Location: Grain Quality and Structure Research
Project Number: 3020-30600-002-024-A
Project Type: Cooperative Agreement
Start Date: Sep 1, 2025
End Date: Aug 31, 2028
Objective:
The objective of this project is to identify genes governing sorghum grain quality characteristics (e.g. physical kernel properties, starch, protein, fat, and lysine) and develop sorghum germplasm with enhanced value and that maintains agronomic performance. Molecular markers will be developed to facilitate grain sorghum breeding to meet different market needs based on specific grain quality profiles.
Approach:
The goals of this project will be achieved through three Specific Objectives:
Specific Objective 1: Identify key genes controlling major grain quality traits (starch, protein, fat, lysine) from a library of plants having mutations in each candidate gene controlling synthesis of starch, protein, fat, and lysine physiological networks (based on the maize and rice literature). These sorghum lines are ideal to test gene functions and physiological tradeoffs among different grain quality pathway alleles (e.g. to study tradeoffs between protein and starch synthesis). Both reverse and forward genetics approaches to validate key genes controlling sorghum grain quality using a mutant population in the Specific Objective 1: Elucidate the interactions among major sorghum grain quality traits—including starch content, protein composition, and seed size—and identify allele combinations that improve grain quality without significant tradeoffs in yield or productivity. Both reverse- and forward-genetics approaches will be used to validate key genes controlling sorghum grain quality using a mutant population in the Tx623 genetic background. These sorghum lines provide an ideal system to assess gene function and physiological tradeoffs among grain-quality pathways, such as the balance between protein and starch biosynthesis. pecific Objective : Develop molecular markers and create improved sorghum lines. Beneficial alleles identified in Objective 1 will be introgressed into elite sorghum inbred lines using marker-assisted selection. Molecular markers will be developed using a competitive allele-specific PCR (KASP) approach to enable efficient, accurate, and high-throughput tracking of target alleles during breeding.