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Se ilustra el procedimiento para encontrar un modelo que sea útil para obtener pronósticos mensuales de un productos de limpieza en el mercado colombiano. Se hace explícita la metodología de Box y Jenkins para obtener el modelo final con un ejemplo del proceso completo de modelaje. Además, se presenta una comparación entre los niveles pronosticados y realizados extendiendo la utilización de distintos modelos para los diferents productos. [ABSTRACT FROM AUTHOR]

This paper presents the common elements of the multivariate multiple regression, multivariate analysis of variance (manova), canonical correlation analysis and discriminant analysis of canonical variates focusing on the statistical tests and, in some extent, on the mathematics behind the techniques [ABSTRACT FROM AUTHOR]

The main purpose of this paper is developing and applying a methodology based on multivariate statistical procedures to endorse a classification of certain rural regions in Colombia. In order to achieve the aims, cluster analyses were the basic procedures made. The techniques of principal components, canonical variates, discriminant analysis and Andrews' plots were used to validate the cluster analyses results. [ABSTRACT FROM AUTHOR]

One of the major production limiting diseases in coffee is the orange leaf rust caused by the fungus Hemileia vastatrix (Berkeley and Broome). Little is known about the inheritance and genetic determinism of partial resistance in coffee ( C. arabica L.) to H. vastatrix. This information would be useful to breed durable resistant cultivars efficiently. In this report, a genetic analysis of partial resistance to leaf rust in Coffea arabica was performed using nine segregating progenies from a cross between the susceptible variety Caturra and the resistant introgressed line DI200. Evolution of partial resistance was evaluated under field conditions by measuring rust incidence (RI) and defoliation (DEF) in two separate regions of productive branches per tree and during four successive years (2003–2006). Genetic components of rust resistance were estimated using the Means and Variance Generation Method, under an additive-dominant model. The most important genetic effect was the additive one, while resistance heritability estimates ranged from 73 to 53% for broad and narrow sense heritabilities, respectively. Genetic estimates for the number of segregating genes showed that at least five independent genes or genetic regions are implicated in the partial resistance to rust. We further analyzed the presence of resistance (RGC) and defense (DGC) gene candidates in the resistant and susceptible parents by using a degenerated-primer PCR approach. A total of 40 different genomic coffee sequences were isolated exhibiting strong similarity to known RGC or DGC homologous. Phylogenetic analysis clustered these sequences into nine families. One family exhibited the TIR protein element, representing the first TIR class proteins identified in coffee. While genetic analysis suggest a predictable success in the processes to improve the selection of resistant lines for future varieties with durable resistance, the molecular characterization of candidate genes represent a primary approach towards the identification of mechanisms involved in partial resistance to coffee leaf rust. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify polymorphic molecular markers associated with partial resistance to coffee leaf rust, Hemileia vastarix. A segregating F2 population derived from a cross between the susceptible Coffea arabica cv. Caturra and a C. canephora-introgressed Arabica line exhibiting high partial resistance was analyzed. Rust resistance measured as rust incidence (RI) and defoliation (DEF) was evaluated in field conditions in three consecutive years (2003–2005). During the 2003 season, which was characterized by favorable conditions for a rust epidemic, the F2 plants exhibited different levels of resistance ranging from very susceptible (50.1% for DEF and 49.5% for RI) to highly partial resistance (9.1% for DEF and 3.7% for RI). Molecular analysis enabled identification of seven polymorphic markers (5 AFLP and 2 SSR) exhibiting significant association with partial resistance. Coexistence of resistance homozygous alleles (RR) at codominant SSR loci was correlated with high resistance. This study is the first attempt to develop PCR-based sequence specific markers linked to partial rust resistance in coffee. [ABSTRACT FROM AUTHOR]