Multi-Trait Diverse Germplasm Sources from Mini Core Collection for Sorghum Improvement

Abstract

Sorghum is a multipurpose crop cultivated in over 100 countries, but its productivity is constrained by several biotic and abiotic stresses. Therefore, sorghum improvement programs largely focus on developing high-yielding cultivars with multiple traits including stress resistance, bioenergy and nutritional quality. This study was undertaken to meet breeders’ needs to develop such cultivars and identify diverse germplasm sources with multiple traits. The 242 sorghum mini core accessions were evaluated for agronomic traits (yield, maturity, 100-seed weight) in two post-rainy seasons under optimally irrigated and drought conditions and identified 21 accessions as a sources for agronomic traits. The evaluation of mini core revealed 70 accessions resistant to biotic stress, 12 to abiotic stress, 13 for bioenergy traits and 27 for nutritional traits. The 13,390 single nucleotide polymorphism markers on mini core were used to identify genetically diverse accessions with desirable agronomic traits: IS 23684 (nutrition traits, diseases, insect pests), IS 1212 (earliness, nutrition traits, drought, seedling vigor, diseases), IS 5094 (yield, drought, diseases, insect pests), IS 473 (earliness, diseases), IS 4698 (yield, Brix %, insect pests) and IS 23891 (greater seed weight, yield, Brix %, drought, diseases). These are useful genetic resources that meet breeders needs to develop agronomically superior sorghum cultivars with desirable combinations of multiple traits and a broad genetic base.

Keywords

• agronomic traits
• biotic and abiotic stresses
• genetic diversity
• mini core
• sorghum
• trait-specific germplasm