In this study, a 141 BC3F4 lines from across between the O. sativa cv. Milyang23 as there current parent, and O. glaberrima as the donor parent was used to identify favorable QTL alleles from O. glaberrima for yield and yield components.
To detect the introgressions, 198 microsatellite markers of known chromosomal position were used for the parental survey. Of the 178 markers, 128 (64.6%) showed polymorphism. Among them, 115 SSR markers were used to construct a genetic linkage map with average interval length of 12.7 cM based on the previous rice molecular genetic map. The mean number of O. glaberrima segments in the population was 1.84 ranging from 0 to 7. The average length of the segments was 16.6 cM and ranged from 0.5 to 232.5 cM.
This population consisting of 141 lines was used to evaluate for six traits of agronomic importance and genotypes were determined for 141 BC3F5 using SSR markers. A total of 22 QTLs for 6 traits were detected on chromosomes 1, 2, 3, 4, 5, 6, 7 and 9. Phenotypic variance associated with each QTL ranged 9.5% ~ 58.2%. For 26 of the QTLs identified in this study, the O. glaberrima alleles contributed a desirable agronomic effect despite the over all undesirable characteristics of the wild phenotype. Favorable wild alleles were detected for culm length, panicle length, yield, panicles per plant and 1000-grain weight. When compared with previous studies involving interspecific crosses, it can be concluded that O. glaberrima is useful asa source of valuable alleles for rice improvement. There sults will be discussed.
Aluminum (Al) toxicity in plants is one of the major limitations to crop growth on acid soils. The Al-induced change of H+-ATPase expression has been regarded as an important mechanism for Al tolerance in soybean. To investigate whether translational regulation of plasma membrane H+-ATPase is involved in the response to Al stress, we conducted western - blot of this protein. The results show that western - blot of plasma membrane H+-ATPase in the "Sowon" (Al tolernace) significantly increased in translational expression level, while citric acid (50 μM) with Al (50 μM) treatment has not effected. In contrast, Al sensitive cultivar "Poongsannamool" inhibited expression level of plasma membrane H+-ATPase with Al treatment. Two - dimensional gel analysis were performed to determine the protein induction patterns of control and Al (50 μM, 24 h) treated soybean. There are many changes of plasma membrane proteins in both cultivars under Al stress. Especially "Sowon" was significantly enhanced the expression of the plasma membrane H+-ATPase in Al treatment. But protein expression of "Poongsannamool" was less than "Sowon". These results suggest that the regulatory role of plasma membrane H+-ATPase may involved the tolerance mechanism in soybean roots. At the present, transcriptional level of H+-ATPase is under investigation.