Molecular Markers:A Tool for Improvement in Fruit Crops

Markers can be defined as heritable entities associated with the economically important trait under the control of polygenes. Markers are any trait of an organism that can be identified with confidence and relative easy, and can be followed in a mapping population. There are two types of genetic markers viz., morphological markers or naked eye polymorphism and non-morphological markers or molecular markers. Morphological markers include traits such as plant height, disease response, photoperiod, sensitivity, shape or colour of flowers, fruits or seeds etc. Molecular markers include biochemical constituents. Consequently, molecular markers could be appropriate choice to study and preserve the diversity in any germplasm. Molecular markers have diverse applications in fruit crop improvement, particularly in the areas of genetic diversity and varietal identification studies, gene tagging, disease diagnostics, pedigree analysis, hybrid detection, sex differentiation and marker assisted selection.