Open AccessIdentification of sieve elements and companion cell protoplasts by a combination of brightfield and fluorescence microscopy
Author(s) -
Kaur Prabhjot,
Gonzalez Pedro,
Dutt Manjul,
Etxeberria Ed
Publication year - 2018
Publication title -
applications in plant sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.64
H-Index - 23
ISSN - 2168-0450
DOI - 10.1002/aps3.1179
Subject(s) - phloem , biology , organelle , sieve tube element , protoplast , vacuole , autofluorescence , cytoplasm , fluorescence microscope , chloroplast , biophysics , nucleus , microbiology and biotechnology , population , mitochondrion , botany , fluorescence , biochemistry , physics , demography , quantum mechanics , sociology , gene
Premise of the Study Phloem‐limited diseases are becoming increasingly pervasive, threatening the existence of crops worldwide. Studies of phloem diseases are complicated by the inaccessibility of the phloem tissue. Phloem cells are located deep inside the plant body, are interspersed with other cell types, are among the smallest cells in the plant kingdom, and make up a small percentage of the total cell population in a plant. These properties make phloem cells difficult to investigate. Methods We used leaf midrib protoplasts and a combination of organelle‐specific dyes including Neutral Red (acidic compartments), MitoTracker Green (mitochondria), Hoechst 3342 (nucleus), and chloroplast autofluorescence. We examined the protoplasts under light and fluorescence microscopy. Results When observed using brightfield and fluorescence microscopy, sieve element protoplasts were distinguished by the lack of vacuole and a nucleus, and by containing various mitochondria. Companion cells showed a dense cytoplasm and various small vacuoles. They also revealed their characteristic large nucleus and abundant mitochondria. Discussion We present evidence that a combination of organelle‐specific dyes and autofluorescence allows for the identification of sieve elements and companion cell protoplasts from citrus leaf tissue.