Obtaining and characterizing diploid potato progenies for heat tolerance.

• Grant number: 23/02478-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): April 01, 2023
• Effective date (End): February 28, 2026
• Field of knowledge: Agronomical Sciences - Agronomy
• Principal Investigator: Fernando Angelo Piotto
• Grantee: Gustavo Nandi
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 22/03224-6 - Diploid potato breeding: a new proposal for tropical potato crop in Brazil, AP.PNGP.PI

Abstract

Potato (Solanum tuberosum L.) is a tetraploid species (2n =4x = 48) presenting gametophytic self-incompatibility and propagation by tubers. Geneticgains in breeding programs are severely reduced due to the labor-intensive and time-consuming process for obtaining, evaluating, selecting and recombining progenies. Despite several recurrent selection adaptations - most common breeding method in the crop - only one selection cycle using tuber-propagation in tetraploid potato can take up to 10 years, discouraging the search for new cultivars. Given that, innovative approaches must be proposed as an alternative for the reformulation of potatoes as a diploid crop, through research with diploid (or di-haploids) inducers and sources of self-compatibility. Among the benefits of this reinvention, we can highlight propagation, genetic studies, phenotypic evaluation, transport and storage as the main processes that can be positively altered. In order to meet the countless requirements of the agricultural/industrial sector, registration of superior clones requires extensive phenotypic evaluations. Several trials in many year/locations are needed to improve the chance to select the best clones intended to each specific market segment (in natura, french-fries, chips). Therefore, several characterization studies are necessary for attributes such as productivity, tuber shape and color, dry matter content, flavor, browning after frying, quality after storage (Cold Induced Sweetening), incidence of physiological defects, resistance against pathogens, and other agronomic traits. Assisted by molecular tools such as genomic selection (SG) and genome-wide association mapping (GWAS), selection gain may be substantially sped up, since several cycles of evaluation and phenotypic selection can be reduced. These tools allow breeders to get better estimates of the genetic value (breeding value) and to find genomic regions associated withdesirable agronomic traits using advanced statistical techniques, reducingphenotyping costs and extensive field trials, since it is possible to select individuals based only on genotypic data, obtain more reliable estimates of heritability and variance components and also enable prediction of crosses and selection of parents.