Development of gene based markers for crop improvement

Rajesh Singh¹, Shiv Kuamr Agrawal²

¹Genetics and Plant Breeding, IAS, BHU, Varanasi-221005 (UP), India

²Lentil Breeder and Food Legumes Coordinator, ICARDA/Rabat Office, PO box 6299, Rabat-Institutes, Rabat 10112, Morocco

Received: 13 February 2016                             Revised Accepted: 10 April 2016

ABSTRACT

The advancement in biological research encompassing, generation of huge amount of molecular-genetic data, development of impressive methodological skills in molecular biology experimentation, and system and systems analyses, has set the stage to search for ways/means to utilize the available resources to strengthen interdisciplinary efforts to find solutions to the challenging goals in crop improvement. With the advent of molecular markers, a new generation of markers has been introduced over the last two and half decades, which has revolutionized the entire scenario of biological sciences. A positive fall out of such a realization and efforts has been the identification/development of a new class of very useful DNA markers called genic molecular markers (GMMs) utilizing the ever-increasing archives of gene sequence information being accumulated under the EST sequencing projects on a large number of plant species in the recent years. These markers being part of the cDNA/EST- sequences, are expected to represent the functional component of the genome i.e. gene(s) in contrast to all other random DNA-based markers (RDMs) that are developed/generated from the anonymous genomic DNA sequences/demonstrate large effects on adaptive plant behavior remains fundamental to the development of GMMs. DNA-based molecular markers have acted as versatile tools and have found their own position in various fields. They are no longer looked upon as simple DNA fingerprinting markers in variability studies or as mere forensic tools. Ever since their development, they are constantly being modified to enhance their utility and to bring about automation in the process of genome analysis. The discovery of PCR (polymerase chain reaction) was a landmark in this effort and proved to be a unique process that brought about a new class of DNA profiling markers. This facilitated the development of marker-based gene tags, map-based cloning of ergonomically important genes, variability studies, phylogenic analysis, synteny mapping, marker-assisted selection of desirable genotypes, etc.  In this article, genic/ functional  developed during the last two decades of molecular biology research and utilized for various applications in the area of plant genome analysis are reviewed.

Key Words: Gene based markers, Molecular markers, Plant breeding, Simple equnce repeat