Detalle de: Seedless avocadoes and cherimoyas for a sustainable and differentiated quality production in Andalusia

In Europe, subtropical fruit production is concentrated along the Andalusian Mediterranean coast, where Spain is virtually the only country with significant commercial production. European avocado consumption continues to grow rapidly; however, an increasing number of countries with continuous production growth are entering the European market. Under these conditions, optimizing avocado production in Andalusia is more urgent than ever, and the future of the Spanish avocado relies on clear commercial differentiation relative to imported product. Unlike the avocado, cherimoya production is not growing and has been experiencing a slight decline in recent years, being primarily targeted for domestic consumption due to post-harvest handling difficulties and the added challenge of requiring manual pollination to obtain commercially viable yields. Both crops face the challenge of having a limited number of varieties, which threatens their medium-term sustainability. At the IHSM La Mayora, the avocado and cherimoya germplasm collections are essential for finding high-quality, sustainable varieties. The reduction or elimination of seeds is a major goal in breeding these varieties, and thanks to these collections, we have access to relevant plant material to study these processes. Avocados occasionally produce seedless fruits, known as "cukes" in the 'Fuerte' genotype. This is a case of stenospermocarpy, as pollination is required. At IHSM La Mayora, it has been observed that one of the genotypes in the collection is capable of recurrently producing over 90% of its fruits as seedless "cukes." Preliminary studies by this research group suggest that pollination is not required for fruit production in this genotype, which would make it a unique case of parthenocarpy in avocados. In cherimoya, a natural mutant called "Thai seedless" has been observed to produce seedless fruit requiring pollination, representing a case of stenospermocarpy. A new variety ('Guamoya') has also been incorporated, which produces seedless fruit in the absence of pollination, constituting a case of parthenocarpy. These genotypes represent an important innovation in the production of both fruit crops and allow for a comparative study of the mechanisms (parthenocarpy and stenospermocarpy) that account for seedlessness in both species. This project aims to investigate and develop seedless avocado and cherimoya varieties to optimize sustainable, high-quality production along the Andalusian Mediterranean coast. In avocados, parthenocarpy in this selected genotype and stenospermocarpy in the 'Fuerte' genotype will be evaluated. Their reproductive biology will be assessed, and an integrative comparative analysis of transcriptomics, genomics, and metabolomics will be conducted. In cherimoya, parthenocarpy in 'Guamoya' and stenospermocarpy in "Thai seedless" will also be studied using an approach similar to that of the avocado study. Furthermore, a genetic breeding program for both species will be continued to obtain seedless avocados and cherimoyas. In addition to the applied aspect of the project to obtain fruit with differentiated quality in subtropical fruit production, it is essential to consider the position of avocado and cherimoya among the most primitive angiosperms. Consequently, the results generated in these species will have a high impact on understanding the evolution of parthenocarpy and stenospermocarpy in angiosperms, and will also be significant for application to other fruit crops. This research will contribute to the proper management of these genotypes, enabling sustainable development while maintaining and enhancing Andalusia's leadership position in these crops within Europe.