**3.4 Molecular breeding**

In recent years, application of molecular breeding techniques has increased in field of plant breeding. Biotechnological tools viz., NGS, GWAS, MAS, and QTL mapping etc. have been utilized at larger scale in studies related to plant breeding. In India, only two aromatic varieties (Basmati type) have been developed by using molecular breeding method. **ImprovedPB-1** has been developed which is resistant to bacterial blight (*Xanthomonas oryzae* pv. *oryzae*). Two bacterial blight gene (Xa13 and Xa 21) has been introgressed in PB-1 through Marker Assisted Backcross Breeding from donor parent IRBB55 [16]. PB-1718 is developed through MAS from NIL of PB-1121; the variety posses bacterial blight resistance gene Xa13. However, genetic mapping [17], QTL mapping [18], whole genome wide SNP marker analysis [19] have been used to study aroma genes of aromatic rice and other quality traits too.
