Project description:In rice (Oryza sativa L.), chilling-induced male sterility increased when plants experienced low water temperature (Tw, 18 °C for 14 days) before panicle initiation. The number of mature pollen grains after chilling at the booting stage (12 °C for 5 days) was only approximately 45% of total pollen grains in low-Tw plants, whereas it was approximately 71% in normal-Tw plants (Tw not controlled; approximately 23 °C under air temperature of 26 °C/21 °C, day/night). Microarray and quantitative PCR analyses showed that many stress-responsive genes (including OsFKBP65 and genes encoding a large heat shock protein OsHSP90.1, heat-stress transcription factors, and many small heat shock proteins) were strongly up-regulated by chilling in normal-Tw spikelets, but were not or rather down-regulated by chilling in low Tw spikelets. OsAPX2 and genes encoding some other antioxidative enzymes were also significantly down-regulated by low Tw in the chilled spikelets. In low-Tw plants, lipid peroxidation products (malondialdehyde equivalents) were significantly increased in the spikelets after chilling, and ascorbate peroxidase activity in the chilled spikelets was significantly lower than that in normal-Tw plants. Our data suggest that an OsFKBP65-related chilling response, which protects proteins from oxidative damage, is indispensable for chilling tolerance but is lost in low-Tw spikelets.
Project description:In rice (Oryza sativa L.), chilling-induced male sterility increased when plants experienced low water temperature (Tw, 18 M-BM-0C for 14 days) before panicle initiation. The number of mature pollen grains after chilling at the booting stage (12 M-BM-0C for 5 days) was only approximately 45% of total pollen grains in low-Tw plants, whereas it was approximately 71% in normal-Tw plants (Tw not controlled; approximately 23 M-BM-0C under air temperature of 26 M-BM-0C/21 M-BM-0C, day/night). Microarray and quantitative PCR analyses showed that many stress-responsive genes (including OsFKBP65 and genes encoding a large heat shock protein OsHSP90.1, heat shock factors, and many small heat shock proteins) were strongly up-regulated by chilling in normal-Tw spikelets, but were not or rather down-regulated by chilling in low Tw spikelets. OsAPX2 and genes encoding some other antioxidative enzymes were also significantly down-regulated by low Tw in the chilled spikelets. In low-Tw plants, lipid peroxidation products (malondialdehyde equivalents) were significantly increased in the spikelets after chilling, and ascorbate peroxidase activity in the chilled spikelets was significantly lower than that in normal-Tw plants. Our data suggest that an OsFKBP65-related chilling response, which protects proteins from oxidative damage, is indispensable for chilling tolerance but is lost in low-Tw spikelets. Four conditions used: low Tw and chilled, low Tw and not chilled, normal Tw and chilled, normal Tw and not chilled, before panicle initiation and at the booting stage, respectively. Biological replicates: 4 for each treatment.
Project description:To understand how the qDTY12.1 interacts with other genes within the genome to give better yield under drought; the spikelets transcriptome of DTY12.1 parents (Vandana , Way Rarem) and DTY12.1 NIL (481-B) were compared under control and drought conditions.
Project description:To understand how the qDTY12.1 interacts with other genes within the genome to give better yield under drought; the spikelets transcriptome of DTY12.1 parents (Vandana , Way Rarem) and DTY12.1 NIL (481-B) were compared under control and drought conditions. Drought induced gene expression was studied in the spikelets of the rice plants subjected to severe reproductive stage drought. Seeds of Vandana, Way Rarem, and 481-B were sown into rotovated soil at a rate of 2.0 g m-1 into plots of 3 rows X 3 m. The three genotypes were sown in three replications in a randomized complete block design.