Abstract

ARAUJO, LEILA G.  and  PRABHU, ANNE S.. Progress of leaf blast and other agronomic characteristics in advanced generations of aromatic somaclones of rice cultivar IAC 47. Fitopatol. bras. [online]. 2001, vol.26, n.3, pp. 606-613. ISSN 0100-4158.  http://dx.doi.org/10.1590/S0100-41582001000300005.

Field trials were conducted over three seasons with somaclones derived from the upland rice (Oriza sativa) cultivar IAC 47. Variation for rice blast resistance and other agronomic traits were assessed in the advanced generations of R₅, R₆, and R₇. The slow blasting resistance was evaluated based on the area under disease progress curve (AUDPC) and apparent infection rate (r). The correlations between R₆ and R₇ generations in relation to AUDPC as well as r were positive and highly significant. Somaclones also showed two distinct plant types, one with erect bright green leaves and other with droopy yellow green leaves different from the plant type of cultivar IAC 47 which is characterized by droopy pale green leaves. All somaclones exhibited aromatic grain characteristic. Somaclones also showed variation in grain type, height, growth duration, panicle grain weight and grain yield. Two somaclones SCIA02 and SCIA06 were identified that showed slow blasting resistance, early growth duration, and high yield potential compared to the parent cultivar IAC 47 besides the aromatic grain characteristic and plant type with erect bright green leaves. They can be used as new blast resistant sources for upland rice improvement.

Keywords : cultura de tecidos; epidemiologia; Oryza sativa; Pyricularia grisea.