2014). Differential RNA-and protein-expression proles of cactus seeds capable of hydration memory . AbstractHydration memory is a phenomenon in which a seed can tolerate discontinuous hydration periods, displaying enhanced germination after one or multiple hydration -dehydration (HD) cycles; it was described physiologically in a few cactus species around 15 years ago. Although no additional work was done on this subject, it has great biotechnological potential since its analysis would permit predictions about whether a seed can withstand discontinuous hydration; in the long run, the knowledge about its regulation might lead to induction of this resistance, so we aimed to provide an initial approach to the molecular mechanisms that underlie hydration memory. This phenomenon was reproduced successfully in our lab with Ferocactus peninsulae seeds. Using two-dimensional (2D) electrophoresis, we compared expression patterns of proteins involved in seed maturation of seeds and seedlings subjected to an HD cycle treatment. We found differential expression of several proteins possibly involved in primary metabolism, ubiquitination pathway and reserve protein availability regulation in seeds and seedlings subjected to an HD cycle. We also found differential stability of total RNA. These results strongly suggest that the differential expression of proteins is at least partially related to the hydration memory process.

Br au l io e Dga r h e r r e r a-c a Br e r a 1, *, v ic tor m a n u e l sa l a Z a r-roJa s 1, 2 , a Dr i a na De lga Do -a lva r a Do 1 , Jorge c a m pos-con t r e r a s 2 , a nd J ua na ce rva n t e s-va rga s 1 1 colegio de postgraduados en ciencias agrícolas -campus puebla, programa de estrategias para el Desarrollo agrícola regional. km. 125.5 carr. Fed. méx.-pue. col. la libertad. puebla, pue, mexico. 2 universidad nacional autónoma de méxico -unidad de Biología, tecnología y prototipos (uBipro), Facultad de estudios superiores, iztacala. av. De los Barrios no. 1, los reyes iztacala, tlalnepantla edo. de méxico * corresponding author: braulio_edgar@hotmail.co.uk; behc@colpos.mx AbstrAct the use and conservation of Vanilla planifolia Jack. in Mexico requires comprehensive and detailed analysis of its genetic variation and of the issues that determine it. For this reason, we studied the variation in phytochemical contents that define vanilla aroma quality by HPlc (High Performance liquid chromatography) to identify genetic variation at the infraspecific level among 14 microsatellite loci and to study assessment criteria which determine the attitude of stakeholders regarding use and conservation of vanilla germplasm in the totonacapan region, Mexico. to this end we used the multi-attribute analysis method, aHP (analytic Hierarchy Process). the results showed the existence of six phytochemical groups (chemotypes) within V. planifolia germplasm, each with specific aromatic characteristics. the 14 loci analyzed were polymorphic for vanilla chemotypes with variable sizes, and genetic clustering of accessions coincided with phytochemical grouping (chemotypes). it was noted that the process of economic and cultural valuation of users has caused aromatic variation in vanilla germplasm, and this variation has been conserved at the regional level. thus, the data indicate that in the probable center of origin of vanilla there is genetic and phytochemical variation, knowledge of which is fundamental to the design of breeding programs to optimize the benefits of vanilla production for stakeholders and to contribute to the conservation of the primary gene pool of Vanilla planifolia.

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One of the threats in the diversity loss of the primary gene pool of Vanilla planifolia is the lack of information on existing level of polymorphism in cultivated germplasm, and the different expressions of this polymorphism. For this reason, it is proposed to study the chemical polymorphism of the four phytochemicals that define the vanilla aroma quality in fruits (vanillin, vanillic acid, p-hydroxybenzaldehyde, p-hydroxybenzoic acid) by HPLC analysis (High Performance Liquid Chromatography) of 25 collections of unknown genotype, grown in the region Totonacapan Puebla-Veracruz, Mexico. The results identified a selection process, domestication in fruit aroma of vanilla, during which increased the participation of vanillin and reduced the presence of three minor compounds (vanillic acid, p-hydroxybenzaldehyde and p-hydroxybenzoic acid) in the global aroma. We distinguished a total of six chemotypes of V. planifolia in the Totonacapan region, some chemotypes with wild aromatic characteristics (low participation of vanillin) related to the material less cultivated in the region and domesticated chemotypes with high participation of vanillin, for the most cultivated material. The results show that the diversification of the chemotypes of V. planifolia is not related to environmental variation. The data indicate that in the possible center of origin of vanilla, there is phytochemical polymorphism, which indirectly suggests the existence of genetic polymorphism, essential for the design of a breeding program for optimizing the use and conservation of diversity of the primary gene pool of Vanilla planifolia.