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Embrapa has led breeding programs for irrigated and upland rice (Oryza sativa L.) since 1977, generating a large amount of pedigree and phenotypic data. However, there were no systematic standards for data recording nor long-term data preservation and reuse strategies. With the new aim of making data reuse practical, we recovered all data available and structured it into the Embrapa Rice Breeding Dataset (ERBD). In its current version, the ERBD includes 20,504 crosses involving 9,974 parents, the pedigrees of most of the 4,532 inbred lines that took part in advanced field trials, and phenotypic data from 2,711 field trials (1,118 irrigated, 1,593 upland trials), representing 226,458 field plots. Those trials were conducted over 38 years (1982-2019), in 247 locations, in latitudes ranging from 3°N to 33°S. Phenotypic traits included grain yield, days to flowering, plant height, canopy lodging, and five important fungal diseases: leaf blast, panicle blast, brown spot, leaf scald, and grain discoloration. The total number of data points surpasses 1.27 million. Descriptive statistics were computed over the dataset, split by cropping systems (irrigated or upland). The mean heritability of grain yield was high for both systems, at around .7, whereas the mean coefficient of variation was 13.9% for irrigated trials and 18.7% for upland trials. The ERBD offers the possibility of conducting studies on different aspects of rice breeding and genetics, including genetic gain, G×E analysis, genome-wide association studies and genomic prediction. Made available in DSpace on 2021-11-30T12:00:26Z (GMT). No. of bitstreams: 1 cropscience-2021.pdf: 1682169 bytes, checksum: e47084fb3060926dd37ca8419b8936da (MD5) Previous issue date: 2021

The objective of this study was to estimate the results of the upland rice (Oryza sativa L.) breeding program conducted by the Brazilian Agricultural Research Corporation (Embrapa) and collaborators over the period of 1984 to 2009 covering 25 annual steps of improvement. The best lines generated by this program are evaluated in “value for cultivation and use (VCU) trials.” This study used data from 603 VCU trials conducted in seven Brazilian States. The group of lines entering VCU in each year was taken as a sample of the elite program in that year. Best linear unbiased estimates (BLUEs) of the means of groups were computed, and the regression of the BLUEs on years was taken as an estimate of the effi ciency of the breeding program. Traits studied were grain yield (GY), days to fl owering (DTF), and plant height (PH). For GY, three phases were described: from 1984 to 1992, the gain for GY was nonsignifi cant, from 1992 to 2002, the yearly gain was 15.7 kg ha −1 (0.53%), and from 2002 to 2009, the yearly gain was 45.0 kg.ha −1 (1.44%). No evidence of yield plateau was observed. There was a reduction of 0.25 d yr −1 in DTF and 0.52 cm yr −1 in PH, refl ecting the change from traditional to modern cultivars. Factors infl uencing the results of the breeding program in this period are discussed.