**7. Molecular technique to enhance rice breeding activities**

Recent progress in molecular biology and biotechnology increases opportunities to use rice genetic tools not addressed in previous programs for rice production. The availability of genomic, phenotypic, geographical, and ecological information among other sequence data, when analyzed together, enables researchers to strategically plan experiments based on established models predicting plant performance [3, 30]. Molecular marker technology and marker-assisted selection (MAS), molecular mapping of genes and QTLs and the generation of hybrids and alien introgression lines [31–34] are just a few of the molecular approaches used in modern rice breeding. MAS is a form of genomic assisted breeding that uses molecular markers to map QTLs or unique genes linked to phenotypes or target traits in order to select individuals with desirable alleles for desired traits [32]. MAS

has many benefits over traditional phenotypic selection, including the fact that it is easier than phenotypic screening, that selection can be performed at the seedling level, and that a single plant can be selected based on its genotype [35].

Breeding for improved grain is complex because many of the quality traits are phenotyped using subjective and or expensive biochemical methods. As a result, scientists have been able to map/clone several QTLs/genes for various quality traits and developed molecular markers to aid in grain quality selection. Co-dominant marker, making it ideal for marker-assisted backcrossing for recessive trait like aroma, since lines carrying the aroma gene can be selected in the heterozygote state without having to screen progeny [36, 37]. Other researchers have produced markers for the 8-bp deletion in exon 7 of chromosome 8. Other alleles in the BADH2 gene, such as a 7-bp deletion in exon 2 [38–40] and a 3-bp insertion in exon 13 found in aromatic rice varieties from Myanmar [41], have also been functionally identified. Around the world, functional markers for RM 190, a waxy gene SSR and waxy SNPS on intron (In1), exon 6 (Ex6) and exon 10 (Ex10) are used to select for AAC and RVA around the world [42]. The waxy SNP haplotypes have been found to be more effective in selecting for AAC and RVA than the RM 190 haplotype across these three SNPs in the waxy genome [43–47].
