1a. Objectives (from AD-416):
1. Conserve and distribute maize genetic stocks and associated information, so that natural and induced allelic and chromosomal variations of maize, and descriptions of the latter, are readily available to the maize research community. 2. Genetically characterize maize genetic stocks and incorporate genotypic and phenotypic data into MaizeGDB to increase the stocks’ utility as genetic tools.
1b. Approach (from AD-416):
Our mission is to make natural and induced allelic and chromosomal variations available to the scientific community and to make information about the mutant collection available to researchers. The National Plant Germplasm System provides support to selected genetic stock centers having genetic resources of value to U.S. agricultural interests. The Maize Genetics Cooperation - Stock Center maintains important accessions of morphological and physiological markers, aneuploid material, translocations and inversions that are important tools in biological research. This project will increase the value of the stock collection as genetic tools and confirm the status of novel mutants discovered. Maize mutants have historically been used in gene discovery and will continue to be used in this way. New mapping tools in our collection will allow easier identification of genomic sequence underlying a phenotype. More recently, novel genes are being identified purely by sequence analyses. This will excel in the next few years with the recent release of the maize genome sequence and addition of reverse genetics resources to our collection. Identification of the functions for these newly identified genes can be determined by researchers with these new tools.
3. Progress Report:
7,396 maize seed samples were supplied in response to 450 requests. 153 requests were received from 27 foreign countries. Six acres of nursery were grown last summer. Seasonable spring weather allowed us to plant our crossing nurseries in a timely manner, and warmer than normal weather during the growing season accelerated our pollination season. There were sufficient stands for an adequate increase in most instances. However, during the height of our pollination season in early July, 100+ degree temperatures resulted in drastically reduced seed sets on certain critical days. Plantings were made of donated stocks. Approximately 250 families of M2 materials were grown to increase seed supplies and recover previously observed mutations. Also, 1,510 families M2 EMS materials were grown for adult plant observation and 419 families were screened in sand benches for seedling traits. There are also additional sequence indexed lines from the UniformMu project. Our curation tools were updated and improved. These tools input our public stock data directly into MaizeGDB to give maize scientists access to up-to-date information about our collection. The tools are also used for our internal database. Maintenance continues on our web site. We conducted allelism tests on several categories of mutants with similar effects on the corn plant and/or found to be located in a similar position on a chromosome. We identified additional mutant variants of some genes. In this manner, we hope to incorporate more stocks from our vast collection of uncharacterized (phenotype-only) mutants into the main collection of characterized mutants. These studies will enhance corn biological research and lead to agronomic improvements in this crop plant.
1. Further characterization of new corn mutants. It is useful to determine if traits of these mutants are due to defects in known genes, or if they are novel traits. We conducted allelism tests on several categories of mutants with similar effects on the corn plant and/or found to be located in a similar position on a chromosome. We identified additional mutant variants of some genes. In this manner, we hope to incorporate more stocks from our vast collection of uncharacterized (phenotype-only) mutants into the main collection of characterized mutants. This will enhance corn biological research and lead to agronomic improvements in this crop plant.