Association mapping: A step forward to discovering new alleles for crop improvement

Understanding the basis of complex quantitative traits of economic importance is a major tactic behind the whole progress in plant breeding. Reading variation in phenotypes in the form of changes in DNA sequence and their location in the genome has been, traditionally, performed using linkage mapping, where crosses are made to develop a family with known parentage followed by identification of genetic markers co-segregating with target traits within this family. During the past decade, association mapping, commonly applied in human genetics, has shown greater promise and power of mapping complex quantitative traits in plants as compared to traditional linkage mapping. The focus of this review is to provide plant breeding community with the basic concept, pros and cons along with a brief description of some pioneer and recent reports to reveal the feasibility, achievements and future prospects of association mapping in plant genetics. The review would be useful for students and professional scientists working in the field of plant sciences to recognize the applications of this new approach and utilize in crop improvement programs both in academia and research.