[01] Ujjawal Kumar Singh Kushwaha, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [02] Vikas Mangal, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [03] Anil Kumar Bairwa, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [04] Sneha Adhikari, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [05] Tabassum Ahmed, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [06] Pallavi Bhat, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [07] Ankit Yadav, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [08] Narendra Dhaka, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [09] Deepak Raj Prajapati, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [10] Amit Kumar Gaur, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [11] Ranjana Tamta, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [12] Indra Deo, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India. [13] Narendra Kumar Singh, Department of Genetics and Plant Breeding, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttrakhand, India.

Association mapping is a powerful tool for the dissection of complex agronomic traits and for the identification of alleles. It is a very efficient and effective method for confirming candidate genes or for identifying new genes. Association mapping is a useful alternative to standard QTL mapping approaches which involves the correlation of molecular polymorphisms with phenotypic variation in a diverse assemblage of individuals. The comparatively high-resolution provided by association mapping is based on the structure of linkage disequilibrium (LD) across the genome. Many factors adversly affects association mapping, including population structure, small sample size, and low frequency of specific alleles that may increase the detection of a false positive associations. Association mapping offers great potential to enhance crop genetic improvement. Still extensive research is needed to understand the expansive application of association mapping. This review describes association mapping in detail along with its principles, techniques and application.

Association Mapping, Linkage Disequilibrium, Population Size, Crop Improvement, Alleles

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