Phloem: Molecular Cell Biology, Systemic Communication, Biotic Interactions

Phloem has long been recognized for its importance in long–distance transport needed for successful plant growth and development. The advent of new molecular biological methods combined with improved imaging technologies have revolutionized our view of phloem and served as a catalyst to novel phloem research. Phloem: Molecular Cell Biology, Systemic Communication, Biotic Interactions provides an integrative synthesis of our current understanding of this tissue vital to plant development and survival. Phloem: Molecular Cell Biology, Systemic Communication, Biotic Interactions divides its contents into four logical sections. The first section provides a broad overview of phloem biology that will serve as a contextual framework for subsequent sections. The second section looks at the structural and functional components of sieve elements, the sievetube modules. The following sections explore the integral part phloem plays in a variety of long–distance communications that occur within plants. The final section reviews the developing body of research looking at the role of phloem in plant biotic interactions. Providing wide–ranging coverage of the diverse advances in the field of phloem biology and physiology, Phloem: Molecular Cell Biology, Systemic Communication, Biotic Interactions, is an essential reference for anyone interested in the multi–faceted function of this unique plant tissue.

Contributors vii

Section A Introduction 1

Chapter 1 Phloem, the Integrative Avenue 3
Aart J.E. van Bel and Gary A. Thompson

Chapter 2 Cell Biology of Sieve Element Companion CellComplexes 8
Rosemary G. White

Chapter 3 Fundamentals of Phloem Transport Physiology 30
John W. Patrick

Section B Functional Aspects of Structural SE Components61

Chapter 4 Roles of Plasma Membrane Transporters in PhloemFunctions 63
Mechthild Tegeder, Yong–Ling Ruan, and John W. Patrick

Chapter 5 Regulation of Sucrose Carrier Activities 102
Christina K¨uhn

Chapter 6 Cellular Basis of Electrical Potential Waves along thePhloem and Impact of Coincident Ca2+ Fluxes 122
Jens B. Hafke and Aart J.E. van Bel

Chapter 7 Sieve Element Occlusion 141
Michael Knoblauch and Daniel Mullendore

Section C Long–Distance Signaling 155

Chapter 8 Sieve Elements: Puzzling Activities Deciphered throughProteomics Studies 157
Sylvie Dinant and William J. Lucas

Chapter 9 Endogenous RNA Constituents of the Phloem and TheirPossible Roles in Long–Distance Signaling 186
Julia Kehr and Anja Buhtz

Chapter 10 The Effect of Long–Distance Signaling on Development209
David J. Hannapel

Chapter 11 Plant Defense and Long–Distance Signaling in thePhloem 227
Frank Gaupels and A. Corina Vlot

Section D Biotic Interactions with the Phloem 249

Chapter 12 Role of Phloem Metabolites in Plant Defense 251
Jillian M. Hagel, Akpevwe Onoyovwi, Edward C. Yeung, and PeterJ. Facchini

Chapter 13 Viroids and Phloem–Limited Viruses: Unique MolecularProbes of Phloem Biology 271
Lucy R. Stewart, Biao Ding, and Bryce W. Falk

Chapter 14 Phytoplasmas and Spiroplasmas: The PhytopathogenicMollicutes of the Phloem 293
Allyson M. MacLean and Saskia A. Hogenhout

Chapter 15 Breaching the Sieve Element The Role of Salivaas the Molecular Interface between Aphids and the Phloem 310
Torsten Will, James C. Carolan, and Thomas L. Wilkinson

Chapter 16 Behavioral and Molecular–Genetic Basis of Resistanceagainst Phloem–Feeding Insects 328
Linda L. Walling and Gary A. Thompson

Index 353

A color page section appears between pages 40 and 41

Gary A. Thompson is the Associate Dean for Research and Graduate Education, Director of the Pennsylvania Agricultural Experiment Station, and Professor of Plant Sciences in the College of Agricultural Sciences at Pennsylvania State University.

Aart J. E. van Bel is Emeritus Professor and Head of the Department of General Botany and former Director of the Botanical Garden at Justus–Liebig–University.