Genetic Diversity Assessment in Cereal Crops

Human intervention in nature has severely affected climatic changes resulting in global warming which drastically influences the agriculture sector and crop yield is substantially hampered. Enhancing crop productivity under such conditions needs technological innovations to help breeders to develop suitable varieties with desired agronomical traits. One of the perquisites for breeding is the availability of genetic diversity in the targeted crop and the appropriate method for assessing the genetic diversity to initiate breeding experiments. In recent years, substantial developments have been made to develop tools for deciphering genetic diversity and promoting sustainable agriculture. Cereals belonging to the family Gramineae include important crops like wheat, rice, maize, millets, sorghum, oat, barley, rye, and triticale (a hybrid of rye and wheat). Cereals are the primary source of essential nutrients and energy in the day-to-day life of human beings, either consume directly or via their processing and developed into various useful eatable items. Substantial efforts have been made to develop suitable varieties of cereals using both conventional and modern tools. Tools for assessing genetic diversity have been refined over the years with the advent of recombinant DNA technology, genomics, and bioinformatics. With the availability of the crop genome sequences, several markers have been identified and expedited the breeding process. The conventional markers based on morphological traits have been largely replaced by stable molecular markers based on DNA and proteins. Diverse types of molecular markers are being used in crop breeding programs, though the suitability may vary from crop to crop. In the present chapter, an overview of molecular markers and their relevance for assessing and utilization of genetic diversity in the breeding of cereals crops for developing superior varieties have been discussed.