limiting crop production in sub-Saharan Africa. This has detrimental effects to the people living in this region, and whose population is increasing more rapidly than their domestic food production. Noticeably, pressure on agricultural land has continued to intensify. Cassava is one of the staple crops with remarkable tolerance to drought. It is adapted to diverse and poor soil conditions, in addition to its flexibility in planting and harvesting times. Understanding its physiological and molecular basis of drought tolerance may help to target the key traits that limit crop yield under drought conditions. To improve our understanding on drought tolerance mechanisms in cassava, the project "Identifying the physiological and genetic traits that make cassava one of the most drought-tolerant crops" was initiated in 2005 by the Brazilian Agricultural Research Corporation (Embrapa) in collaboration with the International Center for Tropical Agriculture (CIAT); the International Institute of Tropical Agriculture (IITA); Cornell University and University of Goettingen. The ultimate goal of the project was to identify morphological, physiological and molecular traits related to drought tolerance mechanisms in cassava for further progress, and for their application in cassava and other crop breeding programs. The present study was conducted within the framework of this project with 31 African cassava germplasm accessions from IITA and a mapping population developed at CIAT. The objectives of this study were, 1) To develop a protocol for hardening and rapid micro-propagation of cassava plantlets under local, low-cost conditions; 2) To identify agro-morphological attributes that are related to drought tolerance in cassava; 3) To identify drought-tolerant and drought-susceptible cassava germplasm from a selection of African accessions; 4) To identify secondary traits that could be used for phenotyping breeding materials for drought tolerance; 5) To screen the CIAT mapping population with simple sequence repeats (SSR) and expressed simple sequence repeat (ESSR) markers for linkage analysis. Thirty one putative drought-tolerant and drought-susceptible African cassava germplasm accessions from IITA were micro-propagated using direct and in-direct techniques, at Kenya Agricultural Research Institute (KARI), Nairobi, Kenya. In direct micro-propagation, plantlets were hardened using vermiculite and multiplied through nodal cuttings. In in-direct micro-propagation, plantlets were first multiplied through sub-culturing and later hardened. The direct micro-propagation method had a higher multiplication rate. The number of plantlets obtained in 7 months using the direct method were 1173 as compared to 722 attained using the in-direct micropropagation. Rapid micro-propagation through nodal cuttings was cheaper in terms of consumables and an effective alternative to enhance rates of multiplication, over the in-direct method and the more conventional technique like the use of stem cuttings. Agronomic and morphological evaluation of contrasting African cassava germplasm accessions was carried out in water-stressed and well-watered environments at 5 time points. The trial was conducted at the experimental field of KARI, Kiboko Research Station in Makindu, Eastern Kenya, a site characterized by Acri-orthic Ferralsol soil. Analysis of variance was performed using the agronomic and morphological data, and broad sense heritability was estimated. In general, significant differences were observed among the accessions, suggesting a strong genetic basis for the phenotypic variation observed. Variation was also notable in water-stressed and well-watered environments for a majority of traits evaluated. This was due to the artificial water applied since, during the trial period, there was hardly any rainfall. At harvest, leaf length and width of certain accessions at the water-stressed site approached that of the well-watered treatment. On average, the estimated mean percentage leaf retention was high in the well-watered treatment. However, leaf retention in some of the accessions assessed was almost the same in both treatments. These accessions tended to produce higher yields. Thus, it may be desirable to select for higher leaf retention when developing varieties adapted to dry areas. The range of yields under stress was from 3.3 to 36.7 kg/m2, whereas, under the well-watered treatment, it was smaller: 28.3 to 53.3 kg/m2. Differences among accessions in yield and overall above-ground fresh biomass showed that these are important primary traits to phenotype germplasm under favorable and water-stress conditions. In addition, 4 accessions G26, G11, G8 and G31 were more tolerant than the rest of the genotypes evaluated, calling for further research and their involvement in agricultural experimentation under drought-prone conditions. Considering relationships between traits, genotype ability for both accumulation of above-ground fresh biomass and to partition carbon into roots (harvest index) were among the traits most correlated with root yield. However, accessions, environment and the interaction of both influenced the traits strongly. Thus, it is important that agro-morphological field trials be conducted in several locations for several seasons for effective evaluation of their influences on traits that might be relevant for phenotypically assessing drought tolerance. Unlike for agro-morphological traits, where a drought-tolerant accession could be identified from the yield, which is of primary concern, selection of an outstanding accession in a water-limited environment using metabolic traits was not achieved in this study. Maybe the well-watered plants experienced an incipient stress due to low humidity, symptomless diseases or nutrient deficiency, which was not ascertained in this study. Despite this, significant differences were observed between the waterstressed and well-watered treatments for the traits evaluated, except protein and amylose content. Performance in individuals was variable, although insignificant differences were observed between the different stress phases. Changes in sugar concentration have a role in the drought-tolerance of the accessions evaluated, although, their relative contribution to drought stress could not be determined from the available data. Further work is imperative to identify and quantify sugar concentrations in relation to osmotic adjustment in these accessions. In addition, further research to determine the time course of ABA accumulation, as a cassava plant goes from its young stage to aging, is required so as to know the stage at which ABA data are most informative. Two genetic linkage maps were constructed using a South American mapping population of 228 individuals derived from a cross between a drought-tolerant and a drought-susceptible parent. A set of 377 simple sequence repeats (SSR) and expressed simple sequence repeats (ESSR’s) were utilized for the initial polymorphism screening. Differences in map size, interval, number and mean distance between markers were apparent between the two maps. The female map had 14 linkage groups as compared to 13 in the male map. Twenty seven allelic bridges were noticeable between the two maps. In addition, 25 markers showed collineality with other available cassava maps. Forty six markers, whose map distances had not been determined previously, were mapped in this study. These maps form an important platform upon which to characterize the genetic basis of drought tolerance in cassava. Continued addition of more markers in these maps will refine the utility of the resource for future cassava breeding efforts. In conclusion, four African cassava accessions apparently have the ability to withstand severe drought. However, a majority of the accessions evaluated gave poor response in adaptability to water-limited conditions. This suggests that further agroecologically based research is required on these materials, since they represent diverse improved accessions from IITA breeding activities. This, coupled with markerassisted genetic analysis, would be an appropriate approach for the identification of drought-tolerant accessions.
Download or read book Drought phenotyping in crops From theory to practice written by Philippe Monneveux and published by Frontiers E-books. This book was released on 2014-02-12 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: This topic is a unique attempt to simultaneously tackle theoretical and practical aspects in drought phenotyping, through both crop-specific and cross-cutting approaches. It is designed for – and will be of use to – practitioners and postgraduate students in plant science, who are grappling with the challenging task of evaluating germplasm performance under different water regimes. In Part I, different methodologies are presented for accurately characterising environmental conditions, implementing trials, and capturing and analysing the information this generates, regardless of the crop. Part II presents the state-of-art in research on adaptation to drought, and recommends specific protocols to measure different traits in major food crops (focusing on particular cereals, legumes and clonal crops). The topic is part of the CGIAR Generation Challenge Programme’s efforts to disseminate crop research information, tools and protocols, for improving characterisation of environments and phenotyping conditions. The goal is to enhance expertise in testing locations, and to stimulate the development and use of traits related to drought tolerance, as well as innovative protocols for crop characterisation and breeding.
Download or read book Cassava written by R. J. Hillocks and published by CABI. This book was released on 2002 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cassava is a major tropical tuber crop found throughout the tropics (India, Oceania, Africa and Latin America). Hitherto, there has been no single text covering all aspects of cassava biology, production and utilization. This book fills that gap, representing the first comprehensive research level overview of this main staple crop. Chapters are written by leading experts in this field from all continents. The book is suitable for those working and researching in cassava, in both developed and developing countries, as well as advanced students.
Download or read book Genomic Designing for Abiotic Stress Resistant Technical Crops written by Chittaranjan Kole and published by Springer Nature. This book was released on 2022-10-31 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents deliberations on molecular and genomic mechanisms underlying the interactions of crop plants to the abiotic stresses caused by heat, cold, drought, flooding, submergence, salinity, acidity, etc., important to develop resistant crop varieties. Knowledge on the advanced genetic and genomic crop improvement strategies including molecular breeding, transgenics, genomic-assisted breeding, and the recently emerging genome editing for developing resistant varieties in technical crops is imperative for addressing FHNEE (food, health, nutrition, energy, and environment) security. Whole genome sequencing in many of these crops followed by genotyping-by-sequencing has provided precise information regarding the genes conferring resistance useful for gene discovery, allele mining, and shuttle breeding which in turn opened up the scope for 'designing' crop genomes with resistance to abiotic stresses. The ten chapters each dedicated to a technical crop and one chapter devoted to a crop group in this volume elucidate different types of abiotic stresses and their effects on and interaction with the crops; enumerate the available genetic diversity with regard to abiotic stress resistance among available cultivars; illuminate the potential gene pools for utilization in interspecific gene transfer; present brief on classical genetics of stress resistance and traditional breeding for transferring them to their cultivated counterparts; depict the success stories of genetic engineering for developing abiotic stress-resistant crop varieties; discuss on molecular mapping of genes and QTLs underlying stress resistance and their marker-assisted introgression into elite varieties; enunciate different genomics-aided techniques including genomic selection, allele mining, gene discovery, and gene pyramiding for developing adaptive crop varieties with higher quantity and quality of yields, and also elaborate some case studies on genome editing focusing on specific genes for generating abiotic stress-resistant crops.
Download or read book Advances in Molecular Breeding Toward Drought and Salt Tolerant Crops written by Matthew A. Jenks and published by Springer Science & Business Media. This book was released on 2009-05-07 with total page 819 pages. Available in PDF, EPUB and Kindle. Book excerpt: With near-comprehensive coverage of new advances in crop breeding for drought and salinity stress tolerance, this timely work seeks to integrate the most recent findings about key biological determinants of plant stress tolerance with modern crop improvement strategies. This volume is unique because is provides exceptionally wide coverage of current knowledge and expertise being applied in drought and salt tolerance research.
Download or read book Crop Physiology Case Histories for Major Crops written by Victor Sadras and published by Academic Press. This book was released on 2020-12-05 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crop Physiology: Case Histories of Major Crops updates the physiology of broad-acre crops with a focus on the genetic, environmental and management drivers of development, capture and efficiency in the use of radiation, water and nutrients, the formation of yield and aspects of quality. These physiological process are presented in a double context of challenges and solutions. The challenges to increase plant-based food, fodder, fiber and energy against the backdrop of population increase, climate change, dietary choices and declining public funding for research and development in agriculture are unprecedented and urgent. The proximal technological solutions to these challenges are genetic improvement and agronomy. Hence, the premise of the book is that crop physiology is most valuable when it engages meaningfully with breeding and agronomy. With contributions from 92 leading scientists from around the world, each chapter deals with a crop: maize, rice, wheat, barley, sorghum and oat; quinoa; soybean, field pea, chickpea, peanut, common bean, lentil, lupin and faba bean; sunflower and canola; potato, cassava, sugar beet and sugarcane; and cotton. A crop-based approach to crop physiology in a G x E x M context Captures the perspectives of global experts on 22 crops
Download or read book Food Security and Climate Change written by Shyam Singh Yadav and published by John Wiley & Sons. This book was released on 2018-12-14 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book looks at the current state of food security and climate change, discusses the issues that are affecting them, and the actions required to ensure there will be enough food for the future. By casting a much wider net than most previously published books—to include select novel approaches, techniques, genes from crop diverse genetic resources or relatives—it shows how agriculture may still be able to triumph over the very real threat of climate change. Food Security and Climate Change integrates various challenges posed by changing climate, increasing population, sustainability in crop productivity, demand for food grains to sustain food security, and the anticipated future need for nutritious quality foods. It looks at individual factors resulting from climate change, including rising carbon emission levels, increasing temperature, disruptions in rainfall patterns, drought, and their combined impact on planting environments, crop adaptation, production, and management. The role of plant genetic resources, breeding technologies of crops, biotechnologies, and integrated farm management and agronomic good practices are included, and demonstrate the significance of food grain production in achieving food security during climate change. Food Security and Climate Change is an excellent book for researchers, scientists, students, and policy makers involved in agricultural science and technology, as well as those concerned with the effects of climate change on our environment and the food industry.
Download or read book Tropical Roots and Tubers written by Harish K. Sharma and published by John Wiley & Sons. This book was released on 2016-11-14 with total page 646 pages. Available in PDF, EPUB and Kindle. Book excerpt: Roots and tubers are considered as the most important food crops after cereals and contribute significantly to sustainable development, income generation and food security especially in the tropical regions. The perishable nature of roots and tubers demands appropriate storage conditions at different stages starting from farmers to its final consumers. Because of their highly perishable nature, search for efficient and better methods of preservation/processing have been continuing alongside the developments in different arena. This book covers the processing and technological aspects of root and tuber foods, detailing the production and processing of roots and tubers such as taro, cassava, sweet potato, yam and elephant foot yam. Featuring chapters on anatomy, taxonomy and physiology, molecular and biochemical characterization, GAP, GMP, HACCP, Storage techniques, as well as the latest technological interventions in Taro, Cassava, Sweet potato, yam and Elephant foot Yam.
Download or read book Improving Stress Resilience in Plants written by Mohammad Abass Ahanger and published by Elsevier. This book was released on 2023-11-23 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt: Improving Stress Resilience in Plants: Physiological and Biochemical Basis and Utilization in Breeding addresses the urgent need for improved understanding of major plant stress tolerance mechanisms, the identification of the genes and gene products that are key to improving those mechanisms and means of optimizing those genes through molecular approaches. With a focus on plant physiological and biochemical attributes at both cellular and whole plant levels, this book includes the latest information on crosstalk between the various signaling molecules and quantitative trait locus (QTL). Further, it explores the extension of these mechanisms to breeding approaches, confirming overall understanding and inspiring further research. Written by a team of global experts, and presented in three thematic sections, the book provides insights into physical adaptations, metabolism and pathways, and breeding techniques including CRISPR and conventional approaches to reduce the negative effects of stresses and improve crop yield even under stress conditions. Improving Stress Resilience in Plants: Physiological and Biochemical Basis and Utilization in Breeding is ideal for researchers, academics and advanced students seeking to improve stress tolerance among crop plants and developing key future strategies for sustainable food production. Explores key strategies, including signaling molecules and Quantitative Trait Locus (QTLs) Highlights stress mitigating agents for improved crop yield Provides an integrated and holistic overview, enabling and inspiring further research toward improved food security
Download or read book Molecular Stress Physiology of Plants written by Gyana Ranjan Rout and published by Springer Science & Business Media. This book was released on 2013-02-12 with total page 451 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crop growth and production is dependent on various climatic factors. Both abiotic and biotic stresses have become an integral part of plant growth and development. There are several factors involved in plant stress mechanism. The information in the area of plant growth and molecular mechanism against abiotic and biotic stresses is scattered. The up-to-date information with cited references is provided in this book in an organized way. More emphasis has been given to elaborate the injury and tolerance mechanisms and growth behavior in plants against abiotic and biotic stresses. This book also deals with abiotic and biotic stress tolerance in plants, molecular mechanism of stress resistance of photosynthetic machinery, stress tolerance in plants: special reference to salt stress - a biochemical and physiological adaptation of some Indian halophytes, PSII fluorescence techniques for measurement of drought and high temperature stress signal in crop plants: protocols and applications, salicylic acid: role in plant physiology & stress tolerance, salinity induced genes and molecular basis of salt tolerance mechanism in mangroves, reproductive stage abiotic stress tolerance in cereals, calorimetry and Raman spectrometry to study response of plant to biotic and abiotic stresses, molecular physiology of osmotic stress in plants and mechanisms, functions and toxicity of heavy metals stress in plants, submergence stress tolerance in plants and adoptive mechanism, Brassinosteroid modulated stress responses under temperature stress, stress tolerant in plants: a proteomics approach, Marker-assisted breeding for stress resistance in crop plants, DNA methylation associated epigenetic changes in stress tolerance of plants and role of calcium-mediated CBL-CIPK network in plant mineral nutrition & abiotic stress. Each chapter has been laid out with introduction, up-to-date literature, possible stress mechanism, and applications. Under abiotic stress, plant produces a large quantity of free radicals, which have been elaborated. We hope that this book will be of greater use for the post-graduate students, researchers, physiologist and biotechnologist to sustain the plant growth and development.
Download or read book Bibliography of Agriculture written by and published by . This book was released on 1989-12 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected morphological and agronomic descriptors for the characterization of cassava written by and published by IITA. This book was released on with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Root and Tuber Crops written by J.E. Bradshaw and published by Springer Science & Business Media. This book was released on 2010-09-11 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is important to include Tuber and Root Crops in the Handbook of Plant Breeding. They include starchy staple crops that are of increasing importance for global food security and relief of poverty, important millennium goals for the United Nations. Indeed, 2008 was the UN International Year of the Potato in recognition of this role of the potato as the world’s third most important food crop after wheat and rice. The other major staples are cassava, sweetpotato and yam. Together they occupy about 50 million hectares, with production at 640 million metric tons, of which 70% is in developing countries. In total there are more than 30 species of Root and Tuber Crops grown in the world today. Given the content of other volumes in the series, it makes sense to include sugar and fodder beets; swedes and turnips; and minor root and tuber crops so that the book series is as complete as possible. Like the other volumes in the series, this one will present information on the latest in applied plant breeding using the current advances in the field, from an efficient use of genetic resources to the impact of biotechnology in plant breeding. Seven crop specific chapters are proposed, together with an introduction to this diverse set of plant species. Outstanding scientists for each crop species are proposed as senior authors, who may invite co-authors to contribute part of a chapter. In order to increase the overall acceptance of the volume, balance will be sought with authors from different research groups/countries who will be asked to contribute and collaborate where appropriate. The book should be of interest to researchers in both academic and industrial settings, and in both developed and developing countries, as well as students and teachers of plant breeding. It is currently extremely important to educate and train a new generation of plant breeders given the challenges faced by humankind in producing more food for an expanding global population during a period of environmental (including climate) change.
Download or read book Post harvest Deterioration of Cassava written by J. E. Wenham and published by Food & Agriculture Org.. This book was released on 1995 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Protective Chemical Agents in the Amelioration of Plant Abiotic Stress written by Aryadeep Roychoudhury and published by John Wiley & Sons. This book was released on 2020-07-07 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt: A guide to the chemical agents that protect plants from various environmental stressors Protective Chemical Agents in the Amelioration of Plant Abiotic Stress offers a guide to the diverse chemical agents that have the potential to mitigate different forms of abiotic stresses in plants. Edited by two experts on the topic, the book explores the role of novel chemicals and shows how using such unique chemical agents can tackle the oxidative damages caused by environmental stresses. Exogenous application of different chemical agents or chemical priming of seeds presents opportunities for crop stress management. The use of chemical compounds as protective agents has been found to improve plant tolerance significantly in various crop and non-crop species against a range of different individually applied abiotic stresses by regulating the endogenous levels of the protective agents within plants. This important book: Explores the efficacy of various chemical agents to eliminate abiotic stress Offers a groundbreaking look at the topic and reviews the most recent advances in the field Includes information from noted authorities on the subject Promises to benefit agriculture under stress conditions at the ground level Written for researchers, academicians, and scientists, Protective Chemical Agents in the Amelioration of Plant Abiotic Stress details the wide range of protective chemical agents, their applications, and their intricate biochemical and molecular mechanism of action within the plant systems during adverse situations.
Download or read book Cassava Flour and Starch written by D. Dufour and published by CIAT. This book was released on 1996 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt:
