Plant Water Absorption and Transpiration
Studies in Plant Physiology Series No. 3 Plant Water Absorption and Transpiration S. S. Purohit R. Ranjan Agrobios (India)
Dr. S. S. Purohit Laboratory of Plant Physiology Ex- Head, Department of Botany Dungar College Bikaner (India) Dr. R. Ranjan Department of Botany T. P. Verma College Narkatia Gunj 845 455 (Bihar) AGROBIOS INDIA (2013) All rights reserved. No part of the book or part thereof, including the title of the book, be reprinted in any form or language without the written permission of the author and the publishers. The copyists shall be prosecuted ISBN: 978-81-7754-167-0 Published by: Dr. Updesh Purohit for Agrobios (India), Jodhpur Laser typeset at: Yeshee Computers, Jodhpur Cover Design by: Reena Printed at: Babloo Offset, Jodhpur
Preface Water absorption by plants and its subsequent translocation to leaves are passive processes, which do not consume any metabolic energy generated by plants. The absorbed water is evaporated by plants mainly through stomata. This loss of water from the aerial parts of the plant is termed as transpiration and occurs almost entirely through the leaves. The loss of water from a leaf surface takes place mainly through the stomata. The book presents an over all description of eco-physiological aspects of water loss by plants and includes chapters like, Plant water absorption and transpiration, Guard cells: structure and development, The response of stomata to environmental factors, Stomatal movements: endogenous control, The role of ion fluxes in stomatal movements, Carbon metabolism in guard cells, Mechanism and control of stomatal movement, Signal transduction and stomatal movement, Stomatal movement, water relations and plant growth regulators, Carbon dioxide enrichment of the atmosphere, stomata and water economy of plants, Antitranspirants. In the end Laboratory studies with stomata has also been included. We are thankful to various sources from where literature has been collected and cited.
Thanks are also due to Dr. Updesh Purohit, Agrobios (India) who too pains to bring out the book in record time. Authors
Contents 1 PLANT WATER ABSORPTION AND TRANSPIRATION... 1 Absorption of Water... 2 Transpiration... 6 Stomatal Transpiration... 7 Cuticular Transpiration... 7 Lenticular Transpiration... 8 The Nature of Transpiration... 9 Evapotranspiration (ET)... 9 The Transpiration Path... 9 The Non stomatal External Diffusion Path... 10 The Non stomatal Internal Diffusion Path... 10 Relative Magnitude of the Parts of the Diffusion Path... 10 2 GUARD CELLS: STRUCTURE AND DEVELOPMENT... 12 The Origins and Distribution of Stomata... 12 The Role of Stomata... 12 Structure of Stomata... 15 Number and Density of Stomata... 17 Internal Air of the Leaf... 17
Development of Stomatal Complex... 17 Stomata: Elliptic type... 17 Stomata: Graminaceous type... 18 Development... 19 Development of Stomatal Complexes... 19 Agenous development... 19 Mesogenous development... 19 Perigenous development... 19 Number, Shape and Distribution of Subsidiary Cells... 21 Organelles of Guard Cells... 21 Plastids of Guards Cells... 21 Nuclei of Guard Cells... 22 Mitochondria of Guard Cell... 22 Spherosomes in Guard Cells... 23 Other Inclusions of Guard Cells... 23 Development of Guard Cells... 23 Thickening in Guard Cells... 23 Stoma Formation... 24 Elliptic guard cells... 24 Graminaceous gurad cells... 24 Stomatal Mechanics... 24 Plasmodesmata and Ectodesmata... 27 Substomatal Ion adsorbent Bodies... 28 3 THE RESPONSE OF STOMATA TO ENVIRONMENTAL FACTORS... 29 Light... 29 Steady State Opening... 30 Night opening... 31 Midday closure... 31 Photoperiod Requirement... 31 Blue Light... 32 Light Responses... 33
Carbon dioxide... 33 Temperature... 34 Water Stress... 35 Air Humidity... 37 Ozone and Stomatal Behaviour... 38 4 STOMATAL MOVEMENTS: ENDOGENOUS CONTROL... 42 Endogenous Rhythms... 43 Endogenous Nature of the Rhythm... 43 Diagnostic criteria of endogenous and circadian... 44 Molecular Mechanisms of Circadian Rhythms... 44 Period and Amplitude... 45 Rhythms in Continuous Light and Darkness... 46 Significance of Circadian Rhythms Under Natural Conditions... 49 Stomatal Behaviour of Succulents... 50 Circadian Rhythms and Diurnal Metabolic Rhythms in Guard Cells... 50 Starch sugar Hypothesis... 51 Dark Fixation Hypothesis... 51 Other Cyclic Variations in Stomatal Aperture... 52 5 THE ROLE OF ION FLUXES IN STOMATAL MOVEMENTS... 53 The Role of Potassium in Stomatal Movements... 54 The Role of K +, Cl and Metabolic Energy... 59 Stomata: Role of ATP... 61 Stomata: Role of Mitochondria... 62 Stomata: Involvement of Blue Light... 63 The Chemiosmotic Hypothesis... 63 Phytochrome Effects in K + Fluxes... 64 Stomata: The Role of Calcium Ion... 65 Apoplastic Calcium Ions... 65 Stomata: Ion Channels... 67
Plant Water Absorption and Transpiration Publisher : Agrobios Publications ISBN : 978817754 1670 Author : S S Purohit And R Ranjan Type the URL : http://www.kopykitab.com/product/6859 Get this ebook