Download or read book Physiology of Low Temperature Modulated Postharvest Needle Senescence and Abscission in Balsam Fir Abies Balsamea L written by Arumugam Thiagarajan and published by . This book was released on 2012 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le sapin baumier (Abies balsamea L.), espèce favorite des producteurs d'arbres et de couronnes de Noël dans les provinces de l'Atlantique, est victime de chutes d'aiguilles sévères (abscission prématurée) après la récolte. Une série d'expériences ont été réalisées pour : (i) déterminer le rôle des racines, (ii) identifier la température et le temps d'exposition optimums permettant d'augmenter la durée de rétention des aiguilles (DRA) en post-récolte; (iii) déterminer et caractériser les changements de concentration en phytohormones en réponse à un traitement de basse température (BT); (iv) élucider l'effet interactif des facteurs génotypiques et environnementaux sur la DRA post-récolte; et (v) investiguer les dynamiques temporelles de l'accumulation de l'acide abscissique (ABA) induite par les basses températures et évaluer l'effet de l'ABA sur la DRA. Les semis de sapin baumier soumis à 5°C durant au moins 6 h ont présenté une DRA supérieure de 11 jours et la présence de racines a eu un effet synergique retardant l'abscission des aiguilles. Lorsque soumis à 5°C durant 48 h, la concentration foliaire en ABA des semis a augmenté de 2,5 fois (2007 ng g−1 DW) et l'acide gibbérellique GA44 a diminué de 3,5 fois (9,85 ng g−1 DW). Le traitement BT n'a eu aucun effet sur les phytohormones dans les racines. Parmi les deux génotypes (AB-NSD-184 et AB-NSD-004) étudiés dans le verger Debert en Nouvelle-Ecosse, une corrélation négative fut observée entre la DRA post-récolte des branches échantillonnées et les facteurs climatiques choisis (moyenne des heures de photopériode quotidienne (PP) et moyenne des températures maximales quotidiennes) (R2=0,75; P=0,001) ainsi qu'avec les concentrations foliaires en ABA (R2=0,38; P=0,001) chez le génotype ABNSD- 184 seulement. Une DRA maximale de 180 jours et minimale de 41 jours furent observées respectivement en octobre et juin. Les conditions environnementales ont fortement modulé les effets du traitement BT sur la RDA post-récolte. La déshydratation a accéléré l'abscission des aiguilles, et le traitement BT appliqué sous conditions lumineuses a compensé pour les effets de la déshydratation et a augmenté la RDA de 30 jours. De tels avantages n'ont pas été observés lorsque le traitement fut appliqué dans l'obscurité. Les bénéfices physiologiques découlant du traitement BT ne furent présents que sous un faible déficit de pression de vapeur (DPV; 0,87 kPa). Sous DPV élevé ( 1,30 kPa), BT a diminué la RDA de 35% (45 jours), réduit de moitié la teneur en eau relative des aiguilles, et augmenté de 4 fois le potentiel hydrique du xylème. Les changements temporels de la concentration foliaire en ABA ont différé entre les génotypes et I l l l'ABA a augmenté avec le temps après récolte. L'apport d'ABA via le xylème à des concentrations > 95 uM a provoqué l'abscission des aiguilles. Cependant, une concentration entre 2,5 et 7,5 uM d'ABA acheminée via le xylème durant 15 jours a prolongé la DRA de 20 jours. Ni les concentrations élevées d'ABA (12,5 uM), ni l'inhibition de la synthèse de l'ABA n'ont augmenté la DRA. Les bénéfices du traitement BT sur la durée de rétention des aiguilles implique des changements de l'ABA foliaire et cette réponse a varié en fonction des génotypes et des conditions environnementales.
Download or read book Plant Organ Abscission From Models to Crops written by Timothy J. Tranbarger and published by Frontiers Media SA. This book was released on 2017-11-22 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plant organ abscission is a developmental process regulated by the environment, stress, pathogens and the physiological status of the plant. In particular, seed and fruit abscission play an important role in seed dispersion and plant reproductive success and are common domestication traits with important agronomic consequences for many crop species. Indeed, in natural populations, shedding of the seed or fruit at the correct time is essential for reproductive success, while for crop species the premature or lack of abscission may be either beneficial or detrimental to crop productivity. The use of model plants, in particular Arabidopsis and tomato, have led to major advances in our understanding of the molecular and cellular mechanisms underlying organ abscission, and now many workers pursue the translation of these advances to crop species. Organ abscission involves specialized cell layers called the abscission zone (AZ), where abscission signals are perceived and cell separation takes place for the organ to be shed. A general model for plant organ abscission includes (1) the differentiation of the AZ, (2) the acquisition of AZ cells to become competent to respond to various abscission signals, (3) response to signals and the activation of the molecular and cellular processes that lead to cell separation in the AZ and (4) the post-abscission events related to protection of exposed cells after the organ has been shed. While this simple four-phase framework is helpful to describe the abscission process, the exact mechanisms of each stage, the differences between organ types and amongst diverse species, and in response to different abscission inducing signals are far from elucidated. For an organ to be shed, AZ cells must transduce a multitude of both endogenous and exogenous signals that lead to transcriptional and cellular and ultimately cell wall modifications necessary for adjacent cells to separate. How these key processes have been adapted during evolution to allow for organ abscission to take place in different locations and under different conditions is unknown. The aim of the current proposal is to present and be able to compare recent results on our understanding of organ abscission from model and crop species, and to provide a basis to understand both the evolution of abscission in plants and the translation of advances with model plants for applications in crop species.
Download or read book Canadian Journal of Forest Research written by and published by . This book was released on 2014-10 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The RELATIONSHIP BETWEEN PECTINASE AND CELLULASE AND POST HARVEST NEEDLE ABSCISSION IN BALSAM FIR Abies Balsamea L written by Jingyi Wang and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Post-harvest needle abscission is a major challenge for the Christmas tree industry in Atlantic Canada. To further elucidate the physiological basis of needle loss in Balsam fir, experiments were conducted to investigate the possible link between certain hydrolytic enzymes and post-harvest needle abscission in balsam fir. This study focussed on the role of enzymes, pectinase and cellulase, in post-harvest needle abscission. Following harvest, cumulative cellulase activity increased over time prior to needle loss on both high and low needle retention duration (NRD) clones. Total cellulase activity of low NRD clone was much higher than that of high NRD clone. Pectinase does not affect needle abscission in this study. If cellulase activity is linked to post-harvest needle abscission, then inhibiting cellulase enzyme would reduce needle loss. Pre-treating branches with 2.5g 1-methylcyclopropene (1-MCP) enhanced needle retention.
Download or read book PHYSIOLOGY OF MECHANICAL STRESS INDUCED NEEDLE LOSS IN POSTHARVEST BALSAM FIR ABIES BALSAMEA L written by Ernest Korankye and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The NATURE AND DYNAMICS OF CHANGES IN LIPIDS AND FATTY ACIDS DURING POSTHARVEST NEEDLE ABSCISSION THEIR ROLE IN COLD ACCLIMATION ULTRA STRUCTURAL CHANGES AND NEEDLE ABSCISSION RESISTANCE IN BALSAM FIR ABIES BALSAMEA L written by Gaye MacDonald and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physiological Significance of Ethylene in Needle Abscission of Root detached Balsam Fir Abies Balsamea L Mill written by Mason T. (Mason Thane) MacDonald and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'abscission prématurée des aiguilles constitue un problème majeur pour l'industrie de l'arbre de Noël dans les provinces Atlantiques du Canada. Les objectifs de cette étude étaient donc de déterminer: 1) l'effet de l'éthylène endogène et exogène sur l'abscission des aiguilles, 2) l'effet de l'utilisation d'inhibiteurs de l'activité de l'éthylène sur l'abscission des aiguilles, 3) l'activité des cellulases associées à l'éthylène et l'abscission des aiguilles, 4) l'interaction entre l'éthylène et la variabilité génotypique, et 5) l'effet de l'éthylène sous des conditions de perte d'eau réduite. Nos résultats ont démontré que l'éthylène est impliqué comme signal d'abscission pour les aiguilles du sapin baumier. Il a été constaté que l'évolution de l'éthylène endogène a augmenté à des taux variant de 10,5 à 20,0 (j.L-g"lh"' suivie immédiatement de l'abscission complète des aiguilles. Selon la concentration utilisée, l'apport exogène d'ethylene a réduit la durée de rétention des aiguilles de 30 à 70%. En absence d'éthylène exogène, l'inhibition de l'éthylène avec AVG ou 1-MCP a retardé respectivement l'abscission des aiguilles de 113 et 73%. D'autre part, l'éthylène a stimulé l'activité des cellulases. Les branches ne démontrant aucun signe d'abscission ont eu une activité cellulase de 0,4 unité alors que les branches induites par l'éthylène exogène et endogène ont eu une activité respective de 4,6 et 3,1 unités. Les génotypes ayant une faible durée de rétention de leurs aiguilles ont libéré 50% plus d'éthylène et ont réagi à l'éthylène exogène plus tôt que les génotypes possédant une durée de rétention élevée de leurs aiguilles. Enfin, le contrôle de la perte d'eau a significativement retardé l'abscission induite par l'éthylène. Ainsi, l'exposition des branches à 90% d'humidité ou à une température de 5°C a diminué la perte d'eau, l'évolution de l'éthylène et l'abscission des aiguilles. Le stockage des branches à une humidité de 90% a été particulièrement efficace augmentant de plus de 3 fois la durée de rétention des aiguilles. Il est ainsi suggéré que le sapin baumier réagisse à de faibles stress hydriques en libérant de l'éthylène. Une exposition de courte durée à l'éthylène est toutefois bénéfique alors qu'une exposition continuelle stimule les enzymes hydrolytiques qui culminent en l'abscission des aiguilles.
Download or read book Determining the Link Between Certain Hydraulic Properties and Postharvest Needle Abscission in Balsam Fir Abies Balsamea L Mill written by Robin MacInnes and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determining the Relationship Between Needle Nutrition and Post harvest Needle Retention in Balsam Fir Abies Balsamea L Mill written by Melissa Georgeson and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quality of Ornamental Crops Effect of Genotype Preharvest and Improved Production Chains on Quality Attributes of Ornamental Crops volume II written by Patricia Duarte De Oliveira Paiva and published by Frontiers Media SA. This book was released on 2024-08-23 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Research Topic is part of the Quality of Ornamental Crops: Effect of Genotype, Preharvest, and Improved Production Chains on Quality Attributes of Ornamental Crops series. Acceptance of ornamental crops depends on a large extent on flower color, fragrance and shape. Flower number and size, uniformity of blooming, as well as plant shape, patterning and color determine the crop's appeal. Vase life, or postharvest quality retention, involves preserving specific features such as flower color and scent. In addition, leaf and stem color, plant shape, and development should occur within particular ranges, while pests and diseases must be absent. Thus, genotype, growing conditions, harvest practices and postharvest conditions contribute to maintaining quality after harvest.
Download or read book Plant Lipid Metabolism written by J.C. Kader and published by Springer Science & Business Media. This book was released on 2013-04-18 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt: A collection of papers that comprehensively describe the major areas of research on lipid metabolism of plants. State-of-the-art knowledge about research on fatty acid and glycerolipid biosynthesis, isoprenoid metabolism, membrane structure and organization, lipid oxidation and degradation, lipids as intracellular and extracellular messengers, lipids and environment, oil seeds and gene technology is reviewed. The different topics covered show that modern tools of plant cellular and molecular biology, as well as molecular genetics, have been recently used to characterize several key enzymes of plant lipid metabolism (in particular, desaturases, thioesterases, fatty acid synthetase) and to isolate corresponding cDNAs and genomic clones, allowing the use of genetic engineering methods to modify the composition of membranes or storage lipids. These findings open fascinating perspectives, both for establishing the roles of lipids in membrane function and intracellular signalling and for adapting the composition of seed oil to the industrial needs. This book will be a good reference source for research scientists, advanced students and industrialists wishing to follow the considerable progress made in recent years on plant lipid metabolism and to envision the new opportunities offered by genetic engineering for the development of novel oil seeds.
Download or read book Physiology of Woody Plants written by Stephen G. Pallardy and published by Academic Press. This book was released on 2010-07-20 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: Woody plants such as trees have a significant economic and climatic influence on global economies and ecologies. This completely revised classic book is an up-to-date synthesis of the intensive research devoted to woody plants published in the second edition, with additional important aspects from the authors' previous book, Growth Control in Woody Plants. Intended primarily as a reference for researchers, the interdisciplinary nature of the book makes it useful to a broad range of scientists and researchers from agroforesters, agronomists, and arborists to plant pathologists and soil scientists. This third edition provides crutial updates to many chapters, including: responses of plants to elevated CO2; the process and regulation of cambial growth; photoinhibition and photoprotection of photosynthesis; nitrogen metabolism and internal recycling, and more. Revised chapters focus on emerging discoveries of the patterns and processes of woody plant physiology.* The only book to provide recommendations for the use of specific management practices and experimental procedures and equipment*Updated coverage of nearly all topics of interest to woody plant physiologists* Extensive revisions of chapters relating to key processes in growth, photosynthesis, and water relations* More than 500 new references * Examples of molecular-level evidence incorporated in discussion of the role of expansion proteins in plant growth; mechanism of ATP production by coupling factor in photosynthesis; the role of cellulose synthase in cell wall construction; structure-function relationships for aquaporin proteins
Download or read book Ane s Encyclopedic Dictionary of General Applied Entomology written by Manjit S Dhooria and published by Springer Science & Business Media. This book was released on 2009-01-20 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keeping the requirements of teachers and researchers in mind, this encyclopedic dictionary presents the terminology in entomology and pest management in the most authentic and comprehensive way. It also includes terms related to the close relatives of insects, such as mites and ticks and some other organisms which are pests of crops.
Download or read book Horticulture Plants for People and Places Volume 2 written by Geoffrey R. Dixon and published by Springer. This book was released on 2014-06-10 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Trilogy explains “What is Horticulture?”. Volume two of Horticulture: Plants for People and Places analyses in depth the scientific, managerial and ecological concepts which underpin Environmental Horticulture. Chapters describe: Horticulture and the Environment, Woody Ornamentals, Herbs and Pharmaceuticals, Urban Greening, Rural Trees, Urban Trees, Turfgrass Science, Interior and External Landscaping, Biodiversity, Climate Change and Organic Production. Each is written by leading international experts. Sustainable use of resources and careful conservation are critically essential for the continuation of life on this Planet. Achieving this is where horticulture, natural flora and fauna and the environment interact in achieving sustainable development. Horticulture is the fundamental partner of ecological and environmental science and provides an understanding of eco-system services. Live plant networks are essential for rural and urban life. They are integral parts of natural communities, the context of historic and modern architecture and a means for rejuvenating cities and uniting communities. Plants provide urban, peri-urban and rural employment, business and tourism opportunities, leisure, rest and relaxation. These facets of Environmental Horticulture are clearly described in this book.
Download or read book The Plant Plasma Membrane written by Angus S. Murphy and published by Springer Science & Business Media. This book was released on 2010-11-11 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: In plant cells, the plasma membrane is a highly elaborated structure that functions as the point of exchange with adjoining cells, cell walls and the external environment. Transactions at the plasma membrane include uptake of water and essential mineral nutrients, gas exchange, movement of metabolites, transport and perception of signaling molecules, and initial responses to external biota. Selective transporters control the rates and direction of small molecule movement across the membrane barrier and manipulate the turgor that maintains plant form and drives plant cell expansion. The plasma membrane provides an environment in which molecular and macromolecular interactions are enhanced by the clustering of proteins in oligimeric complexes for more efficient retention of biosynthetic intermediates, and by the anchoring of protein complexes to promote regulatory interactions. The coupling of signal perception at the membrane surface with intracellular second messengers also involves transduction across the plasma membrane. Finally, the generation and ordering of the external cell walls involves processes mediated at the plant cell surface by the plasma membrane. This volume is divided into three sections. The first section describes the basic mechanisms that regulate all plasma membrane functions. The second describes plasma membrane transport activity. The final section of the book describes signaling interactions at the plasma membrane. These topics are given a unique treatment in this volume, as the discussions are restricted to the plasma membrane itself as much as possible. A more complete knowledge of the plasma membrane’s structure and function is essential to current efforts to increase the sustainability of agricultural production of food, fiber, and fuel crops.
Download or read book Lipid signaling in plants written by Xuemin Wang and published by Frontiers E-books. This book was released on 2013-07-30 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cell membranes are the initial and focal sites of stimulus perception and signal transduction. Membrane lipids are rich sources for the production of signaling messengers that mediate plant growth, development, and response to nutrient status and stresses. In recent years, substantial progress has been made toward understanding lipid signaling in plants, but many fundamental questions remain: What lipids are signaling messengers or mediators in plants? How are the signaling lipids produced and metabolized? In what plant cellular and physiological processes are various lipid mediators involved? How do they carry out their signaling functions? How do lipid signaling networks contribute to modulating plant growth, development, and responses to hormones and stresses? In this Research Topic issue, we invite the broad plant community to address the above questions.Cell membranes are the initial and focal sites of stimulus perception and signal transduction. Membrane lipids are rich sources for the production of signaling messengers that mediate plant growth, development, and response to nutrient status and stresses. In recent years, substantial progress has been made toward understanding lipid signaling in plants, but many fundamental questions remain: What lipids are signaling messengers or mediators in plants? How are the signaling lipids produced and metabolized? In what plant cellular and physiological processes are various lipid mediators involved? How do they carry out their signaling functions? How do lipid signaling networks contribute to modulating plant growth, development, and responses to hormones and stresses? In this Research Topic issue, we invite the broad plant community to address the above questions.
Download or read book Food Proteins and Peptides Emerging Biofunctions Food and Biomaterial Applications written by Chibuike C. Udenigwe and published by Royal Society of Chemistry. This book was released on 2021-06-09 with total page 537 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the chemistry of food proteins and peptides and their relationship with nutritional, functional, and health applications. Bringing together authorities in the field, it provides a comprehensive discussion focused on fundamental chemistries and mechanisms underpinning the structure-function relationships of food proteins and peptides. The functional and bioactive properties hinge on their structural features such as amino acid sequence, molecular size, hydrophobicity, hydrophilicity, and net charges. The book includes coverage of advances in the nutritional and health applications of protein and peptide modifications; novel applications of food proteins and peptides in the development of edible functional biomaterials; advances in the use of proteomics and peptidomics for food proteins and peptide analysis (foodomics); and the relevance of food protein and peptide chemistries in policy and regulation. Research into the fundamental chemistries behind the functional, health and nutritional benefits is burgeoning and has gained the interest of scientists, the industry, regulatory agencies, and consumers. This book fills the knowledge gap providing an excellent source of information for researchers, instructors, students, food and nutrition industry, and policy makers.
