Diploid potato breeding: a new proposal for tropical potato crop in Brazil

• Grant number: 22/03224-6
• Support Opportunities: Research Grants - Initial Project
• Start date: February 01, 2023
• End date: January 31, 2028
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Fernando Angelo Piotto
• Grantee: Fernando Angelo Piotto
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated scholarship(s): 23/02478-7 - Obtaining and characterizing diploid potato progenies for heat tolerance., BP.DR; 23/02479-3 - Phenotypic variability, genetic diversity and association mapping in potatoes to heat tolerance traits, BP.DR

Abstract

Potato (Solanum tuberosum L.) is the third most important food plant species in the world, presenting tetraploidy (2n = 4x = 48) as a genetic characteristic, gametophytic self-incompatibility and vegetative propagation from tubers. In this sense, the process of obtaining, evaluating, selecting and recombining progenies for the development of new cultivars is quite difficult due to these characteristics. In Brazil, more than 90% of potato cultivars grown on national soil come from other countries, having greater adaptation to cultivation in colder climate conditions. In our country, there is no motivation from the private sector to study and develop new potato cultivars that are adapted to growing conditions in tropical and sub-tropical climates. Such an approach is only able to prosper at the moment, through public sector efforts. Despite several adaptations in the methods of selection and improvement of the crop, the development of new cultivars of tetraploid potato can take up to 12 years, being expensive and costly. For this reason, our proposal is to develop an unprecedented strategy for the improvement of potatoes for cultivation in tropical climate conditions in Brazil, aiming mainly at heat tolerance, through the creation of a breeding program for diploid potatoes, to enable their propagation. and cultivation from botanical seeds, making our research group a pioneer in the development of new diploid potato cultivars in Brazil. Thus, the objective of this project is to obtain and characterize diploid (or diaploid) potato plants, from crosses with heat-tolerant tetraploid clones, selected through experiments carried out at different times. To this end, our panel of potato accessions will be phenotypically characterized for heat tolerance (at the beginning and end of the cultural cycle) and for other traits, and also genotyped to carry out studies of diversity, genetic structure and also mapping by association for several characteristics. Based on these data, the best clones will be selected to obtain diploid plants, via dihaploidy, and the consolidation of studies and the beginning of an unprecedented program for the improvement of diploid potatoes in Brazil. Such an approach is innovative and should provide the consolidation of a research line at the University of São Paulo, generating innovative results in scientific terms, but also in practical terms, being able to generate highly relevant impacts for the national potato production chain, in the medium and long term. (AU)