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Abstract Background Opportunity and challenges of the agriculture scenario of the next decades will face increasing demand for secure food through approaches able to minimize the input to cultivations. Large panels of tomato varieties represent a valuable resource of traits of interest under sustainable cultivation systems and for genome-wide association studies (GWAS). For mapping loci controlling the variation of agronomic, fruit quality, and root architecture traits, we used a heterogeneous set of 244 traditional and improved tomato accessions grown under organic field trials. Here we report comprehensive phenotyping and GWAS using over 37,300 SNPs obtained through double digest restriction-site associated DNA (dd-RADseq). Results A wide range of phenotypic diversity was observed in the studied collection, with highly significant differences encountered for most traits. A variable level of heritability was observed with values up to 69% for morphological traits while, among agronomic ones, fruit weight showed values above 80%. Genotype by environment analysis highlighted the strongest genotypic effect for aboveground traits compared to root architecture, suggesting that the hypogeal part of tomato plants has been a minor objective for breeding activities. GWAS was performed by a compressed mixed linear model leading to 59 significantly associated loci, allowing the identification of novel genes related to flower and fruit characteristics. Most genomic associations fell into the region surrounding SUN, OVATE, and MYB gene families. Six flower and fruit traits were associated with a single member of the SUN family (SLSUN31) on chromosome 11, in a region involved in the increase of fruit weight, locules number, and fruit fasciation. Furthermore, additional candidate genes for soluble solids content, fruit colour and shape were found near previously reported chromosomal regions, indicating the presence of synergic and multiple linked genes underlying the variation of these traits. Conclusions Results of this study give new hints on the genetic basis of traits in underexplored germplasm grown under organic conditions, providing a framework for the development of markers linked to candidate genes of interest to be used in genomics-assisted breeding in tomato, in particular under low-input and organic cultivation conditions.

En esta investigación partimos de la premisa que desde la Antigüedad grecorromana hasta el siglo XIX, que es cuando aparecen los primeros descubrimientos en el campo de la biogenética, uno de los modelos de procreación que encontramos en el sur de Europa es intra-extrauterino. Un modelo que incluye cuatro etapas: concepción, embarazo, parto y lactancia. La leche humana es percibida como sangre menstrual que desaparece durante nueve meses para alimentar al embrión en el útero, ser desviada y purificada al transformarse en leche. En el imaginario colectivo, la frontera de los fluidos (sangre-leche), por su carácter de mutación, no está muy definida, siendo la sangre, en su sentido más amplio, el principio rector. Por eso se entiende que dos personas, hasta el momento no emparentadas biológicamente, al lactar de la misma mujer-nodriza, se puedan llegar a reconocer como hermanos-as de leche y, a la mujer lactante, madre de leche. A partir de esta premisa, el objetivo de esta investigación es hacer una propuesta teórica a la antropología del parentesco, al incorporar la leche humana en su doble dimensión simbólica: como alimento, por nuestra condición de mamíferos, y símbolo de la reproducción y, por tanto, del parentesco en el caso de circular y ser compartida. Para amparar esta propuesta se procederá al análisis de fuentes históricas, la etnología comparada, y al resultado de un estudio etnohistórico centrado en el papel que tuvieron las nodrizas domésticas en la construcción del parentesco de leche en España.

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 β-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.

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 β-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.

Este trabajo pretende introducir a los niños de cinco años en el método científico como proceso que favorece la adquisición y desarrollo de capacidades, habilidades y competencias en los alumnos, estimulando un desarrollo integral de la persona a nivel físico, cognitivo, emocional y social. Para ello, el diseño de la propuesta de trabajo ha abarcado desde una fundamentación teórica hasta la puesta en práctica de la misma. Este diseño, realizado a través de las fases del método aplicadas al estudio del caracol serrano, persigue desarrollar en los alumnos aspectos que contribuyan a su alfabetización científica y desarrollo integral, además de trabajar de manera transversal contenidos pertenecientes al currículo de Educación Infantil. Su puesta en práctica ha estado caracterizada por una metodología global y constructivista, teniendo como resultado aportaciones positivas en cuanto al rendimiento y desarrollo personal del alumno.

The European approach to rural development policies is gradually shifting to spatial differentiation, blending the territorial dimension. A differentiation of the rural character based on specific attributes of the territory is required, including lifestyles, supply of services and amenities and competition in soil use. We present a classification of the municipalities in Lombardy (Italy) aimed at providing recommendations for the development of regional policies. Grounding on four different and independently developed thematic classification relating to the heterogeneity in urban-rural linkages, the social morphology, the economic geography and the geographical morphology we construct a unified classification of municipalities that considers the multidimensionality of the rural attribute.