Induced parthenocarpic cherry tomato fruits did not shown significant differences in l-ascorbate content but showed different pattern in GalLDH and GME expression

Abstract

Parthenocarpy in tomato is often induced by auxins to overcome fertilization problems due to low temperatures. To estimate the effect of this agronomical practice on the physiology and dietary value of cherry tomato fruits we determined l-ascorbic acid, the expression and immunolocalization of galactono 1,4 lactone dehydrogenase and the expression of GDP-mannose 3′,5′-epimerase, key genes in l-ascorbic acid biosynthesis. The levels of l-ascorbic acid did not differ between seeded and parthenocarpic fruits while the relative expression of galactono 1,4 lactone dehydrogenase and GDP-mannose 3′,5′-epimerase gene transcripts showed some significant differences between seeded and parthenocarpic fruits. The galactono 1,4 lactone dehydrogenase immunohistolocalization signal was stronger in the ovules and mature embryos of seed-containing fruits. Our data suggest that although there were differences in the expression of the studied genes and in enzyme localization, these did not cause differences in the l-ascorbic acid content of parthenocarpic fruits produced by auxin application.