MECHANISMS OF COLD STRESS TOLERANCE RESPONSES IN RICE

We propose to use molecular, genetic, and bioinformatics approaches to identify strong-effect rice cold tolerance genes and molecular mechanisms to enhance chilling tolerance of commercially grown rice in the United States. Development of regionally adapted chillingtolerant rice varieties that can be planted a few weeks earlier in the USA will: (i) reduce the risk of poor stand establishment or seedling vigor; (ii) reduce costs through utilization of spring rains; and (iii) increase yield and improve grain quality by decreasing the time plants are growing in high-temperature mediated reductions in carbon fixation efficiency and the effect of high night temperature on grain quality. This will have a positive impact on ecology, because it will reduce water usage and pesticide applications during the growing season due to earlier planting and harvesting. To achieve these goals, we have the following objectives:(1) identify genetic pathways and central hub genes for varying cold tolerance response mechanisms as a basis for gene discovery; (2) fine-map cold tolerance quantitative trait loci (QTL) to prioritize candidate genes for functional validation; and (3) validate phenotypic effects of QTL and candidate genes across various genetic backgrounds.