Prediction and Expression Analysis of miRNAs Associated with Heat Stress in Oryza sativa

Computational prediction of potential microRNAs （miRNAs） and their target genes was performed to identify the miRNAs and genes associated with temperature response in rice. The data of temperature-responsive miRNAs of Arabidopsis, and miRNAs and the whole genome data of rice were used to predict potential miRNAs in Oryza sativa involved in temperature response. A total of 55 miRNAs were common in both the species, and 27 miRNAs were predicted at the first time in rice. Target genes were searched for these 27 miRNAs in rice genome following stringent criteria. Real time PCR based on expression analysis of nine miRNAs showed that majority of the miRNAs were down regulated under heat stress for rice cultivar Nagina 22. Furthermore, miR169, miR1884 and miR160 showed differential expression in root and shoot tissues of rice. Identification and expression studies of miRNAs during heat stress will advance the understanding of gene regulation under stress in rice.     

Molecular Mapping of QTLs for Yield and Yield-Related Traits in Oryza sativa cv Swarna × O. nivara (IRGC81848) Backcross Population

Advanced backcross QTL analysis was used to identify QTLs for seven yield and yield-related traits in a BC2F2 population from the cross between a popular Oryza sativa cv Swarna and O. nivara IRGC81848. Transgressive segregants with more than 15% increased effect over Swarna were observed for all the traits except days to heading and days to 50% flowering. Thirty QTLs were detected for seven yield and yield-related traits using interval and composite interval mapping. Enhancing alleles at 13 (45%) of these Q...