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Title: The Phloem as an Arena for Plant Pathogens
Although the phloem is a highly specialized tissue, certain pathogens, including phytoplasmas, spiroplasmas, and viruses, have evolved to access and live in this sequestered and protected environment, causing substantial economic harm. In particular, Candidatus Liberibacter spp. are devastating citrus in many parts of the world. Given that most phloem pathogens are vectored, they are not exposed to applied chemicals and are therefore difficult to control. Furthermore, pathogens use the phloem network to escape mounted defenses. Our review summarizes the current knowledge of phloem anatomy, physiology, and biochemistry relevant to phloem/pathogen interactions. We focus on aspects of anatomy specific to pathogen movement, including sieve plate structure and phloem-specific proteins. Phloem sampling techniques are discussed. Finally, pathogens that cause particular harm to the phloem of crop species are considered in detail.  more » « less
Award ID(s):
1940827
PAR ID:
10393555
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Annual Review of Phytopathology
Volume:
60
Issue:
1
ISSN:
0066-4286
Page Range / eLocation ID:
77 to 96
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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