Awards issued prior to january 20, 2025, were funded under previous administrations and may not reflect the priorities and policies of the current administration.** the goal of this project is to…

Awards issued prior to january 20, 2025, were funded under previous administrations and may not reflect the priorities and policies of the current administration.** the goal of this project is to produce rice plants with stable and long-lived herbicide resistance traits. Weeds can gain herbicide resistance by receiving pollen from crop plants and acquiring resistance genes directly. Such weeds are tremendous problems, especially for rice farmers in the southern US states as well as in asia, latin america and europe. This weedy rice problem is eroding the efficacy of herbicides resulting in significant gain yield losses. Consequently, IT is highly desirable to produce crop plants that cannot transmit herbicide resistance through pollen. Such crop plants are not available currently; however, the new technology we develop at napigen will provide a means for their development. We previously have developed technologies for gene editing of plant mitochondrial DNA, a goal that had eluded plant scientists for decades. Therefore, we can introduce an herbicide resistance gene into the mitochondrial genome. Since mitochondria are maternally inherited, the mitochondrial herbicide resistance gene will not be transmitted by outcrossing to weed plants. Unlike nuclear DNA, plant cells can have hundreds of copies of mitochondrial DNA. A current challenge is ensuring that engineered mitochondrial DNA is the dominant form in a transformed plant cell. In this project, we propose selection methods to increase the proportion of engineered mitochondrial DNA having an herbicide resistance gene derived from rice itself. The resulting plants will not have any exogenous genes from other species, accommodating public preference regarding gene edited products. The technology obtained from this project can be used to develop other novel mitochondrial traits in crop plants such as cytoplasmic male sterility for hybrid seed production, improved nitrogen use efficiency, and enhanced drought tolerance, each of which would increase crop yields under normal as well as stressful conditions worsen by climate change.