Use this URL to cite or link to this record in EThOS:
Title: Biosilicification in Oryza sativa and other plants
Author: Stokes, Ian
ISNI:       0000 0004 5990 4266
Awarding Body: Keele University
Current Institution: Keele University
Date of Award: 2016
Availability of Full Text:
Access from EThOS:
Access from Institution:
Rice (Oryza sativa) is well known as a biosilicifier though the mechanisms which underlie the silica deposition in them are still relatively unknown. Silica deposits in rice were imaged through various complementary techniques including PDMPO staining and fluorescence microscopy, scanning electron microscopy, micro-particle induced X-ray emission and low-energy X-ray fluorescence. These techniques showed silica deposition throughout all expected sites of silica deposition, as well as revealing novel areas of silica deposition in the xylem, a region not usually considered to be a zone of silicification despite its known role in transporting silicic acid. Silicon was found to be co-localised with aluminium at the silica cells through the use of low-energy X-ray fluorescence. This is, to the best of our knowledge, the first evidence of silicon/aluminium colocalisation in rice leaves. The link between the hemicellulose callose and silicification was investigated, with aniline blue and immunofluorescence staining revealing numerous sites of callose deposition in rice leaf tissue, all of which matched with known areas of silica deposition. It was demonstrated that silicic acid uptake in rice does occur at a rate which would require active transport through the use of a simple experiment where the silicic acid content of solutions with rice plants growing in them were measured over time. Silicification was studied in developing rice seedlings using PDMPO staining and fluorescence microscopy to image structures from different developmental stages of seedlings. Silicification was found to occur at all stages of development, with evidence of silicification of precursor leaf tissue inside ungerminated seeds. The implications of these findings were discussed and the possibility that silicon may be maintained in a form other than solid silica in certain areas of rice plants was put forward.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: QK Botany