01949naa a2200277 a 450000100080000000500110000800800410001902200140006010000220007424501040009626000090020052011630020965000180137265000330139065000090142365000190143265000100145165000120146165000220147365000170149565000230151265000230153570000180155870000180157677300770159412053172020-10-06       1998    bl uuuu     u00u1 u    #d  a0100-204X1 aARAÚJO, L. G. de  aVariation for rice blast resistance in early somaclonal generations derived from immature panicles.  c1998  aSomaclones derived from immature panicles of the rice cultivars Bluebelle and Maratellisusceptible to blast and their F1?s from crosses with resistant donors (Araguaia, Basmati-370 andRamtulasi) were compared in the R2 (plants from self-pollinated seed from primary R1 regenerants) and R3generations in the greenhouse and field for blast resistance. In the greenhouse the R2 plants and R3 lineswere inoculated with the races IB-1 and IB-9 of Pyricularia grisea. The frequency of plants resistant toboth races ranged from 16 to 42% in the F1 derived somaclones, whereas no resistant plant was recoveredfrom the susceptible parents when inoculated with IB-1. The means of the leaf blast rating of R2 and R3populations of F1?s were significantly lower than those derived from susceptible parents. Similar resultswere obtained in field trials. However, the performance of the F1 derived somaclones varied depending onthe resistant donor parent. In field trials, the mean visual ratings for leaf blast of regenerants from F1derived R2 and R3 populations were significantly lower than those regenerants derived from the parentalgenotypes Maratelli and Basmati-370.  aBlast disease  aPlant diseases and disorders  arice  atissue culture  aArroz  aBrusone  aCultura de Tecido  aOryza Sativa  aPyricularia Grisea  aPyricularia Oryzae1 aPRABHU, A. S.1 aFREIRE, A. B.  tPesquisa Agropecuária Brasileiragv. 33, n. 8, p. 1349-1359, ago. 1998.