Varietal differences in lodging resistance of African rice (Oryza glaberrima Steud.)

Abstract

To identify resistant genotypes to lodging in African rice (Oryza glaberrima), 6 genotypes, three of which were selected by prescreening for the resistance and the remaining three were used in an interspecific breeding program at WARDA, were tested in terms of resistance to lodging. The trial was conducted in rainfed upland in 2005 and in irrigated lowland in 2006 and all genotypes showed higher yield and larger plant length in 2006 than in 2005. There was a clear varietal difference in lodging incidence of the O. glaberrima genotypes at maturity, which was ranged from 0.0 to 91.0% and from 68.6 to 99.7% in 2005 and 2006, respectively. In 2005, four O. glaberrima genotypes, TOG 7235, IRGC Accession Code 104038, CG 14 and CG 20, depicted the resistance at maturity since their lodging incidences were from 0.0 to 6.7%. With heavier panicles by higher yield and larger plant length in 2006, however, two of those four genotypes almost completely lodged at maturity. The remaining two genotypes, TOG 7235 and CG 14, showed moderately low lodging incidences of 74.1 and 68.6%, respectively. However, those rates are still very high as a commercial variety and further screening for lodging resistance is necessary. © 2008 Asian Network for Scientific Information.