Recently, heat stress is a major factor limiting rice production in
southern China. High temperature is detrimental to both the vegetative and reproductive stages of
rice[4]. The development of improved elite rice varieties with enhanced tolerance to high temperature
can help in solving this problem. Temperature higher than 35℃ for more than three days during
reproductive stages can affect the pollen development and pollination and dramatically decrease the
seed setting and production. However, the molecular heat response mechanism in plants and important
food crops is still unknown. Two rice varieties, 996 and 4628 were found with significant difference in
high-temperature tolerance. The seed setting percentage of 996 and 4628 were 66.31% and 36.11%
respectively under seven days 37℃/30℃ high temperature treatment, while under natural field
condition were 81.55% and 79.32% respectively. In this report, using rice 44K oligo-array, we
performed transcriptome analysis to identify genes responsive to high temperature in the heat tolerant
cultivar 996 (Oryza sativa L. ssp. japonica) and try to elucidate the molecular response model to heat in
rice during young panicle development.