Applications of Marker Assisted Selection in Silkworm Breeding for Abiotic Stress Tolerance

Silk produced from mulberry silkworm, Bombyx mori L., has commercial applications in various fields of sciences. Improvement in silk quality and quantity can have profound benefits to the applied fields. Abiotic stresses including high temperature, high humidity, and fluoride pollution during silkworm rearing can affect the silk quality and quantity. Abiotic stress tolerant silkworm breeds developed through molecular approaches could be an answer to avoid losses in silk quality and quantity. Recent advances in the silkworm genomics reported whole genome sequencing, draft genome, 40 genome resequencing, and construction of linkage maps using molecular markers, and successful marker-trait associations can pave the way for applying marker assisted selection (MAS) in silkworm breeding. Molecular MAS involves screening of the breeding population for DNA markers associated with targeted genes which improves the accuracy and efficiency and reduces breeding period with minimal drag around the target gene to achieve the breeding target. In this chapter, several aspects of breeding for tolerance to abiotic (high temperature, high humidity, fluoride pollution) stress with special emphasis on molecular approaches being utilized for silkworm breed development across the world are reviewed. This chapter provides insights on abiotic stress tolerant silkworm breeds/hybrids and their commercial utilization in India.