Sustainable cultivation of melon landraces: Effects of grafting on the accumulation of flavor-related compounds.

Melon landraces are highly appreciated by consumers who pay price premiums to compensate for lower yields, enabling on-farm conservation. However, they are highly susceptible to soilborne diseases. This study analyses the impact of Cucurbita and Cucumis rootstocks on the accumulation of flavor-related metabolites in Spanish landraces of the Ibericus melon group, as a strategy to promote their sustainable cultivation. Scion genotype was the main factor conditioning the accumulation of sugars and acids both under standard and saline organic farming conditions. The effects of grafting on organic acid accumulation were negligible, while the effects on sugar content were significant. The latter effects were dependent on specific scion-rootstock combinations, though wild Cucumis (e.g. Fian) rootstocks represent an alternative that should be further studied. The effect on the accumulation of volatiles was limited, and again depended on specific scion-rootstock combinations. The rootstock effect even differed between populations of the same landrace.

The SNP g.1311T>C associated with the absence of ß-casein in goat milk influences CSN2 promoter activity.

Quantitative individual differences in the amount of ß-casein in goat milk are determined by at least nine alleles. In particular, two alleles (CSN2(0) and CSN2(01) ) are associated with an undetectable amount of this protein in milk. The CSN2(01) allele is characterized by a single nucleotide substitution at position 373 of the seventh exon (AJ011018:g.8915C>T), responsible for the formation of a premature stop codon at the 182 position. Herein, we report the contribution of the SNP g.1311T>C, which demonstrates a linkage with the SNP AJ011018:g.8915C>T, to the promoter transcriptional activity. Particularly, we indicate that the nucleotide C at position 1311 negatively affects the promoter activity of the CSN2 gene.

Application of genomic tools in plant breeding.

Plant breeding has been very successful in developing improved varieties using conventional tools and methodologies. Nowadays, the availability of genomic tools and resources is leading to a new revolution of plant breeding, as they facilitate the study of the genotype and its relationship with the phenotype, in particular for complex traits. Next Generation Sequencing (NGS) technologies are allowing the mass sequencing of genomes and transcriptomes, which is producing a vast array of genomic information. The analysis of NGS data by means of bioinformatics developments allows discovering new genes and regulatory sequences and their positions, and makes available large collections of molecular markers. Genome-wide expression studies provide breeders with an understanding of the molecular basis of complex traits. Genomic approaches include TILLING and EcoTILLING, which make possible to screen mutant and germplasm collections for allelic variants in target genes. Re-sequencing of genomes is very useful for the genome-wide discovery of markers amenable for high-throughput genotyping platforms, like SSRs and SNPs, or the construction of high density genetic maps. All these tools and resources facilitate studying the genetic diversity, which is important for germplasm management, enhancement and use. Also, they allow the identification of markers linked to genes and QTLs, using a diversity of techniques like bulked segregant analysis (BSA), fine genetic mapping, or association mapping. These new markers are used for marker assisted selection, including marker assisted backcross selection, 'breeding by design', or new strategies, like genomic selection. In conclusion, advances in genomics are providing breeders with new tools and methodologies that allow a great leap forward in plant breeding, including the 'superdomestication' of crops and the genetic dissection and breeding for complex traits.

Utilización de gráficos de crecimiento infantil / Children growth charts utilization

Impresiona un abandono casi total del uso de gráficos de crecimiento en la evaluación nutricional del niño. La introducción de los Cuadernos de Chile Crece Contigo no ha conseguido revertir esta situación. Su distribución está limitada a las maternidades públicas, los gráficos presentan dificultades por su exiguo tamaño y la supervisión es nula. Se decidió cuantificar la utilización de gráficos y evaluar la percepción nutricional de las madres. Se realizaron entrevistas a madres de niños(as) de 12-59 meses, en Consultorios de Lo Espejo, área sur de Santiago, que portaran un carnet de control. Se registraron los datos del paciente, edad y nivel educacional de la madre. Se consultó a la madre sobre el estado nutricional del niño. Luego se le mostraron datos de una niña en 4 formatos diferentes: valores numéricos, desviación estándar, gráfico y porcentaje de la mediana, solicitando definir el estado nutricional del caso e indicar las preferencias sobre las formas de presentación. Se analizaron 109 carnets, 10 de Chile Crece Contigo; de los cuales, uno tenía el gráfico con curva dibujada; de los otros 99, de diseño antiguo, sólo 11 tenían un gráfico impreso y ninguno tenía la curva de crecimiento del niño dibujada. De las madres entrevistadas, 2 eran menores de 20 años y el 65 por ciento completó la enseñanza media. El 83 por ciento definió satisfactoriamente el estado nutricional del hijo(a) y el 60 por ciento lo hizo en relación al caso mostrado, siendo esto último relacionado significativamente con el nivel escolar materno. La forma de presentación de datos preferido fue el de valores absolutos (41 por ciento), seguido del gráfico con un 28 por ciento. Este estudio demuestra el abandono de los gráficos como forma de visualización del crecimiento infantil, herramienta básica tanto para madres como para profesionales y alerta sobre las consecuencias de esta situación en la detección precoz de desvíos nutricionales y el retraso en las medidas correctivas...

Growth charts are barely used in most of public clinics. In many cases have been replaced by booklets without a growth chart. The new “Chile Crece Contigo” booklet has not solved this pitfall. Its distribution is limited to public maternities, and the charts are tiny making difficult its proper use. In this operational study, was intended to quantify the use of growth charts and to assess mother’s perception of children nutritional status. Mothers of children aged 12-59 months were interviewed in Municipal Outpatient Clinics in Lo Espejo, Santiago. After collecting basic child data, mother’s age and educational level, the growth chart was evaluated. Mothers were requested to diagnose their child’s nutritional status. Then, they were presented with a specially prepared set of nutritional data of an imaginary child in four different formats: numeral values, standard deviations, growth chart and percentage of median weight for age, asking them again for their nutritional diagnose and format preferences. Of 109 booklets observed, 10 were “Chile Crece Contigo” format and only one these has a chart completely plotted. Of the other 99 old booklets, only 11had a printed chart on it and not a single one has data plotted. An 83 percent made a correct nutritional assessment of her child and 60 percent in relation with the case exhibited; in this second case it was a significant correlation with educational level. The preferred format was plain numbers with growth charts as second preference. This study confirms the surprising reduction in the use of growth charts, a very valuable aid in monitoring child growth both for mothers and health workers, and should represent a warning for its consequence in early detection of nutritional deviations. Through this study we also intent to promote more investigation on the issue and the design of public policies to extend and improve the use of growth charts in the area and in the country.

Bin mapping of genomic and EST-derived SSRs in melon (Cucumis melo L.).

We report the development of 158 primer pairs flanking SSR motifs in genomic (gSSR) and EST (EST-SSR) melon sequences, all yielding polymorphic bands in melon germplasm, except one that was polymorphic only in Cucurbita species. A similar polymorphism level was found among EST-SSRs and gSSRs, between dimeric and trimeric EST-SSRs, and between EST-SSRs placed in the open reading frame or any of the 5'- or 3'-untranslated regions. Correlation between SSR length and polymorphism was only found for dinucleotide EST-SSRs located within the untranslated regions, but not for trinucleotide EST-SSRs. Transferability of EST-SSRs to Cucurbita species was assayed and 12.7% of the primer pairs amplified at least in one species, although only 5.4% were polymorphic. A set of 14 double haploid lines from the cross between the cultivar "Piel de Sapo" and the accession PI161375 were selected for the bin mapping approach in melon. One hundred and twenty-one SSR markers were newly mapped. The position of 46 SSR loci was also verified by genotyping the complete population. A final bin-map was constructed including 80 RFLPs, 212 SSRs, 3 SNPs and the Nsv locus, distributed in 122 bins with an average bin length of 10.2 cM and a maximum bin length of 33 cM. Map density was 4.2 cM/marker or 5.9 cM/SSR.

Genetic diversity of a germplasm collection of Cucurbita pepo using SRAP and AFLP markers.

Cucurbita pepo is a highly polymorphic species. The cultivars can be grouped into eight morphotypes in two subspecies, ssp. pepo and ssp. ovifera. A collection of 69 accessions representative of the morphotypes and some unclassified types was used for analysing the morphological and molecular diversity of this species. This collection includes commercial cultivars and Spanish landraces, which represent the great diversification of types that have arisen in Europe after this species arrived from America. For the molecular variability studies, two PCR-based systems were employed, AFLP and SRAP, which preferentially amplify ORFs. Principal coordinates analysis and cluster analysis using the UPGMA method clearly separate the accessions into the two subspecies through the use of both markers. However, the gene diversity and the genetic identity values among morphotypes and subspecies varied between the two marker systems. The information given by SRAP markers was more concordant to the morphological variability and to the evolutionary history of the morphotypes than that of AFLP markers. In ssp. ovifera, the accessions of the different morphotypes were basically grouped according to the fruit colour. This may indicate different times of development and also the extent of breeding in the accessions used. This study has allowed identification of new types that can be employed for the development of new cultivars. The landraces of the spp. ovifera, used as ornamental in Europe, have proved to be of great interest for preserving the diversity of C. pepo.