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Genebanks, other than their pivotal role as diversity conservation repositories, regenerate part of their collection every year to maintain their material in optimal conditions. During regeneration cycles, morpho-physiological data are collected, contributing to the creation of large datasets that offer a valuable resource of information. In Italy, rice cultivation has been documented since the second half of the 15th century, and nowadays, Italy contributes more than 50% of the total European rice production. The ex situ collection of rice (mainly Oryza sativa L. subgroup japonica) held at the Research Center for Cereal and Industrial Crops (CREA-CI) of Vercelli is quite unique in Italy and its establishment dates back to the beginning of the 20th century. The collection is hereby presented through the analysis of 21 years of historic data, from 2001 to 2022, in 17 different locations in Northern Italy, for a total of 6592 entries, 677 genotypes analyzed and 9 phenotypic traits under investigation. An R script has been developed to analyze the dataset. The BLUEs calculation, heritability, PCA and correlation with weather data provided a comprehensive overview of the germplasm stored in the genebank. The great variability and phenotypic diversity were assessed, key aspects from the perspective of breeding programs. This work starts a re-evaluation of historic data, historic cultivars, and represents the first step toward the shift of the genebank to a bio-digital resource center.

Rice blast, caused by Pyricularia oryzae, is one of the main rice diseases worldwide. The pyramiding of blast-resistance (Pi) genes, coupled to Marker-Assisted BackCrossing (MABC), provides broad-spectrum and potentially durable resistance while limiting the donor genome in the background of an elite cultivar. In this work, MABC coupled to foreground and background selections based on KASP marker assays has been applied to introgress four Pi genes (Piz, Pib, Pita, and Pik) in a renowned japonica Italian rice variety, highly susceptible to blast. Molecular analyses on the backcross (BC) lines highlighted the presence of an additional blast-resistance gene, the Pita-linked Pita2/Ptr gene, therefore increasing the number of blast-resistance introgressed genes to five. The recurrent genome was recovered up to 95.65%. Several lines carrying four (including Pita2) Pi genes with high recovery percentage levels were also obtained. Phenotypic evaluations confirmed the effectiveness of the pyramided lines against multivirulent strains, which also had broad patterns of resistance in comparison to those expected based on the pyramided Pi genes. The developed blast-resistant japonica lines represent useful donors of multiple blast-resistance genes for future rice-breeding programs related to the japonica group.