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Giving us permission to rethink educational practices requires us to problematize our daily lives in order to reach a listening to the different voices, to rescue the echoes, the noises and the mere opinions that allow us to transgress the established, which has become rigid and dogmatic. It is of vital importance to educate oneself and others in concrete practices of cooperative work that guarantee the presence of better individuals in terms of their human, personal and social relations, and that place at the center the learning to live together and prepare oneself for a richer collaboration in daily life. In order to propose a project of social change from educational practices, individual and collective initiatives that involve the economic, political, ideological and social aspects should be valued, promoting the full development of the multiple facets of the individual. Therefore, it is possible to consider cooperative education based on experiences of self-management pedagogy, where the main objective is the transformation of educational processes and integrated to the active participation of all interested. Self-management education involves students, teachers, families and the community ; Darnos permiso para repensar sobre las prácticas educativas, nos exige problematizar nuestra cotidianidad para poder alcanzar una escucha sobre las diferentes voces, rescatar los ecos, los ruidos y las meras opiniones que permita transgredir lo establecido, lo que se ha vuelto rígido y dogmático. Es de vital importancia educarse y educar en prácticas concretas del quehacer cooperativo que garanticen la presencia de mejores individuos en cuanto a sus relaciones humanas, personales y sociales que coloque en el centro el aprender a convivir y prepararse a una colaboración más rica para la vida cotidiana.Para proponer un proyecto de cambio social desde las prácticas educativas se debe valorar las iniciativas individuales y colectivas que involucre a lo económico, político, ideológico y social fomentando un pleno desarrollo de las múltiples facetas del individuo. Por lo tanto, se puede considerar la educación cooperativa sustentada en experiencias de pedagogía autogestionaria, donde su objetivo principal es la trasformación de los procesos educativos e integrados a la participación activa de todos/as los/as interesados/as. La pedagogía autogestionaria involucra a los estudiantes, profesores, familias y comunidad

5 Pags. The definitive version is available at: http://www.actahort.org/index.htm ; The importance of mango growing contrasts with the paucity of information on its reproductive biology. In this work, the reproductive biology of mango was studied in the subtropical conditions of the Southern Spanish Mediterranean coast, using the cultivars 'Osteen', 'Kensington', 'Kent' and 'Keitt'. In order to establish the appropriate developmental coordinates during the reproductive phase, phenology was studied from the start of the blooming season to fruit harvest. Also to detect the reasons behind the low fruit set in mango, pollen tube pathway and fertilization were analysed, using microscopy techniques. A good proportion of the flowers were male and dropped soon after anthesis. Pollen grains readily germinated, pollen tubes reached the base of the style within one day, penetrated the ovule through the nucellus and reached the embryo sac three days after pollination. Endosperm nuclei soon developed, but the embryo remained in a quiescent stage. A good proportion of the ovules degenerated at different stages of development. Temperature had an effect on pollen performance, and low temperatures hampered pollen germination. Finally, a compatibility assay was performed, showing no differences between self and cross pollen tube growth in the style. However a paternity analysis, with microsatellite markers, showed significant differences in outcrossing rate depending on the availability of pollinizer trees. ; V. Pérez thanks to Cabildo de La Palma-CSIC for a PhD grant. Support to this work was provided by the Spanish Ministry of Science and Innovation (MICINN)- European Regional Development Fund, European Union (AGL2010-15140 and AGL2012-40239 grants). ; Peer reviewed

Most flowering plants show porogamy in which the pollen tubes reach the egg apparatus through the micropyle. However, several species show chalazogamy, an unusual pollen tube growth, in which the pollen tubes reach the embryo sac through the chalaza. While ovary signals for pollen tube growth and guidance have been extensively studied in porogamous species, few studies have addressed the process in chalazogamous species such as mango (Mangifera indica L.), one of the five most important fruit crops worldwide in terms of production. In this study, we characterize pollen–pistil interaction in mango, paying special attention to three key players known to be involved in the directional pollen tube growth of porogamous species such as starch, arabinogalactan proteins (AGPs), and γ-aminobutyric acid (GABA). Starch grains were observed in the style and in the ponticulus at anthesis, but their number decreased 1 day after anthesis. AGPs, revealed by JIM8 and JIM13 antibodies, were homogenously observed in the style and ovary, but were more conspicuous in the nucellus around the egg apparatus. GABA, revealed by anti-GABA antibodies, was specifically observed in the transmitting tissue, including the ponticulus. Moreover, GABA was shown to stimulate in vitro mango pollen tube elongation. The results support the heterotrophic growth of mango pollen tubes in the style at the expense of starch, similarly to the observations in porogamous species. However, unlike porogamous species, the micropyle of mango does not show high levels of GABA and starch, although they were observed in the ponticulus and could play a role in supporting the unusual pollen tube growth in chalazogamous species. ; This research was supported by the Spanish 'Ministerio de Ciencia e Innovación' – European Regional Development Fund, European Union (PID2019-109566RB-I00, AGL2015-74071-JIN, and RYC-2017-21909) and Junta de Andalucia (Proyecto de Excelencia P18-RT-3272). Distribution of the JIM antibodies used in this work was supported in part by NSF grants DBI-C421683 and RCN009281. VP was supported by a Cabildo Insular de La Palma-CSIC contract. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). ; Peer reviewed

Self-incompatibility (SI) to self-compatibility (SC) transition is one of the most frequent and prevalent evolutionary shifts in flowering plants. Prunus L. (Rosaceae) is a genus of over 200 species most of which exhibit a Gametophytic SI system. Peach [Prunus persica (L.) Batsch; 2n = 16] is one of the few exceptions in the genus known to be a fully self-compatible species. However, the evolutionary process of the complete and irreversible loss of SI in peach is not well understood and, in order to fill that gap, in this study 24 peach accessions were analyzed. Pollen tube growth was controlled in self-pollinated flowers to verify their self-compatible phenotypes. The linkage disequilibrium association between alleles at the S-locus and linked markers at the end of the sixth linkage group was not significant (P > 0.05), except with the closest markers suggesting the absence of a signature of negative frequency dependent selection at the S-locus. Analysis of SFB1 and SFB2 protein sequences allowed identifying the absence of some variable and hypervariable domains and the presence of additional α-helices at the C-termini. Molecular and evolutionary analysis of SFB nucleotide sequences showed a signature of purifying selection in SFB2, while the SFB1 seemed to evolve neutrally. Thus, our results show that the SFB2 allele diversified after P. persica and P. dulcis (almond) divergence, a period which is characterized by an important bottleneck, while SFB1 diversified at a transition time between the bottleneck and population expansion. ; This research was supported by the Tunisian "Ministère de l'Enseignement Supérieur et de la Recherche Scientifique" and "Ministerio de Economía y Competitividad—European Regional Development Fund, European Union (AGL2016-77267-R and PID2019-109566RB-I00). ; Peer reviewed