Resumo

TORREALBA, Gelis et al. Somaclonal variation of six rice genotypes. Agronomía Trop. [online]. 2006, vol.56, n.4, pp.585-591. ISSN 0002-192X.

The objective of this research was Somaclones of six genotypes of rice, Oryza sativa L., to improve some agronomic and grain quality characteristicof the following breeding lines: “CIMARRÓN”, “CT10310-15-3-2P-4-3”, “CT10338-16-1-1-1T”, “CT9682-2-M-14-1-M-1-3P-M”, “CT9868-3-2-31-4P-M-1-3P” and “CT9509-17-3-1-1-M-1-3P-M-3-3P”. Of 41 somaclones evaluated, three CT10310-15-3-2P-4-3 somaclones were found to have better grain quality, white belly reduction and decreased endosperm chalkiness and one somaclone, also showed lower panicle sterility when evaluated in INIA Guárico. Molecular differentiation was performed at the Biotechnology Laboratory of INIA-CENIAP, using random amplified polymorphism DNA (RAPDs). Gelatinization temperature of CT9868-3-23-1-4P-M-1-3P improved, changing from low to medium. Four somaclones of CIMARRON showed reduced hoja blanca virus infection, from 75% infection in the check to a maximum of 30% of infection in the somaclones. Some somaclones derived from CT10338-16-1-1-1T showed intermediate reaction to direct damage caused by the brown plant hopper (Tagosodes orizicolus), no one was found to be completely resistant. About 92.47% of CT9682-2-M-14-1-M-1-3P-M somaclones were resistant to hoja blanca virus. Somaclones from CT9509-17-3-1-1-M-1-3P-M-3-3P evaluated in INIA-Portuguesa had an inferior agronomic behavior.

Palavras-chave : Rice; Oryza sativa L; somaclone; RAPDs.