Search

[EN] BACKGROUND: The grafting of watermelons (Citrullus lanatus) is a common technique that increases yield under stressful soil conditions. Themost common rootstocks for watermelons are Cucurbita hybrids. However, they often have a negative impact on fruit quality. Exploiting novel Citrullus germplasm such as citronmelon (Citrullus lanatus var. citroides) is an alternative to avoid these quality problems. RESULTS: Citron melon has been validated as watermelon rootstock, comparing its effects on watermelon quality to those of Cucurbita hybrids. Larger fruits with thicker rinds were observed in fruits from plants grafted onto both citron and Cucurbita rootstocks. The citron melon had no significant effect on flesh sugars or acid profiles compared to non-grafted watermelons, except for an increase in glucose and malic acid content, which also occurred in the Cucurbita rootstocks. The aroma profile of fruits produced on citron melon was similar to that of the non-grafted and self-grafted controls. The citron rootstock did not display the increased levels of (Z)-6-nonen-1-ol (a compound associated with pumpkin-like odors) found in fruits produced with Cucurbita hybrids. CONCLUSION: The low impact of citron melon rootstock on fruit quality, along with the enhanced resistance against nematodes, make the citron a promising alternative to Cucurbita rootstocks. (C) 2016 Society of Chemical Industry, This study was partially supported by the project funded by the Ministerio de Economía y Competitividad AGL2014-53398-C2-2-R (jointly funded by FEDER).

[EN] BACKGROUND: Tomatoes are an important source of antioxidants (carotenoids, vitamin C, etc.) owing to their high level of consumption. There is great interest in developing cultivars with increased levels of lycopene, beta-carotene or L-ascorbic acid. There is necessary to survey new sources of variation. In this study, the potential of improvement for each character in tomato breeding programmes, in a single or joint approach, and the nature of genotype (G), environment (E) and G x E interaction effects in the expression of these characters were investigated. RESULTS: The content of lycopene, beta-carotene and ascorbic acid determined was very high in some phenotypes (up to 281, 35 and 346 mg kg(-1) respectively). The important differences in the three environments studied (with some stressing conditions in several situations) had a remarkable influence in the phenotypic expression of the functional characters evaluated. Nevertheless, the major contribution came from the genotypic effect along with a considerable G x E interaction. CONCLUSION: The joint accumulation of lycopene and beta-carotene has a high genetic component. It is possible to select elite genotypes with high content of both carotenoids in tomato breeding programmes but multi-environment trials are recommended. The improvement of ascorbic acid content is more difficult because the interference of uncontrolled factors mask the real genetic potential. Among the accessions evaluated, there are four accessions with an amazing genetic potential for functional properties that can be used as donor parents in tomato breeding programmes or for direct consumption in quality markets. (C) 2011 Society of Chemical Industry, This research was financed by the Spanish Ministry of Science and Innovation (MICINN) (project AGL2005-08083-C03-01). The authors thank Professor Jun Zhu, director of the Bioinformatics Institute, Zhejiang University, China, for his comments and for the software used in the data analyses.