Variation for Composition and Quality in a Collection of the Resilient Mediterranean 'de penjar' Long Shelf-Life Tomato Under High and Low N Fertilization Levels.

The 'de penjar' tomato (Solanum lycopersicum L.) is a group of local varieties from the Spanish Mediterranean region carrying the alc mutation, which provides long shelf-life. Their evolution under low-input management practices has led to the selection of resilient genotypes to adverse conditions. Here we present the first evaluation on nutritional fruit composition of a collection of 44 varieties of 'de penjar' tomato under two N fertilization levels, provided by doses of manure equivalent to 162 kg N ha-1 in the high N treatment and 49 kg N ha-1 in the low N treatment. Twenty-seven fruit composition and quality traits, as well as plant yield and SPAD value, were evaluated. A large variation was observed, with lycopene being the composition trait with the highest relative range of variation (over 4-fold) under both N treatments, and significant differences among varieties were detected for all traits. While yield and most quality traits were not affected by the reduction in N fertilization, fruits from the low N treatment had, on average, higher values for hue (5.9%) and lower for fructose (-11.5%), glucose (-15.8%), and total sweetness index (-12.9%). In addition, lycopene and ß-carotene presented a strongly significant genotype × N input interaction. Local varieties had higher values than commercial varieties for traits related to the ratio of sweetness to acidity and for vitamin C, which reinforces the appreciation for their organoleptic and nutritional quality. Highest-yielding varieties under both conditions displayed wide variation in the composition and quality profiles, which may allow the selection of specific ideotypes with high quality under low N conditions. These results revealed the potential of 'de penjar' varieties as a genetic resource in breeding for low N inputs and improving the organoleptic and nutritional tomato fruit quality.

Nutritional Characterization of a Traditional Cultivar of Tomato Grown Under Organic Conditions-cv. "Malacara".

The loss of genetic diversity due to the replacement of local tomato (Solanum lycopersicum L.) varieties by improved cultivars has been mitigated in many cases by the good work of organic farmers in maintaining local agricultural biodiversity. In parallel to these initiatives, in recent years, consumers have developed an increasing awareness of both food-related health, environmental issues, and food demand to recover the flavors of the past. In the case of tomatoes, these attributes (nutritional, organoleptic, social, and environmental) are closely related to organic production using local varieties. "Malacara" tomato is an example of a local variety. Coming from Sierra de Cádiz, it is a varietal type called "Cuelga" ("for hanging," because the tomato trusses are hung from beams in the farmhouses). Cultivated and harvested in the open air during the summer months, these tomatoes are commercialized and consumed in the winter. Historically, this variety has enabled the fresh consumption of tomatoes during the winter, without the need to force cultivation. It is highly appreciated in the local cuisine and is the basis for sauces figuring in typical dishes. Its characteristic traits are small, pallid fruits, and long shelf life. The main objective of this work has been to typify two Malacara tomato cultivars (red and yellow color) grown under organic farming conditions, through the characterization of morphological, nutritional, and volatile parameters. The main differences are due to morphological parameters (fruit weight and color of the exocarp and endocarp). Other characteristics such as the content of ash, fiber, moisture, the concentration of iron, magnesium, and calcium, and content of lycopene are different between both cultivars. This study provides information on the nutritional and aromatic composition of two Malacara tomato cultivars, differentiated by their color and grown under organic farming conditions. The results add value to the native horticultural heritage and can aid in the selection of tomato varieties suitable for a sustainable production system and to produce tomatoes with high nutritional value and rich in aroma.

Insights Into the Adaptation to Greenhouse Cultivation of the Traditional Mediterranean Long Shelf-Life Tomato Carrying the alc Mutation: A Multi-Trait Comparison of Landraces, Selections, and Hybrids in Open Field and Greenhouse.

Long shelf-life tomato (Solanum lycopersicum) landraces, characterized by carrying the alc allele in the NOR.NAC locus, have been traditionally cultivated in the Mediterranean region. These materials are adapted to open field conditions under low input conditions. However, cultivation under greenhouse is expanding fueled by increasing demand of these traditional tomatoes. We hypothesize that the large diversity in the long shelf-life landraces and derived materials can be exploited for adaptation to these new cultivation conditions. We have evaluated 12 varieties (seven landraces, three selections and two hybrids) carrying the alc mutation under open field (OF) and greenhouse (GH) cultivation, and evaluated them for 52 morphological, agronomic, chemical properties, and chemical composition descriptors. All descriptors, except six morphological ones, were variable. The variety effect was the greatest contributor to variation for most morphological traits, as well as for fruit weight, fruit shape, dry matter, and soluble solids content. However, significant environmental and genotype × environment interaction were found for 36 and 42 descriptors, respectively. Fruits from GH plants had lower weight and firmness and were less red than those from OF. On average, in GH yield was 35% lower and daily fruit weight loss in post-harvest 41% higher than in OF. However, fruits from GH had on average higher dry matter and soluble solids contents, antioxidant activity, glucose, fructose, and ascorbic acid concentrations, but lower contents in lycopene and ß-carotene than those from OF. A principal components analysis clearly separated varieties according to the cultivation environment. However, the distribution pattern of varieties within each of the two clusters (GH and OF) was similar, despite the strong G × E interaction for many descriptors. Landraces from the same origin plotted in the same area of each cluster, and selections and hybrids plotted together with the landraces. The results reveal a high impact of the cultivation environment on morphological, agronomic, chemical properties, and chemical composition of Mediterranean long shelf-life traditional tomato varieties. This suggests that breeding programs specifically focused to adaptation to greenhouse conditions should be developed.

Fruit composition diversity in land races and modern pepino (Solanum muricatum) varieties and wild related species.

Pepino (Solanum muricatum) fruits from 15 accessions of cultivated pepino as well as six accessions from wild relatives were evaluated for contents in dry matter, protein, ß-carotene, chlorophylls and seven minerals. Several-fold differences among accessions were found for most traits. Average values obtained were similar to those of melon and cucumber, but the phenolic contents were much higher. Wild species had significantly higher average contents for all traits vs. the cultivated pepino accessions. And, the comparisons among the cultivated pepino varieties showed that the modern varieties were more uniform in composition, and they possessed significantly lower concentrations of protein, P, K, and Zn than local land races. Most of the significant correlations among composition traits were positive. Our studies show that regular consumption of pepino fruits could make a significant contribution to the recommended daily intake of P, K, Fe and Cu as well as to the average daily intake of phenolics. Furthermore, the higher values for most nutrients measured in the wild species and in the local land races indicate that new pepino varieties with improved fruit contents in nutrient and bioactive compounds can be developed.

Characterization of composition traits related to organoleptic and functional quality for the differentiation, selection and enhancement of local varieties of tomato from different cultivar groups.

Tomato (Solanum lycopersicum) local varieties are having an increasing demand. We characterized 69 local tomato accessions from eight cultivar groups for proximate composition traits, major sugars, acids and antioxidants. A large diversity was found, with differences among accessions of almost tenfold for lycopene. Significant differences were found among cultivar group means for most traits. The Cherry and Penjar groups generally presented higher dry matter, soluble solids content, titratable acidity, taste index, ß-carotene, ascorbic acid, total phenolics, and antioxidant activity that the other groups. Wide ranges of variation were found within each cultivar group. Positive correlations were found between proximate traits related to taste and antioxidants. The multivariate principal components analysis confirms the distinct profile of the Cherry and Penjar groups and the large variation within groups. The results will be useful for the differentiation, enhancement and selection of local tomato varieties with improved organoleptic properties and functional quality.

Diversity for chemical composition in a collection of different varietal types of tree tomato (Solanum betaceum Cav.), an Andean exotic fruit.

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