Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/27/2004
Publication Date: 2/7/2005
Citation: Horvath, D.P., Anderson, J.V., Chao, W.S. 2005. Leafy spurge: a model plant for genomic analysis of bud dormancy and insect/herbicide resistance. [Abstract]. Weed Science Society of America. Page No. 117. Interpretive Summary: We are presenting data that supports the use of the perennial weed leafy spurge as a model plant for studying growth, development, and dormancy of underground adventitious root buds and plant-insect interactions. Leafy spurge has been the subject of a concerted effort for developing a number of molecular and genomics based tools including an EST database and microarrays. Leafy spurge has also been the focus of several research groups studying bud dormancy. The use and characterization of several different bio-control agents for controlling leafy spurge has also provided researchers with information on the genetics and ecology of spurge-insect interactions. Combined, the establishment of a diverse group of researchers along with the on-going development of powerful genomics based tools makes leafy spurge an ideal candidate for a model perennial weed.
Technical Abstract: Keywords: Model Plant, Perennial, Leafy Spurge, EST database, Microarray One of the greatest advances in plant science has been the designation and study of model plants. Having model plants provides researchers with information from interconnecting lines of study, and human and material resources to develop tools to expedite scientific discovery. Although model systems have benefited the weed science community by providing a greater understanding of plant physiology and genetics, the scientific gains have often precluded the analysis of traits that are of specific interest to the weed science community. Significant information and tools now exist to warrant leafy spurge as a model perennial weed. Leafy spurge is an aggressive perennial weed that infests uncultivated land throughout the Northern Great Plains. Like many perennials, it produces and maintains underground adventitious buds that re-grow each spring. These buds display para-, eco-, and endo-dormancy, and are relatively easy to grow, collect, and study. Clonal propagation of leafy spurge in the greenhouse is routine, and transformation protocols are being developed. Physiological and molecular studies have identified many signals and responses associated with dormancy control in leafy spurge. The genetic and physiological responses of leafy spurge to biotic and abiotic control measures have been partially characterized. The genome size of leafy spurge is estimated to be only about 3 times larger than Arabidopsis. Numerous cDNA libraries are available for leafy spurge including: a two-hybrid library developed from 3 day induced growing buds; a normalized whole plant library that includes tissue from greenhouse and field grown plants, and plants stressed by disease, insect predation, and environmental extremes; and subtracted libraries developed from growing and dormant buds. In addition, a high quality genomic library has been constructed for leafy spurge. Development of an EST database is underway for the whole plant normalized library with nearly 5,000 unigenes to date. DNA microarrays will be constructed using long-oligo technology after 10,000+ unigenes have been identified. Initial cDNA Microarrays, developed from a small EST-database derived from the 3 day induced growing bud library, were successfully used to identify differentially expressed genes in buds during various stages of dormancy and growth.