Effect of low-Tw treatment before panicle initiation on the chilling response of spikelets at the booting stage in rice.

ABSTRACT: 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.

ORGANISM(S): Oryza sativa

SUBMITTER: Kensaku Suzuki 

PROVIDER: E-GEOD-59221 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress