ABSTRACT
To improve the blast resistance of elite rice restorer line Fuhui 673, 3 blast resistance genes Pi-1, Pi-9 and Pi-kh were introduced into Fuhui 673 from a good-quality restorer line Jinhui 1059 through 3 successive backcrosses followed by one selfing using the technique of marker-assisted selection. Ten near-isogenic lines (NILs) of Fuhui 673 carrying the 3 introduced resistance genes were created. Genotype analysis using 68 SSR markers evenly distributed in the genome indicated that 92.96%-98.59% of the NILs' genetic background had been recovered to Fuhui 673. Both indoor and field resistance tests indicated that the NILs and their hybrids with sterile line Yixiang A were all resistant to rice blast, with resistance levels significantly higher than those of controls Fuhui 673 and hybrid Yiyou 673 (Yixiang A Fuhui 673). In addition, among the 10 hybrids between the NILs and Yixiang A, 2 showed significantly higher yield than and 4 displayed similar yield to that of control Yiyou 673, suggesting that most of the NILs retained the elite characteristics of Fuhui 673. Two new hybrid rice cultivars Liangyou 7283 and Jintaiyou 683 from NIL Line 9 showed high yield, good resistance to blast and moderate growth period in regional trial, suggesting that the NIL Line 9 has a good prospect for application.
Subject(s)
Breeding , Disease Resistance , Genetics , Genes, Plant , Genetics , Oryza , GeneticsABSTRACT
The effects of GPA, anti-GPA IgG, ?1acid glycoprotcin (?1-AGP), ovomucoid (OM) and wheat germ agglutinin (WGA) on the invasion of erythrocytes by P. falciparum were obseryed in vitro. GPA, anti-GPA IgG and WGA at low concentrations had obviously inhibitory effects on thc invasion. There were hyperbolic relationships between the concentrations of these inhibitors and their inhibition rates. OM, ?1-AGP and non-spccific anti-serum had no obvious effect on the invasion. It is confirmed for the first time from the biological characteristics of receptor-ligand interaction that thc combination of GPA with P. falciparum merozoites has high spccificity, high affinity with a tendency to sa-turation and can produce specific biological effects.