Stereological estimation of cell wall density of DR12 tomato mutant using three-dimensional confocal imaging.
OBJECTIVE
The cellular structure of fleshy fruits is of interest to study fruit shape, size, mechanical behaviour or sensory texture. The cellular structure is usually not observed in the whole fruit but, instead, in a sample of limited size and volume. It is therefore difficult to extend measurements to the whole fruit and/or to a specific genotype, or to describe the cellular structure heterogeneity within the fruit.


METHODS
An integrated method is presented to describe the cellular structure of the whole fruit from partial three-dimensional (3D) observations, involving the following steps: (1) fruit sampling, (2) 3D image acquisition and processing and (3) measurement and estimation of relevant 3D morphological parameters. This method was applied to characterize DR12 mutant and wild-type tomatoes (Solanum lycopersicum).


RESULTS
The cellular structure was described using the total volume of the pericarp, the surface area of the cell walls and the ratio of cell-wall surface area to pericarp volume, referred to as the cell-wall surface density. The heterogeneity of cellular structure within the fruit was investigated by estimating variations in the cell-wall surface density with distance to the epidermis.


CONCLUSIONS
The DR12 mutant presents a greater pericarp volume and an increase of cell-wall surface density under the epidermis.
Legland
David
D
INRA UMR782 Food Process Engineering and Microbiology, F-78850 Thiverval-Grignon, France. david.legland@grignon.inra.fr
Guillon
Fabienne
F
Kiêu
Kiên
K
Bouchet
Brigitte
B
Devaux
Marie-Françoise
MF
D002473:Cell Wall / Q000378:metabolism*; D005638:Fruit / Q000166:cytology* / Q000235:genetics; D018551:Solanum lycopersicum / Q000166:cytology* / Q000235:genetics; D018613:Microscopy, Confocal; D008954:Models, Biological; D030821:Plants, Genetically Modified / Q000166:cytology* / Q000235:genetics