S01 - Session P2 - Using genomic selection to predict heat-tolerant tomato accessions

Authors: Le Kang *, Shin-Ruei Lee

In order to pre-screen 4000 tomato accessions without phenotype data more effectively, 290 core collection accessions representing the entire germplasm were chosen to develop a model for genomic selection. The accessions were evaluated for yield, fruit weight and soluble solids concentration (SSC) in soilless cultivation in a glasshouse with high temperature conditions. The phenotypic data and the genomic information were used to train the prediction model. Therefore, we could apply it with genome-wide genotypes to calculate the genomic estimated breeding value (GEBV) of 4,000 tomato accessions held at the National Plant Genetic Resources Center of the Taiwan Agricultural Research Institute. To verify the effectiveness of the method, some accessions were selected for a correlation analysis of the GEBV and actual observations. The results showed that the squared correlation (R2) of yield, fruit weight and SSC were 0.126, 0.252 and 0.173, respectively. Although those were lower than the R2 values (0.464, 0.450 and 0.194) of the same accessions' performance in different years, it still shows the ability to increase the efficiency of selecting heat-tolerant accessions.