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Bouteloua curtipendula Michx. Torr. (sideoatsgrana) is a native grass in Mexico, but a structured use of its genetic diversity is missing. Amplified fragments length polymorphism (AFLP) analysis was conducted to define genetic relationships among 90 sideoatsgrama populations. Five AFLP primer combinations of EcoRI and MseI produced 281 bands, 36.6% of which were polymorphic, and the 104 most consistent of these were used for analysis. Genetic similarities were based on the Jaccard coefficient. Functional groups were established through principal component analysis (PCA) and cluster analysis (CA). Jaccard's coefficients varied from 0.0 to 0.82. Polymorphic bands ranged from 11 for EcoRI-AGG+MseI-CTA, to 29 for EcoRI-ACA+MseI-CAC. PCA established two groups based on genetic polymorphism that were consistent with the CA. The two first principal components explained 21.8% of the total variation. The PCA provided evidence to integrate germplasm of populations from Mexico's semi-arid areas. The dendogram resulting from unweighted pair group methods using arithmetic averages (UPGMA) divided the 90 populations in two groups. Genetic variability in these populations was directly related to the geographic origin of the germplasm, as well as to seed movement due to different factors. Native sideoatsgrama populations, in Mexico, maintain high levels of genetic variation, and this study provides useful information for its efficient use and conservation.

Odor approximations of orange and melon flavors were performed using an array of quartz crystal microbalance (QCM) odor sensors coated with different materials, such as lipids and stationary phase materials of gas chromatography (GC). The steady state sensor responses to single flavor components were measured and the data were used to estimate the important odor components by means of a computational two-level quantization method. From these results, the experimental approximations using the steady state sensor responses and principal component analysis (PCA) were performed. In both cases, orange and melon flavors, it was possible to approximate the recipes with only three odor components. Moreover, the similarities between the approximated odors and the original ones were evaluated by a human sensory test. It was found that these similarities were high, especially in the case of orange flavor.