Indian Journal of Plant Genetic Resources

Allium germplasm harbour novel genes which could be utilized in breeding programme for developing elite cultivars. Availability of wide genetic variability and its comprehensive knowledge is an important step towards the development of improved varieties in different cultivated alliums. Earlier, Allium germplasm characterized based on morphological markers but they are affected by environment and plant development stages which leads to biased estimates of variability. In various crop plants different molecular markers are utilized for diversity studies due to their unbiased nature and neutrality with no environmental effect. Also in genus Allium various marker systems such as isozymes, Random Amplified Polymorphic DNA (RAPD), Amplified Fragment Length Polymorphism (AFLP) and Restriction Fragment Length Polymorphism (RFLP) were used but they show number of disadvantages. To overcome their drawbacks, Simple Sequence Repeat (SSR) markers were developed in Allium cepa, A. fistulosum and A. sativum which are being utilized for DNA fingerprinting, genetic diversity analysis and cross amplification studies for better understanding of Allium germplasm. In future it will be desirable to use microsatellite markers for developing high density linkage map to follow marker assisted selection. Further understanding of population structure would be beneficial to exploit natural variation by using association mapping.