Development of Maize DNA Markers
Development of DNA Markers in Maize for Genetic Diversity Assessment and Plant Breeding Applications
Tech Area / Field
- AGR-PPR/Plant Protection/Agriculture
- BIO-CGM/Cytology, Genetics and Molecular Biology/Biotechnology
3 Approved without Funding
Institute of Molecular Biology and Biophysics, Georgia, Tbilisi
- Ohio State University / USDA-ARS Laboratory, USA, OH, Columbus
Project summaryThe purpose of the proposed work is to investigate random amplified polymorphic DNA (RAPD) variation from seeds of differing Georgian maize genotypes and to study phylogenetic relationships between maize varieties or between cultivars within varieties. RAPD analysis is recently developed molecular technique, which is currently available in the crop sector. It is widely used to study and to search for markers of plant genome. RAPDs have important applications in plant breeding, seed and food production, and seed testing programs, especially in cultivar identification and certification. Therefore, the development of new RAPD markers for crop cultivars is of particular interest.
RAPD is an example of polymerase chain reaction (PCR)-based techniques. PCR is applied for investigation of a wide range of species, from microorganisms to humans. In our previous studies we have successfully used PCR for cloning and sequencing of archaebacterial DNA polymerase-encoding gene, for amplification of bacterial chromosomal gyr promotor regions, and for amplification of aspen isoprene synthase gene fragments.
Maize (Zea mays L.) is an important cereal crop in the world. It is used as a human food, a feed grain, a fodder crop, and for various industrial purposes. Maize is a versatile crop and has tremendous genetic variability, which enables it to grow well in different climates. Four groups of maize thrive in Georgia: Z.m. indurata Montg., Z.m. indentata Sturt., Z.m. Semidentata Kulesh., and Z.m. everta Sturt. There are 2 varieties (var. Alba Al., var. vulgata Koern), 11 local cultivars of Z.m indurata Montg., and 3 varieties (var. lencodon Al., var.xantodon Al., var. pyrodon Al.) and 7 local cultivars of Z.m. indentata Sturt, grown in different parts of Georgia. The proposed project will provide information on the molecular basis of genetic persity and of phylogenetic relationships among Georgian maize cultivars. This information would be useful for the study of the plant genetic fund and could be used in practice for maize production, seed testing, cultivar identification and agriculture.
There are a number of studies indicating that RAPD technology is successfully used for investigation of seeds from different American maize genotypes, American maize accessions of the Great Plains, and early European maize inbreeds.
How does one identify RAPD markers for Georgian maize cultivars? To answer this question, first of all, DNA extraction from dry seeds of each cultivar is planned in proposed project. Based on available data on primer sequences, useful for detection of DNA polymorphism in maize, a number of arbitrary, 10-mer primers will be selected and screened to amplify all the genotypes. Optimum PCR conditions will be set up for each primer. Primers given reproducible, polymorphic DNA amplification patterns will be selected for the study. RAPD markers will be determined for the identification of each maize cultivar. Amplification products, generated from genomic DNA of maize cultivars using arbitrary primers, will be observed by agarose gel electrophoresis. A test protocol will be standardized for each cultivar. RAPD profiles will be used to detect the genetic variability and to quantify the level of polymorphism among studied maize cultivars. A phylogenetic dendrogram will be constructed by cluster analysis (UPGMA - Unweighted Pair-Group Methods).
The following major results will be obtained:
1. Identification and characterization of new DNA markers for maize.
2. Development of new standard DNA-tests for identification of Georgian maize cultivars.
3. Certification of Georgian maize cultivars.
4. Assessment of genetic persity in maize cultivars.
5. Selection of the genetic pairs generating high productive hetero-hybrids for maize-breeding application.
6. Obtaining new insights in the phylogenetic relationships among maize varieties and cultivars.
7. Provision of suggestions and recommendations for seed companies and farmers interested in seed testing, cultivar identification, and plant breeding.
Successful project completion will facilitate the future development of research in this field, particularly concerning the use of identified DNA markers for quantitative trait loci identification.
The project will be carried out in close collaboration with US scientists from the USDA-ARS Lab at Ohio State University.