Suberization of tomato (Lycopersicon esculentum) locule tissue

Abstract

1985. Suberization of tomato (Lycopersicon esculentum) locule tissue. Can. J. Bot. 63: 2177-2180.It was demonstrated by electron microscopy that wounded and cultured tomato fruit outer placental (locule) tissue generated lamellated (secondary) walls. BF-, -methanol depolymerization of an extract from these walls and its chromatographic analysis showed the presence of the polymer suberin in the tissue adjacent to the wound after 7 days in culture. Quantitative studies using Iatroscan thin-layer chromatography coupled with flame ionization detection showed close similarities between the aliphatics of this wound suberin (which constituted 70% of the total monomers recovered) and that generated by protoplasts isolated from the same tissue, particularly among the monofunctional products, but some striking differences among the difunctional products. It is proposed that the results support the concept that protoplast isolation elicits a wound response similar to that elicited by mechanical wounding of the mother tissue, but that the physiological conditions obtained during protoplast isolation and culture result in a modification of this response. RAO, G. S. R. L., J. H. M. WILLISON et W. M. N. RATNAYAKE. 1985. Suberization of tomato (Lycopersicon esculentum)locule tissue. Can. J. Bot. 63: 2177-2180. L'on a dCmontrC par la microscopic Clectronique chez des fruits de tomate blessCs, en culture in vitro, que le placenta externe (locule) produit des parois secondaires. La dCpolymCrisation par le BS-mCthanol d'un extrait de ces parois et l'analyse chromatographique de cet extrait rCvklent la presence de subkrine dans le tissu adjacent B la blessure aprks 7 jours de culture. Des Ctudes quantitatives utilisant la chromatographie sur couche mince (Iatroscan) couplCe B la detection par l'ionisation de flamme ont montri de fortes ressemblances entre les composCs aliphatiques de cette subCrine (elle constitue 70% des monomkres totaux recouvrCs) et ceux produits par des protoplastes isolCs des mCmes tissus, en particulier au niveau des produits non fonctionnels, mais certaines diffkrences frappantes entre les produits disfonctionnels. On propose que les rCsultats appuient le concept selon lequel l'isolation des protoplastes provoque une rCponse aux blessures similaire B celle des blessures micaniques du tissu maternel. Cependant, les conditions physiologiques au cours de l'isolation et de la culture des protoplastes modifient cette rCponse.[Traduit par le journal]