CR 741 A NEW RICE (ORIZA SATIVA) CULTIVAR IN ENTRE RIOS, ARGENTINA

COLAZO, J.L.; BALZARINI M.; DURAND, M

Simposio; Primer Simposio de Mejoramiento Genético Vegetal; 2021

Irrigated rice cultivation is considered a regional economy in Entre Rios, Argentina, generating employment, adding value to agricultural production, and capturing foreign exchange. Nowadays, the high cost of energy associated with rice irrigation impact strongly in the crop profitability. The length of the crop cycle of each cultivar becomes important due to its economic impact, and also environmental issues (water footprints). Focus on this issue, INTA rice-breeding program began to select genetic with shorter cycles, maintaining the potential productivity and grain quality, a hallmark of Argentinian rice varieties. Rice cultivars registration demands validation of advanced experimental lines in multi-environmental trials regarding broad agronomic performance (overall yield), site-specific adaptations, and yield stability across environments. The objective of this work was to evaluate advanced experimental lines of the INTA rice-breeding program in terms of yield and precocity. Fourteen genotypes (seven advanced lines and seven commercial cultivars of broad adaptation) were evaluated in four locations during three years. The variance components were estimated using the REML method. Genotype (G) and genotype-by-environment interaction (GE) effects were explored via a GGE biplot analysis. The stability of each genotype was quantified through linear regression of yields on the environmental yield means using InfoGen software. Yield variability among environments (E), G, and GE combinations explained 29.5%, 21.6%, and 15.5% of the total variability in yield, respectively. The GGE analysis showed that the CR 741 line stood out positively in most of the environments evaluated. Furthermore, CR 741 showed good environmental adaptation in poor and rich environments, compared to the cultivar "GURI INTA CL?, which has outstanding performance in local production systems. The trait "days to flowering" (DF) was analyzed during five crop years at the experimental rice field INTA-Concepción del Uruguay. Data indicate a reduction of 4 ± 1 days in DF for the line CR 741 compared to GURI INTA CL. Modern varieties are insensitive to photoperiodic and depend on temperature for development. A reduction in DF will impact positively in saving water to obtain the same grain productivity. Dueto its average yield, its stability, and precocity of the cycle, the CR 741 line constitutes a promising rice cultivar.Besides its excellent agronomic performance, this line contains the Clearfield technology for weed control, has a slender grain with high-quality parameters, high amylose content, and low gelatinization temperature in grain being appropriate for rice production in Latin America.