Effects of the <Emphasis Type="Italic">Papaya meleira virus</Emphasis> on papaya latex structure and composition |
| |
Authors: | Silas P Rodrigues Maura Da Cunha José A Ventura Patricia Machado Bueno Fernandes |
| |
Institution: | 1.Núcleo de Biotecnologia,Universidade Federal do Espírito Santo,Vitória,Brazil;2.Instituto Capixaba de Pesquisa Assistência Técnica e Extens?o Rural,Vitória,Brazil;3.Instituto de Biociências e Biotecnologia,Universidade Estadual do Norte Fluminense,Campos dos Goytacazes,Brazil |
| |
Abstract: | Spontaneous latex exudation is the main symptom of papaya sticky (meleira) disease caused by the Papaya meleira virus (PMeV), a double-stranded RNA (dsRNA) virus. This paper describes different effects of PMeV on papaya latex. Latex samples
were subjected to different histochemical tests to evaluate their chemical composition. Additionally, the integrity of the
latex particles was assessed by transmission and scanning electron microscopy analysis. Biochemical and micro- and macro-element
measurements were performed. PMeV dsRNA extraction was performed to evaluate the interaction of the virus with the latex particles.
Sticky diseased latex was positive for alkaloid biosynthesis and showed an accumulation of calcium oxalate crystals. PMeV
also increased H2O2 synthesis within sticky diseased laticifers. The protein, sugar and water levels were altered, probably due to chemical changes.
The morphology of the latex particles was further altered; PMeV particles seemed to be bound to the latex particles. The alkaloid
and H2O2 biosynthesis in the papaya laticifers indicate a papaya defense response against PMeV. However, such efforts failed, as the
virus affected the plant latex. The effects described here suggest some advantages of the infection process, including facilitating
the movement of the virus within the papaya plant. |
| |
Keywords: | Carica papaya Latex Laticifers Meleira Papaya meleira virus Papaya sticky disease |
本文献已被 SpringerLink 等数据库收录! |
|