We evaluated 23 tree tomato (Solanum betaceum) accessions from five cultivar groups 24 and one wild relative (S. cajanumense) for 26 composition traits. For all traits we found 25 highly significant differences (P<0.001) among the materials studied. The high diversity 26 found within S. betaceum for composition traits was matched by a high diversity within 27 each of the cultivar groups. We found that sucrose and citric acid were the most 28 important soluble sugar and organic acid, respectively, in tree tomato. Fruit in the 29 anthocyanin pigmented (purple) group had a carotenoid content similar to that in the 30 yellow-orange cultivar groups. Total phenolic content was significantly correlated 31 (r=0.8607) with antioxidant activity. Analyses of mineral content showed that tree 32 tomato is a good source of K, Mg, and Cu. Multivariate principal components analysis 33 (PCA) confirmed that an important diversity exists within each cultivar group. The 34 results we have obtained indicate that the high diversity found within the tree tomato 35 could be exploited for selection and breeding for developing the tree tomato as a 36 commercial crop. 37 38

Acosta-Quezada, P.; Martinez-Laborde, J.; Prohens Tomás, J. (2011). Variation among tree tomato (Solanum betaceum Cav.) accessions from different cultivar groups: implications for conservation of genetic resources and breeding. Genetic Resources and Crop Evolution. 58 (6)

Elsevier Acosta-Quezada, P.; Riofrío-Cuenca, T.; Rojas, J.; Vilanova Navarro, S.; Plazas Ávila, MDLO.; Prohens Tomás, J. (2016). Phenological growth stages of tree tomato (Solanum betaceum Cav.), an emerging fruit crop, according to the basic and extended BBCH scale. Scientia Horticulturae. 199:216-223. doi:10.1016Horticulturae. 199:216-223. doi:10. /j.scienta.2015 The tree tomato (Solanum betaceum Cav.) is a small tree native to the Andean region cultivated for 18 its juicy fruits, which are having an increasing demand. Tree tomato is morphologically and 19 phenologically different from other Solanum crops and tools for the phenological description of the 20 developmental stages are needed for the enhancement of this emerging crop. We developed a basic 21 and an extended numerical BBCH (Biologische Bundesanstalt, Bundessortenamnt, Chemische 22 Industrie) scales which allow the precise identification of the phenological stages of tree tomato. 23 Eight principal stages are described for germination, leaf development, formation of side shoots, 24 stem elongation, inflorescence emergence, flowering, development of fruit, and ripening of fruit and 25 seed. The basic (two-digit) scale is sufficiently precise for germination, stem elongation, and 26 ripening of fruit and seed. However, for leaf development, formation of side shoots, inflorescence 27 emergence, flowering, and development of fruit the extended (three-digit) scale is considered 28 necessary for an adequate description. The description of the phenological stages is combined with 29 illustrations for clarification. The tree tomato BBCH scale has been validated by characterizing 24 30 accessions of different varietal groups for traits of agronomic interest and evaluating the differences 31 observed among accessions at specific BBCH developmental stages. The basic and extended BBCH 32 scales represent a useful tool for the description and identification of phenological scales of tree 33 tomato. These scales will be useful for the enhancement of this emerging fruit crop. 34 35

No abstract

Changing climatic conditions impose a challenge both to biodiversity and food security. The effects of climate change affect different aspects of the plant or crop, such as morphological and phenological aspects, as well as yield. The effects of greenhouse conditions might be comparable in some cases to a permanent extreme disturbance in climate and weather, thus, contributing to our knowledge on climate change impacts on plant species. We have investigated the differences for 23 traits in two cultivar groups of an Andean traditional crop, Solanum betaceum, under two different environmental conditions that correspond to the traditional practices in the open field and three cultural managements under greenhouse conditions (no fertilization or control, organic, and mineral). We found that traditional practices in the open field are the less productive. Moreover, in warmer and drier conditions the treatment with organic fertilization was the most productive. Greenhouse conditions, however, delay production. We further identified traits that differentiate both cultivar groups and traits that are linked to either the new climate conditions or the fertilization treatments. Fruit characteristics were quite homogeneous between the two cultivar groups. Overall, our results provide insight on the consequences that climate change effects might exert on crops such as tree tomato, reveal that greenhouses can be a robust alternative for tree tomato production, and highlight the need to understand how different managements are linked to different solutions to fulfil the farmers’ demands.