Differential accumulation of flavonoids by tomato (Solanum lycopersicum) fruits tissues during maturation and ripening

Objective: Little is known about physiological functions of flavonoids, specifically in the course of maturation and ripening of fruits. Spatiotemporal changes in the levels of flavonoids were investigated in the present study with focus on possible functional differentiation of individual compounds as related to the maturation or ripening of tomato fruits.Methodology and results: The contents of flavonoids in different tissues of tomato fruits at increasing maturation and ripening stages were determined using high performance liquid chromatography – mass spectrometry. The levels of eriodictyol, kaempferol-glc-rhamnose, naringenin, naringenin-chalcone-hexose and quercetin-glc-rhamnose remained almost constant in the mesocarp and endocarp. The contents of eriodictyol, dicaffeoylquinic acid, naringenin and naringenin-chalcone-hexose significantly (P<0.05) increased in the epicarp from ripening stage 1 onwards. The concentration of dicaffeoyquinic acid increased significantly (P<0.05) in both the mesocarp and endocarp of tomato fruits from ripening stage 1 onwards. Gradual increases in the levels of caffeic-acid-hexose and caffeoylquinic acid in the epicarp and endocarp of tomatoes were observed. The level of kaempferol-glc-rhamnose decreased gradually in the epicarp. The content of quercetin-glc-rhamnose was always higher in the epicarp than in the mesocarp and endocarp. The results obtained indicated increases in the endogenous levels of some flavonoids in the epicarp (especially naringenin) with the onset of the ripening. There was also a gradual decrease and increase in the levels of respectively kaempferol-glc-rhamnose in the epicarp and caffeic-acid-hexose in the endocarp. Thus, an increase in the level of naringenin in the epicarp could be considered as physiological index for the ripening whereas high levels of kaempferol-glc-rhamnose in the epicarp and caffeic-acidhexose in the endocarp could serve as characteristic traits for respectively immature and red-ripe state of tomato fruits. On the whole, the results point to specific roles of individual flavonoids as some might be involved in the regulation of either the maturation or ripening of tomato fruits whereas others might functionally be needed throughout both processes, and that there would be a specialization of tissues in the synthesis of specific types of flavonoids.Conclusions and application findings: The degree of accumulation of flavonoids in tomato varied according to the nature of the tissue, and the maturation and ripening stages. It is hypothesized that an increase in the contents of naringenin and caffeic-acid-hexose may be part of natural mechanisms by which ripe tomato fruits prevent the over ripening when they are still attached to the mother plant. Consequently, the enhancement of the levels of these compounds by genetic engineering, conventional breeding or cultural practices could be a novel strategy for extending the shelf-life of tomato fruits. Key words: Naringenin, caffeic-acid-hexose, kaempferol-glc-rhamnose, fruit maturation, ripening, Solanum lycopersicum L. cv Balkonsta

Spatiotemporal changes in the Content and Metabolism of 9, 12, 13 – Trihydorxy-10(E)-Octadecenoic Acid in Tomato (Solanum Lycopersicum L. CV Balkonsar) fruits

In a previous study, we showed that 9,12,13-trihydroxy-10(E)-octadecenoic acid which is probably involved in plant defense responses is synthesized in tomato fruits and subjected to metabolism. Its catabolism or conversion was thus further characterized. The endogenous level of 9,12,13-trihydroxy-10(E)-octadecenoic acid decreased in the mesocarp and endocarp during the maturation of tomato fruits. The level of this trihydroxy fatty acid in the epicarp declined till the mature-green stage and then increased during the colour change. Injection of buffered solutions of unlabeled 9,12,13-trihydroxy-10(E)-octadecenoic acid into two weeks old fruits while they were still attached to the plants led to the alteration of contents of ten metabolites. After the infiltration of buffered solutions of isotopically labeled 9,12,13-trihydroxy-10(E)-octadecenoic acid into green unripe tomato fruits which were still attached to the plant, the highest radioactivity was found in compounds much more polar than 9,12,13-trihydroxy-10(E)-octadecenoic acid and whose signals in HPLC-UV-chromatogram coincided with the citric acid peak. These results indicated that 9,12,13-trihydroxy-10(E)-octadecenoic acid could be implicated in the control of tomato fruit maturation and β-oxidation might be one of its degradation pathwaysKeywords: Ethylene production, fruit maturation, ripening, β-oxidation, pinellic acid, Solanum lycopersicum L. cv Balkonsta

Influence of calcium and magnesium based fertilizers on fungal diseases, plant growth parameters and fruit quality of three varieties of tomato (Solanum lycopersicum)

Notwithstanding the important roles of calcium and magnesium ions in plant growth and development,the use of fertilizers containing them is not yet a common agricultural practice in Cameroon. Such fertilizers were applied on the soil and leaves of three most cultivated varieties of tomato in the Western Highlands of Cameroon. The effects of these treatments on plant health, growth, development, and yield and fruit quality were determined. The combination of soil application of calcium nitrate and foliar sprays of fertilizer containing calcium (T1) led to significant reductions of the severity and incidence of Phytophthora infestans and Septoria lycopersici on leaves of Rio Grande and Rio de Grenier tomato plants seven days after the first foliar application (d.a.f.a) of liquid fertilizers. At the same time significant reductions in the incidence and severity of S. lycopersici were observed on leaves of Roma plants previously treated with a solution of the fertilizer containing magnesium (T2) or simultaneously treated with calcium and magnesium solutions (T3). Twenty-one d.a.f.a there were reductions in the severity of Alternaria solani on leaves of Rio Grande, Rio de Grenier and Roma plants that previously received T3. Applications of T3 also led to the reduction of the incidence and severity of Fulvia fulva on the leaves of both Rio Grande and Rio de Grenier 21 d.a.f.a. T3 was very effective in enhancing the growth in length and yield of Rio Grande and Rio de Grenier plants. The green-life of fruits produced by these two tomato varieties that received T1 was respectively 10 and 6 days longer than that of control fruits. T2 prolonged the shelf-life of fruits from those varieties by 4 and 12 days respectively. On the whole, Rio Grande and Rio de Grenier plant were the tomato varieties whose health, growth, development, yield and fruit quality parameters were the most positively affected by treatments with fertilizers containing calcium oder magnesium. Roma tomato plants were affected to a lesser extent by these treatments. These results could be interpreted in terms of a temporal shift in the resistance of tomato plants to P. infestans and S. lycopersici on the one hand and A. solani and F. fulva on the other hand and also in terms of similarities of responses of closely related tomato varieties to fertilizers.Keywords: Calcium, fungal diseases, green-life, magnesium, shelf-life, Solanum lycopersicu

Uncovering tomato quantitative trait loci and candidate genes for fruit cuticular lipid composition using the Solanum pennellii introgression line population

[EN] The cuticle is a specialized cell wall layer that covers the outermost surface of the epidermal cells and has important implications for fruit permeability and pathogen susceptibility. In order to decipher the genetic control of tomato fruit cuticle composition, an introgression line (IL) population derived from a biparental cross between Solanum pennellii (LA0716) and the Solanum lycopersicum cultivar M82 was used to build a first map of associated quantitative trait loci (QTLs). A total of 24 cuticular waxes and 26 cutin monomers were determined. They showed changes associated with 18 genomic regions distributed in nine chromosomes affecting 19 ILs. Out of the five main fruit cuticular components described for the wild species S. pennellii, three of them were associated with IL3.4, IL12.1, and IL7.4.1, causing an increase in n-alkanes (>= C-30), a decrease in amyrin content, and a decrease in cuticle thickness of similar to 50%, respectively. Moreover, we also found a QTL associated with increased levels of amyrins in IL3.4. In addition, we propose some candidate genes on the basis of their differential gene expression and single nucleotide polymorphism variability between the introgressed and the recurrent alleles, which will be the subjects of further investigation.Research at the IBMCP was supported by the Spanish Ministry of Education and Culture (BIO2013-42193-R) and H2020 TRADITOM (634561). AA, AG, and J-PF-M thank COST FA1106 Quality Fruit for STSM and networking activities. This work was supported by the Israel Science Foundation (ISF) personal grant to AA (grant no. 646/11). We would like to thank the Adelis Foundation, the Leona M. and Harry B. Helmsley Charitable Trust, the Jeanne and Joseph Nissim Foundation for Life Sciences, Tom and Sondra Rykoff Family Foundation Research, and the Raymond Burton Plant Genome Research Fund for supporting AA's laboratory activity. AA is the incumbent of the Peter J. Cohn Professorial Chair. We are very grateful to Prof. Dani Zamir for providing us the S. pennellii IL collection and to Prof. Antonio Heredia for his valuable advice in preparing the manuscript for publication. We would like to acknowledge the help offered by the Electron Microscopy Unit at the WIS (Israel) for the TEM sample preparation and imaging, especially Elena Kartvelishvily, Eugenia Klein, and Eyal Shimoni. Finally, we would also like to thank Calanit Raanan and Tamara Berkutzki (Department of Veterinary Resources, WIS) for their help in tissue fixation and embedding, as well as Hanna Levanony (Department of Plant Sciences, WIS) for her help in tissue staining for the light microscopy studies.Fernández Moreno, JP.; Levy-Samoha, D.; Malitsky, S.; Monforte Gilabert, AJ.; Orzáez Calatayud, DV.; Aharoni, A.; Granell Richart, A. (2017). Uncovering tomato quantitative trait loci and candidate genes for fruit cuticular lipid composition using the Solanum pennellii introgression line population. Journal of Experimental Botany. 68(11):2703-2716. https://doi.org/10.1093/jxb/erx134S27032716681

Effects of coconut oil and palm kernel oil treatments on ripening process in banana fruits

No Abstract.Cameroon Journal of Experimental Biology Vol.2(1) 2006: pp. 16-2