SECTION B: LIFE SCIENCES
The capulí tree (Prunus serotina subsp. capuli) belongs to the Rosaceae family and is native to North America, although it is widely distributed in cold and temperate areas of South America, especially in Ecuador. Its fruit is a small berry of high commercial interest due to the therapeutic substances it contains, such as antioxidants, associated with the treatment of cardiovascular and inflammatory diseases. Both national producers and ancestral communities use it for the production of jams and fermented beverages and/or spirits. However, there are no agricultural crops established as such in Ecuador, so it is interesting to study their reproduction mechanisms in order to apply them in agricultural and reforestation programs. In species such as P. serotina, it is important to understand the GSI (gametophytic self-incompatibility) mechanism that has evolved in hermaphrodite flowers to avoid inbreeding and that implies a limitation for fruit production. GSI is controlled by the S Locus, consisting of the S-RNase gene (expressed in the pistil) and the SFB gene (expressed in the pollen). The dynamic between the two genes activates or deactivates certain proteins that influence the compatibility or incompatibility of a specific cross, functioning as a molecular complex like a lock and a key. This system prevents crosses between genetically related individuals from generating fruits, since it truncates the growth of pollen tubes, preventing them from reaching the ovary for fertilization. The objective of this research was to study the expression of the S-RNase gene in compatible and incompatible crosses of capuli. For this purpose, controlled pollinations were carried out, RNA was extracted and RT-qPCR was performed. With the Ct values obtained from the qPCRs, statistical analyses were performed to determine the significance of gene expression between compatible and incompatible crosses. The study was complemented with an analysis of pollen tube development in different crosses to understand the relationship with S-RNase gene expression. The results suggest that, in the case of capuli, a suppression of the GSI system may occur, causing crosses considered incompatible to act as compatible.
viewed = 388 times